JPH1084302A - Wireless communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the wait time for communication start processing by adopting a hopping pattern with a hop number in response to number of communication available communication equipments in the system where 2-way communication is conducted while the frequency is being switched by the frequency hopping system. SOLUTION: A master set 10 decides a hop number Hn in a variable range from L to N sets in response to number of sets in existence in a communication area and whose power supply is turned on, that is, number of communication available equipments among the master set 10 and slave sets 11-15 conducting radio communication by the time division duplex(TDD) system and delivers the hop number Hn to the slave sets 11-15. The master set 10 and the slave sets 11-15 select channels C1, C2,...CL To C1, C2... CN in response to the hop number Hn among all channels C1, C2,...CL,... CM, CN on a hop table and conduct frequency hopping according to the hopping pattern of the hop number Hn. Moreover, in the communication control routine, the hop number Hn is increased in response to the degree of use of voice data, while the hop number Hn is decreased depending on the degree of use of non-voice data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication system for performing bidirectional communication between communication devices while switching frequencies according to a predetermined hopping pattern by a frequency hopping method.

[0002]

2. Description of the Related Art In recent years, a spread spectrum wireless communication system that obtains communication data by despreading and demodulating a received signal while modulating and transmitting communication data after modulation has been developed. Attention has been focused on enabling low power density communications. In particular, when performing frequency hopping in which the frequency is sequentially switched during transmission and reception as a spread spectrum method, signal confidentiality becomes extremely high.Therefore, a spread spectrum wireless communication system to which this frequency hopping is applied is, for example, a telephone or a wireless communication system. It is being widely adopted in various fields such as facsimile machines.

Conventionally, in the radio communication system of the above-mentioned method, the same hop table including hop frequency data indicating a pattern of spreading and despreading for a predetermined channel is provided in all communication devices, and the number of channels in the hop table is set. The communication between the communication devices is performed while performing frequency hopping with a hopping pattern having a hop number equal to. Here, the channel indicates a frequency.

That is, for example, when communication is performed from a master communication device to a specific slave communication device, first,
In the communication start process, a paging signal including ID data of the child device is formed by the parent device, and this paging signal is transmitted as a spread modulation signal while being frequency-hopped every fixed dwell time. At this time, the slave unit is made to stand by so as to despread (receive) a spread modulation signal of a predetermined frequency, and when the spread modulation signal from the master unit is captured by despreading,
Switching of despreading (switching of reception frequency) in accordance with the hopping pattern is performed for each residence time to receive a call signal from the master unit. Thereafter, after establishing synchronization between the master unit and the slave unit, a communication process for continuously transmitting and receiving communication data such as voice data by repeatedly performing frequency hopping of the same pattern in the master unit and the slave unit. Is to be executed.

[0005]

By the way, in a configuration in which communication is performed by frequency hopping with a hopping pattern having a hop number equal to the number of channels (the number of communication frequencies) in the hop table as in the above-described conventional case, FIG. As shown, when one frequency (f4-g4) interferes with each other when communicating between four (two sets) of communication devices 50 to 53, 6
When communication is performed between three (three) sets of the communication devices 50 to 53, interference occurs at other frequencies (for example, f3-g3) other than the frequency (f4-g4). The probability of mutual interaction will increase.

Therefore, conventionally, even when the number of communicable communication devices is set to the maximum number, frequency hopping is performed with a hopping pattern of a hop number corresponding to the maximum number so that the probability of interference is within an allowable range. Measures have been taken. However, in such a measure, as shown in FIG. 14, when the number of communicable communication devices 51 is small, the waiting time during the communication start process is longer than the benefit of reducing the probability of interference. The disadvantage is that the disadvantage becomes greater.

Accordingly, the present invention aims to provide a wireless communication system capable of shortening the waiting time of the communication start process according to the number of communicable communication devices while keeping the probability of interference within an allowable range. Things.

[0008]

In order to solve the above-mentioned problems, a first aspect of the present invention is a radio communication system for performing bidirectional communication between communication apparatuses while switching frequencies according to a predetermined hopping pattern by a frequency hopping method. Wherein the number of hops in the hopping pattern can be changed according to the number of communicable communication devices. This makes it possible to optimize the paging time required for synchronization acquisition by setting a hopping pattern of the number of hops according to the number of communicable communication devices, and simultaneously perform communication between a plurality of communication devices. In this case, the probability that the frequencies between the communication devices interfere with each other can be kept within an allowable range.

A second aspect of the present invention is the wireless communication system according to the first aspect, wherein a specific communication device detects a communicable state of another communication device and responds to the number of communicable communication devices. It is characterized in that the number of hops is transmitted to these communication devices. Thus, the number of hops is transmitted from a specific communication device to another communicable communication device, so that centralized management centering on the specific communication device becomes possible and a system can be easily constructed.

A third aspect of the present invention is the wireless communication system according to the first or second aspect, wherein a hopping pattern of a required hop number is formed from a hop table corresponding to a maximum hop number. By having a hop table corresponding to the maximum number of hops, when a required number of hops is obtained, a hopping pattern corresponding to the number of hops can be easily formed.

A fourth aspect of the present invention is the radio communication system according to any one of the first to third aspects, wherein the number of hops is increased in accordance with an increase in the number of communication devices used for voice signal communication. And Thereby, high confidentiality, which is a great merit for the audio signal, can be obtained by increasing the number of hops.

A fifth aspect of the present invention is the radio communication system according to any one of the first to third aspects, wherein the number of hops is reduced as the number of communication devices used for non-voice signal communication increases. Features. As a result, one cycle of hopping is shortened due to a decrease in the number of hops, and a call time required for synchronization acquisition is shortened, so that communication of a non-voice signal can be completed in a short time.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 3, the wireless communication system according to the present embodiment has one master device 10 (communication device) connected to an external line, and can communicate with the master device 10 and can communicate with each other. Units 11-15
(Communication device). Note that a telephone, a facsimile device, a printer, a computer, and the like can be applied to the master device 10 and the slave devices 11 to 15. Communication between master device 10 and slave devices 11 to 15 and communication between slave devices 11 to 15 are, as shown in FIG.
uplex) system, and when one is in the transmission state (TX), the other is in the reception state (RX), and communication is performed by alternately replacing the transmission state (TX) and the reception state (RX). It is supposed to do.
Note that this wireless communication system uses TDMA (Time Division M
The communication may be performed by a utipke access) method.

The above-mentioned master unit 10 and slave units 11 to 15
As shown in FIG. 5, there is a wireless communication unit 1 for transmitting and receiving communication data by a spread spectrum method while frequency hopping. The wireless communication unit 1 has an interface unit 21 that processes and inputs and outputs communication data to and from an external circuit (not shown). Interface unit 2
1 has a codec and a compressor for mutually converting between a voice signal and a digital signal when the communication data is a voice signal, while, when the communication data is a non-voice signal,
It has a buffer and a data converter for performing error correction processing and the like.

The interface section 21 is connected to a modulator / demodulator 22 having a modulator 22a for modulating communication data and a demodulator 22b for demodulating communication data. The modulator / demodulator 22 switches the operating state of the modulator 22a and the demodulator 22b between transmission and reception of communication data by a transmission command signal p and a reception command signal q from the controller 35. Then, the modulation section 22a operated at the time of transmission is connected to an up-converter 23 having a mixer.

The up converter 23 includes a PLL.
A local oscillator 25 is connected to the PLL local oscillator 2
5, hop frequency data f1 and f for a plurality of channels (frequency) C1, C2, ..CL, ..CM, ..CN as shown in FIG.
A hop table 26 storing 2, .. fL, .. fM, .. fN is connected. These hop tables 26 and PLL
A hop signal r is input to the local oscillator 25 every predetermined dwell time from the controller 35,
The hop table 26 stores the hop frequency data f corresponding to the channel (frequency) of the channel setting value S indicated by the hop signal r every time the hop signal r is input.
The hop frequency signal s having a frequency corresponding to the hop frequency data f is output from the PLL local oscillator 25 to the up-converter 23. Then, the up-converter 23 adds the hop frequency signal s from the PLL local oscillator 25 and the modulation signal t of the communication data from the modulation unit 22a to form a spread modulation signal u that hops in frequency. ing.

The up converter 23 is connected to a transmission / reception switch 27 via a power amplifier 24 for amplifying the spread modulation signal u. The transmission command signal p and the reception command signal q are input from the controller 35 to the transmission / reception switch 27. When the transmission designation signal p is input, the operation state is set to the transmission enabled state and the power amplifier 24 Is transmitted from the antenna 28. On the other hand, when the reception command signal q is input, the operation state is set to the receivable state, and the spread modulation signal u received via the antenna 28 is output to the low noise amplifier 31.

The low-noise amplifier 31 is connected to a down-converter 32.
Is amplified and output. The down-converter 32 receives the hop frequency signal s input to the up-converter 23 from the PLL local oscillator 25. The down-converter 32 generates a spread modulation signal based on the hop frequency signal s. The modulated signal t is formed by despreading u, and the modulated signal t is output to the demodulation unit 22b. The demodulation unit 22b demodulates the input modulated signal t and outputs the demodulated signal t to the interface unit 21.

The wireless communication unit 1 having the above configuration operates by being supplied with power from a power supply unit 36. The power supply unit 36 controls a part or the controller 35 before a communication start process. The power supply destination is set by the controller 35 so as to limit the power supply to all the wireless communication units 1 except for the power supply destination. That is, the controller 35 controls so as to supply power only to the controller 35 in the sleep mode, and controls so as to supply power except for the transmission unit including the up-converter 23 and the power amplifier 24 in the reception standby mode. In the mode, control is performed to supply power to the entire wireless communication unit 1. Further, even in the communication mode, the power may be supplied except for the up-converter and the power amplifier at the time of reception and excluding the low-noise amplifier and the down-converter at the time of transmission.

The controller 35 for controlling each section as described above executes the communication control routine shown in FIG. The communication control routine includes a paging process for transmitting a paging signal and a receiving process for receiving a paging signal so as to establish synchronization of the spread modulated signal u with the specific base unit 10 or the subunits 11 to 15 in the communication start process. After performing standby processing and establishing synchronization of the spread modulation signal u, the processing shifts to communication processing for transmitting and receiving audio data and the like.

As shown in FIGS. 1 and 2, this communication control routine hops according to the number of communicable master units 10 and slave units 11 to 15 (hereinafter referred to as communicable units). The number of hops in the pattern is changed in a range from L to N, and after the master device 10 designated as the specific communication device determines the hop number according to the number of communicable devices, The number of hops is transmitted to the slave units 11 to 15 designated as the communication units.

That is, in the base unit 10, the number of hops Hn is determined in a variable range from L to N according to the number of communicable units, and this hop number Hn is transmitted to the slave units 11 to 15. The master unit 10 and the slave units 11 to 15 select the channels C1, C2,... According to the hop number Hn from among all the channels C1, C2,. CL ~ C1, C2, .. CN
Is selected, and frequency hopping is performed with a hopping pattern of the hop number Hn. The state in which the master unit 10 and the slave units 11 to 15 are not communicable means that the power supply is off due to insufficient charging or the like or that the master unit 10 and the slave units 11 to 15 are outside the communication area. Fifteen
This is a state in which transmission and reception of radio waves are disabled between devices.

Further, the communication control routine includes the master unit 1 used for voice data communication together with the number of communicable units.
The number of hops Hn of the hopping pattern is changed according to 0 and the number of slaves 11 to 15, and the master 10 and slaves 11 to 11 used for voice data communication.
While increasing the number of hops in accordance with the increase of the number 15, the parent device 10 and the child devices 11 to 15 used for communication of non-voice signals
The number of hops Hn is reduced as the number of hops increases.

Thus, when the master unit 10 and the slave unit 11 having the maximum communicable number are used for non-voice, the minimum hop number Hn (L) of the hop table 26 is used.
Is used to form the hopping pattern. When the master unit 10 and all the slave units 11 to 15, which are the maximum communicable units, are used for voice, the maximum hop number Hn of the hop table 26 is used. The hopping pattern is formed by using (N pieces).

The operation of the wireless communication system in the above configuration will be described with reference to the flowcharts of FIGS.

First, as shown in FIGS. 5 and 6, when the controller 35 executes the sleep mode, the power supply from the power supply section 36 is limited to only the controller 35, and the power consumption is suppressed to a necessary minimum. (S
1). The controller 35 receiving the power supply continues to execute the communication control routine, and determines whether or not an instruction to make a call is made by checking the operation state of a call switch (not shown) or the like (S2). If it is determined that a call is to be made (S2, YES), a call process (S5) of FIG. 9 for communicating with the called slaves 11 to 15 (S5).
0), if it is determined that the calling is not to be performed (S2, NO), it is determined whether or not the time is up after elapse of a predetermined time using an internal timer or the like (S2).
3) If the time is not up (S3, NO), S
1 sleep mode is continued. On the other hand, when the time is up (S3, YES), the mode is set to the reception standby mode, and the power supply unit 36 transmits the signal to the transmission unit (upconverter
3. Power supply is started except for the power amplifier 24) (S4).

Then, the controller 35 outputs a reception command signal q to the modem 22 and the transmission / reception switch 27, thereby setting the demodulation unit 22b of the modem 22 to the operation state and setting the transmission / reception switch 27 to the reception state. Set. Also, the hop signal r whose channel set value S is “1”
Is output to the hop table 26 and the PLL local oscillator 25. For example, the hop frequency data f1 of the first channel C1 is output to the PLL local oscillator 25 with respect to the hop table 26, and the frequency corresponding to the hop frequency data f1 ( f1) hop frequency signal s to PLL local oscillator 2
5 to the down-converter 32. Then, the down-converter 32 is set to perform despreading at the frequency (f1), and the spread modulation signal u at the frequency (f1) is set in a receivable state and waits (S5).

As shown in FIG. 11, when the above-mentioned frequency (f1) is interfered, a process of waiting for reception at one of the remaining frequencies (f4) is performed at a predetermined frequency (f4). Is repeated until the calling slave units 11 to 1
It is desirable to start frequency hopping after receiving the signal from S.5.

Next, it is determined whether or not a call has been received by receiving the above spread modulation signal u (S6). If a call has been received (S6, YES), the handset handsets 11 to 1 are called.
The response processing of FIG.
0). On the other hand, if the call has not been received (S6, N
O), by executing the operation state confirmation processing (S7 to S12), the operation states of all the registered slave units (child units 11 to 15) registered in advance in the master unit 10 are checked.

That is, a calling process is performed on the first slave unit 11 in FIG. 3 (S7), and it is determined whether or not there is a response from the slave unit 11 on the called side (S8). If there is a response (S
8, YES), the operation state of the slave unit 11 is registered as an active state (S9). On the other hand, if there is no response (S
8, NO), it is determined whether or not the slave unit 11 is communicating (S10). If the slave unit 11 is communicating (S10, YES), the operation state of the slave unit 11 is registered as an active state (S9). ). On the other hand, if communication is not in progress (S10, NO),
The operation state of the slave unit 11 is registered as an off state (S
11).

Thereafter, it is determined whether or not there is a registered slave unit whose operation status has not been confirmed (S12), and as in the second to fifth slave units 12 to 15 in FIG. Exists (S12, YES), the operation state is confirmed also for the second to fifth slave units 12 to 15 by re-executing from S7. Thereafter, when the operation states of all the slave units 11 to 15 have been checked and there are no unchecked registered slave units (S12, NO), the hop number Hn according to the number of slave units in the active state or the like. Is started (S20).

More specifically, as shown in FIG. 7, the number of active slave units is obtained by counting the number of registered slave units in the active state (S21). Then, by comparing the number of active slaves before the operation state confirmation processing in FIG. 6 with the number of active slaves obtained in S21, it is determined whether or not the number of active slaves has changed (S22).
If no change has occurred (S22, NO), the process returns to the communication control routine of FIG. 6 and shifts to the sleep state of S1.

On the other hand, if the number of active slave units has changed (S22, YES), it is determined whether the number of active slave units has increased (S23). If the number of active slaves has increased (S23, YES), the first hop number determination process (S24 to S32) is executed, and if the number of active slaves has not increased (S23, NO),
The second hop number determination processing (S40) is executed. And
By executing the first hop number determination process and the second hop number determination process, the number of hops Hn is determined based on the number of registered slave units in the active state and the content of communication data.

In the above first hop number determination processing,
First, a registration number i indicating each registered slave unit (slave units 11 to 15)
H is set to "1" (S24). Then, it is determined whether or not the registered slave unit of the registration number iH is in the active state (S25).
O) If the current hop number Hn is maintained and the active state is maintained (S25, YES), then it is determined whether or not this registered slave unit is used for voice (S26). If it is for voice (S26, YES), it is determined whether the hop number Hn is the maximum (S27), and if it is the maximum (S2).
7, YES), the current hop number Hn is maintained, and if not the maximum (S27, NO), a predetermined number T is added to the current hop number Hn (S28). On the other hand, in S26, when it is determined that the registered slave unit with the registration number iH is not used for voice (S26, NO), subsequently, it is determined whether the hop number Hn is minimum (S26). (S29) If it is the minimum (S29, YES), the current hop number Hn is maintained, and if it is not the minimum (S29, NO), a predetermined number T is subtracted from the current hop number Hn (S30).

Thereafter, in S25 to S30, when the hop number Hn is determined based on the operation state of the registered slave unit of the registration number iH and the contents of the communication data, "1" is added to the registration number iH ( S31), it is determined whether or not this registration number iH is equal to or less than the maximum registration number iHmax indicating the last registered slave unit (S32). When it is determined that the registration number iH is equal to or smaller than the maximum registration number iHmax (S32, Y
ES), re-executing from S25 described above, and subsequent registration number i
The calculation of the hop number Hn based on the registered child device of H is repeated. Then, when the calculation of the hop number Hn based on the registered child device of the maximum registration number iHmax is completed and it is determined that the registration number iH has exceeded the maximum registration number iHmax (S32, YE
S), the final hop number Hn is notified to each registered child device in the active state (S33).

If it is determined in S23 that the number of active slave units has not increased (decreased) (S23, NO), a second hop number determination process is executed (S40). When the second hop number determination process is executed, FIG.
As shown in (1), first, "1" is set to the registration number iH indicating each registered slave unit (slave units 11 to 15) (S41). Then, it is determined whether or not the registered slave unit with the registration number iH is in the active state (S42). If it is not in the active state (S42, NO), the current hop number Hn is maintained. (S42, YES) Then, it is determined whether or not this registered slave unit is used for voice (S43). If it is for voice (S43, YES), it is determined whether the hop number Hn is minimum (S44). If it is minimum (S44, YES), the current hop number Hn is maintained and must be minimum. If (S44, NO), the predetermined number T is subtracted from the current hop number Hn (S45). On the other hand, S4
In step S3, if it is determined that the registered slave unit having the registration number iH is not used for audio (S43, NO),
Subsequently, it is determined whether or not the hop number Hn is the maximum (S
46), if it is maximum (S46, YES), the current hop number Hn is maintained; if it is not maximum (S46, NO),
A predetermined number T is added to the current hop number Hn (S47).

Thereafter, in S41 to S47, when the number of hops Hn is determined based on the operation state of the registered slave unit of the registration number iH and the content of the communication data, "1" is added to the registration number iH ( S48), it is determined whether or not this registration number iH is equal to or less than the maximum registration number iHmax indicating the last registered slave unit (S49). When it is determined that the registration number iH is equal to or less than the maximum registration number iHmax (S49, Y
ES), re-executing from S42 described above, and subsequent registration number i
The calculation of the hop number Hn based on the registered child device of H is repeated. Then, when the calculation of the hop number Hn based on the registered child device of the maximum registration number iHmax is completed and it is determined that the registration number iH has exceeded the maximum registration number iHmax (S49, YE
S), returning to the hop number setting processing routine of FIG.
The finally calculated hop number Hn is notified to each registered child device in the active state (S33).

When the number of hops Hn is transmitted to each registered child device as described above, the process returns to the communication control routine of FIG. 6 and shifts to the sleep state of S1. If it is determined in S2 that a call is to be made (S2, YE
S), a calling process is executed (S50). When the calling process is executed, first, as shown in FIG. 9, the communication mode is set, the power supply unit 36 in FIG. 5 starts power supply to each unit of the wireless communication unit 1, and the hop table 26 in FIG. The maximum channel count value Cmax is set to “hop number Hn”, the channel set value S is set to “1”, and the channel count value C is set to “1” so that the hopping pattern has a variable range corresponding to the hop number Hn ( S51).

Thereafter, the controller 35 outputs the transmission command signal p to the modulator / demodulator 22 and the transmission / reception switch 27, thereby setting the modulation section 22a of the modem 22 to the operation state and setting the transmission / reception switch 27 to the transmission state. Set to.
Further, by outputting the hop signal r having the channel setting value “1” to the hop table 26 and the PLL local oscillator 25, the hop frequency data f1 of the first channel C1 is transmitted to the hop table 26 by the PLL local oscillator. The PLL local oscillator 25 outputs the hop frequency signal s having a frequency (f1) corresponding to the hop frequency data f1 to the up converter 23 and the down converter 32.

Next, the parent device 10 and the child devices 11 to 1 on the called side are called.
5 is taken into the modem 22 via the interface unit 21 and modulated by the modulation unit 22a, and then converted into a modulated signal t.
Output to 3. Then, in the up-converter 23, the modulation signal t and the hop frequency signal s from the PLL local oscillator 25 are added to form a spread modulation signal u. Thereafter, the spread modulation signal u is transmitted to the power amplifier 24.
After amplification by the antenna 28 via the transmission / reception switch 27
(S52).

When the call transmission is completed in S52, the controller 35 transmits the reception command signal q to the modulator / demodulator 22.
By setting the output to the transmission / reception switch 27, the demodulation unit 22b of the modem 22 is set to the operation state, the transmission / reception switch 27 is set to the reception state (S53), and the response signal from the called side is received. Is determined (S5).
4). If there is no response (S54, NO), the channel count value C becomes the maximum channel count value Cmax.
It is determined whether the value is smaller than (“hop number Hn”) (S55), and if it is smaller (S55, YE).
S) While the channel set value S and the channel count value C are counted up by "1" (S56), if not small (S55, NO), the channel set value S and the channel count value C are reset to "1". (S57). When a predetermined dwell time elapses by an internal timer or the like (not shown), the channel set value S
Is transmitted to the hop table 26 and the PLL.
After output to the local oscillator 25 and frequency hopping (S58), the process is re-executed from S52 to continue the calling process.

Next, when a response signal from the called side is received (S54, YES), the channel count value C
Is the maximum channel count value Cmax (“Hop number H
n ”) is determined (S5).
9) If the value is small (S59, YES), the channel set value S and the channel count value C are counted up by "1" (S60). If not (S59, NO), the channel set value S is incremented. And the channel count value C is reset to "1" (S61). When a predetermined dwell time elapses by an internal timer (not shown) or the like, a hop signal r indicating the channel set value S is transmitted to the hop table 26 and the PLL local oscillator 25.
And performs frequency hopping (S62), and transmits (S63) and receives (S64) communication data with a spread modulated signal u having a frequency corresponding to the hop frequency data fS of the channel set value S. Then, it is determined whether or not the communication has been completed (S65), and if not completed (S65, N
O) By re-executing from S59, transmission / reception of communication data is continued while repeating frequency hopping for each residence time, and when communication is completed (S65, YES), the process returns to the communication control routine of FIG. 6 and returns to S1. Go to sleep state.

In S6 of FIG. 6, it is determined that a call has been received (S6, YES), and when the response process of S70 is executed, as shown in FIG. 10, ID data of the calling side is included. A response signal is transmitted (S71). After this,
When the synchronization is established at the time of the communication start processing, the maximum channel count value Cmax is set to the "hop number Hn" so that the communication processing is started (S72). Thereafter, the channel count value C becomes the maximum channel count value Cmax.
It is determined whether the value is smaller than (“Hn”) (S73). If the value is small (S73, YES), the channel set value S and the channel count value C are counted up by "1" (S74). If not (S73, NO), the channel set value S and the channel count are counted. The value C is reset to “1” (S7
5). Then, when a predetermined dwell time elapses by an internal timer (not shown) or the like, a hop signal r indicating the channel set value S is output to the hop table 26 and the PLL local oscillator 25 and frequency hopped (S7).
6) The communication data is received (S77) and transmitted (S78) with the spread modulated signal u of the frequency (fs) corresponding to the hop frequency data fs of the channel set value S. Then, it is determined whether or not the communication has ended (S79). If the communication has not ended (S79, NO), transmission and reception of communication data are continued while repeating frequency hopping for each residence time, and when the communication ends (S79). , YES), the process returns to the communication control routine of FIG. 6, and shifts to the sleep state of S1.

As described above, in the wireless communication system of the present embodiment, as shown in FIG. 1, the communication devices (master device 10 and slave devices 11 to 15) switch the frequency according to a predetermined hopping pattern by the frequency hopping method. When bidirectional communication is performed between each other, the hop number Hn of the hopping pattern can be changed in a variable range from L to N according to the number of communicable communication devices. Thus, the hopping pattern of the hop number Hn corresponding to the number of communicable communication devices can optimize the paging time required for synchronization acquisition. Also, when simultaneous communication is performed between a plurality of communication devices, the probability that the frequencies between the communication devices interfere with each other can be kept within an appropriate range.

The radio communication system according to the present embodiment
A specific communication device (parent device 10) is connected to another communication device (child devices 11 to 11).
15), the communicable state is detected, and the number of hops Hn corresponding to the number of communicable communication devices is determined by these communicators (child devices 11 to 1).
5). As a result, a specific communication device (master device 10) can communicate with another communication device (child devices 11 to 1).
Since the number of hops Hn is transmitted to 5), centralized management centering on a specific communication device (parent device 10) becomes possible, and a system can be easily constructed.

The radio communication system according to the present embodiment
As shown in FIG. 2, the hopping pattern of the required hop number Hn (L to N) is formed from the hop table 26 corresponding to the maximum hop number Hn (N).
Thus, by having the hop table 26 corresponding to the maximum hop number Hn (N), when the required hop number Hn (M) is obtained, the hop number Hn
Hopping patterns corresponding to (M) hopping patterns can be easily formed.

Further, the wireless communication system of the present embodiment
Communication device (slave device 11-15) used for voice signal communication
The number of hops Hn increases as the number of hops increases, and the number of hops Hn decreases as the number of communication devices (child devices 11 to 15) used for non-voice signal communication increases. As a result, high confidentiality, which is a great merit for voice signals, can be obtained by increasing the number of hops Hn. Since the communication of the non-voice signal can be completed in a short time, the number of hops Hn can be set more finely.

In the present embodiment, the master unit 10 is set to be in the sleep state after the end of the communication processing. However, the present invention is not limited to this, and is always in the standby state as shown in FIG. May be. In this case, when the master unit 10 or the slave unit 11 is used in a frequently accessed mode such as a server or a printer, high-speed access is possible, so that communication can be completed in a short time. Can be. Further, it is not necessary to always wait for reception at the same frequency (f1), and it may be arranged to wait for reception at a random frequency every time exiting from the sleep mode. Further, the operation state confirmation processing and the hop number setting processing of FIG. 6 in the present embodiment may be performed periodically or may be performed during a time period when the traffic is small. .

[0049]

According to the first aspect of the present invention, there is provided a wireless communication system for performing two-way communication between communication devices while switching frequencies according to a predetermined hopping pattern by a frequency hopping method. The hop number of the hopping pattern can be changed accordingly. This makes it possible to optimize the paging time required for synchronization acquisition by setting a hopping pattern of the number of hops according to the number of communicable communication devices, and simultaneously perform communication between a plurality of communication devices. In this case, there is an effect that the probability that the frequencies between the communication devices interfere with each other can be kept within an allowable range.

According to a second aspect of the present invention, there is provided the wireless communication system according to the first aspect, wherein a specific communication device detects a communicable state of another communication device and responds to the number of communicable communication devices. In this configuration, the number of hops is transmitted to these communication devices. As a result, the number of hops is transmitted from a specific communication device to other communicable communication devices, so that centralized management centering on the specific communication device becomes possible, and the system can be easily constructed. To play.

A third aspect of the present invention is the wireless communication system according to the first or second aspect, wherein a hopping pattern of a required hop number is formed from a hop table corresponding to the maximum hop number. Thus, by having a hop table corresponding to the maximum number of hops, when the required number of hops is obtained, it is possible to easily form a hopping pattern corresponding to the number of hops.

A fourth aspect of the present invention is the radio communication system according to any one of the first to third aspects, wherein the number of hops increases as the number of communication devices used for voice signal communication increases. . Thereby, there is an effect that high confidentiality, which is a great merit for the audio signal, can be obtained by increasing the number of hops.

According to a fifth aspect of the present invention, in the wireless communication system according to any one of the first to third aspects, the number of hops decreases as the number of communication devices used for non-voice signal communication increases. is there. As a result, one cycle of hopping is shortened due to the decrease in the number of hops, and the ringing time required for synchronization acquisition is shortened, so that the communication of non-voice signals can be completed in a short time.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a hopping pattern that changes the number of hops according to the number of communicable devices and communication content.

FIG. 2 is an explanatory diagram showing data contents of a hop table.

FIG. 3 is an explanatory diagram showing a relationship between a parent device and a child device.

FIG. 4 is an explanatory diagram showing a communication mode according to the TDD scheme.

FIG. 5 is a block diagram of a wireless communication unit.

FIG. 6 is a flowchart of a communication control routine.

FIG. 7 is a flowchart of a hop number setting processing routine.

FIG. 8 is a flowchart of a second hop number determination processing routine.

FIG. 9 is a flowchart of a call processing routine.

FIG. 10 is a flowchart of a response processing routine.

FIG. 11 is an explanatory diagram of a hopping pattern during a communication start process and a communication process.

FIG. 12 is an explanatory diagram of a hopping pattern during communication start processing and communication processing.

FIG. 13 illustrates a conventional example, and is an explanatory diagram of a hopping pattern during communication start processing and communication processing.

FIG. 14 illustrates a conventional example, and is an explanatory diagram of a hopping pattern during communication start processing and communication processing.

[Explanation of symbols]

 Reference Signs List 1 wireless communication unit 10 master unit 11-15 slave unit 21 interface unit 22 modem 23 up converter 24 power amplifier 25 PLL local oscillator 26 hop table 27 transmission / reception switch 28 antenna 31 low noise amplifier 32 down converter 35 controller 36 power supply unit

Claims (5)

[Claims] 1. A wireless communication system for performing bidirectional communication between communication devices while switching a frequency according to a predetermined hopping pattern by a frequency hopping method, wherein the hopping of the hopping pattern depends on the number of communicable communication devices. A wireless communication system wherein the number is changeable. 2. The communication device according to claim 1, wherein the specific communication device detects a communicable state of another communication device and transmits a hop number corresponding to the number of communicable communication devices to these communication devices.
A wireless communication system as described. 3. The wireless communication system according to claim 1, wherein a hopping pattern of a required hop number is formed from a hop table corresponding to a maximum hop number. 4. The wireless communication system according to claim 1, wherein the number of hops increases as the number of communication devices used for voice signal communication increases. 5. The wireless communication system according to claim 1, wherein the number of hops decreases as the number of communication devices used for non-voice signal communication increases.