JPH0340595A - Time division communication method for mobile body communication - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a time division communication method for a wireless communication channel in mobile communication. More specifically, a unique radio channel is provided, and one of the many mobile radios within the service area communicates by setting up a radio link with the opposing radio base station. When another mobile radio □ wishes to communicate using this radio channel, the other mobile radio □ requests to communicate using this radio channel. The present invention relates to a radio channel division communication method that makes it possible to set up a radio line between a radio device and the radio base station using transmitting/receiving diversity using the radio channel.

[Prior Art] In conventional mobile communications, it has been adopted, for example, in the automobile system of NTT (Nippon Telegraph and Telephone Corporation), which is in commercial service. This will be explained with reference to FIG. A plurality of radio channels are assigned to a certain radio base station 13 in order to simultaneously communicate with a plurality of mobile radio devices 15 installed in each of the many automobiles that exist within a zone 14 that is its service area. . On the other hand, each mobile radio device 15 is equipped with a function that allows selective use of one of a large number of radio channels (referred to as multi-channel access).When communicating with the radio base station 13, the mobile Radio 1
5 communicates a control signal via the radio base station 13 to the radio line control station 12 which determines the use of radio channels of a large number of radio base stations 13, and determines the call channel number to be used for communication according to instructions from there. The system is configured to communicate with subscribers of the telephone network 10 via the exchange 11 including the switches S.

Furthermore, in wireless communication, transmitting/receiving diversity is a commonly used technique. The same signal is transmitted at the same time from multiple transmitters with different frequencies at the transmission point,
Frequency diversity is obtained by tuning multiple receivers to the transmission frequency at distant reception points and adding them after detection, or by dividing the transmission output obtained from one transmitter at the transmission point. This method is called transmitting space diversity, in which the signals are coupled to transmitting antennas installed in different locations, and then guided to a receiver at distant receiving points using a single antenna to obtain a detection output. There is. Furthermore, at the transmitting point, the output of the transmitter is guided to one antenna for transmission, and at the receiving point, which is distantly separated, multiple antennas are installed in different locations and each is guided to the receiver. The method of adding signals after frequency steps or detection is called receive diversity.

In the above transmitting/receiving diversity, amplitude modulation and angle modulation are used to modulate the signal.

Roughly speaking, a method in which the transmission frequencies from the radio base 8 and the mobile radio device are the same, that is, the same radio frequency is used as the transmitting and receiving frequency, is also used in the digital mobile communication system.

[Problem to be Solved by the Invention] In this case, if the number of radio channels provided to a certain radio base station for calls is 10, the number of radio channels provided to a certain radio base station for calls is 10, Since it is possible to allocate separate wireless channels to communication requests, it is possible to make calls without causing wireless interference, but the call request from the mobile wireless device that made the 11th request Because there was no wireless channel to allocate, calls could not be made (calls were lost). This was an example of using a wireless channel to transmit an analog signal, but even if the audio is digitally modulated, a single
Channel Bar Carrier (Single Channel
5CPC, that is, a system in which one telephone (communication) signal is carried and transmitted on each carrier wave, still has the above-mentioned unresolved problems.

Furthermore, there is a problem to be solved in that the bandwidth of the signal is fixed using the assigned radio channel, and a signal having a wider bandwidth than this bandwidth cannot be transmitted.

Roughly speaking, when a system is provided with multiple radio channels, for example, when a mobile radio makes a call, it checks which radio channel is available (called carrier sense) and then uses the call signal. However, in the present invention, since the wireless channel given to the system is only 1@1, the carrier sense circuit is omitted, and the empty time slot necessary for making a call is It is now necessary to investigate only the presence or absence of , making it possible to simplify and economize.

[Means for Solving the Problems] A wireless reception circuit includes a plurality of wireless base stations each having a wireless transceiver, a reception mixer that communicates while moving within a service area covered by the plurality of wireless base stations, A wireless transmitting circuit having a transmitting mixer, a switching receiving means including a local oscillator that can switch and receive a wireless channel signal before the reception of the wireless receiving circuit, and switching the wireless channel signal to the transmitting mixer of the wireless transmitting circuit. In a mobile radio device that includes a switching transmission means including a local oscillator that can transmit, the transmitted signal @ (baseband signal @) is divided into predetermined time interval units and stored in a storage circuit, and when read out, it is stored in the memory circuit. Read out at a predetermined time slot at a speed n times faster than the speed at which it is stored in the circuit, angle-modulate or amplitude-modulate the carrier wave with the signal accommodated by this time slot, and transmit and receive intermittently in time. a radio reception circuit that is built into a mobile radio device and a radio base station and has reception mixers facing each other and communicating;
A switch circuit is provided for a wireless transmission circuit having a transmission mixer, a local oscillator applied to the reception mixer of the wireless reception circuit, and a local oscillator applied to the transmission mixer of the wireless transmission circuit, and the output of the local oscillator applied to each is intermittent. , and this intermittent state is synchronized in both transmission and reception, and the same intermittent transmission and reception as described above is synchronized with that of the wireless base station for mobile radio devices communicating oppositely, and the receiving side uses the predetermined time slot. In order to extract only the signals accommodated in the wireless receiver, the wireless receiving circuit is opened and closed to receive the signal, and the signal obtained by demodulation is stored in a storage circuit. By providing communication path control means for setting a communication path with a predetermined mobile radio device using a predetermined time slot in the radio base station, the original signal transmitted can be read out at a low speed of 1. We have constructed a system that enables the reproduction of certain baseband signals at radio base stations and mobile radios, and includes a gateway switch for connecting the general telephone network and the radio base stations.

As a result, if there are empty slots that are not used for communication within the time-divided time slots of the radio channel given to the system, calls will not be made to mobile radios that have requested a new call. This also makes it possible to continue a call even to a mobile radio that moves from an adjacent zone during a call. It became possible to perform diapercity communication with wireless base stations. When transmission of a wideband signal is required, it has become possible to easily transmit a wideband signal by using the necessary number of time slots if there are empty time slots. In this way, it has become possible to realize a system with a high degree of effective frequency utilization.

[Operation] A radio base station and a large number of mobile radio devices exist within its service area, and in order for any number of mobile radio devices to be able to communicate with the radio base station, one radio channel is The system is divided into a plurality of time slot series, and a system has been constructed in which one of these time slot series can be selected and used for communication. If one mobile radio device is communicating with a radio base station and another mobile radio device transmits to this radio base station, the mobile radio device that newly wishes to communicate will be sent a message on the radio channel in use. , one of the unused time slot sequences is given to enable communication with the radio base station, so that the plurality of sets of communications can be performed without interfering with each other and in a self-contained manner. This makes it possible to carry out communications without any adverse effects on communications.

Here, for example, when the wireless base station is transmitting in a predetermined time slot, the mobile radio device concentrates on receiving the predetermined time slot, and the mobile radio device takes turns transmitting the predetermined time slot. When sending a slot,
By dedicating the radio base station to reception in its predetermined time slot, it also allows only one radio frequency to be used for transmission and reception, thereby improving radio frequency utilization efficiency.

Furthermore, in order to maintain and improve the quality of communication while one radio base station and mobile radio are communicating using one time slot in the radio channel, a certain communication quality is set. One other time slot is used to communicate with one other radio base station that satisfies the following. Since it is now possible to transmit data using multiple time slots even to terminal devices that use broadband signals, the service functionality of the mobile communication system has been improved.

[Embodiment] FIG. 1A, FIG. 1B-1, FIG. 1B-2, and FIG. 1C show a system configuration for explaining an embodiment of the present invention. This system shown here uses a so-called small zone configuration, but the document Ito ``Proposal of mobile phone system - An approach to ultimate communication'' IEICE technical report C388-88 November 1985, etc. As shown, it is assumed that a so-called micro cell is used in which the size difference of each zone is extremely small, within one string.In this case, each wireless zone has a large overlap, and one wireless zone At the same time, it also serves as another wireless zone.

In FIG. 1A, 10 is a general telephone network, 11 is an exchange on the side of the telephone network 10, and 20 is a gateway exchange for connecting the exchange 11 and a wireless system. The gateway switch 20 controls a plurality of wireless base stations 30 and many mobile wireless devices in order to set up and release wireless lines and perform channel switching in conjunction with zone migration. A communication control unit 21 that controls the n stations 30-1, 30-2 to 3O-rl, a 10 identification unit 24 that identifies the identification number of the mobile radio, and a an S/N monitoring unit 25 that monitors communication quality when received by the wireless base stations 30-1 to 30-n;
Each wireless base station 30 is controlled by the communication control unit 21.
-1 to 30-n and the switch 11 and a switch group 23 necessary for communication system switching is included.

However, since the switch u23 in FIG. 1A is simple, only three incoming lines from the exchange 11 are shown, and the wireless base 830-
Transmission signal from 1 to 30-ml 22-1-'1.22
-1-2 to 22-1-m and 22-2-1.22-2
-2 to 22-2-m to 22-n-1, 22-n-2
The outgoing line for transmitting .about.22-nm is an nxm line.

The wireless base M2O includes a group of communication path switches that interface with the barrier exchange 1120, a communication path control section that controls this, an ID identification storage section, a circuit that performs signal speed conversion, and time slot assignment and selection. circuit, 1ii116
1 and a device for transmitting and receiving wireless channels, and in addition to setting and canceling wireless lines, it also has a wireless transmitting and receiving circuit that transmits and receives wireless signals to and from many mobile radio devices 100.

Here, between the barrier switch 20 and the wireless base station 30,
Communication signals 22-1 to 22-2 including each call signal and control signal
There is a transmission line that transmits 2-m.

In FIG. 1B-1, the wireless base station 30-1 or 30-
The circuit configuration of a mobile radio 1100 that communicates with the mobile radio 1100 is shown. Received signals such as control signals and call signals received by the antenna section enter a radio receiving circuit 135 that includes a receiving mixer 136 and a receiving section 137, and the output communication signal is inputted to a speed recovery circuit 138 and a clock recovery band 141. be done.

In the clock regeneration band 141, a clock is regenerated from the received signal and transmitted to the speed restoration circuit 138 and the control unit "14".
0 is applied to the timing generator 142 and speed conversion circuit 131.

The speed restoration circuit 13B restores the speed (pitch in the case of an analog signal) of the compressed and segmented communication signal in the time slot of the received signal of the radio channel to obtain a continuous signal, and converts it into a signal. The mixing circuit 152 mixes the mixture and sends it to the telephone unit 101゜speech quality monitoring unit 157. and I
It is input to the D information collation storage section 182.

The communication signal output from the telephone unit 101 is divided at predetermined time intervals by the speed conversion circuit 131, and its speed (pitch in the case of an analog signal) is set to high speed (compression), and the communication signal is sent to the transmission mixer 133 and the transmission unit 134. A wireless transmission circuit 13 including
2, the transmission signal is sent out from the antenna section using a certain time slot, and is received by a plurality of radio base stations 30. The speech quality monitoring section 157 to which the output of the signal @mixing circuit 152 is applied constantly monitors the speech quality during communication, and reports it to the control section 140 when it deteriorates. In the ID information verification storage unit 182, the mobile radio 11100
It remembers its own ID (identification information) and identifies and remembers which zone it is in.

In the timing generator 142, the transmission/reception intermittent controller 123. It supplies necessary timing to the ``a degree conversion circuit 131 and speed restoration circuit 138.

This mobile radio device 100 includes local oscillators 121-1 to enable transmission and reception of radio channels used for signal transmission.
1 and 121-2, and selector switches 122-1, 12
2-2, and a transmission/reception intermittent controller 1 that generates signals for switching the changeover switches 122-1 and 122-2, respectively.
23 and a timing generator 142, and the local oscillators 121-18 and 121-2, the transmission/reception intermittent controller 123, and the timing generator 142 are
controlled by. A reference frequency is supplied from a reference crystal oscillator 120 to each local oscillator 121-1 and 121-2. With such a configuration, it is possible to communicate with a plurality of wireless base stations 30 using one channel.

FIG. 1B-2 shows the internal configuration of the radio receiving circuit 135. The received signal received by the antenna section is sent to switch 1.
22-1 to the receive mixer 136 to which the local oscillation frequency from the local oscillator 121-1 is applied;
Its output is applied to an intermediate frequency amplifier 143. The signal amplified by the intermediate frequency amplifier 143 is sent to the gate circuit 1
44 and the clock regenerator 141. This gate circuit 144 is for extracting only the signal of a desired time slot without interference from other time slots. The output of the gate circuit 144 is demodulated by the discriminator 145 and passed through the gate circuit 146 to the speed restoration circuit 1.
38. This gate circuit 146 removes transients from the demodulated waveform.

A wireless base station 30 is shown in FIG. 1C.

Communication signal 22-1 of m channel with gateway exchange 20
~22-m has an interface via a transmission path 'Tj
It is connected to the signal processing section 31.

Now, the communication message M22- sent from the barrier switch 20
1 to 22-m5 are input to the signal processing unit 31 of the wireless base station 30. The signal processing unit 31 is equipped with an amplifier to compensate for transmission loss, and also has a function for transmitting and receiving diversity using two or more time slots, and dividing the signal into multiple wireless transmitting and receiving units. In addition to the m function, if there are two trunk lines between the gateway switch 20 and the gateway switch 20, a so-called 2-wire to 4-wire conversion is performed. That is, the input signal and the output signal are mixed and separated, and the input signal from the barrier exchange 120 is sent to many switches 5WR1-1, 5WR1.
-2,-, SWR'l-m, 5WR2-1, 3WR2-
2,-, SWR2-m, ...-,5WRn-1,5
SWRs including WRn-2,-, SWRn-m, and 5WT1-1, 5WT1-2. -, SWT1-m, 5
WT2-1゜5WT2-2. -, SWT2-m-, -,
A signal speed conversion circuit including many signal speed conversion circuits 51-1 to 51-n via a switch group 83 configured to include SWTs including SW'Tn-1, 5WTn-2, =-, and SWTn-m. It is sent to circuit group 51.

Further, the output signal from the signal restoration circuit group 38 including the signal speed restoration circuits 38-1 to 38-m is sent to the signal processing unit 31 via the switch group 83, and the communication signal 22- 1 to 22-m and are transmitted to the barrier switch 20. Here, the switch group 83 is a transmission switch S
They are roughly divided into a WT and a receiving switch SWR, both of which are controlled by the communication path 111m section 81 to open and close the switch group 83 to achieve the desired purpose and to enable transmitting and receiving diversity. Operate.

The IDm-specific storage unit 82 is used to identify and store the ID of the mobile radio device 100. In addition, the communication path 11111 part 8
1 controls the communication path by opening and closing the switch group 83 according to commands from the control section 40, and also has the function of providing information and requesting control from the communication path control section 81 to the control section 40.

Among the above, the input signal from the barrier exchange [120] passes through the switch group 83, and then passes through many signal speed conversion circuits 51-1 to 51-5.
The signal is input to a signal speed conversion circuit group 51 including 1-m, and subjected to speed (pitch) conversion at predetermined time intervals. In addition, the signal transmitted from the wireless base station 30 to the barrier exchange 1M20 is such that the output of the wireless receiving circuit 35 is
is input to the signal speed restoration circuit group 38 via the signal speed (
After the pitch is converted, the signal passes through the switch group 83 and is input to the signal processing section 31 . Note that, similar to FIG. 1B=1, the radio receiving circuit 35 is applied with a local frequency from a local oscillator having a circuit for multiplying the output of the reference crystal oscillator.

Now, the control of the radio reception circuit 35 or the output of the call signal is performed by a signal selection circuit 39 that selects a signal for each time slot.
-1 to 39-n is input to the signal selection circuit group 39,
Here, the speech signal is separated in accordance with the time slot included in the radio channel received by the radio receiving circuit 35. After this output is restored to a signal speed (pitch) by a signal speed restoration circuit group 38 including signal speed restoration circuits 38-1 to 38-n provided corresponding to each call signal, a switch group 83 is output. It is input to the signal processing unit 31 through the 4-wire -2
After undergoing line conversion, this output is sent as a communication signal to the barrier switch 20.
22-1 to 22-m.

Here, the specific configuration of the radio receiving circuit 35 is as follows.
This is the same as the radio receiving circuit 135 of the mobile radio device 100 shown in FIG.

Next, the functions of the signal speed conversion circuit group 51 will be explained.

By storing input signals such as audio signals and control signals g divided into a certain length of time in a storage circuit, and changing the speed when reading them out, for example, reading them out at a speed 15 times faster than when they were stored, the signals can be stored. It becomes possible to compress the time length. The principle of the signal speed conversion circuit group 51 is the same as when playing back audio recorded by a tape recorder at high speed, and in reality, for example, COD (Char
geCoupledDevice), 33[)
(Bucket Brigade Device) can be used, and the memory used in television receivers and tape recorders that compress or expand the time axis of conversations can be used (References: Koita et al. "Conversation Time"). Tape recorder that compresses/expands the shaft Nikkei Electronics July 26, 1976 92-1
Page 33〉.

The circuit using the COD/BBD exemplified in the one-word speed conversion circuit group 51 can be used as it is in the signal speed restoration circuit group 38 as described in the above-mentioned document, and in this case, the clock generator Clock from 41 and control unit 40
This can be achieved by making the reading speed slower than the writing speed in response to a timing signal from a timing generator 42 that generates timing based on a control signal from the timing generator 42 .

Control or call signals output from the barrier switch 20 via the signal processing section 31 are input to the signal speed conversion circuit group 51, where speed (pitch) conversion processing is performed and the signals are converted into signals for each time slot. Signal assignment circuit group 52 to be assigned
is applied to The signal allocation circuit group 52 is a buffer memory circuit that stores one section of high-speed signals output from the signal speed conversion circuit group 51, and uses the timing from the timing generation circuit 42 given by instructions from the control section 40. Read the signal in the buffer 7 memory with the information,
It is transmitted to the wireless transmission circuit 32. As a result, communication information is arranged chronologically in series with no overlap when viewed in response to call signals, and if all control signals or call signals described later are implemented, it will be as if it were a continuous call signal. It becomes like a wave.

The state of this compressed signal is shown and explained in FIGS. 2A and 2B.

The output signal of the signal speed conversion circuit group 51 is transmitted to the Shinkyu assignment circuit group 5.
2 and are given time slots in a predetermined order. SDl and SD2 in Figure 2A (a)
．． -, SDn indicate that the speed-converted communication signals are allocated to each time slot at the output of the wireless transmission circuit 32.

Here, as shown in the figure, one time slot accommodates a synchronization signal and a control signal or a call signal (and a control wJ signal).If a call signal is not implemented, the call path control unit 81 With only the added sync signal, the empty slot signal is added to the speech signal part.In this way,
As shown in FIG. 2A (a), in the radio transmission circuit 32, signals forming one frame are applied to the modulation circuit in time slots SD1 to SD5Drl.

This time-series multiplexed signal is subjected to amplitude or angle modulation in the radio transmission circuit 32, and is then sent out into space from the antenna section.

When making or receiving a telephone call, radio base 1 station 3 is activated prior to the call.
0 and the mobile radio device 100, it is possible to use either within the speech signal band or outside the speech signal band.

Figure 3A shows these frequency relationships. That is, the same (a
) is an example of an out-of-band signal, and as shown in the figure, the low frequency side (250H2) or the high frequency side (3850Hz>) can be used.This signal can be used, for example, when you want to send a control signal during a call (for example, , when you want to apply zone switching or diversity during communication).

These control signals are created in the control section 40, and are also created and sent by relaying or converting the 1tli control signal from the barrier exchange 20 and the control signal from the communication path control section 81 in the control section 40.

The control signal sent from the mobile radio l1100 is received by the radio receiving circuit 35, subjected to ffX processing by the control unit 40, and
If necessary, the communication path 1t11+control section 81 is sent to the gateway exchange 20.

FIG. 3A (b) shows an example of an in-band control signal, which is used when making and receiving calls.

The above examples all involve tone signals, but by increasing the number of tone signals or modulating the tone to create a subcarrier signal, it is possible to transmit many types of signals at high speed.

The above was a case of analog signals, but if a digital data signal is used as a control signal, it is also possible to digitally encode the call signal and time-division multiplex the two to be transmitted. The circuit configuration of is shown in Figure 2E (
b).

FIG. 2E(b) shows that an analog audio signal is digitized by a digital encoding circuit 91, and a multiplex conversion circuit 92 multiplex-converts it and a data signal.1. This is an example of a case where the signal is applied to a modulation circuit included in the wireless transmission circuit 32.

Then, it is received by the opposite receiver, and the second E
If the operation is reversed to that shown in FIG. 3(b), it is possible to extract the call signal and the control signal separately.

On the other hand, the signal sent from the mobile wireless device 100 is received by the antenna section of the wireless base station 30, and is received by the wireless receiving circuit 35.
is input to. FIG. 2A (b) schematically shows this upstream input signal.

That is, time slot SU1°SU2. ...S
un is mobile radio 100-1.100-2°...,
100-n shows a transmission signal addressed to the wireless base station 30.

Also, each time slot l-3tJ1. SU2...
If the contents of sun are shown in detail, as shown in the lower left of FIG. 2A (b), it consists of a synchronization signal and a control signal or a call signal (and control signal). However, depending on the short distance between the radio base Q30 and the mobile radio device 100 or the signal speed, it is possible to omit the synchronization signal.

Roughly speaking, the waveform of the radio carrier wave of the above-mentioned uplink radio signal within a time slot is schematically shown as shown in FIG. 2B (C).

Now, among the input signals that have arrived at the wireless base station 30, the control signal is immediately sent to the control unit 40 from the wireless receiving circuit 35.
added to. However, depending on the size of the speed conversion rate, it is also possible to apply the speech signal to the control section 40 from the output of the signal speed restoration circuit group 38 after performing the same 98 processes. Further, the call signal is applied to the call @ selection circuit group 39.

The signal@selection circuit group 39 includes it+ll from the control unit 40.
In accordance with the instruction of the W signal, a timing signal from a timing generation circuit 42 that generates a predetermined timing is applied, and a synchronization signal, control signal, or speech signal is separated and output for each time slot 5tJ1 to Sun. Each of these signals is input to a signal speed restoration circuit group 38. This circuit has the function of inversely converting the speed conversion circuit 131 (Fig. 1B-1) in the mobile radio device 100 on the transmitting side, and as a result, the original signal is faithfully reproduced and
It will be sent to address 0.

The manner in which signals are transmitted in the signal space according to the present invention will be explained below using the required transmission band.

As shown in FIG. 1C, the control signal from the control section 40 is applied to the wireless transmission circuit 32 in parallel with the output of the signal allocation circuit group 52. However, depending on the size of the speed conversion rate, it is also possible to apply the signal to the wireless transmission circuit 32 from the output of the signal allocation circuit group 52 after performing the same processing as the call signal.

Next, in the mobile radio 11100, as shown in FIG. 1B-1, among the functions of the radio base station 30, when two call signals are transmitted using two time slots, It has the required circuit configuration. Original signal, such as a telephone call signal (0.3KH2 to 45KHz)
FIG. 3B shows the frequency distribution on the output side when the signal passes through the signal speed conversion circuit group 51 (FIG. 1C). In other words, if the audio signal is converted 15 times as described above, the frequency distribution of the signal will be 4.5 as shown in Figure 3B.
It was expanded to 2 days from KH2 to 45. The figure shows a case where the control signals are simultaneously transmitted using the lower frequency band of the call signal. If the control signal behind this signal (0.2-4.0 KHz > and one telephone call @ (4.5-45 KHz and expressed as SDl) is accommodated in time slot 1~, e.g. SDl. Other time slots SD2~5Drl
The same applies to the speech signals contained in the .

That is, time slot soi <i=2゜3, -
, n) accommodates the control signal (0.2~4°0KHz>) and the communication signal @CHi (day 2 on April 5~45). However, the signals within each time slot are chronologically The signals in multiple time slots are not applied to the radio transmitting circuit 32 at the same time.

When these speech signals are applied to the angle modulation section included in the wireless transmission circuit 32 together with the Iii+ control signal, at least f C±45K tolZ is required as the required transmission band. However, fC is the radio carrier frequency. Here, if there are multiple radio channels given to the system, the height of these frequency intervals! From the first limit onward, the signal speed conversion by the signal speed conversion circuit group 51 is limited to a certain value. If the frequency interval of a plurality of wireless channels is frep, and the maximum signal speed due to the above-mentioned high-speed audio signal is fH, the following inequality must hold between the two.

f>2f.

ep On the other hand, in digital signals, audio is usually 16 to 64 kb.
Since the signal is digitized at a speed of about /s, it is necessary to read it by raising the scale on the horizontal axis in Figure 3B, which explains the case of an analog signal, by about one digit, but the relationship in the above equation holds true in this case as well. .

Further, the control signal that enters the radio base station 30 from the mobile radio device 100 is input to the radio reception circuit 35, but a part of its output is input to the control unit 40, and the rest is sent to the three signal selection circuit groups. The signal is sent to the signal speed restoration circuit group 38 via. After the latter $ control signal undergoes speed conversion (conversion to a low speed signal) that is completely opposite to that at the time of transmission, it becomes the same signal speed as that used in the general telephone network 10 and is transmitted via the signal processing section 31. Exchange the barrier! Sent to fi20.

FIG. 1D shows another embodiment 100B of the mobile radio 100.
It is shown. Here, Figure 1B (No.) Figure B-1,
The difference from the mobile radio R100 shown in Figure B-2 (including Figure B-2) is that it is equipped with one local oscillator 12]-1. The transmission/reception intermittent controller 123B operates based on the control signal from the control unit 140B to switch the switches 122-1 and 1.
22-2 is turned on and off, and the output of the local oscillator 121-1 is applied alternately to the reception mixer 136 and the transmission mixer 133.

Next, various operations of the system according to the present invention will be explained in the following order, and the high practicality of the present invention will be theoretically proven. In the explanation, a case of a telephone call signal will be taken as an example, and a non-telephone signal will be explained after that.

1) Location registration 2> Call origination operation 3) Call reception operation 4) Time slot switching operation during a call 5> Transmission/reception diversity performed between multiple wireless base stations (6) Diperity effect according to the present invention and the conventional method Comparison (7) Detailed description of the present invention (i> Adjacent radio channel interference (n) Self-channel interference (III) Co-channel interference (IV) Pulse noise removal method when receiving a signal (v) Transmission signal Effect of delay time (Vl) Calculation of effective frequency utilization rate (8) Application of the present invention to communications using non-telephone systems (wideband signals) other than speech signals (9) Same as transmission and reception of radio base stations and mobile radio acids Application of the present invention to a system using radio frequencies (10) Advantages of the system to which the present invention is applied in terms of effective frequency utilization (1> Location registration The mobile radio BIloo used in the present invention has the 1B-1
There are various configurations as shown in Figures 1B-2 and 1D, any of which can be used. However, for convenience of explanation, the mobile radio device 100 shown in FIG. 1B-1
The main focus is on location registration operations. Below, mobile radio device 100
．． ]OOB': Simply referred to as mobile radio device 100.

home area, which is the permanent location of the mobile radio l1100;
Alternatively, when the gateway switch 20 and the surrounding wireless base stations 30-1 to 30-p are already operating in the ROHM area, which is an area within the service other than the home area, the power switch of the mobile wireless device 100 is turned off. When it is turned on and starts operating, the first thing it does is register its location.

Prior to explaining the operation, it will be assumed that in the system to which the present invention is applied, there is only one radio channel to the radio base station 30, and this is commonly used by a large number of mobile radios 1100.

Let the downlink frequency transmitted by the radio base station 30 and received by the mobile radio device 100 be 1, and the uplink frequency transmitted by the mobile radio device 100 and received by the radio base station 30 be fl.And when applied to the small zone method There are many wireless base stations 30 in the vicinity, and the calling signal etc. from the mobile wireless device 100 can be received by many wireless base stations 30. In order to do this, it is assumed that the following method is adopted.

i> All frames or time slots in all radio channels transmitted from each radio base station 30 are synchronized by the synchronization signal supplied from the gateway exchange 20.

ii> In addition to the signal transmitted from the barrier switch 20 to the mobile radio 1100, when the signal is transmitted via a plurality of different radio base stations 30, the timing of transmitting the signal from each FI line base station 30, and the format of the signal.

The modulation depth etc. are all the same.

However, other channel allocation methods and other methods for System J vehicles will also be included in the explanation as appropriate.

Furthermore, it is assumed that the following points are taken into consideration in the system design based on the radio wave propagation characteristics of the system to which the microcell is applied.

In other words, when the size of the zone becomes a small zone with a radius of one cord or less, that is, a zone called a microcell,
The radio wave propagation characteristics vary greatly depending on location, and the service area of one wireless base station 30 is significantly different from a circular shape, an ellipse (ellipse), and even an uneven shape? It becomes l-shaped. Therefore, each location in the service area is less likely to be covered by a single wireless zone, but instead becomes a dead area that is not included in any zone, or is covered by multiple wireless zones at the same time. In the former dead area, communication is impossible, so in an actual system, a larger number of wireless base stations 30 than necessary would be installed in order to eliminate this.

As a result, the overlapping of service zones is further promoted.

In such a system, when a location registration signal, which will be described later, is transmitted from the mobile radio device 100, it can be received satisfactorily by a plurality of radio base stations 30.

The flow of the location registration operation under such system conditions is shown in FIGS. 4A and 4B and will be described.

When the power switch of the mobile radio device 100 is turned on, a location registration signal for registering the current location is sent to the nearest radio base station, for example, 30-1°30, using an empty time slot SUI of the uplink radio channel. -p (p=2.3.
...> (S161, Fig. 4A).

This is possible because the radio signals sent from the radio base station 30-1, etc. on the R side include signals indicating that the radio base station 30-1, etc. is talking with other mobile radios, and empty time slots. Signals are chronologically contained and transmitted within each time slot as described above. Each time slot contains a control signal 8 (status display signal) indicating whether a call is in progress or no call, etc., and the time slot in which a call is in progress contains an ID signal of the other party being called. By receiving this, the mobile radio m1oo can perform frame synchronization and time slot synchronization. If a wireless base station 30 in the vicinity uses time slot SD1 for a call with another mobile wireless device, il! ″−3
1, and in the mobile radio device 100, the time slot SDm
Since the empty time slot information within the time slot cannot be received well, other empty time slots are searched for. And at the surrounding wireless base station, for example 30-2,
If the time slot SDI is empty time slot 1~, the empty time slot information that is exactly the same as that of the wireless base station 301 and the ID information of the wireless base station 30-2, for example, are shown in FIG. 2E (a) and It is transmitted as shown in (b).

2. As shown in the figure, it is assumed that empty time slot information is being transmitted from two mutually adjacent radio base stations 30-1 and 30-2 using time slot SD1.

Since the transmission timing is synchronized at both radio base stations 30-1 and 30-2, the nearest mobile radio
0, these signals will be received simultaneously. As a result, since the base station ID and traffic information are different for each radio base station 3'O-1, 30-2, etc., the mobile radio m1oo will generally not be able to receive it well. However, information on empty time slots is available at all times! Base station 30-
Both signals 1°30-2 and 1°30-2 are exactly the same, and include the fact that it is an empty time slot, the slot number, etc., and can be easily received by the mobile radio device 100. Note that the blank time in the second figure means the time during which no wireless signal is transmitted from the wireless base station 30-1, 30-2, etc.
A signal format suitable for the case where it is desired to receive the base station ID and traffic information of the slot in a good manner is shown. In FIG. 2G, the transmission timings from each radio base station 30-1 and 30-2 are shifted in time, and the type of shift is made to match the known number of repetition zones in the small zone method. For example 7. ] 2 is a number such as 19, and each wireless base station 30-1, 30-2 is equipped with this many types.
etc., it is possible to cover an infinitely wide service area.
At 0, each radio base station 3o-1, 30 has no radio interference with each other.
-It becomes possible to receive information from 2nd etc. In addition, FIG. 2F.

In FIG. 2G, the same lyI bow shown in FIG. 2D is omitted from illustration.

According to the method described above, the mobile radio device 100 supplements empty time slots, obtains timing information, uses the empty time slot SUI of the corresponding uplink radio channel, and uses the empty time slot SUI of the corresponding uplink radio channel to determine whether the mobile radio 100 It is possible to receive a location registration request signal addressed to .30-2, etc. Now,
All nearby radio base stations 30 have all receivers waiting to receive signals in all time slots of the radio channel.

Therefore, when a location registration signal is received from the mobile radio device 100 (Sl 62, 3163), many radio base stations 3
0-1.301 (D=2.3...

n>, the reception quality is inspected and the I
D is stored (S164.Sl 65). If the result of checking the reception quality is above a certain value (8166YES)
, 3167YES), sends a location registration request signal to the barrier exchange 20 (Sl 68.3169>.Gateway exchange v1 that received this location registration request signal (S170)
In step 20, a table containing the IDs, received signal quality, etc. of all the radio base stations 301.30-p that have requested location registration of the mobile radio device 100 is created, and each radio base station 30-p is
1.30-p, it is decided to notify the mobile radio 100 of the transmission timing of the time slot number in response (8171, FIG. 4B). For example, wireless base station 30-
For 1, the time slot SD of the downlink radio channel
1. The wireless base station 30-2 has the same <SD2. . . . , and so on, similarly for 3On, the same <SDn.

These are included in the registration completion signal, and each wireless base station 3
0-1.30-D (3172).

Wireless base station 30-1゜30 that received this registration completion signal
-p (Sl 73.Sl 74), the downlink radio channel time slot SD1. SDp (p-2,3
,...> to the mobile radio device 100 (Sl
76, Sl 77).

The registration completion signal transmitted in the time slot specified by the barrier switch 20 in this way is transmitted to the mobile radio device 100.
Good reception with no wireless interference.

After receiving this registration completion signal (S177), the mobile radio device 100 inspects the received content and identifies the ID (identification number) of each registered radio base station 30-1.3O-1).
The information is stored in the information verification storage unit 182 (S178).

With the above operations, the location registration operation is completed and the device enters a standby state for an incoming call.

Next, assume that the mobile radio device 100 moves from the zone in which its location has been registered and moves to an adjacent zone while it is on standby (in a state where it is not talking).
The radio base station 30-1 in the control signal included in each time slot of the radio channel constantly transmitted from the radio base station 30-1, etc.
By comparing the ID information with the ID stored in the mobile radio device 100, the mobile radio device 100 can be identified.

I that is constantly transmitted from the above-mentioned wireless base station 30-1 etc.
The D information may be included in an empty time slot, or may be control information within a time slot that is sent out for communication with another third party. In the latter case, each time slot includes the ID of the wireless base station 30, which will be verified.

In addition, in a system in which signals are not always transmitted from the wireless base station 30-1, etc., the mobile wireless device 100 transmits a location registration confirmation signal at fixed time intervals, and the wireless base station 30 that receives the signal It is possible to confirm the ID of the wireless base station 30 from the transmitted signal.

As a result, the ID of the obtained wireless base station, for example, 30-1
If the information is new base station ID information that is different from the base station ID information previously stored in the mobile radio 100, the mobile radio! 1100 determines that the zone has moved to a new zone, and the control unit 140 (see FIG. 1B-1) updates the location registration in the ID information verification storage unit 182.

That is, using an uplink radio channel having an empty time slot, the signal is transmitted to the destination radio base station (S30-2), which receives the ID information of i1] line of sight [100.

The radio base station 30-2 that successfully received this signal performs the same procedure as already explained, and the gateway switch 20-2
The location registration signal of the mobile radio device 100 is sent to the mobile radio device 100. Upon receiving this signal, the gateway exchange FM 20 operates the ID identification storage section 24 in its own device, rewrites the old information to new information as the location registration information of the mobile radio 11100, and sends the mobile radio from the radio base station 30-2 to the new information. This '@ is communicated to machine 100.

As a result, the location registration of the mobile radio device 100 is updated.

The above update work is necessary because the mobile radio device 100 is in standby mode, and if it moves to a new zone during communication (talking), time slot assignment to the barrier exchange 1m20 will be performed as described later. When this is performed between the new radio base station 30-2 and the mobile radio device 100, the location registration is updated at the same time, so no special operation is required.

The above description has been made regarding the mobile wireless devices 100 and 1008 shown in FIG. 1B-1 and FIG. 1D. In actual systems, they exhibit even greater capabilities as shown below.

j〉 Diperity transmission is possible, and it is possible to send location registration request signals simultaneously using two different time slots.

11> Diversity reception becomes possible, and signals in different time slots from the same or two different radio base stations 30 can be received.

) From i> and ii>, it becomes possible to improve the reliability of the control signal and speed up the registration operation.

(2) Calling operation will be explained using the flowcharts shown in FIGS. 58 to 5C.

When the mobile radio device 100 is powered on, it is already (1
> The location registration operation described in the location registration section has been completed.

Then, when the handset of the telephone unit '101 is off-hook (starting a call) (3201, Fig. 5A), an empty time slot Sun@: in the wireless channel is found and Using this, a calling signal is sent to the nearby wireless base station 30-1, 30-2.V
That is, to explain the operation of the mobile radio device 100, first, regarding reception, the time and time shown in FIG. 2A (a>
This is possible by capturing the same signal in slot SDi. In the control unit 140, the local oscillator 121-1 generates a local oscillation frequency that enables reception of the wireless channel, and the switch 122-1 also generates a local oscillator frequency that enables reception of the wireless channel.
The first side is turned on and fixed.

Synthesizer 121-2 in FIG. 1B-1 generates a local frequency that enables transmission of radio channel CI-11. It is also assumed that the speed restoration circuit 138 is in an operating state.

The switch 122-2 also turns on the local oscillator 121-2 side and becomes fixed. Next, the calling t++llll1 signal output from the telephone unit 101 is sent out using a wireless channel. Further, it is assumed that the speed conversion circuit 131 is in an operating state.

Now, the above control signal is in the frequency band shown in FIG.
Sent using

Controls included in time slot Sun! The l signal includes, for example, the following contents.

) 10° of the mobile radio device 100 itself) 100 of the wireless base station 30 whose location is registered
ID of the called party.

■〉Time slot number in use.

The transmission of this υJllll signal is limited to time slot Sun, and is sent in bursts, and no signal is sent during other time periods, so it does not affect other communications. However, if the speed of the control signal is relatively low,
Alternatively, if the amount of information in the signal is too large to be accommodated in one time slot, it is transmitted one frame later or further using the same time slot in the next frame.

Specifically, the following method is used to capture the time slot Sun. As shown in FIG. 2A (a), the control signal transmitted from the radio base 830 includes a synchronization signal and a subsequent control signal, and by receiving this, the mobile radio Ialoo can perform frame synchronization. become. Furthermore, this m-open signal includes control information such as currently used time slots and unused time slots (empty time slot display). In some systems, the time slot SD+(i=1.2,...
, n) may contain only synchronization and speech signals when they are being used by other communications; By receiving this control signal, the mobile radio 1!1100 can determine which time
It is possible to know whether to send a calling signal using the slot.

Note that if all time slots are in use,
It is not possible to make a call. In other systems, no radio waves are transmitted at all during empty time slots, or
There are cases where no empty slot is displayed in any of the time slots, and in this case, the following audio multiplex signal SD1. It is necessary to search for the presence or absence of SD2, . . . , SDn one after another and check for empty time slots.

Now, returning to the main topic, the mobile radio device 100 that has received the control information sent from the radio base 830 by one of the methods described above determines in which time slot it should send the call control signal, and then determines the transmission You can make decisions including timing.

Therefore, assuming that the time slot Sun for uplink signals is an empty slot, it is decided to use this empty time slot, and the necessary timing is determined from the response signal from the radio base station 30 by sending out a control signal for calling. It is also possible to send out burst-like ill signals.

If there is a call from another mobile radio at the same time, the calling signal will not be properly transmitted to the radio base station 30 due to call collision, and the operation will have to be restarted from the beginning, but this probability is When viewed as a system, this value is kept to a sufficiently small value. If call collisions are drastically reduced. The following method is used. If a mobile radio [100] finds an empty time slot in which it can make a call, it does not use the entire time slot, but rather uses only the first half of the time slot for some mobile radios and only the second half for other mobile radios. This is a method that allows you to use it. In other words, the portion of the time slot used as a calling signal is divided into several types, and this is used to classify a large number of mobile radios into groups, and each group is assigned a time slot within that one time slot. This is a method of giving a belt.

Another method is to create many different frequencies for the control signal,
This is a method of dividing a large number of mobile wireless devices into groups and applying this to each group. According to this method, even if control signals of different frequencies are transmitted simultaneously using the same time slot, no interference will occur at the radio base station 30. The above two methods may be used separately, or when used together, the effects will increase synergistically.

Now, the call control signal from the mobile radio device 100 is sent to a plurality of nearby radio base stations 30-1, 30-2. ...,
30-n, etc., and detects the ID (identification number) of the mobile radio device 100 (3202°3203), and even if the ID of the mobile radio device 100 is unregistered, it is stored at that point. , sends a calling signal to the gateway exchange 20 (3204.5205>).Sends a calling signal to the gateway exchange 20 in the same way as the already registered wireless base station 30.

Since the barrier switch 20 receives similar signals from a plurality of wireless base stations 30-2 and the like in addition to the wireless base station 30-1, it selects a wireless base station 30 suitable for communicating with the mobile wireless device 100. The decision is made after comprehensively examining the traffic conditions, reception quality, etc. in that zone. As a result, the wireless base stations to be used for communication are determined to be 30-1 and 30-2, and the time slots to be used for communication are determined to be 1 and 2, respectively (S206), and this is determined by the wireless base station 30i.

30-2 (3207>.Other wireless base stations 30
to notify that communication is unavailable, or time out without sending any signal. Now, the wireless base station 3 that received the communication command signal
At 0-1.30-2 (3208, 3209>, preparations are made to receive at the designated time slots,
mobile radio BN using time slots SDn, respectively.
Tell loo the instructions from barrier exchange 120 (321
0°5211, Figure 5B>. In the mobile radio device 100, since this signal is transmitted from the radio base station 301.30-2 at the same time and with the same signal content, there is no possibility of radio interference occurring and the signal is received satisfactorily.

In response, the mobile radio 100 transitions to a state in which it can receive data in the two instructed time slots SD1 and SD2, and also transmits signals in the downlink time slots SDI and S.
Two uplinks corresponding to D2, time for must-channel P channel.
SUl which is a slot.

5U2 (see FIG. 2A (b)) is selected. At this time, the control unit 140 of the mobile radio Inl00 operates the transmission/reception intermittent controller 123 and starts operating the switches 122-1.1 and 122-2. S212> At the same time, a slot switching completion report is sent to the wireless base station 30-1.3 using uplink time slots SU1 and SU2, respectively.
0-2 and waits for dial tone (S213>
.

Time slot 5U of the radio carrier wave of this upstream radio signal
The state of 1-1 etc. is schematically shown in FIG. 2B (C). The wireless base station 30 has a time slot SU1.
．． In addition to SU2, SU3 and Sun are included in one frame and sent as uplink signals from other mobile radio devices 100.

Radio base station 30-1 that received the slot switching completion report.
30-2 sends a calling signal to the barrier switch 20 (8214.3215), and the barrier switch 20 that receives the call signal
Now on to mobile radio! 1100 ID detected, barrier exchange 12
0 is turned on (S216>), and a dial tone is sent out (S217).This dial tone is transmitted to the radio base station 3.
〇-1 and 30-2 receive the radio base station 30-1.
, 30-2 to the mobile radio device 100 (
3218.8219>. In this transfer, the same signal contents instructed from the barrier exchange 1m20 are transmitted.

Therefore, the mobile radio device 100 can obtain a time diversity reception effect and can receive signals well.

Now, as described above, the mobile radio device 100 confirms that the communication path has been set (S220). When this state is reached, a dial tone is heard from the handset of the telephone section 101 of the mobile radio 1M100, and the transmission of a dial signal begins. This dial signal is speed-converted by a speed conversion circuit 131, and sent to an upstream time slot SU from a radio transmission circuit 132 including a transmission section 134 and a transmission mixer 133.
1°5tJ2 (3221, Figure 5C) Thus, the transmitted dial message @ is sent to the radio base station 3.
It is received by the radio receiving circuit 35 of 0-1.30-2. This radio base station 30-1, 30-2 has already responded to the calling signal from the mobile radio 100,
As well as giving a slot, the wireless base station 30-1.30
-2 signal selection circuit groups and signal allocation circuit group 52 are operated, and the uplink time slot SU1. Alternatively, SU2 is received and the downlink time slot l-S D 1
Alternatively, the state has shifted to the state where the SD2 signal is transmitted.

In addition, the communication path control unit 81 selects a switch SWR for reception among the switch group 83 according to a control signal from the control unit 40.
1-1, or 1-2, and switch 5 for transmission.
WT1-1. Alternatively, 1-2 is set to the ON state (as shown in FIG. 1C).

Therefore, the dial signal transmitted from the mobile radio device 100 is transmitted to the signal selection circuit 39-1 of the signal selection circuit group 39.
After passing through, it is input to the signal speed restoration circuit 38-1 of the signal speed restoration circuit group 38, where the original transmission signal is restored.
The signal is transferred to the gateway exchange 20 as a call signal 22-1 via the call @ processing unit 31 via the switch group 83 (3222
, 5223>, a call path to the telephone network 10 is set up (S
224).

On the other hand, the input signal from the barrier exchange 1m20 (initial control signal, call signal when a call is started) is transmitted from the wireless base station 30-
1.30-2, switch 5WT of switch group 83
1-1, the signal speed conversion circuit 51-1 of the signal speed conversion circuit group 51 converts the speed, and the signal allocation circuit 52-1 of the signal allocation circuit group 52 converts the time slots 1 to 1-1.
SDI and SD2 are given. Then, the time slot SD1 of the wireless channel downstream from the wireless transmission circuit 32
, or transmitted to the mobile radio device 10O using SD2. In the mobile radio device 100, time slots 5D1-1 . Or, it is waiting for reception in 5D1-2 and is received by the wireless reception circuit 135,
Its output is input to speed restoration circuit 138. In this circuit, the original signal for transmission is restored, and the signal mixing circuit 152
is input to the handset of the telephone unit 101 via the receiver. Thus, a call is started between the mobile radio device 100 and a regular telephone within the regular telephone network 10 <3225>.

An example of the signal format in the time slot during a call, when transmitted by the wireless base station 30-1, is as follows:
It is shown in FIG. 20(a). In the same figure (a), the call signal does not use all the time slots, but is accommodated in the part indicated as communication (talk) information, and the other parts are the base station ID, the opposing Mobile radio 1100 in communication
ID of.

It includes traffic information, etc. in that wireless zone. The call quality when this signal is received by the mobile radio device 100 is monitored by the call quality monitoring unit 157, and if the following conditions occur, the time slot is changed as the call quality is degraded. It turns out.

They are > when the noise level is increased compared to the signal.

ii> Is the base station ID shown in Figure 20 unreceivable?
Or when receiving the base station ID of a third party with which you are not communicating.

In case 11 of the above, another mobile radio m1oo that happens to be in the vicinity is also making a call during the calling operation, and it is the gateway exchange I! 120, the communication was started using an empty time slot with the same number as the nearby wireless base station 30, causing radio interference, or the mobile wireless m100 moved during the call, so that when the call started, Either the interference did not occur, but it started to occur during the process. Therefore, the time slot switching operation during a call, which will be explained in the section (4) Time slot switching operation during a call, is performed. In addition, in FIG. 21-1, illustration of the synchronization signal is omitted.

Furthermore, in the above description, if it is desired to always receive the base station ID, etc., a signal format as shown in FIG. 20(b) may be adopted. Although it is necessary to slightly reduce (or speed up) the communication information accommodated in one time slot, this is the method of providing blank time as described in FIG. 2G. As a result, time slot switching, which will be described later, can be realized in accordance with the monitoring results of the speech quality monitoring section 157 without the adverse effects described in ii>.

The call is terminated by turning on the receiver of the telephone section 101 of the mobile radio 100 (3226), and the end of the call signal and the on-hook signal from the control section 140 are transmitted to the speed conversion circuit 1.
31 from the wireless base station 30- from the wireless transmitting circuit 132.
1.30-2 (8227>), the control unit 140 stops the operation of the transmission/reception intermittent control unit 123, and switches 122-1 and 122-2 to the output of the local oscillator 121-1. It is fixed at the end and the open end and enters the state of waiting for reception.

On the other hand, when the control unit 40 of the radio base station 30-1, 30-2 receives the clearing signal g from the mobile radio 100, it transfers the clearing signal to the gateway exchange 20, and switches the switch 5WR1- of the switch 1f83. 1,5 WT1-1 is turned off to end the call (S228.5229>. At the same time, the wireless base station 30
-1.Signal selection circuit group 39 in 30-2 (39-1)
and opens the bow allocation circuit u5'2 (52-1>).

In the barrier exchange 1!20 that receives this call termination signal, the switch group 23 is turned off and the call is terminated (S230> In the above explanation, the communication between the wireless base station 30-1. or 30-2 and the mobile radio device 100 is Although it has been explained that the control signals are not exchanged through the signal speed conversion circuit group 51, signal speed restoration circuit group 38, etc., this is for convenience of explanation, and the exchange of control signals between the signal speed conversion circuit group 51 and the signal speed restoration circuit group 38 is done for convenience of explanation. , communication can be carried out without any problem even through the signal speed restoration circuit 138 or the signal processing section 31.

(3) Incoming call operation The incoming call operation to the mobile radio 1100 will be explained using the flowcharts shown in FIGS. 68 to 6D.

It is assumed that the mobile radio device 100 is on standby with the power turned on. In this case, the mobile radio device 100 has already completed location registration and is in a state of waiting for incoming calls except when making a call itself. In this state, the mobile radio device 100 is waiting for a signal transmitted from a nearby radio base station 30.

In the system of the present invention, since there is only one radio channel, (the radio base station 30 transmits, the mobile radio tal
00)) will be held in an empty time slot on the downlink channel. Specifically, for example, the following method is used.

That is, starting from time slot number 1 within one frame, 2, 3, and so on. . . . sequentially searches for vacant time slots, and serves the time slot (for example, 5D1) according to the instruction of the control signal contained therein. Also,
Unless otherwise instructed, the samurai will receive the lowest numbered time slot.

By any of the above methods, if the time slot to be received in the radio channel transmitted from the radio base station 30 is SDl, the local oscillator 121-1 generates a local frequency that enables reception of the radio channel. The switch 122-1 is also in a fixed state with the local oscillator 121-1 side turned on.

Under the above conditions, the mobile radio device 100 is sent from the general telephone network 10 to the gateway exchange 20 via the exchange ell.
Suppose there is an incoming call addressed to the user. In the barrier exchange R20, when the IDI-specific storage unit 24 is searched, it is recognized that the mobile radio device 100 is currently registered in the location of the radio base stations 30-1 and 30-2, so the incoming call to the mobile radio device 100 is Prepare to send the signal. That is, the traffic within the radio base station 30 that is in charge of communication.

Determine by considering signal quality etc. at the time of location registration. As a result, when the radio base station 30-1.30-2 is determined to be in charge of communication, the mobile radio 1100 uses the empty time slot SDI held by the mobile radio 1100 to select the radio base station 30-1.3.
An incoming call signal is sent to 0-2 (S251, Fig. 6A).

At the radio base station 30-1. to control 81S40 (FIG. 1C).

Then, the m control unit 40 controls the communication path control unit 81 to control the transmitting and receiving switches SW of the switch group 83;
Check the switches that can be used as SWRs and instruct them to keep them in the on state.

Further, the signal is transferred to the mobile radio device 100 in the method instructed by the gateway exchange 20 (3252°3253>).

This method includes, for example, wireless base stations 30-1 and 30-2.
use term slot SD1 at the same time and transmit the same signal. The same signal includes, for example, the ID signal of the mobile radio device 100 and the incoming call signal display signal. Although the above explanation has mainly concerned the radio base station 30-1, similar operations are also performed in the same <30-2.

In the mobile radio device 100 that received this signal, the receiving section 137 of the front receiving circuit 135
0. 1tiil 1C unit 140 confirms that this signal is an incoming call signal to its own mobile radio device 100 <3254>, and sends time slot SU1. to radio base stations 30-1 and 30-2, respectively.
Use SU2 to move vJ, v line + 1” + 00 own ID
is sent back as a response confirmation signal (3255).

Now, the radio base station 30-1.30-2 that received the incoming call response signal from the mobile radio 11"+00 confirms the ID,
A quality check is performed (3256, 3257), and an incoming call response signal is sent to the barrier switch 20 along with these data (
S258,5259:),,.

By the way, the call response signal sent from the mobile radio device 100 may not necessarily be received by the radio base station 30-1 or 3O-2 (Ekari), but may also be received by other nearby radio base stations 30-3, etc. Alternatively, if the mobile radio device 100 does not update the location registration for some reason after completing the location registration, the radio base station 30-1. There are cases where the reception is good at the base station 30, etc. In other words, the surrounding wireless base stations 30 constantly monitor empty time slots, and if a call is made or received from the mobile wireless device 100, This is because the system is designed to immediately take necessary action when a call response signal is successfully received.
As one of these measures, in the case of the above-mentioned incoming call response signal, the gateway exchange 20 is notified of this.

Due to the system operation described above, the incoming call response signal to the barrier switch 20 may include the ID of the unregistered wireless base 830 in addition to the ID of the mobile wireless device 50. When this incoming call response signal is received, the barrier switch 20
Then, it is confirmed whether or not the rD of the mobile radio device 100 is already stored in the ID identification storage unit 24. If it is not stored, the rD is stored in the ID identification storage unit 24 together with the quality inspection data of the wireless base station 30. and use this memorized ID.
Along with this, a location registration signal is transmitted to the wireless base station 30-3 and the like. The subsequent operations are the same as those of the wireless base stations 30-1 and 30-2 whose locations have been registered.

Now, returning to the main topic, the gateway exchange 20 that has received the incoming call response signal from the plurality of wireless base stations 30 confirms the ID (8260>, communication sazeru p!, the base station 30, time slot used, etc. are determined, and each wireless base station 30
-1.30-2 (S261, Fig. 6B).

At the radio base #30-1 etc. that received this signal, mobile radio m1oo's 1. 3262, 5263> to confirm that D has been correctly registered to B, check whether the time slot specified by the gateway switch 20 is vacant, and consider whether or not to switch 8264, 3265). A certain time slot designation signal is sent to the mobile radio device 100 using the downlink time slot SD1 (S266.
8267).

This time slot designation signal was received (S268>
, when the mobile radio m100 confirms that the specified time slot is an empty channel (S26
9>, it switches to that time slot and sends a time slot switching completion report using time slot SU1 of the uplink radio channel (3270, FIG. 6C). Responses to time slot designation signals sent from other radio base stations 30 are also similar to the above.

Verified that it was switched to a free time slot (
3271.3272>The radio base station 30-1 etc. also switches its own station's transmission and reception to this time slot and uses the time slot.
A slot switching completion signal is sent to the barrier exchange 1120 (3273.3274).

When the barrier exchange R20 receives the time slot switching completion signal, it operates the communication path control unit 21 to set the communication path to the telephone wJlo via the exchange 1"l'l, and switches the switch group 23 appropriately. The switch SW is turned on to connect the wireless base stations 30-1 and 30-2 to the telephone network 10 (8275>. Then, a calling signal is sent from the telephone network 10 side via the exchange 11 and the gateway exchange 20. (32
76>, this is confirmed by the radio base station 30-1.
79,5280>, the mobile radio IJloo generates a ring tone (3281).

As a result of this ringing, the handset on the mobile radio 100 side is lifted (off hook) (8282, Fig. 6D)
, an off-hook signal is sent to time slot 1 at sul and su2, transferred by radio base station 30-1, 30-2 (8283, 3284), received by gateway switch 20 (3285>, Group 23 switch 5W1-
1-1.2-1-1 is on, and the time slot SD between mobile radio m100 and radio base Q30-1 is on.
"l, SUL, downlink frequency F1, uplink frequency fl, time difference between mobile radio device 100 and radio base station 30-2.
Slot SD2. S2. Downlink frequency F1. A call is started between the telephone network 10 and the mobile radio device 100 using the upstream frequency fl (3286).

When the call ends, the handset is put down, and the on-hook signal and end-of-call signal are transmitted to the wireless base station 3 by SU1 and 5tJ2.
0-1.30-2 (S287), and the radio base station 30-1.30-2, which confirms the end of the call, transfers this signal (8288.8289>.This on-hook signal and the end of the call The barrier switch 20 that received the signal transmits the communication control unit 2
1 and turns off the switch SW in the switch group 23 that has been used so far to end the call (3290>).

In the above explanation, time diversity using two time slots was applied.

However, this diversity is not necessary; for example, in cases of heavy call traffic, the use of only one time slot may be sufficient.

The operation in this case will be explained based on the above explanation.
It is sufficient to leave the communication with mobile radio device 100 related to radio base station 30-1 and delete all the explanation related to radio base station 30-2.

(4> Time slot switching operation during a call Mobile radio 10
0 as cars and pedestrians move, the wireless base station 30
-1. When communicating with 30-2, wireless base station 30-
The operation when switching time slots so as to communicate with 3 will be explained. Among these, there is also the fact that there is no instantaneous interruption due to time slot switching, which is a feature of the present invention.
This will also be explained.

The mobile radio FMloo uses a local oscillator 121-1, a radio receiving circuit 135, and a radio transmitting circuit 132 to communicate with radio base stations 30-'I and 30-2, and transmits time slots upstream SUL, SU2, and downlink SD1, respectively.

Assume that communication is in progress using 3D2. Mobile radio device 100
moves away from the wireless base station 30-1 and becomes a wireless base [3
Let's say it's close to 0-3. Then, as the relative distance between the mobile radio device 100 and the radio base station 30-1 increases, the call quality begins to deteriorate. The S/N monitoring unit 25 detects quality deterioration of the transmission signal from the radio device 100.
(detects that the level has fallen below 1).

Note that even if the level is 1, the line is set to exceed the required value. All nearby wireless base stations 30 are requested to measure the quality of the transmitted signal from the mobile wireless device 100.

In response to this request, each radio base station 30 sends the measured value to the barrier exchange 20, so the S/N monitoring unit 25 of the barrier exchange 120 starts comparing it with level 2 of the communication quality standard. As a result of the comparison, the measurement result of the wireless base station 30-2 has the best value, and the quality standard level is 2 or higher, but 12
If it is confirmed that >11 is satisfied, the mobile radio device 100 determines that the mobile radio device 100 has moved to the communication zone of the radio base station 30-3 (Zone 3), and decides to perform time slot switching. Then, as a result of investigating whether or not there is a vacant time slot in zone 3, it is found that the vacant time slot is usable.Then, the time slot S of the downlink radio channel currently in use is found to be available.
The mobile radio 110 is controlled by control signals using DI and SUI.
0, time slot SD3. Instructs SU3 to prepare for transmission and reception.

At the same time, a time signal is sent to the wireless base station 30-3.
Slot SD3. Instructs SU3 to perform transmission and reception. In the barrier exchange 120, after issuing these instructions, the switches 5W1-1-1, 2-1-1 and 5 of the switch group 23 are
W3-1-1 and wireless base station 3 are turned on at the same time.
0-3 as well, the transmission of the same call signal as that for radio base stations 30-1 and 30-2 is started. Naturally, the modulation depth of the modulators of the three radio base stations 30-1, 30-2, and 30-3, the length of the time slot, 1
The number, timing, etc. within a frame are also the same.

In order to realize the transmission of this control signal, specifically, when the control signal is an analog signal, as shown in FIG. Lower frequency fDo (e.g. about 100 days 2) outside OK day Z or higher frequency f[)1 = fD2 = fD3”” DB (e.g. 4.5KH2 with days 2 interval from 3.8KH2 to 0.1)
(up to 8 waves) are used.

When there are many items to be controlled, that is, a large number of control data, the wave number of the control frequency fDo"" fD8 may be increased roughly, or a subcarrier format may be used. At this time, more control data can be transmitted by, for example, applying frequency modulation or amplitude modulation to one or more waves of fDo""fD8.

Furthermore, when a digital data signal is used as a control signal, it is also possible to digitally encode the audio signal and time-division multiplex the two to be transmitted.
This is shown in Figure E (b). FIG. 2E(b) shows an example of a case where an audio signal is digitized by a digital encoding circuit 91, and the audio signal is multiplexed with a data signal by a multiplex conversion circuit 92, and then applied to the modulation circuit of the transmitter 31.

FIGS. 2C and 2D show timing charts before and after channel switching in this system.

In FIG. 2C (C) or (d), the downlink time slot SD1 or SD2 is the radio base station 30
-1 or 30-2 is the time slot used as a transmission signal addressed to the mobile radio device 100, and other time φ slots include empty slots used for other mobile radio devices) shall be. Similarly, in FIG. 2C (e), it is assumed that time slot SD3 is used as a transmission signal addressed to mobile radio device 100 by radio base station 30-3 with which communication is to be newly attempted.

In addition, <t'>, (c+), and (h) in Figure 2D are
These are signals transmitted from the opposing mobile radio device 100 after receiving the outputs of (C>, (d>, and e) in FIG. 2C, respectively. Therefore, the time slots used are StJ"l , 5tJ2.SU3, and the others are used for other communications (including empty slots).

In FIG. 2C (C) and FIG. 2D (f), the quality of the time slot SD1.SU1 used between the radio base station 30-1 and the mobile radio device 100 has decreased to a level of 1 or less. The S/NU viewing unit 25 of the barrier exchange v120 detects the
Using time slot SD1, the mobile radio device 100 is instructed to start preparing to be able to receive the radio waves transmitted from the mobile radio device 100 in parallel.

Therefore, the control unit 140 of the mobile radio 111100 uses only the local oscillator 121 until then to set the time slot SD1. and time slot SD3 transmitted from radio base station 30-3 from the state in which SD2 is receiving transmission waves from radio base stations 830-1 and 30-2.
Make preparations to be able to receive the transmitted waves as well.

When the radio base station 30-3 emits 9A of transmission waves in time slots 1 to SD3 due to the quality degradation of the time slot SD1 being transmitted from the radio base station 30-1, the mobile radio 100 performs transmission/reception. The intermittent controller 123 is operated to repeatedly switch the changeover switch 122-1. At the same time, time slot SU1. Transition from a state in which transmission was being made to the wireless base station 30-1 and 30-2 using time slot SU2 to a state in which transmission can be made to radio base station 30-3 in time slot SU3. let The output of the local oscillator 121-1 used for this transmission is also repeatedly switched by a signal from the transmission/reception intermittent controller 123 by the changeover switch 122-2.

Time slot SU1,5tJ2. This switching transmission/reception period in which time slots SU3 are transmitted and received in parallel continues until the barrier switch 20 confirms that the quality of time slot SU3 is at a certain level 12 or higher, and then time slots SD1. Release SU1 and connect wireless base station 30-
Communication between SD2.2.2.30-3 and mobile radio 100 takes place in time slot SD2.2.30-3 of channel CH2. SD3. SU2
゜It continues without momentary interruption only by SU3.

The switching frequency fl of the changeover switches 122-1 and 122-2 during this switching transmission/reception period is a value determined for each system, where n is the number of time slots in a 171 norm, and T1 is the time interval between one time slot. Then, it is given by 1 f = (nT1).

FIGS. 78 to 7D show flow charts showing the flow of operations when switching channels during a call in this system.

Gateway exchange 20. Wireless base station 30-1.30-2.30
-3 and mobile radio l1100 start operating, and switch 5W1- of switch group 23 included in barrier switch 20
1-1.2-1-1 is on, and the wireless base station 30-1
．． 30-2 and mobile radio 1100 are communicating.

For this communication, the communication control unit 2 included in the barrier exchange 120
The time slot indicated by SD1.1. SD2
゜SUl, SU2. Downstream frequency Fl and upstream frequency fl are used (S101, Fig. 7A).

The wireless base stations 30-1 and 30-2 that are in communication constantly issue reception status reports from the mobile wireless device 100 (810).
2>, S/N monitoring unit 25 of barrier switch 20 receives this
, the call quality is monitored to see if it has deteriorated beyond level 1 (S103).
(3103YES), the communication control unit 21 sends a request to the wireless base station 30 in the vicinity of the wireless base station 830-1 to communicate with the wireless base station 30-1 and the mobile wireless device 1.
It instructs to monitor and receive the signal of up frequency rl and time slot SU1 used for communication with 00 (3104).

Each of the surrounding wireless base stations 30 that has received an instruction to monitor reception (for example, 30-3> monitors and receives signals of s, t, frequency f1, and time slot 5tJ1 5105), transmits the results to the S/S of the barrier exchange 120. Report to N monitoring department 22 3
106) Measure and compare the monitor reception quality from each radio base station 3O, and detect that, for example, the call quality of the radio base station 30-3 is better than the fixed standard level 2 and is R-good (3107YES> .

Therefore, the communication control unit 21 allows the mobile radio l1100 to move from the zone covered by the radio base station U30-1 to the radio base station 30-1.
310 because it seems to have moved to the zone covered by 3.
8. FIG. 7B> Search for an empty time slot that can be used by the wireless base station 30-3 in order to switch to communication with the wireless base station 30-3 (3109), and as a result, the time slot SD3 ．． Determine SU3 (311
0). The communication control unit 21 causes the control unit 140 to transmit time slot SD3. A command is given to make Q-preparations for communication at SU3 (S111).

This time slot SD3. A communication preparation command for using SU3 is sent to the radio base station 30-3, and the time
Prepare for communication using slots SD3 and 5tJ3 (3
112>. This command is simultaneously transmitted from the radio base station 30-1 in time slot SU3 (8113).

Mobile radio 100 uses this time slot SD3. S
, U3, please receive the communication preparation command on frequency Fl S]
14), time slot SD3. Preparations for enabling communication by SU3, that is, receiving frequency Fl from control unit 140 to local oscillators 121-1 and 121-2, maintaining a state in which transmission can be performed at frequency fl, and transmitting/receiving The intermittent controller 123 controls the time slot SD
3. The operation using SU3 begins (3115, Fig. 7C).

Time slot SD3. When ready to communicate using SU3, mobile radio 1100 reports completion of preparation to radio base station 30-3 using time slot SU3 <3116>.

Upon receiving this report, the wireless base station 30-3 performs step 51.
After confirming the completion of preparation in the radio base station 30-3 by the time slot SU3゜SU3 prepared in step 12, the barrier exchange 1 is performed.
Report to 20 (3117) Time slot SD3
．． Radio base station 30-3 and mobile radio device 1 using SU3
When the barrier exchange R20 confirms the completion of communication preparation with 00 (S118), the switch 5W1 of the switch group 23
-1-1. Leave 2-1-1 on and switch 5
W3-1-1 is also turned on (S"119).

Therefore, the communication control unit 21 included in the barrier switch 20 transmits time slot SD3. Instructs to start communication using SU3 (8120). Upon receiving this communication start command (S121), base station 30-3 sends a communication start command using time slot SD, 3. (S122>. The mobile radio 1100 confirms the start of communication in time slot SD3.SU3 using the ID signal which is an identification signal for identifying the mobile radio 512.
3) Sends a communication signal including an ID signal using time slot SD3. S
U3 reports that communication has started (3125>).

Upon receiving this report, the S/N monitoring unit 25 of the barrier switch 20 selects time slot SD3. To confirm the start of communication by SU3 (5126), the mobile radio device 100 and the radio base station 30
-3, and if it is detected that the quality level is 2 or higher (S127YES)
, FIG. 7D〉, Radio base station 30-1 and mobile radio ll00
(B) Time slot S01. The wireless base stations 30-1 and 30-3 are instructed to stop the communication that was being performed using SU1 (8128).

As a result, the radio base station 30-1 turns off communication using time slot SD1.5tJ1 (S129>
. Also time slot r-3D1. The wireless/wireless base station 30-3, which received the command to stop communication from SU1, forwards the command to this time slot S01.
．． When the mobile radio l1100 receives the command to stop communication from S1 (3131>, the changeover switch 122-2 continues to turn on and off at a predetermined timing, and
Slot SD2. SD3. SU2. Only S3 is activated, and a communication stop report in time slot S1 is sent using time slot SU3 (S
”132). Upon receiving this, the radio base 830-3 transfers the communication stop report for this time slot 5tJ1 (3133).

Upon receiving the communication stop report from time slot SU1, the communication control unit 21 of barrier exchange [20 leaves the switches 5W2-''I-1, 3-11 of the switch group 23 on, and
Switch 5W1-1-1 is turned off (8134).

As a result, the period of time slot switching operation ends, and the downlink frequency fiF1. Using the upstream frequency fl, the mobile radio device 100 can continue communication with the radio base station 30-2, 30-3 without momentary disconnection or noise mixing (3135>).

In the above explanation, there is only one wireless channel used in the system of the present invention, so even when switching wireless channels during a call, it is important to remember that the same wireless channel is used between adjacent zones. This was explained as a premise. This is because when time-division communication is performed as in the present invention, even if the same radio channel is used in two adjacent zones in a small zone method, the system does not transmit radio waves in empty time slots, or it may not transmit radio waves. In both cases of the system, the system transmits the cell 1-content signals at the same timing: 1. As already mentioned, since there is no risk of radio interference occurring, it is possible to use the same radio channel.

(5) Transmission/reception diversity performed between multiple wireless base stations Figures 88 to 8D show flowchart 1 showing the flow of operations when transmitting/receiving diversity of this system is executed. has been done.

Gateway exchange 20. The radio base station 30-1.302 and the mobile radio device 100 start operating, and the switch 5WI-1-1 of the switch group 23 included in the barrier exchange 120 is on, and the radio base station 30-1 and the mobile radio device 100 start operating. Communication is in progress with 100. For this communication, a wireless channel CH instructed by the communication control unit 21 included in the barrier exchange 20 is used.
'l time slot SDI, SU1. Downlink frequency F
l and upstream frequency fl are used (3301, 8th A
figure>.

It is assumed that the mobile radio device 100 continues to communicate with the radio base station 30-1 and decides to perform transmission/reception diversity with other nearby radio base stations 30 in order to maintain or improve communication quality. (S302>. This determination is sent to the wireless base station 30-1 by an out-of-band control signal (
303), the radio base station 30-1 receives this 304
), the signal is transferred to the gateway exchange 20 (3305>).The barrier exchange 20 that received this signal (3306) searches for the communication traffic situation in the vicinity of the mobile radio device 100 (S3
07). As a result, if abnormal traffic congestion is found (3308YES>), the radio base Ji instructs the mobile radio m1oo to disable transmitting/receiving diversity.
a30-1 (3309>. Also, if there is no comparison with the tiger (3308NO>), the wireless base station 30
-1, wireless base station 3
0-1 and the mobile radio 11100 to monitor and receive the signal of the time slot 5U2 used for communication (S310, FIG. 8B).

Each of the surrounding radio base stations 30 (for example, 3O-2) that received the instruction to monitor reception monitors and receives the signal of time slot SU'l (5311), and sends the result to the S/N monitoring 8+522 of the gateway switch 20. Report 5312, 53
13>, measure and compare the monitor reception quality from each wireless base station 30, and detect that, for example, the call quality of wireless base station 30-2 is better than Level 2 under a certain standard.<3314
(YIES) Therefore, the communication control unit 21 uses the mobile radio tfl'
It is determined that lo○ has moved from the zone covered by the wireless base station 30-1 to the zone covered by the wireless base station 30-2, and in order to implement transmission/reception diversity with the wireless base station 30-2, the wireless Search for free time slots that can be used by base FE630-2 5315
), resulting in time slot SD2. Determine SU2 (3316). The communication control unit 21 transmits time slot SD2. It also operates SU2 and instructs it to prepare for communication based on transmitting and receiving diversity (5317).

This time slot SD2. A communication preparation command for using SU2 is sent to the radio base station 30-2, and the time
Slot SD2. Prepare for communication by SU2 (33
18). This command is simultaneously sent from the radio base station 30-1 using time slots 1 to SDI (3319).

Mobile radio 100 uses this time slot SD2. S
Receive a communication preparation command by transmitting/receiving diversity using U2 as well.S320>, time slot SD2゜5
Preparation to enable communication including tJ2, that is, the transmission/reception intermittent controller 123
．． The operation starts using SU2 together (S321).

Mobile radio 130-'l and time slot SD1°5t
While communicating using J1, time slot [・SO2
, 5tJ2, the mobile radio 100 sends a report of completion of preparation to time slot 5U2.
-2 to report to wireless base station 3/O-2 (
3322). The radio base station 30-2 that received this report,
Time slot SD2. prepared in step 5318.
'ofi indicates the completion of preparations within radio base 8302 by SU2.
= and sends a report to the gateway exchange 20 (3323).

Time slot SD2. When the gateway exchange 20 confirms the completion of communication preparation between the radio base station 30-2 and the mobile radio 1100 using SU2 (S324), the switch 5W1-1-1 of the switch group 23 is left on. hand,
The switch 5W2-1-1 is also turned on (S325). Therefore, the two communication system vlA sections included in the Kanmon Traffic Inspection Line 20,
Radio base station 30-2 communicates with mobile radio 11100 in time slot SD2. A command is given to start communication using SU2 (3326, FIG. 8D).

Upon receiving this communication start command (3327), the radio base station 30-2 transmits the communication start command using time slot SD2 (S328). The mobile radio device 100 receives the time slot SD2. The wireless base Q30-2 confirms the start of communication by SU2 (3329) and sends out a communication signal including an ID signal using time slot SU2 (3330). SU2 reports that communication has started (3331).

Upon receiving this report, the S/N monitoring unit 25 of the barrier exchange 120 selects the time slot SD2. To confirm the start of communication by SU2 (5332), the mobile radio device 100 and the radio base station 30
-2 and detects that the quality level is equal to or higher than a certain quality level 2 (S333YES)
.

As a result, the transition period to the transmitting/receiving diversity operation is completed, and with the switches 5W1-1-1 and 5W2-1-1 in the on state, the transition to the wireless base station 30-1 is completed in step 53.
In the state at 01, the mobile radio device 100 can continue communication with the radio base station 30-2 using transmitting/receiving diversity (8334).

In this transmission/reception diversity communication, the switches 5W1-1-1 and 5W2-1-1 of the switch group 23
Both radio base stations 30-1 and 30-2 are in the on state, and the same call signal as that of radio base station 30-1 is sent to radio base station 30-2.
-2 modulator modulation depth, time thrower [
・Length.

The number, timing, etc. within one frame are also the same.

(6> Comparison of the diapersity effect according to the present invention and the conventional method. Figure 9 shows the diaperity effect according to the present invention and the conventional method.
A comparison with +a transmission angle modulation or amplitude modulation method is shown below.

First, in the transmission/reception diversity using multiple wireless base stations 30 explained in (5), it is possible to implement it in multiple wireless base stations 30, and if the receiver is equipped with the function, it can be used similarly. It is possible to communicate using the same time slot or using separate time slots, and a diversity effect can be obtained. Roughly speaking, since these radio base stations 30 are located at different locations, It is clear that there is no cross-correlation in the transmission and reception characteristics between the antennas, and that a diversity effect can be obtained.

Next, in transmitting and receiving diversity using the same radio base station 3Q according to the present invention, since the locations are the same, the diversity effect cannot be obtained if the same channel and the same time slot are used. In space diversity, unless the transmitting and receiving antennas are separated by an appropriate distance, the correlation coefficient between the antennas will not approach zero and a satisfactory effect will not be obtained.

On the other hand, in the conventional method, when multiple radio base stations are used, the space diversity effect can be obtained on both the same channel or different channels, but the space diversity effect can be obtained for each time slot. Since it is impossible to achieve this, naturally the diaperity effect cannot be obtained. Furthermore, if the same radio base station is used, although there will be some space diversity effect, it will not be possible to use the same channel, the same time slot, or different time slots.

From the above evaluations, it has become clear that the transmitting and receiving diversity according to the present invention is economical and has great effects. Furthermore, the configuration of mobile radio device 100 can be simplified. A mobile radio device 100B having such a configuration is shown in FIG. 1D. Although FIG. 1D is equipped with only one pair of transmitting and receiving radios, it is clear that transmitting and receiving diversity can be implemented with the configuration shown in the figure as long as the same radio channel is used. Dew.

In addition, three or more different wireless base stations 3Q and mobile wireless INl
00B, using many time slots,
It will be easily understood from the above description that transmit/receive diversity can be implemented.

(7) Detailed Description of the Present Invention Next, we will theoretically explain how this system can be used to perform signal transmission in good conditions without adversely affecting other wireless channels within the system. for that,
Let us take an example of an uplink (transmitted by mobile radio device 100, received by radio base station 30) radio signal.

First, assume that all uplink radio signals are empty lines, that is, no time slots are used. The mobile radio IX1100 that wishes to make a call receives a control signal in the downlink radio channel, for example, in time slot SD1.
When the mobile radio device 100 has selected an available time slot (for example, time slot SDI>) of an uplink radio channel, a control signal (a communication path is set) is sent from the radio transmission circuit 132 in response to a signal from the timing generation circuit 142. A call signal> is sent to the wireless base station 30.

Similarly, if there is a call originating (terminating) from another mobile radio, an IIII control or conversation signal is sent to the radio base station 30 as an uplink radio signal using another time slot on the same radio channel.

The signals included in the uplink radio channel explained above will be expressed mathematically.

The output signal g (or control signal) of the telephone section 10''l of FIG. 1B-1, the data or speech signal (for signals in analog or digital format), can be expressed as follows.

μ(1)=, Σa・cos (ωH 1θi〉!=11 (1) Also, the control signal that exists outside the band is μ.B)=, xiHcos(mi(+θj)(2〉) where , a・ is the magnitude of the amplitude, ω・ is the angular frequency of the signal,
θ· represents the phase when 1=0. m.

n represents a positive integer.

Next, the case of frequency modulation will be explained, but the present invention is similarly applicable to both phase modulation and amplitude modulation. When a carrier wave is frequency modulated using equation (1) or equations (1) and (2), the resulting modulated wave is I=IoSinf(ω+μ(t))dt=Iosin(
If ω is 15(t)> (3) or ! = I□ 5iri f (ω10μ(1)10μ.Ct
)) dt=I□5in(ωt+5(t)+5o(t))
(4) However, mi = ai /ωi (i=1.2, 3...,
n) S (t+ −F S c (
t) will represent the general form of the transmission signal.

Now, using equation (3> or (4)), the radio signal sent out from the antenna of mobile radio device 100 is expressed by the following equation.

1=(101/n> [1+222 (n/rnyr
>) m=1 XSln (m7r/n)CO3mpt]xs+n
(Ω1t+51(1)+5c1(t)) (5) where n is the number of slots (equal time intervals) within one frame, p is the switching angular frequency, and m is a positive odd number.

Equation (5) is the mobile radio device 10 using the same radio channel.
The transmission signal from 0 is in the back of slot 1-n in one frame, but when all slots are filled with signals, that is, n mobile radios 1100 are using the same radio channel. The mathematical expression of the signals included in the wireless channel when the wireless channel is in communication is as follows.

1= (I01/n) [1+2F1(n/mπ〉)x
sin (myr/n) cos mp t ]
x sin (Ω j 1 S 1 (i) + S cl
(1)) ten (I02/n> [1+2Σ (n/mπ> m=1) xsin (myr/n) xcos mp (t-2π/ (np)) ]xsi
n (Ω2 j+S2 (t) +5o2(t) )(
103/n) [1+2Σ (n/myr> ) m=1 xsin (myr/n) xcos mp (t-47C/ (rl))] xsi
n (Ω3 j+S3 (t) +5o3(1)>+
(I□n/n) [1+2mo(rl/mπ))
xs+n (mπ/n) XCO3rrD) (t-2(n-1> 7m/ (n
D>) ]xs+n (Ω t+s, (1) ten S.,
(1) ) <6> However, p is the switching angular frequency, m is a positive odd number, and the switching times for n input waves are equally spaced.

The radio signal transmitted from the radio base station 30 in FIG. 1A is
(This will be expressed by equation 6, and the mobile radio device 100 communicating face to face uses the timing generator 142 shown in FIG. 1B-1 to generate only the signals necessary for itself in equation <6>). Selective reception is performed using the transmission/reception intermittent controller 123. Now, if this is the time slot SD'l shown in FIG. 2A for the mobile radio device 100-1, (6)
This is the first term on the right side of the equation, that is, the signal shown on the right side. When the equation (5) passes through the amplitude limiter included in the receiving section 137 in FIG. 1B-1, it takes the form shown in the equation below.

1=Asin (Ω1 151(t) +s.1(t)
)<5') However, A is the amplitude and is not related to frequency or time.

When equation (5') passes through the same wave number discriminator included in the receiving section 137, the demodulated output is e (t) - μ (1) 10 μ. (1) Obtain. Then, by passing this output through the speed restoration circuit 131 shown in FIG. 1B-1, the original signal is reproduced.

The case where the radio base station 30 transmits and the mobile radio 100 receives is explained above, but the case where the mobile radio 100 transmits and the radio base 830 receives is also explained in the same way. However, in this case, instead of receiving only the required signals for the mobile wireless device 1o○ itself as in the case of the mobile wireless device 100, it receives all the signals 8 sent in chronological order from a large number of mobile wireless devices 1100. The difference is that you have to pull it. .

Hereinafter, equation (6) will be modified as it will be necessary to investigate the influence of adjacent channel interference, etc.

The right side of equation (6) is expanded as shown below.

I= (Iot/n > [s+n (Qlt +U
1 (t) )+〈n/π) sin(π/n) X[5in((Ω1+D) 'j + ul(1)
)+sin ((Ω1-p)t+u1(t)) ]+
(n/3π〉sin (3π/n)x) sin((
Ω1+ 3 p) t +U 1 (t)-(6π/n
)(n-1)) +5in((Ω1 3p) t+tJ1 (1+(6π
/n) (n-1>)] + (n15yr) sin (5π/n)X[5in
((Ω +5D)t+U1(1)-(10π/n)(n
-1)) 15in ((Ω1 5p)-j+U1(1)+(10π
/n＞(n−1))] +・・・・・・ ]+(I
02/n> [sin (Ω2t+L12 (t))
+(n/π) sin(π/n> x[5in((Ω2 +p) t +LJ2 (t)
)+5in((Ω2 D) t+U2 (j) )
] + (n/3yr) sin (37r/rl) x [
5in((Ω +3p> t+IJ2 (1)-(6π
/n>(n-1>) +5in((Ω2-3p)t+su2(t)+(6π/n
>(n-1))] + (n15:yr) sin (57r/n>x[5
in((Ω +5p> t+U2 (t)−(10π/
n>(n-1>) +5in((Ω2 5p) 1:+U2 (t)+(1
0π/n>(n-1>)] −←・・・・・・
1+ (10n/n> [sin (Ω, t+Uo(t
))+(n/π)Sin(π/r+)X[5in((Ω 10p)t+Uo(t))+5in(
(Ω − p ) t + U n (t) ) ]] + (n/3yr) sin (3yr/n) x [5i
n((Ω +3p)t+Un(1)-(6π/n>
(n-1>) +sin ((Ω-3p)t+tJn(t)-(6π
/n>(n-1))] + (n15yr) sin (5yr/n>x[5i
n((Ω +5p)t+s.(1)-(10π/n>(
n-1>') +5in((Ω-51))t+Uo(t)-(10π
/n)(n-1>)] (7) However, u・(t)−s・(t)+5cH(1)+
+ (i=1.2..., n) Here, looking at equation (7), it can be seen that it is a combination of many carrier waves.

Below, we will quantitatively evaluate interference with adjacent wireless systems, co-channel interference, and delay time of transmission and transmitting stations, which are problems in system construction, and explain that the system according to the present invention can be operated without any problems in practice. .

(1) Interference with adjacent wireless systems Taking as an example a case where the number of time slots in one frame is 10, the audio multiplicity is 10.1, and the frame period is 100 msec, the calculation results show that most of the signal components It was found that 1q stays within one channel and ignores the influence on adjacent wireless systems. Also, if the system
Depending on the parameters, if this becomes an influential factor, it can be ignored by inserting a bandpass filter in the transmission output stage.

(II) Self-intra-channel interference Self-intra-channel interference occurs because of the characteristics of the bandpass filter or intermittent circuit set at the output section of the wireless transmission circuit, and the higher-order wave of the transmitted pulse, that is, the carrier frequency, is Ω1. This is because carrier waves having a large value of n out of ±np are not output. In this case, the ideal shape of the envelope of the signal wave sent out into space is not a rectangle (within which the carrier wave is accommodated), but ultimately a number of sine waves approaching a rectangular wave. The waveform has a superimposed shape (the waveform is the 2nd B
(The state has a beat-shaped envelope as shown in d>).

Then, a signal component with this shape will enter another time thrower 1, causing self-intrachannel interference.

This influence will be theoretically determined below.

Assume that time slots SD1 and SC2 are used for communication A and communication B (FIG. 2B (d)). The interference waves that influence communication A on communication B can be expressed numerically with reference to equation (7) as shown in the following equation.

xsin ((2m+1) π/n) [cos
((Ω+ (2m-+l)to)t+U(t))
-COS((Ω-(2m+1)p)t +U(t))Co(9) Equation (9) can be specifically determined by calculating an approximate value from Equation (7). . The result is
Taking the characteristics of the filtering circuit included in the wireless transmitting circuit 32 into a wide band, m□ is, for example, too (100H
zx tooo-100KH2) or more, it becomes possible to ignore the influence of self-channel interference. In an actual circuit, this condition can be easily satisfied.

■〉 Co-channel interference Co-channel interference occurs when the present invention is applied to a small zone system, when a time slot in use in one radio zone is transferred to a time slot in use in another zone that is geographically different. This occurs due to interference of radio waves from wireless channels.

In FIG. 10, a small zone covered by each wireless base station 30 is shown as a regular hexagon, and each wireless base station 30 is located at the center of the small zone.
is located. In this example, each of the radio base stations arranged at 1 to 7 uses a different radio channel, and the number of repetitions is 7.

In the present invention, since the radio channel given to the system is one channel, for example, if the same time slot is used for communication in adjacent radio channels, radio interference will occur and communication will become impossible. Therefore, in the present invention,
For example, the problem can be solved by adopting the following various methods.

i〉 Barrier exchange! ! 20, the time slots used by each radio base 830 are always known, and when a new call occurs, the gateway switch 20 instructs the radio bases to use time slots that do not cause radio interference. Station 3
0 and mobile radio 100.

) Even if the gateway exchange 1120 does not have the function described in i>, if the radio base station 30 or mobile radio device 100 is equipped with carrier sense for interference prevention,
If interference occurs, immediately replace the unused time
Give it the ability to move to a slot.

> Usable time slot numbers in each wireless zone are determined in advance, and the usable time slots of the wireless base station 30 that manage that wireless zone are selected from among the time slot numbers given in advance. let

Below, iii) will be explained in more detail.

FIG. 11 shows an example in which time slots of seven zones surrounded by bold lines are repeatedly assigned to each zone. The figure shows a case where each zone is given three time slots within one frame. The same wireless channel may be used in each of these zones. It goes without saying that the transmission timing of each time slot must be synchronized in all radio base stations 30.

However, it is assumed that the receiver of each wireless base station 30 can receive a signal in any time slot of any wireless channel. The time slot assignment is made by the radio base 83.
The signal to be transmitted is transmitted from 0, and there is no problem with radio interference during reception.

Now, as shown in Figure 11, the available time for each zone
When slot numbers are assigned, it can be seen that wireless zones that use the same time slot number are used in adjacent zones one after another. Then, sufficient attenuation for radio wave propagation is 19
Therefore, radio interference will not occur between zones that use the same time slot number.

Strictly speaking, there is a 1:1 correspondence between the known number of repetition zones and the time slot allocation method according to the present invention, that is, the number of repetition zones (the number of regular hexagons in the thick line in FIG. 11) is 7. In this case, it is not necessarily necessary that the time slot allocation should be divided into seven parts. This is because it depends on system design conditions. However, approximately, it can be considered that they correspond.

(1v) Method for removing pulse noise when receiving signals As already explained, the output signal when receiving the time division signal according to the present invention and multiplying the frequency (phase) discriminator output by 1q is as follows:
Although it is expressed by equation (5'), this is only an ideal case, and in practice, noise will occur due to various causes as explained below. These occur at the boundaries of each slot shown in FIG. 2A, and include a) those caused by discontinuity of different signals, and b) the rounding of the signal waveform due to the band characteristics of the intermediate frequency amplifier 143. Things related to both transmission and reception include C) a difference between the timing of the signal speed conversion circuit group and the timing at the time of reception (including delay time when the signal is transmitted through space);

The radio reception circuit 135
A method for removing the inside will be explained in detail using FIG. 1B-2. FIG. 1B-2 shows the mPA configuration of the radio reception circuit 135, in which the signal received from the antenna section is input to the reception mixer 136, and its output is sent to the intermediate frequency amplifier 1.
43 to amplify it to an appropriate level.

This output -815 is input to the clock recovery band 141 to recover the clock, and a portion of this is applied to the timing generator 142. Further, another part of the output of the intermediate frequency amplifier 143 passes through a gate circuit 144, and then is applied to a frequency (phase) discriminator 145, where the signal is demodulated. This gate circuit 144 is connected to a timing generator 142
The signals from the mobile radio l1100
In addition to No. 3 discriminator 145, unnecessary signals, such as signals sent to other mobile radio devices, are blocked. As a result, generation of distortion noise such as intermodulation is eliminated.

Now, the output of the discriminator 145 is again applied to the circuit 146 to goo1. This gate circuit 146 is for removing noise in the baseband band, and is mainly aimed at removing a) and C) of the noise in the front band.

Due to the action of this gate circuit 146, the speed restoration circuit 138
A good signal with significantly reduced noise will be added to the signal. Note that due to the action of this gate circuit 146, there is a possibility that a part of the desired signal may be blocked. To avoid this, move the signal mounting part in each slot shown in Figure 2A to the center of the slot, set a guard time at both ends of the slot, and avoid mounting the signal during this time. Bye. To achieve this, the signal rate conversion described above should be made a little faster, and when restoring the original signal after reception, the original signal should be restored at a correspondingly higher speed.

<V> Influence of Delay Time of Transmission Signal There are many factors that cause a large transmission delay at the transmitting/receiving end (transmitting/receiving terminal).

l> Divide the transmission baseband signal into regular intervals and store them in a storage circuit (for example, BBD, C0D).

ii> The signal received at the receiving end (receiving terminal) is divided into slots and stored in a memory circuit.

ii〉 Signal transmission time V due to the distance between the transmitter and the receiver Since the delay time is small, it is omitted.

Of the above, 1ii) is, for example, in the aforementioned car phone, the distance between transmitting and receiving is approximately 10 touch at most (wired section is omitted).
Because there is 10/300000KIn/see = 1/30
m5ecAlso, for mobile phones, a system has been proposed in which the communication area of one wireless base station is divided into extremely small zones with a radius of approximately 25 meters.Ito: ``Proposal of a mobile phone system - An approach to ultimate communication.'' ``IEICE Technical Report C8 Study Group November 1986 C386-88 and ``Mobile Telephone System Mochiyori 62-64023''.

In the above mobile phone system, the distance between transmitting and receiving is approximately 100 m at most (wired section omitted), so 100Trt/300000/see = 1/3
000 m5ec. Therefore i), ii
) is negligible compared to

Now, the occurrence of the delay times i) and ii) is schematically shown in FIGS. 12A and 12B.

In FIG. 12A, the input to the signal rate conversion circuit 51-1 in the station rate conversion circuit group 51 of the wireless base 430 is applied as shown in <a>, and (time flows from left to right) The trailing edge of the compressed signal A shown in (b) is obtained by compressing the lower signal A, which is the unit of speed (pitch) conversion, to T/n by the signal speed conversion circuit 51-1. The wireless transmitter circuit 32 outputs the same signal as shown in (C).
is output from. In the mobile radio device 100 that received this,
The speed restoration circuit 138 receives the compressed signal A at the timing shown in (d>) at the input of the speed restoration circuit 138, restores the signal A shown in (a), and outputs it as shown in (e). )
The delay time τ1 from the leading edge of the signal A to the leading edge of the signal A in (e) is T−T/n. However, the transmission time from the transmitter output section to the space transmission section and the reception section output of the mobile radio [100] was ignored.

In FIG. 12B, the signal speed conversion circuit 5 of the radio base station 30
In the input signal A shown in (a) to 1-1, the leading edge of the output signal A compressed to T/n is output at the same time as the trailing edge ends. Therefore, the output of the radio transmitting circuit 32 becomes as shown in (C), and the mobile radio receiving the output]0
The input of the speed restoration circuit 138 of 0 is as shown in (d>), and at the same time the trailing edge of the compressed signal is the same as the leading edge of the signal shown in (e) that has been time-expanded by n times and restored. Therefore, from what is shown in (e), T+T
2 occurs at a delay time delayed by /n-τ2.

Although the circuit for processing the signal shown in FIG. 12A is more complex than that shown in FIG. 12B, the delay time can be reduced. On the other hand, in the case of FIG. 128, the delay time is slightly longer, but the circuit is simpler.

Now, in actual communication, especially in two-way communication such as voice communication, the sender expects a response from the other party, so it is essential to set the delay time to twice τ1 or τ2. Try applying actual numbers. For example, if one time slot (one division) of the transmission signal is T = 1/10 seconds and the time compression coefficient n = 10, then 2τ1 = 2xl/10 (1-'1/10) = 18/
100-0.18 seconds (180ms) 2τ2=2X1/10 (1+1/10)=22/10
0=0.22 seconds (220 msec). On the other hand, the delay time in satellite communication is approximately 250m.
Since it is in seconds, the above value is about the same as in the case of satellite communication. If it is desired to reduce the delay time, it is sufficient to reduce the time slot (one time interval) in the baseband.

That is, by decreasing the lower than the above example, T=1/100
seconds, time compression coefficient n='l○O1, then 2τ1 =
2x1/100) (11/100) = 2x99/100
00〒0.02 seconds (20 m seconds) 2τ2 = 2x1/100) (1+1/100) = 20
2/10000 = 0.02 seconds (20 msec) As a concrete system, for example, the number of time slots allocated to the same mobile terminal within one frame is 10, and the time slots for other communications are cyclically allocated. It becomes possible to satisfy the above condition by setting the time of one frame to ]/10.

The above is the amount of delay time that is inevitably determined by system design, and the delay time for wired systems has been omitted. However, the delay time of the wired system can be compensated for, so it does not have a large effect on the system.

The delay time that may affect the system will be explained below. This is because the distance between the mobile radio device 100 and the radio base station 30 varies depending on the location of each mobile radio device.
When communication signals transmitted (received) from each mobile radio device are received by the radio base station 30, there is a possibility that gaps may occur due to differences in spatial transmission distances. .

For example, in the case of a car phone, a mobile radio device 100 is located near the radio base station 30, and another mobile radio device is located near the radio base station 30.
If you are at a distance of 10 meters from 0, the delay time difference is <1/30 m5ec as described above. That is, since the time slot may double by about Q, 03 m5 ec, it is necessary to provide a protection time of about 0.05 m5 ec.

In the case of a mobile phone, in the above example, the distance wi difference between the two mobile radios and the wireless base station 30 is 100 m, so the delay time difference is 0. It becomes OO03msec.

Therefore, in this case, it can be ignored in a system having signal components of 1M ports or less.

Next, a description will be given of the delay when iv) diversity transmission and reception is applied and the same signal is transmitted and received at the same time. The delay time caused by applying diaperity is
Mainly the control a signal is received.

In order to obtain a diversity effect, for example, when mixing control signals sent using two time slots with different time slot numbers, the signal in the younger time slot of -i is temporarily This is because the signal must be stored in the buffer 7--memory circuit, etc., and must wait for the signal sent later. From this point of view, if the occurrence of a large delay time is undesirable in the system, it is sufficient to send signals in adjacent time slots where there is not much difference in the time slot signals.

Next, for audio signals, there is no need to pay attention to the above points. Since the signal that was being sent is received and passes through the speed recovery circuit 138, the problem of signal delay is that the delay time only occurs in the lower numbered time slots, and the audio signal in the later time slots is delayed. teeth,
This is because the telephone call 8 from that time is speed-converted and transmitted, so there is no delay. Also, the timing of the start of the call signal is determined by the timing of the control signal when making and receiving calls, so even if the last number is given as the time slot number, that time will be the timing to start transmitting the voice signal. , speed conversion will be performed. Therefore, there is no difference in delay time depending on the time slot used.

(vl> Calculation of frequency effective utilization rate Calculate the frequency effective utilization rate as a system when using the pulse communication according to the present invention explained above and when using conventional FM communication. The modulation signal is voice, and the communication Assume a circuit.The following values are taken as the formula crystal element.

1) Pulse communication of the present invention 1 radio channel with 10 time slots or audio 1
0 channel can be transmitted. The required frequency bandwidth is 3K) - 1z xl 0 = 30KHz By providing a protection band, ±
40 and set to 1z. This value is somewhat disadvantageous to the present invention, and in reality, such a wide guard band is unnecessary, but this value is used for comparison.

2) In the case of conventional FM communication (one channel of audio/wave transmission), the baseband signal of one wireless channel τ is one channel of audio, so the required frequency bandwidth is 3KHz x
1 = 3KHz As a protective band, a mouth 2 is required at ±8, and the transmission interval between two glands is 12゜5KHz as shown in Fig. 13(b).
<250Mt-1z /400M1-1 in Japan
This standard is widely used in 2-band code 1-nos telephones and the like. > Therefore, in order to simultaneously transmit 10 channels of audio signals, 1 2, 5KHz xl 0 = 125K
It turns out that Hz is required.

Comparing the above two systems, the ratio between the present invention and the conventional example is 80:125-0.64. In other words, in the pulse communication according to the present invention, SCPC (Si
channel per carrier)
It can be seen that a frequency band of only about 60% is sufficient compared to .

As the number of channels (number of simultaneous callers) increases, for example, when comparing 100 voice channels, the required frequency bandwidth for the pulse communication of the present invention is (3 days ZX100 + 50 (guard band > KH2) X2 = 700KHz In conventional FM communication (SCPC), 1 2, 5KH2xl 00-1 250KHz
Comparing the two systems, the ratio is 700:1250=0.56, which further increases the superiority of the present invention.

Next, let's look at TDMA (
Time Divisin Haltiple Acc
A comparison will be made between the frequency effective utilization rate when the ESS) is applied to mobile communication and the present invention.

3) For the DMS90 system (References: F,
Lindell et al.”Digital Ce1lular
Radio for the1990S”Telec
communications P, 254-2650c
t1987) In this system, 10 audio channels (1 channel is 16 bits/second) can be multiplexed at a transmission rate of 340 bits/second, but the carrier interval (required frequency bandwidth) is 300 KPIZ. ing.

Therefore, the frequency utilization ratio of the present invention in 1> and the DMS 90 in 3> is 80:300=0.267. That is, the superiority of the present invention is more remarkable than that of the analog system (SCPC).

(8) Non-telephone systems other than call signals (Hiro: i5 area Shinkyu)
Application of the present invention to communications using It is also applicable to communications using telephone signals, especially broadband signals.

Alternatively, voice and these non-telephone signals can be transmitted using the same wireless channel. This will be explained below.

As shown in FIG. 3B, the signals contained in each time slot shown in FIG. 2A all have approximately the same maximum frequency, which in this case is about 45 KHz. Keeping this in mind, for example, the baseband signal, i.e. the first
If the highest frequency of the input signal to the signal speed conversion circuit group 51 shown in FIG. The highest frequency is almost equal to the audio signal,
Negative effects on radio interference will be avoided. It turns out that in order to do this, the speed of signal speed conversion should be reduced to 1/2 that of voice. Similarly, if the highest frequency included in the image value @ Tohoku: F\1 range signal is 10 times that of the audio signal, the signal speed is converted to 1/10, and 10 time slots are allocated. All you have to do is give it your share.

Next, in order to obtain smooth system operation, it is not wise to transmit signals with extremely different bow speeds on the same radio channel, and it is not advisable to transmit signals with extremely different bow speeds on the same radio channel.

High-speed data (30K Hz > , wide range)
300 and 300, and allocate separate wireless channels. However, in the event of congestion in communication traffic, regardless of the above, if a system rate configuration that allows for the mixing of different types of signals is adopted, a system with a high frequency utilization rate and resistant to traffic fluctuations can be created. 4f4 will be built.

(9> Application of the present invention to a system that uses the same radio frequency for transmission and reception of a radio base station and a mobile radio device) As a channel, wireless base station 3
This is a case where the transmission frequency from 0 and the transmission frequency from mobile radio device 100 are different from each other. However, the present invention is not limited to these.
The present invention is also applicable to a system in which the wireless base station 30 and the wireless base station 100 use the same radio frequency (a so-called ping-pong transmission system), which will be described below.

In this case, it is necessary for the radio base station 30 and the mobile radio device 100 to receive radio signals from opposing radio devices without radio interference. This will be satisfied if different times are given sequentially. The mobile radio 1jI11100 used here includes not only the one shown in Fig. 1B-1 but also the mobile radio a shown in Fig. 1D.
lo.

B can also be used. In order to explain specifically, the 21st
Use Figures or Figure 2N.

FIG. 21 is a diagram corresponding to the above-mentioned FIG. 2A, and the output of the wireless transmitting circuit 32 of the wireless base station 30 and the input of the wireless receiving circuit 35 are shown in FIG. 21(a) and <b>, respectively. There is. In the figure, time slots SD1 to SDn for transmission signals from the radio base station 30 are lined up in the first half frame of one frame, and no transmission signal is output in the second half frame. , conversely, it can be seen that these 1/2 frames are used as time slots SU1 to SUn when the mobile radio device 100 transmits. That is, in the wireless base station 30, a plurality of mobile wireless devices 1
The transmitted signals within each time slot 5u-sun from 00 are received in chronological order, and this 1/2
Since there is no transmission from the wireless base M2O within the frame, the signal can be received satisfactorily without wireless interference.

Figures 2J and 2D are the aforementioned Figures 2C and 2D.
This is an example in which transmitting and receiving durversity is performed in figures corresponding to the figures shown in FIG.

It is clear from the explanation given in FIG. 2F that this system works well with the timing of the time slots shown in FIGS. 2J and 2.
2 and 2N show an example of the time slot arrangement when the same radio frequency is used for other transmissions and receptions.

FIG. 2L shows that after one downlink time slot 5D1 (FIG. 2(a)) is output from the wireless transmission circuit 32 of the wireless base station 30, an uplink time slot 5U1 (FIG. 2(b)) is output from the mobile radio 1100. ) fi [received by the line receiving circuit 35,
In the same manner, it is shown that the operation of transmitting SD2 and receiving 5tJ2 continues.

Figure 2M shows two downstream time slots 5D1°SD2
((a) in the same figure) and transmits the uplink time slot SU
1. It shows that the operation of receiving SU2 continues.

Figures 2N (a) and (b) show the downlink time of rllllMI.
Slot SDI~5Drl is transmitted, and n uplink time slots SUI~ with different time slot lengths are transmitted.
It shows that the operation of receiving Sun continues.

In the case of the same figure, the downstream time slot length is the same as the upstream time slot length.
This time slot arrangement is such that the mobile radio device 100 (terminal side) makes a short response in response to a command from the wireless base station 30 (land side). This would be convenient when transmitting data.Also, if the amount of data transmitted by the mobile radio Fjlloo (Ga terminal side) is larger than that by the land line side, of course,
The time slot length of the uplink time slots SU1 to Sun is longer than that of the downlink time slots 5D1 to 5D3 [)n.

Next, if you perform ping-pong transmission as described here,
The fact that the configuration of the transmitting/receiving device is simplified will be explained with reference to FIG. 1D (of course, it can also operate with the configuration shown in FIG. 1B-1).

FIG. 1D corresponds to FIG. 1B-1, and the operations of the mobile radio device 100B are as shown in FIG. 1B-1 except that the transmission and reception frequencies are the same and the transmission and reception timings are different.
The transfer heat 'lI! explained in Figure 1! There is no difference in the operation of Aircraft A 100.

That is, in FIG. 1D, local oscillator 1 of FIG. 1B-1
21-2, the local oscillator 12"l-1 is shared, and the switch 122 of the transmission/reception intermittent controller 123B
For example, if the output timing to 122-1 and the output timing to 122-2 are as shown in FIG.
Other than the difference of /2 frames, there is no change in the operation of the mobile radio device 100. Similarly, the configuration of the wireless base station 30 can be simplified following the mobile wireless device 100B.

Next, in order to apply the system operation explained in sections (1) to 8) to the water ring, the following changes should be made.

〉 Downlink Frequency 1. Set both upstream frequencies fl to Fl ii) The time required to transmit a signal within one frame doubles, so if there is a problem with the communication system in terms of signal delay time, The length of one time slot is 1/
Shorten to 2. In other words, (double the speed at which the original signal is time-compressed as explained in sections 1 to 8), or double the division speed when time-dividing the original signal. When receiving, do the opposite. As explained in this chapter, when the present invention is applied to mobile communications that perform Bing Bong transmission, the following advantages arise.

〉 Possible to simplify the hardware configuration.

〉 When Bing Bong transmission was implemented using the conventional digital method, the pulse waveform was distorted due to the multiplex propagation characteristics of radio waves, and the average bit error rate deteriorated significantly.

Moreover, this is a high-speed signal transmission, for example, a signal speed of 20
When it exceeded 0 KpbS, the effect was significant. On the other hand, since the method according to the present invention is essentially analog transmission, although it is affected by multiple propagation, the degree of influence is slight. In particular, when analog audio is transmitted by spatial transmission, even if the multiplicity is 100, the highest frequency of the audio signal is as low as 3KHz x 100 = 300. Compared to actual examples in which transmission ranges from 2 to 12 MH2, this is sufficiently moderate, so there is no particular problem.

(10) Advantages of the system to which the present invention is applied in terms of frequency utilization The frequency utilization efficiency of the system using the time-division time compression "M modulation method" of the present invention will be explained by comparing it with various types of mobile communications currently in use. It will be clarified that the present invention is superior in terms of utilization efficiency compared to others.When looking at the system operations explained up to section (9) in terms of frequency utilization efficiency, the system that exhibits the most power is the one that utilizes the given frequency bandwidth. This is a case where the degree of compression is increased until it is fully used, and the system is operated with only one U-role transmitter for both uplink and downlink.

A few practical examples will be described below, such as a case where the present invention is applied to a mobile telephone system using the frequency band used by a cordless telephone.

(i) If the present invention is applied to all frequency bands of cordless telephones, the frequency bandwidth used by cordless telephones in Japan will be 12.5KH2x89C for both upstream and downstream! =1112.5KHz /
It is 89CH. Now, if this band is all used in one carrier wave as in the system according to the present invention, what is the maximum value of the number of time slots in one frame? The signal bandwidth of one telephone channel is 3.0-0.3 = 2.7, or 2.7Ktl
z, and frame efficiency (effective information in one frame tfF
The amount i expressed by the number of time slots is the total time
If the value divided by the slot) is 0.9, the maximum number of time slots in one frame is 1112, 5(K)iz) ÷ 2 (frequency band on one side) ÷
2.7 (KHz) x O,9 = 185.4 That is, it can be seen that if it is a voice (telephone) signal, 185 calls can be transmitted simultaneously. This is a value assuming that the depth of AM or FM modulation is extremely shallow; in reality, there is a spread of sidebands due to modulation, and 1 may be estimated to be about 20% lower in order to stay within the specified frequency band. is necessary. Therefore, 1BS, 4x O,8 = 148.3
(CH) In other words, 148 calls can be transmitted simultaneously.
:7ru.

It can be seen that this is an effective frequency utilization rate nearly 1.6 times that of current cordless telephones.

(ii> Frequency utilization efficiency when the present invention is applied to a car telephone system) Let us consider a case where the present invention is applied to a car phone system (NTT's large capacity system) applied in Japan.

Since the frequency bandwidth is 15 MHz (each upstream and downstream), if we calculate it in the same way as in (i), we get (15 (MHz) ÷ 2
)÷2.7(KHz) x 0.9x 0.8=200
0, 2000 time slots are available within one frame. That is, 5CPCtl = 2000 channels. On the other hand, in the current system, there are 1200 channels and 1200 channels interleaved, so
Although not all channels can be used in the same area, it is estimated that 1800 channels can be used at 50%. Even in this case, the frequency utilization efficiency of the present invention is superior.

In addition, in the US AMP system, 666 channels are used with 30 days Z interleaving, and the frequency bandwidth is 2.
It is 0MH2. If this bandwidth is used in the method of the present invention, 2666 channels can be used. It should be noted that the AMP method is being considered to be improved to a system with about 2000 channels per 1q, but the present invention is more effective in this case as well. Furthermore, DM is being considered in Europe.
Compare with S90 system.

This system allows multiplex transmission of 10 audio channels (1 channel is 16 bits/second) at a transmission rate of 340 bits/second, but the carrier spacing (required frequency bandwidth) is 300 bits/second. Since the frequency bandwidth used in the DMS90 system is unknown, it is not possible to make an accurate comparison, but it is assumed that the bandwidth is the same as that of the AMP system, and that
Although it is expected that phase modulation and the like will be introduced, the superiority of the present invention will not change.

In the method described above, since there is only one carrier wave frequency, it is sufficient to simply use the local oscillator 120 as shown in FIGS. 1B-1 and 1D, and there is no need to use a synthesizer, so the circuit Configuration becomes easier.

In addition, in the system of the present invention, if the degree of signal compression is increased, the effect of multiple wave propagation v1, which is a problem in high-speed digital mobile communication, becomes easier to suffer. Even in this case, it is better to make the degree of compression as high as possible, but there is a limit due to the above-mentioned influence, and a plurality of carrier waves will be used as a system. 'Tj, the frequency utilization efficiency will decrease, but even in this case, the present invention is advantageous because it has a 20% to 40% higher effective utilization efficiency than the digital systems currently in use or currently under development.

[Effects of the Invention] As is clear from the above description, by applying the present invention to a mobile communication system, it is possible to construct a system with higher frequency utilization efficiency than conventional systems. In addition, in order to increase the effective use of normal frequencies, other design parameters such as adjacent channel interference, co-channel interference, and delay characteristics of transmission signals that affect line quality can be designed to values that can be effectively ignored. be.

In general, by applying the present invention to a mobile communication system that uses a small zone configuration, a temporary interruption in communication occurs when a zone is changed during communication, as in conventional systems, and in the case of a communication center, Although this is not a problem, facsimile signals and data signals are completely removed because they cause problems due to image quality deterioration and burst-like transmission errors. In addition, in a system to which the present invention is applied, since the wireless channel is unique, there is no need for a carrier sense function or a frequency synthesizer that is essential for a system with multiple wireless channels, making it possible to achieve economicalization. . This makes it possible to carry out various types of transmitting and receiving diversity between the same wireless base station or multiple wireless base stations without causing interference, which will greatly contribute to improving communication volume. The effects of the present invention are extremely large.

[Brief explanation of drawings]

FIG. 1A is a block diagram showing the configuration of the barrier switch included in the system of the present invention and its connection relationship with the telephone network and radio base station. FIG. 1B-1 is a circuit diagram of a mobile radio used in the system of the present invention. 1B-2 is a detailed circuit diagram of the radio receiving circuit shown in FIG. 1B-1; FIG. 1C is a circuit diagram of the radio base station used in the system of the present invention; FIG. 2A is a circuit configuration diagram showing another embodiment of a mobile radio device used in the system of the invention; FIG. 2B is a time slot structure diagram for explaining the time slots used in the system of the invention; 2C and 2D are diagrams showing the time slot structure for explaining channel switching in the system of the present invention. Spectrum diagrams and circuit configuration diagrams for explaining configuration examples of control signals used in the invention, Fig. 2F, Fig. 2G, Fig. 211, Fig. 21, Fig. 2J, Fig. 2, Fig. 2L, Fig. 2M and 2N are block diagrams for time slot 1 to explain other time slots used in the system of the present invention, and FIGS. 3A and 3B show the spectrum of telephone calls and control signals. 4A and 4B are flowcharts showing the flow of the location registration operation of the system according to the present invention, and FIGS. 5A, 5B and 5C are flowcharts showing the flow of the calling operation of the present system, 6th
Figure A, Figure 6B, Figure 6C, and Figure 6D are flowcharts showing the flow of the call receiving operation of this system, Figures 7A, 7B, Figure 7C, and Figure 7D are time slot switching of this system. Flowchart showing the flow of operation. FIG. 8A, FIG. 8B, FIG. 8C and FIG. 8D are flowcharts showing the flow of operation when transmitting and receiving diversity is implemented by this system. FIG. 9 is a flowchart showing the flow of operation when transmitting and receiving diversity is implemented by this system. 10 is a configuration diagram showing a small zone configuration to which the present invention is applied; FIG. 11 is a configuration diagram showing a small zone configuration to which the time slot allocation of the present invention is applied. Figures 12A and 12B are timing charts for explaining the delay time that occurs during signal compression and expansion in this system, and Figure 13 is for explaining the required bandwidth of this system and the conventional system. FIG. 14 is a conceptual configuration diagram for explaining the conventional system. 10... Telephone network 11... Gateway switch 20
...Gateway switch 21...Communication control unit 22-1
~22-m...Communication signal 23...Switch group 24...ID identification storage section 25...S/N monitoring section 30...Radio base station 31
...Control/call signal processing unit 32...Wireless transmission circuit 35...Wireless reception circuit 3
8... Signal speed restoration circuit group 38-1 to 38-n... Transmission speed restoration circuit 39...
Signal selection circuit group 39-1 to 3-n...Signal selection circuit 40...1
] Control section 41... Clock generator 42... Timing generation circuit 51... Signal speed conversion circuit group 51-1 to 51-n... Signal speed conversion circuit 52...
Signal assignment circuit group 52-1 to 52-n...Signal assignment circuit 81...Speech path control unit 82...ID identification memory 81S83...
Switch group 91...Digital encoding circuit 92...Multiple conversion circuit '100...1 line machine before movement 101...Telephone section 120...Reference crystal oscillator 121-1, 121-2... Local oscillator 122i, 1
22-2...Switch 123...Transmission/reception intermittent controller 131...Speed conversion circuit 2...Wireless transmission circuit 133...Transmission mixer 4...
- Transmitter 135...Radio reception circuit 6...Receiver 137...Receiver 8...Speed restoration circuit 139...Signal division circuit 1...Clock generator 2...Timing generation Device 7...Speech quality monitoring section 2...ID information verification storage section.

Claims (1)

[Scope of Claims] Each radio base means (30) each covers a plurality of zones and constitutes a service area, and a frame for moving across the plurality of zones and communicating with the radio base means. barrier exchange means (20 ), and using at least one of said time slots in which said radio base means and said mobile radio means are substantially synchronized.