JPH0453321A - Method and system for transmitting time division communication signal - Google Patents

Abstract

PURPOSE:To improve the transmission quality and the economy by devising this system such that the signal speed of a communication signal is quickened, the signal is multiplexed to obtain a multiple load gain on a transmission line between a gate exchange and lots of exchanges. CONSTITUTION:A general telephone network 10 is connected to a gate exchange 20, for which lots of exchanges (19-1)-(19-Z) are connected and each of radio base stations (30-1)-(30-i), (30-j)-(30-m), (30-w)-(30-Z) is connected to each of the exchanges (19-1)-(19-Z) respectively to form a hierarchy structure. In the transmission between the gate exchange 20 and lots of the exchanges or between the exchanges, a multiple load gain is obtained by quickening and multiplexing the signal accommodated in a time slot blocked and converted into a high speed. Thus, the transmission quantity is improved and the economy is attained.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to communication in fixed or mobile communication of a plurality of exchanges connected to one barrier exchange or telephones and mobile radios housed in the exchange. Concerning channel time division communication method and system. More specifically, a certain radio channel is given, and this is used to set up a radio link with one or the opposite radio base station of a large number of mobile radios in the service area, and connect the gateway switch or multiple exchanges. The present invention relates to a method and system for transmitting time division multiplexed telephone signals flowing through a wired transmission line when communicating with other mobile radios or telephones in the system via a wired transmission line.

[Prior Art] In mobile communication using voice to which a small zone system is applied, a system that employs hour-minute pJ-time compressed multiplex signals is described in the following document.

Literature 1. Ito “Study of mobile phone system - Time division time compression F
Proposal of M modulation system - PA IEICE technical report RC389-11 July 1989 document 2. Study of ItoP mobile phone system - Time division time compression F
Theoretical study of M modulation system” IEICE technical report RC389-39
October 1989 document 3. Ito "Elucidation of the multiple load gain of time division time compression multiplexed telephone signals and its application to FM mobile communications" IEICE technical report RC38'1165, that is, in document 1,
The transmitted signal (baseband signal) is divided into predetermined time intervals and stored in a storage circuit, and when read out, it is read out at a predetermined time slot at a speed n times faster than the speed at which it is stored in the storage circuit, and this time・Receivers that communicate with each other and are built into mobile radios and radio base stations in order to angle-modulate or amplitude-modulate carrier waves with the signals accommodated by the throwers 1 and 2 and transmit and receive them intermittently over time. A switch circuit is provided for a wireless receiving circuit having a mixer, a wireless transmitting circuit having a transmitting mixer, a synthesizer applying voltage to the receiving mixer of the wireless receiving circuit, and a synthesizer applying voltage to the transmitting mixer of the wireless transmitting circuit. A method is used in which the 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 mobile radio device for the radio base station communicating with the opposing side. In order to extract only the signal accommodated in the time slot, the radio receiving circuit opens and closes to receive the signal, demodulates the signal, stores it in a storage circuit, and when reading it out, the speed at which it is stored in this storage circuit. An example of a system has been reported in which a system is constructed in which it is possible to reproduce the baseband signal, which is the original signal that has been transmitted, by reading at a speed that is one nth of the original signal.

Next, in Document 2, studies are conducted on adjacent channel interference and co-channel interference, which are problems when applying the TCM (time division time compression multiplexing)-FM method described above to small zones.・The possibility of realizing the system has been shown by appropriately selecting parameters.

Furthermore, in Reference 3, among the TCM signals mentioned above, conventional FDM (frequency division multiplexing) is used for signals in which audio is multiplexed.
It has been proven that the signal has a multiload gain similar to the known multiload gain, and the value of the above multiload gain is determined under the given system design parameters.
The advantages when applied to FM mobile radio are explained.

However, in the above-mentioned documents 1 and 2, the TCM method is mainly explained only as an example applied to a wireless system between a wireless base station and a mobile radio device, and barrier exchanges or exchanges are usually used not only for wireless systems but also for wired systems. By applying the TCM method to these devices, it is possible to communicate between wired telephones, mobile radios, or between arbitrary terminals such as between telephones and mobile radios. No example is given. In addition, although Document 3 describes the multiple load gain of TCM signals, this is mainly for wireless systems, and when applied to wired signal transmission such as communication between exchanges, for example. is not shown either.

[Problems to be Solved by the Invention] In the system construction examples shown in Documents 1 and 2 above, T
This was a case in which the CM signal was applied to a radio system between a radio base station and a mobile radio, and used in the form of CM-FM. If there are wired telephones, etc. in the same system and the wireless and wired systems are used together, using TCM only for the wireless system not only poses problems from the point of view of system harmony, but also
The multi-load gain of the CM telephone signal was not utilized, and there was no technology to utilize it, resulting in a large loss from the economic point of view of the system.

Furthermore, as the scale of the system increases, the network structure becomes layered and switchboards are installed, and the networks are connected by transmission lines.

In this inter-switched line transmission, as the scale of the system increases, the transmission distance increases, and it becomes necessary to insert an amplifier or the like along the way. In this case, if the multiple load gain is clearly known, it can be incorporated into the amplifier design, making it possible to improve transmission quality and make it more economical. In addition, as the system becomes large-scale, communication between switched lines becomes essential, and the signals flowing through the transmission path are densely multiplexed TCM.
It becomes a signal. In such massively multiplexed transmission, whether or not the value of the multiple load gain is known has a great impact on line design, transmission quality, and even system economics. There was a problem that needed to be solved: the value was not clear, nor was the means to use it effectively.

[Means for solving the problem] In a mobile radio device, a transmission signal (baseband signal) is divided into predetermined time interval units and stored in a memory circuit, and when read out, n is faster than the speed at which it is stored in the memory circuit. Built-in mobile radio equipment for reading out data at a predetermined time slot at double high speed, angle-modulating or amplitude-modulating the carrier wave with the signal accommodated by this time slot, and transmitting and receiving the signal intermittently in time. , a switch for a radio receiving circuit having a receiving mixer that communicates with each other, a radio transmitting circuit having a transmitting mixer, a synthesizer applying voltage to the receiving mixer of the wireless receiving circuit, and a synthesizer applying voltage to the transmitting mixer of the wireless transmitting circuit. A circuit is provided to intermittent the output of each applied synthesizer, and to synchronize this intermittent state for both transmission and reception, and also to synchronize the radio base station that communicates with the mobile radio in order to transmit and receive signals using time slots. Using the method, on the mobile radio device side, in order to extract only the signal accommodated in the predetermined time slot, the radio reception circuit is opened and closed to receive the signal, and the signal obtained by demodulation is stored in the storage circuit, When reading this, n is the speed at which it is stored in this memory circuit.
By reading at a speed that is one-fold slower, it is possible to reproduce the baseband signal, which is the original signal that was transmitted.

As a result, even if there are a large number of wireless base stations in this communication system, the signals of many channels are all processed in the form that is accommodated in the time slots assigned to each, and the signals of voice, data, images, etc. Since there is no need to recognize the type of individual signals even for composite signals, signal transparency increases compared to conventional systems, enabling efficient system operation and economical system construction. became.

A wired telephone is equipped with a mobile radio without the radio functions. In addition, a signal speed converter is installed in the exchange and the barrier exchange, and when a TCM telephone signal is input/output from one exchange to another exchange or a barrier exchange, this communication system is used to transmit the signal with a high degree of time compression. The system was built.

[Function] Input signals from the telephone network external to this communication system are separated by a signal speed conversion circuit included in the gateway exchange, converted to high speed, and sent to the wireless system.
The system transmits and processes signals accommodated in time slots that are separated and converted to high speed, and when sending signals from this communication system to an external telephone network, the signals are separated and converted to high speed. The signal accommodated in the time slot is separated by a signal speed restoration circuit included in the barrier switch and restored to a series of signals before being converted to high speed.

Within this communication system, signals that are separated, converted to high speed, and accommodated in time slots are exchanged and processed, and transmission between a barrier switch and many switches, or between switches is By further increasing the speed of the signals accommodated in the time and slots converted to high speed and multiplexing them, multiple load gain is obtained.

As a result, even if the scale of the system increases and the transmission path between the barrier exchanges and the exchanges becomes longer, this multiple load gain can be used effectively to avoid complicating the system and increasing costs. We were able to create a highly reliable system without any problems.

[Example] Figures 1A-1, 1A-2, and 1A-3.

FIG. 1B, FIG. 1C-1, FIG. 1C-2, and FIG. 1D show a system configuration for explaining an embodiment of the present invention.

Figure 1A-1 shows the overall system configuration, with 10
is a general telephone network and is connected to the barrier switch 20. The barrier switch 20 has many switches 19-1 to 19.
-7 is connected, and each of the exchanges 19-1 to 19-7 has wireless base stations 30-1 to 30-i, 30-j.
30-m and 30W to 30-Z are connected to form a hierarchical structure. Here, each wireless base station 30-1
~30-2 have wireless receiving circuits 35-1~35Z, respectively.
and radio transmitting circuits 32-1 to 32-7, and can transmit and receive data to and from many mobile radio devices.

FIG. 1A-2 shows the internal configuration of the barrier switch 20. The gateway switch 20 connects a wired telephone network 10 and a transmission line 2.
Telephones 200-1 to 200 connected by 1-1 to 21-p
An exchange 19 serving as an interface between 0-p and the wireless system is connected through exchange.

The barrier switch 20 includes a signal processing section 31. switch group SW,
Signal speed restoration circuit group 38-1 to aS-;

It includes signal speed conversion circuit groups 51-1 to 51-1 and a communication control section 45 for controlling them. Here, a wired telephone 200 and a telephone network 10
In addition to communicating with telephone terminals housed in the telephone terminal or wired or wireless telephone terminals within the system example forming the present invention, communications are performed with many exchanges 19 within the system via the signal speed converter 36. It is connected.

Further, each of the many exchanges 19 connected to the barrier exchange 20 has many wireless base stations 30-1, 30-2, .・・・
. , 30-Z through a transmission line, and transmits and receives signals converted at high speed and accommodated in a plurality of divided time slots.

Next, the internal configuration of the barrier switch 20 will be explained.

The signal processing section 31 includes the telephone network 10 and the signal speed restoration circuit group 38.
-1 to 3S-1, signal speed conversion circuit group 51-1 to 51-
1, and performs 2-wire to 4-wire signal conversion.

The switch group SW is connected to the exchange 19 via the signal speed converter 36, and is also connected to the telephones 200-1 to 200-p via transmission lines 211 to 21-p,
Exchange is performed in accordance with instructions from the control unit 40 to enable arbitrary combinations between the signal speed restoration circuit groups 381 to aa= and the signal speed conversion circuit groups 51-1 to 51-1.

The communication control section 45 includes the signal processing section 31. Signal speed restoration circuit group 38-1 to 3a-r, signal speed conversion circuit group 51-1 to 5
a clock generator 41.1-1 for supplying timing signals; It includes a timing generation circuit 42, a control section 40° for control, and an ID information storage circuit 43.

FIG. 1A-3 shows the internal configuration of the exchange 19 (for example, 19-1). The signal speed converter 46 serves as an interface with the barrier switch 20, and speeds up TCM telephone signals and transmits them to the barrier switch 20, while receiving high-speed TCM telephone signals from the barrier switch 20. Switch group SWb is transmission line 200b-1 to 200t)-Q
is connected to the telephones 200b-1 to 200b-Q,
The exchange is also connected to the radio base stations 30-1 to aO-t through a transmission path, and enables arbitrary combinations between the telephone 200b and the radio base station 30 and between the signal speed converter 46. This is performed according to instructions from the control unit 40b. The communication control section 45b includes a signal speed conversion section 46. It controls the switch SWb, and includes a clock generator 41b for supplying a timing signal, a timing generation circuit 42b, a control section 40b for control, an ID information storage circuit 43b, and a wireless channel information storage circuit 446). .

FIG. 1B shows a circuit configuration of a mobile radio device 100 that communicates with a radio base station 30.

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 sent to a speed recovery circuit 138, a control section 140, and a clock. The signal is input to the regenerator 141. The clock regenerator 141 regenerates a clock from the received signal and applies it to the speed recovery circuit 138, the control section 140, and the timing generator 142.

The speed recovery circuit 138 calculates the speed (pitch in the case of an analog signal) of the compressed and segmented communication signal in the received signal.
is restored and input as a continuous signal to telephone section 101 and control section 140.

The communication signal output from the telephone unit 101 is divided into predetermined time intervals by a speed conversion circuit 131, and the speed (pitch in the case of an analog signal) is made high (compressed) and sent to a transmission mixer 133. The signal is applied to the wireless transmission circuit 132 including the section 134.

The output of the modulator included in the transmitting section 134 is transmitted to the transmitting mixer 13
3, the signal is converted to a predetermined radio frequency, transmitted from the antenna section, and received by one radio base station 30. The received signal is transmitted to the exchange 19 where an available time slot is searched and the same radio base station 30
A permission to use the time slot is sent to the mobile radio 1fal 00. In order to send a radio signal to the radio base station 30 using a time slot that is permitted to be used, timing information from the timing generator 142 shown in FIG. 1B is obtained via the control unit 140. It is necessary.

In this timing generator 142, a clock regeneration type 14
1 and a control signal from the control section 140, the transmission/reception intermittent controller 123. It supplies necessary timing to the speed conversion circuit 131 and speed restoration circuit 138.

This mobile radio device 100 includes a synthesizer 121.
-1 and 121-2, and the changeover switch 122'-1,
122-2, a transmission/reception intermittent controller 123 and a timing generator 142 that generate signals for switching the changeover switches 1221 and 122-2, respectively.
Synthesizers 121 - 1 and 121 - 2 , transmission/reception intermittent controller 123 , and timing generator 142 are controlled by control section 140 . Each synthesizer 1211.12
1-2 is supplied with a reference frequency from a reference crystal oscillator 120.

The rate converted n between the wireless base station 30 and the exchange 19
The communication signal of the channel is connected to the radio transmitting circuit 32 or the radio receiving circuit 35 of the radio base station 30 via a transmission path. The signal sent from the exchange 19 is sent to the wireless transmission circuit 32
After being amplified to an appropriate level and amplitude or frequency modulated, it is converted to the required carrier frequency by a mixer circuit (not shown) included therein, and then directly or via a high frequency amplifier (not shown). Power is supplied to the antenna. On the other hand, the signal transmitted from the mobile radio device 100 is received by the radio receiving circuit 35. The input signal from the antenna section is converted to an appropriate intermediate frequency by a mixer circuit (not shown), then amplified and input to an amplitude detector or frequency discriminator (not shown). The high-speed segmented reception signals transmitted from the mobile radio device 100 are sent to the exchange 19.
sent to. The functions of each of the above circuits are as follows:
It is almost the same as the corresponding circuit.

As explained above, the wireless base station 30 to which the present invention is applied does not have any control function such as 01 port,
It has an easy-to-maintain configuration with only a so-called through repeater function. Therefore, when the mobile radio device 100 makes and receives calls, control is exchanged between the mobile radio device 100 and the exchange 19, and the radio base station 30 is not substantially involved at all.

FIG. 10-1 shows a detailed circuit configuration of the barrier exchange 20 portion. There is one exchange 19-1 here,
A signal speed increasing circuit group 36a1 and a signal speed slowing circuit group 36 included in the signal speed converter 36 in the barrier switch 20
b-1 is connected to the signal speed conversion circuit 5 via the switch group SW.
Signal speed conversion circuit group 5 including 1-1-1 to 5l-1-n
11 and a signal speed restoration circuit group 38-1 including signal speed restoration circuits 3811 to 38-1-n. The signal speed increasing circuit group 36a-1 includes many signal speed increasing circuits 36a-1-1 to 36a-1-n, and the signal speed decreasing circuit group 36b-1 includes many signal speed decreasing circuits 36a-1-1 to 36a-1-n. Circuits 36b-1-1 to 36b-1-n are included.

FIG. 10-2 shows a detailed circuit configuration of the exchange 19. Here, the radio receiving circuit 35-1 of one radio base station 30-1. Signal speed acceleration circuit group 4 included in signal speed converter 46 corresponding to wireless transmission circuit 32-1
6a-1, signal speed slowing circuit group 46b-1, and barrier switch 20. Only the relationships between the transmission lines 21-1 to 21-p are shown, and those related to the other radio base stations 30-2 to 30-i are omitted. The signal speed increasing circuit group 46a1 includes many signal speed increasing circuits 46a-1-1 to 46a-.
1-n, and the signal speed slowing circuit group 46b-1 includes many signal speed slowing circuits 46b-1-1 to 46b-1-.
Contains n.

The signal from the telephone network 10 is subjected to 2-wire to 4-wire conversion in the signal processing unit 31, and then sent to signal speed conversion circuits 51-11 to 5l-1-.
The signals are input to a signal speed conversion circuit group 51-1 including signal speed conversion circuit group 51-1, and undergo speed (pitch) conversion at predetermined time intervals. The function of the signal speed conversion circuit group 51-1 is to store input signals such as audio signals and control signals divided into fixed time lengths in a storage circuit, and change the speed when reading them out. By reading at twice the speed, it is possible to compress the time length of the signal. The principle of the signal speed conversion circuit group 51-1 is the same as when playing back audio recorded by a tape recorder at high speed, and in reality,
For example, CCD (Charoe Coupled De
vice ), BBD (Bucket Brig
adeDeViCe) can be used, and the memory used in television receivers and tape recorders that compress or expand the time axis of conversation can be used (References: Koita et al. ``Compressing the time axis of conversation /Stretching Tape]-da'' Nikkei Electronics 19
July 26, 1976, pp. 92-133).

COD and BBD illustrated in signal speed conversion circuit group 51-1
As described in the above-mentioned document, the circuit using the circuit can be used as it is for the signal speed restoration circuit group 381. In this case, the timing is determined by the clock from the clock generator 41 and the control signal from the control section 40. This can be achieved by making the reading speed slower than the writing speed in response to a timing signal from the timing generator 42 that generates the timing signal.

The high-speed signal for one section outputted from the signal speed conversion circuit group 51-1 via the switch group SW is sent to the signal speed conversion section 3.
In step 6, the signal speed is further increased and the signal is sent to the signal speed converter 46 of the exchange 19.

The state of the signal that has been compressed by the signal speed conversion circuit group 51-1 is shown in FIG. 2A and will be described.

The output signal of the signal speed conversion circuit group 51-1 is given time slots in a predetermined order. Second
SDl in Figure A (a), 5D2-.

In SDn, the speed-converted communication signal is
This indicates that the slots are allocated by slot.

Here, one time slot accommodates a synchronization signal and a speech signal or/and control signal as shown in the figure. If the call signal is not implemented, only the synchronization signal is added and the empty slot signal is added to the call signal portion.

In this way, as shown in FIG. 2A (a), the switch SW of the barrier switch 20 has the time slot SD1.
A signal forming one frame is added at ~SDn.

Now, the signals of time slots 5D1-3Dn are switched by the switch group SW to each of the plurality of subordinate exchanges 19, and are applied to the signal rate converter 36 as shown in FIG. 10-1.

Among these, the signal sent to the exchange 1191 is the 10-1
As shown in the figure, it is added to the signal speed increasing circuit group 36a-1 to further increase the signal speed. This is the second
This will be explained using diagram B.

At the lower left of the figure, a signal from the switch group SW enters the signal speed converter 36. The state of the signal speed of this signal is schematically shown. However, in the figure, an arrow indicates one time slot. That is, time slot SDI or 5LJ1 in FIG. 2A is simply indicated by a single arrow.

The two-channel signals indicated by solid and broken arrows are speed-converted by the signal speed converter 36, and this state is shown in the lower right of FIG. 2B.

Figure 2B shows that the signal speed has doubled. To explain the specific circuit that makes this possible, it is exactly the same as the signal speed conversion circuit group 51-1 described above, and it stores the incoming signal and performs it at a higher speed (twice in this case) than when it was stored. This is achieved by reading. On the other hand, the signal output from the exchange 19-1 is input to the signal speed converter 36 from the upper right side of FIG. 2B. The two-channel signals indicated by solid and broken arrows are also stored here, and then read out at a lower speed than when input, the signal speed is reduced, and the signals are separated into each series and input to the switch group SW.

Next, the operation of the signal speed converter 46 installed in the exchange 19 shown in FIG. 10-2 will be explained using FIG. 2C.

Two-channel signals, indicated by solid and broken arrows, coming from the barrier switch 20 are shown at the lower left of FIG. 2C. Again, a signal within one time slot is indicated by a single arrow. This signal is transmitted to the signal speed converter 46
As shown in the lower right of the figure, the signal is slowed down, decomposed into signals compatible with the wireless base station, and sent to the switch group SWb.

It is sent to the wireless base 830, which is the destination of this switch group SWb.

On the other hand, the signal sent from the radio base station 30 and shown in the upper right of the figure is input to the signal speed converter 46 after determining which terminal of the signal speed converter 46 the signal should be sent to by the switch group SWb. Here, the signal speed is increased as shown in the upper left corner of the figure, and the signal is transmitted to the barrier switch 20.

What should be noted in particular about the operation of the signal speed converter 46 or 39 described above is that when the signal speed is increased, the frame length after high speed is generally the shortest frame length among the plurality of incoming TCM signals. On the other hand, in the case of speed reduction, the longest one of the plurality of TCM signals after slowing down becomes equal to the frame length of the original high speed TCM signal.

This is because if the above conditions are not satisfied, and the frame length is made longer than the shortest one even after converting from low speed to high speed, the signals will arrive at the signal speed converter 36 or 46 one after another. , the amount of the output signal is smaller than the amount of the incoming signal, which causes an overflow in the signal rate converter 36, 46. Furthermore, when converting from high speed to low speed, if the frame length is longer than the frame length of the original signal, signal processing will not be able to catch up with the signal input speed and overflow will occur. Under the above conditions, the signal transmitted from the wireless base station 30 after being processed to speed up or slow down is as follows:
As shown in FIG. 2A (a), in the wireless transmission circuit 32 of the wireless base station 30, time slots SDI to SDI
is applied to the modulation circuit as a signal forming one frame.

The time-series multiplexed signal to be transmitted is angularly modulated in the radio transmission circuit 32, and then sent out into space from the antenna section.

When making or receiving a telephone call, the radio base 130
Regarding the transmission of control signals between the mobile radio device 100 and the mobile radio device 100, it is possible to use either within the telephone signal band or outside the telephone signal band.

Figure 3A shows these frequency relationships. In other words, in the figure (a), it is an example of an out-of-band signal, and as shown in the figure,
The low frequency side (250 Hz) or the high frequency side (3850 Hz>) can be used. This signal is used, for example, when it is desired to send a control signal during a call.

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

Although the above examples were all tone signals, it is possible to transmit many types of signals at high speed by increasing the number of tone signals or by modulating the tone and making it into a subcarrier signal.

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 audio signal and time-division multiplex the two to transmit. The circuit configuration of is shown in FIG. 3C. FIG. 3C shows an audio signal digital encoding circuit 9.
This is an example of a case in which the data signal is digitized at 1, multiplexed with a data signal by a multiplex conversion circuit 92, and applied to a modulation circuit included in the wireless transmission circuit 32.

Then, it is received by the opposite receiver, and the 3rd C
By performing the operation opposite to that shown in the figure, it is possible to extract the audio signal and the control signal separately.

On the other hand, the signal sent from the mobile radio device 100 is received by the antenna section of the radio base station 30 and input to the radio reception circuit 35. FIG. 2(b) schematically shows this upstream input signal. That is, time slot SU1. SU2. ...Sun is a mobile radio device 1001
．． 100-2°..., wireless base station 3 from 100-n
Indicates a transmission signal addressed to 0. Also, each time slot su1
．． If the contents of su2, ..., sun are shown in detail, the second
As shown in the lower left part of Figure (b), it consists of a synchronization signal and a call signal or/and a control signal.

However, if the distance between the radio base 830 and the mobile radio device 100 is small or the signal speed is small, the synchronization/synchronization signal may be omitted.

Now, the input signal arriving at the radio base station 30 from the mobile radio device 100 is demodulated in the radio receiving circuit 35 and then transmitted to the exchange 19. Among the signals arriving at the exchange 19, the control signal is immediately applied to the control section 40b of the communication control section 45b. Further, the call signal is applied to the switch group SWb.

Each signal is sent back to the wireless base station 30 by the switch group SWb.
-1.30-2. ..., 3O= or wired telephone 200b
-1 to 200b-Q signals and signal speed converter 46
The signal is divided into a signal going to the barrier switch 20 via the .

Among the divided signals, the signal heading towards the radio base station 30 again is transmitted from the radio base station 30, received by the destination mobile radio device 100, and is converted into an original signal through the process explained in FIG. 1B. will be restored. The signal directed to the wired telephone 200b is also the same as described above.

Furthermore, the exchange function of the barrier exchange 20 will be explained. First, in the case of an incoming call from the telephone network 10 or addressed to the mobile radio device 100, control information is sent from the signal processing section 31 to the communication control section 4.
The received call is transmitted to the control unit 40 of No. 5 to notify the incoming call. In response to this signal, the communication control unit 45 transmits the mobile radio 1 that is being called.
Recognizes which exchange 19's service area 00 is currently in by searching the ID information storage circuit 43 in its own device, and operates the switch group SW, which is an exchange circuit, to receive a call to the corresponding exchange 19. Send a signal.

When there is an incoming call from the telephone network 10 to the telephone set 200, it is processed in the same way as when there is an incoming call to the mobile radio device 100, and the switch group SW switches the transmission lines 21-1 to 21-p. Select one of the backs.

Further, when there is an incoming call to the telephone 200b housed in the exchange 19, the ID information storage circuit 43 is searched, and the switch group SW is operated to send an incoming call signal to the corresponding exchange 19. .

Similarly, regarding an incoming call from the mobile radio 100 to the telephone network 10, the control unit 40b of the exchange 19 that received the call
However, the switch group swb and the signal speed converter 46 are operated to enable transmission and reception with the barrier switch 20, and the barrier switch 20 further connects the line to the telephone network 10.

The aspect of the radio signal used for communication between the radio base station 30 and the mobile radio device 100 will be explained using the required transmission band and the relationship between this and adjacent radio channels.

As shown in FIG. 1A-3, the control signal from the control unit 40b is applied to the wireless transmission circuit 32 of the wireless base 830 together with the output of the switch group SWb.

Next, as shown in FIG. 1B, the mobile radio device 100 also has a circuit configuration required when the radio base station 30 has one communication channel among its functions. Original signal, for example, an audio signal (0.3kHz7~3.0kl-1z
3B shows the frequency distribution on the output side when the signal speed conversion circuit group 5l-1 (FIG. 10-1) passes through the signal speed conversion circuit group 5l-1 (FIG. 10-1). That is, if the audio signal is converted 15 times as described above, the frequency distribution of the signal will be expanded to 4.5kl-(Z~45kl-12) as shown in FIG. 3B.

Although the frequency distribution of the signal is expanded here, the form of the waveform is simply stretched along the frequency axis, and the waveform itself remains unchanged. FIG. 3B shows a case where the control signal is simultaneously transmitted using the lower frequency band of the audio signal.

Among these signals, the control signal (0.2~4.0kt-1z
) and call signal CHI (SD at 4,5~45kH2)
(denoted as I) is accommodated in a time slot, say SDl. The same applies to the audio signals accommodated in the other time slots SD2 to SDn.

That is, time slot SDi (i=2°3, -
, n) accommodates control signals (0.2 to 4.0 kHz) and communication signals @CHi (4.5 to 45 kHz).However, the signals within each time slot are arranged in chronological order. Therefore, signals within a plurality of time slots 1 to 1 are not applied to the wireless transmission circuit 321 at the same time.

These call signals are sent to the wireless transmission circuit 32 along with control signals.
-1, the required transmission band requires at least fC±45kl-1z. However, fo is a radio carrier frequency. If there are a plurality of wireless channels given to the system, the speed-up of the signal by the signal speed conversion circuit group 51-1 is limited to a certain value due to the limitations on these frequency intervals. Let f be the frequency interval of the plurality of wireless channels. , and the maximum signal speed due to the above-mentioned speed increase of the audio signal is fll, then the following inequality must hold between the two.

f > 2 f H ep On the other hand, in digital signals, audio is usually digitized at a speed of about 64 kb/s, so read by raising the scale on the horizontal axis in Figure 3B, which explains the case of analog signals, by about one digit. Although necessary, the relationship in the above equation also holds true in this case.

FIG. 1D shows a specific circuit configuration of telephone 200 (and 200b). This is the mobile radio device 100 shown in FIG. 1B, with the radio circuit removed.
Telephone unit 201. Switch 222'-1, 222-2,
Transmission/reception intermittent controller 223° speed conversion circuit 231. Speed restoration circuit 238. Control unit 240. Clock regenerator 241.
The timing generation type 242 is connected to each mobile radio device 100.
, telephone unit 101. Switches 122-1, 122-2
゜Transmission/reception intermittent controller 123. Speed conversion circuit 131° Speed restoration circuit 138. Control unit 140. Clock regenerator 141
．． It has a function corresponding to the timing generator 142.

The receiving section 235 and the transmitting section 232 have a buffer function for connecting to the transmission line 21 via a hybrid circuit H that performs 2-wire to 4-wire conversion.

The communication signal from the transmission line 21 enters the receiver 235 via the hybrid circuit 1, and the output communication signal is applied to the speed recovery circuit 238 via the clock regenerator 241 and switch 222-1. Ru. Clock regenerator 2
At 41, a clock is recovered from the received signal and applied to the speed restoration circuit 238, the control section 240, and the timing generator 242.

The speed restoration circuit 238 calculates the speed (pitch in the case of an analog signal) of the compressed and segmented communication signal in the received signal.
is restored and input as a continuous signal to the charger section 201 and the control section 240.

The communication signal output from the telephone unit 201 is divided into predetermined time intervals by a speed conversion circuit 231, and the speed (pitch in the case of an analog signal) is made high (compressed) and applied to the transmission unit 232. be done. The output signal of the transmitter 232 is sent to the barrier exchange 20 via the hybrid circuit H2 transmission line 21. To send a signal to switch 19 or barrier switch 20 using the time slots that are allowed to be used, timing generator 242 shown in FIG. 1D is used.
It is necessary that timing information from the controller 240 is obtained via the controller 240.

In this timing generator 242, the clock regenerator 24
1 and a control signal from the control unit 240, the transmission/reception intermittent controller 223 . Necessary timing is supplied to the speed conversion circuit 231 and speed restoration circuit 238.

The telephone 200 has a changeover switch 222-1゜222-
2, and a transmission/reception intermittent controller 22 that generates signals for switching the changeover switches 222'-1 and 222-2, respectively.
3 and a timing generator 242 , and the transmission/reception intermittent controller 223 and the timing generator 242 are controlled by the controller 240 .

Since telephone 200 (or 200b) has such a configuration, it is equivalent to a state in which mobile radio 100 is connected to exchange 19 via radio base station 30. Therefore, the same signal processing and exchange in the switch group SW or SWb can be performed for calling and talking using the mobile radio device 100, except for the processing of radio signals.

Next, the call originating/receiving operation of the system according to the present invention will be explained by taking the case of a voice signal as an example.

(1) Call origination from mobile radio device 100 This will be explained using the flowcharts shown in FIGS. 4A and 4B.

Telephone network 10. The exchange 19, the gateway exchange 20, and the wireless base stations connected thereto have already started operating.
When the power of the mobile radio device 100 is turned on, the radio receiving circuit 135 in FIG.
0 → mobile radio 100) radio channel (channel CH1
start capturing the control signals contained in the If the system is provided with multiple radio channels, i) the radio channel 11) exhibiting the highest received input field;
A wireless channel (iii) that is instructed by a control signal included in the wireless channel; a wireless channel (hereinafter referred to as channel CHI). This is possible by capturing the synchronization signal within the time slot SDi shown in FIG. 2A(a). In the control unit 140, the synthesizer 121-
A control signal is sent to the synthesizer 122-1 to generate a local frequency that enables reception of the radio channel CH1, and the switch 122-1 is also fixed in the position of the synthesizer 121-1.

Therefore, when the receiver of the telephone unit '101 is off-hook (starts making a call) (S201, FIG. 4A), the synthesizer 121-2 of FIG. A control signal to be generated is received from the control unit 140.

Further, the switch 122-2 is also turned to the synthesizer 1212 side and becomes fixed. Next, the calling control signal output from the telephone unit 101 is sent out using the radio channel CH1. This control signal is controlled by the frequency band shown in FIG. 3A(b), e.g.
It is transmitted using n.

The transmission of this control signal is limited to the time slot Sun, and is sent in bursts, and no signal is transmitted during the Sun time slot, so it does not adversely affect other communications. However, if the speed of the control signal is relatively slow or the amount of information in the signal is large and cannot be accommodated in one time slot, the same Sent using time slots.

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 station 30 includes a synchronization signal and a subsequent control signal, and the mobile radio device 100 receives this signal to perform frame synchronization. becomes possible.

Furthermore, this control signal includes control information such as currently used time slots and unused time slots (empty time slot display). Depending on the system, the time slot SDi (+=1.2°...,
n) may only contain synchronization and speech signals when they are being used by other communications; By receiving this control signal, the mobile radio device 100 can know which time slot should be used to send out the calling signal.

Note that if all time slots are in use,
It is not possible to make a call on this radio channel and it is necessary to sweep and search for another radio channel.

In other systems, there may be no empty slot indication in any of the time slots, in which case the following audio multiplex signals SD1, SD2 . ..., S
It is necessary to search for the presence or absence of Dn one after another and check the empty time thrower 1~.

The mobile radio device 100, which has received the control information sent from the radio base station 30 by one of the above methods, determines in which time slot it should send the call control signal and its transmission timing. It is possible to make a judgment including

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 control signals.

Now, if the calling control signal from the mobile radio device 100 is successfully received by the radio base station 30, this information is immediately transmitted to the communication control unit 45b of the exchange 19 via the transmission path. If the ID (identification number) of the mobile radio device 100 is detected (3202), the communication control unit 45b will:
The currently vacant time slot of the radio base station 30 serving the service area where the mobile radio device 100 is present is searched by operating the radio channel information storage circuit 446).

As a result, if time slot SD1 is vacant, for example, time slot uplink (mobile radio device 100 → radio base station 30 )SUI.

and instructs to use the corresponding downlink (radio base station 30 → mobile radio device 100) SDl (3203
>. In response, the mobile radio device 100 transitions to a state in which it can receive data in the instructed time slot SDI, and also shifts to a time slot 5U1 for the uplink radio channel corresponding to the downlink time slot SD1 (see FIG. (
b) Select ). At this time, the control unit 140 of the mobile radio device 100 operates the transmission/reception intermittent controller 123 and starts operating the switches 122-1 and 122-2 (8204>. At the same time, the switch completion report from thrower 1 is sent to the upstream timer. Send to wireless base station 30 using slot SU1 3205>, wait for dial tone (
8206>.

In addition to the time slot SU1, the wireless base station 30 also receives 5LI3 as an uplink signal from another mobile wireless device 100.
and Sun are included in one frame and sent.

The exchange 19 that has received the slot switching completion report via the wireless base station 30 (8207> turns on the switch group SWb and sends a calling signal to the barrier exchange 20.
08), the gateway exchange 20 detects the ID of the mobile radio 100 and turns on the necessary switch among the switch group SW included in the barrier exchange 41120 (
8209>, sends a dial tone (S210.
Figure 4B). This dial tone is transmitted by switch 19. It is transferred by the wireless base station 30 (8211>, and the mobile wireless device 100 confirms that the communication path has been set (32
12>. When this state is reached, a dial tone is heard from the handset of the telephone section 101 of the mobile radio device 100, and the transmission of a dial signal begins. This dial signal is speed-converted by a speed conversion circuit 131 and sent out from a wireless transmission circuit 132 including a transmission section 134 and a transmission mixer 133 using an upstream time slot SU1 (S21
3). Thus, the transmitted dial signal is received by the radio receiving circuit 35 of the radio base station 30 and sent to the communication control section 45b of the exchange 19. The exchange 19 already responds to the calling signal from the mobile radio 100 and determines the time and date to be used.
and the upstream time slot S
It has received U1 and is now in a state of transmitting the signal of downlink time slot SD1. Therefore, mobile radio 1
The dial signal sent from 00 is sent to switch group S.
After passing through Wb, it is input to the signal speed converter 46. Here, after the signal is speeded up as explained using FIG. 2C, it is transmitted to the barrier switch 20. In the gateway exchange 20 that receives this signal, after passing through the switch group SW, it is input to the signal speed restoration circuit group 38, where the original transmission signal is restored and transmitted as a call signal to the telephone network 10 via the signal processing section 31. (S214>. Then, the telephone network 10 sets a call path to the called telephone within the telephone network 10 (S214>.
215>.

On the other hand, input signals from the telephone network 10 (or the telephone 200) (initially a control signal, once a call is started, a call signal) are passed through the signal processing circuit 31 of the barrier switch 20 to the signal speed conversion circuit group 51. The speed conversion signal passes through the switch group SW and is given a time slot SDI. The signal is then sent to the radio base station 30 via the exchange 19 via the transmission path, and is transmitted from the radio transmission circuit 32 to the mobile radio device 100 using the time slot SDI of the downlink radio channel. The mobile radio device 100 is on standby for reception in the time slot SDI of the radio channel CH1, and is received by the radio reception circuit 135, the output of which is input to the speed restoration circuit 138. In this circuit, the original signal of the transmission is restored and input to the handset of the telephone section 101. In this way, a call is started between the mobile radio device 100 and a regular telephone within the regular telephone network 10 (step 3).
216).

To end the call, the handset of the telephone unit 101 of the mobile radio 100 is turned on-hook (S217), and the end-of-call signal and the on-hook signal from the control unit 140 are transmitted to the speed conversion circuit 1.
31 from the wireless transmission circuit 132 to the wireless base station 30 (3218>), and the control unit 140 stops the operation of the transmission/reception intermittent controller 123 and switches 1221 and 122-2 to the synthesizer 1.
It is fixed to the output ends of 21-1 and 121-2.

Meanwhile, the radio base station 30 transfers this signal to the exchange 19. When the communication control unit 45b that controls the exchange 19 receives the call termination signal from the mobile radio device 100, it confirms the termination signal 8219>, turns off the switch group SWb, and at the same time transfers the termination signal to the gateway exchange 20. Shiku 52
20>, when the barrier switch 20 receives this call termination signal (3221), it turns off the switch group SW and ends the call (S222>. At the same time, the signal speed restoration circuit group 38 in the barrier switch 20 and the signal speed Conversion circuit group 51
to open.

(2) Incoming call to mobile radio device 100 The mobile radio device 100 is on standby with the power turned on. In this case, as explained in the section regarding the call origination from the mobile radio device 100, the mobile radio device 100 is in a waiting state to receive a downlink control signal of the radio channel CH1 in accordance with the procedure defined by the system.

Assume that an incoming call signal to the mobile radio device 100 arrives at the barrier switch 20 from the general telephone network 10 . This control signal is immediately transmitted to the communication control section 45.

Then, the communication control unit 45 searches the ID information storage circuit 43, confirms the current location of the mobile radio 100 in each service area of the exchange 19, and then sends a message to the mobile radio 11100 to the exchange 19 that manages the service area. Transfer incoming call information. In the exchange 19 that received this signal, I
After searching the D information storage circuit 43b and confirming the current location of the mobile radio device 100 for each service area of the radio base station 30, searching the radio channel information storage circuit 446) that manages the service area, and moving the mobile radio device 100. An empty slot among the downlink time slots of the radio channel Cl-11 addressed to the radio 100, for example, using SDI, the mobile radio 1
An ID signal of 00, an incoming call signal display signal, and a time slot usage signal @ (for example, SUL corresponding to SDI is used for transmission from the mobile radio device 100) is transmitted via the radio base station 30.

In the mobile radio device 100 that receives this signal, it is transmitted from the receiving section 137 of the radio receiving circuit 135 to the control section 140. In the control unit 140, this signal is transmitted to the own mobile radio device 10.
The telephone unit 10 confirms that it is an incoming call signal to 0.
At the same time, the designated time slot SD1. The transmission/reception intermittent controller 123 is operated to stand by at SU1, and the switch 122-
1. Start turning on and off 122-2. In this way, the state has shifted to a state in which calls can be made.

The above explanation was about a call between the mobile radio device 100 and a telephone in the telephone network 10, but it is also possible to call between a plurality of mobile radio devices 100 or a plurality of telephones 200.
0 and the telephone 200 or between the telephone network 10 and the telephone 20
Communication with 0 can also be performed using the same flow of operations as already described.

In addition, TCM signals can essentially be easily applied not only to telephone calls but also to non-telephone signals such as data and image signals, or to mixed signals thereof, and the system of the present invention communicates these non-telephone signals. It is easy and economical.

(3) Increase in multiple load gain due to increased speed of TCM signals In the system of the present invention described above, telephone signals subjected to TCM are transmitted between the barrier switch 20 and the switch 19 shown in FIGS. 10-1 and 1C-2, for example. In this section, we will theoretically explain why the accelerated TCM signal is used.

In Document 3, to find the multiple load gain in a TCM signal with frame length T〉1/(2rh) (fh is the highest signal frequency included in the telephone signal) and the number of multiplexes n, first, it can be obtained from the following formula. Find the FDM conversion multiplex number n'.

n' - nX1/(2fhT) (1) (Same as equation (19) in Reference 3) Using n' obtained in the above equation to find the multiload gain of the FDM signal that has already been found, is the multiple load gain of the TCM signal with multiplex number ")".

Now, how equation (1) changes as the signal speed increases in the present invention will be explained.

- TC of two TCM signals as shown in Figure 5 by forming a film
The synthesis of Ml and DingCM2 will be explained.

The frame length of TCMl is tl, and the number of time φ slots is m
, TCM2 frame length is t2. The number of time slots is assumed to be n. The multiple load gain when all of these signals are implemented is determined from the FDM conversion multiplex number n' obtained by the following formula.

m' - mx 1/ (2fl, tl) (
2) n' = nx1/(2fh t2 ) (3
) Here, the frame length t1゜t2 as shown in FIG.
(t2≧11) TCM signal TCM1. Find the multiple load gain when TCM2 is combined. As shown <TCM
One frame of l is reduced to m/(m+n)< that of TCM2 is reduced to n/ (m+n>, so (2>,
Equation (3) becomes as follows.

-(m+n) X (2fhil) -1X (m+
n ) (n i 1 ) '= (m+n)x (
2fht1)-1 As is clear from equations (2) to (5), since m''>m'n''>n', the FDM conversion multiplex number is increasing, and therefore the multiple load gain is also increasing. I know that there is. In particular, in TCMI and TCM2, if tl-12-1 m=n (6), then m''-n'-2m-2n (7), and FDM
It can be seen that it is a reversible multiplexing type.

As is clear from the above description, combining TCM signals generally increases the multiload gain. Therefore, in a telephone line with a large number of multiplexes using a CM signal, regardless of whether it is wired or wireless, it is necessary to i) increase the number of multiplexes, ii) shorten the frame length, iii) reduce the maximum frequency of the telephone signal. The multi-load gain increases and economically advantageous signal transmission becomes possible.

In the case of wireless transmission, the above conditions cannot be utilized unlimitedly due to the limitations of the frequency band used, but in the case of wired transmission, the amount of multiple load gain that can be obtained with the current state of technology is as follows, and wireless This is a very large value compared to the system. In addition, the frame length of Document 3>1/(2fh
) does not need to be set in particular, and T≦1/(2fh
), but equation (1) holds true. However, the n calculated using this
If ' is greater than n, it must be n.

Now, in optical fiber transmission, currently 1.6G b
PS high-speed digital transmission has been put into practical use.

When high-speed transmission similar to this is performed using TCM signals, the number of multiple telephones (N number) can be obtained from the following formula.

n = 0.8GHz / 3kHz = 2.67 x
lO'' From the above values, the multiple load gain G is given by the following formula.

G=15+101oan -1541010CI (2,67xlO”)嬌15
-+-54,3=70 (dB) Since the above value is extremely large, the benefits of multiple load gain can be utilized in everything from amplifier design to switching equipment and transmission line design, contributing to economicalization.

Note that the TCM signal configured according to the present invention has good affinity with digital signals. In this case, digital signals generally do not have multiload gain, but for example, a signal in which a CM telephone signal is implemented in the first half of the same frame and a digital signal is implemented in the second half will be explained. In radio section transmission, at the modulator input stage of the transmitter, the modulation is deepened by the amount of the multiple load gain only for the TCM signal subframe, and the modulation is shallowed by that amount for the digital signal subframe before transmission. In addition, if the input level of the subframe of the CM signal is raised by the amount of the multiple load gain, and the amplification operation is performed by lowering the digital signal by that amount, there will be no problem with this composite signal. It is now usable in good condition. The above method provides a new method for simultaneous voice and digital transmission in the I5DN era.

[Effects of the Invention] As is clear from the above description, by applying the present invention to a general telephone network including mobile communication, a small, lightweight, and simple wireless base station circuit can be obtained by obtaining the effect of multiple load gain. In addition to enabling configuration, it saves power and is easy to maintain, and even if the system becomes large-scale and the transmission path becomes longer and the exchange steps become more multi-layered, the TCM signal speed increases, which improves transmission quality and makes it more economical. becomes possible. Furthermore, when telephones are installed in the same network, the transparency of communication within the network improves, and it becomes possible to communicate extremely easily not only by telephone but also by data image signals, so the effects of the present invention are extremely large. It is.

[Brief explanation of the drawing]

Fig. 1A-1 is a block diagram showing the overall configuration of the system of the present invention; Fig. 18-2 is a circuit block diagram that does not show the inside of the barrier switch which is a component of Fig. 1A-1; The figure is a circuit configuration diagram showing the inside of an exchange that is a component of FIG. 1A-1, FIG. 1B is a circuit configuration diagram of a mobile radio device used in the system of the present invention, and FIG. Figure 10-2 is a detailed partial circuit diagram of the barrier switch shown in Figure 2, Figure 10-2 is a detailed partial circuit diagram of the switch shown in Figure 1A-3, and Figure 1D is a detailed diagram of the telephone set used in the present invention. FIG. 2A is a time slot structure diagram for explaining the time slots used in the system of the present invention, and FIG. 2B is a diagram showing the signal speed conversion performed in the barrier switch shown in FIGS. 1A-2. Figure 2C is a time slot array diagram showing how signal speed conversion is performed in the exchange shown in Figures 1A-3; Figures 3A and 3B are A spectrum diagram showing spectra of signals and control signals, FIG. 3C is a circuit configuration diagram for multiplexing audio signals and data signals, FIGS. 4A and 4B are flow charts showing the flow of operation of the system according to the present invention, FIG. 5 is a time slot arrangement diagram showing how to obtain multiple load gain according to the present invention. 10... Telephone network 19... Exchange 20...
・Gateway exchange 21...Transmission line 30...Radio base station 31...Signal processing section 32...Wireless transmission circuit 35...Radio receiving circuit 36...Signal rate conversion section 38...Signal Speed restoration circuit group 39... Signal selection circuit group 40... Control section 41...
- Clock generator 42...Timing generation circuit 43...ID information storage circuit 44...Radio channel information storage circuit 45...Communication control section 46...Signal speed conversion section 51...Signal speed conversion Circuit group 52...Signal allocation circuit group 91...Digital encoding circuit 92...Multiple conversion circuit 100...Mobile radio 101.201...Telephone section 120...Reference crystal oscillator 121-1 , 121-2...Synthesizer 122-1
, 122-2゜222-1, 222-2...Switch 123.223
...Transmission/reception intermittent controller 131.231...Speed conversion circuit 132...Wireless transmission circuit 133...Transmission mixer 1
34... Transmission section 135... Radio receiving circuit 1
36... Reception mixer 137... Receiving section 138.
238...Speed restoration circuit 140.240...Control unit 141.241...Clock regenerator 200...Telephone 232...Transmission unit 235
...Receiving section.

Claims (1)

[Claims] 1. Telephone means (
100, 200) for exchanging the communication signals between the plurality of exchange means (19) and a telephone network (10) connected by a transmission line between the plurality of exchange means. A method for transmitting a time-division communication signal, further comprising a barrier exchange means (20) for increasing the signal speed of the communication signal in the transmission path and multiplexing the communication signal to obtain a multiple load gain. 2. Telephone means (
100, 200) for exchanging the communication signals between the plurality of exchange means (19) and a telephone network (10) connected by a transmission line between the plurality of exchange means. In a transmission system for time-division communication signals, the barrier exchange means speeds up and multiplexes communication signals destined for the plurality of exchange means to obtain a multiple load gain, and transmits the communication signals to the transmission path. a signal speed conversion means (36) for transmitting the communication signal from the telephone means to a signal speed converting means (36) for slowing down and separating the high speed and multiplexed communication signal from the transmission line; A time-division communication signal comprising a signal speed converting means (46) for speeding up and multiplexing the signal and sending it out to the transmission line, and slowing down and separating the speeded up and multiplexed communication signal from the transmission line. transmission system.