JP6072337B1 - Wireless communication apparatus and wireless communication system - Google Patents

Abstract

Provided is a wireless communication system capable of simultaneous communication with three parties capable of transmitting at an antenna power of 10 mW that satisfies carrier sense regulations and capable of integrating or eliminating a parent device in a small size. A slave unit for a simultaneous communication radio communication system including a master unit that operates as a relay unit and three slave units transmits and receives a radio signal on a pair channel by performing carrier sense. And sub-receiving means for receiving a radio signal on a channel different from the pair channel. The base unit performs carrier sense and transmits / receives a radio signal through a predetermined pair channel, and a channel other than the pair channel and one of three different channels. Three sub-reception means for receiving radio signals, and each radio signal received by each sub-reception means are demodulated and each audio signal demodulated is added and mixed, and the added audio signal is sent to the transmission means. Audio mixing means for outputting. [Selection] Figure 3

Description

  The present invention relates to a wireless communication device that performs simultaneous calls with other wireless communication devices, and a wireless communication system that includes a plurality of wireless communication devices that perform simultaneous calls.

  Aiming at the convenience of wireless device manufacturers and users, such as ensuring appropriate quality and compatibility of radio equipment, together with national technical standards for the purpose of effective use of frequencies and avoidance of interference with other users Therefore, “Specified low power radio station radio equipment radio equipment standard” is defined in Non-Patent Document 1. This specific low-power radio station is widely used nationwide because it does not require a radio station license.

  On page 2 of Non-Patent Document 1, it can be classified into “basic type” and “area expansion type” as the operation mode of the standard system, and “opposite type” and “centralized base type” are disclosed as the “basic type”. . Also, on pages 4 to 9 of Non-Patent Document 1, the frequency band, antenna power, number of channels, and frequency used are defined using the “broadcast communication method” or “duplex communication method” communication method for simultaneous communication. ing.

  Hereinafter, a configuration example of a wireless communication system according to a conventional example in which simultaneous calls are performed will be described. In the following conventional examples and examples, an example will be described based on the use frequency and channel defined in Non-Patent Document 1. In the drawing, for example, 454 MHz band CHA represents 454 MHz band channel A, and so on.

  FIG. 1 is a block diagram showing a configuration example of a wireless communication system according to Conventional Example 1. The wireless communication system of FIG. 1 includes a parent device 110 that is a relay device and three child devices 101 to 103, for example. Here, the subunit | mobile_units 101-103 are provided with the 1 mW radio | wireless transmission part which has a mutually different transmission frequency, and the radio | wireless receiving part which has the mutually same receiving frequency. On the other hand, base unit 110 has a radio transmission unit having the same transmission frequency as the reception frequency of the radio reception units of slave units 101 to 103, and a reception frequency that is the same as the transmission frequency of the radio transmission unit of each of slave units 101 to 103. And an adder 111 that adds and mixes the audio signals from the three wireless receivers and outputs the result to the wireless transmitter. By configuring as described above, a simultaneous communication radio communication system is configured.

  FIG. 2 is a block diagram showing a configuration example of a wireless communication system according to the second conventional example. The wireless communication system of FIG. 2 includes a parent device 210 that is a relay device and, for example, three child devices 201 to 203. Here, the subunit | mobile_unit 201-203 is provided with the 10 mW radio | wireless transmission part and radio | wireless receiving part which have the transmission / reception frequency of a mutually different pair channel. On the other hand, base unit 210 has relay device 211 that performs simultaneous call communication with handset 201, relay device 212 that performs simultaneous call communication with handset 202, relay device 213 that performs simultaneous call communication with handset 203, and relay. The adder 214 adds and mixes the audio signals from the respective radio reception units of the devices 211 to 213 and outputs them to the distributor 215, and the audio signal from the adder 214 is transmitted to the 10 mW radio transmission units of the relay devices 211 to 213. And a distributor 215 for outputting to distribute. By configuring as described above, a simultaneous communication radio communication system is configured.

  Incidentally, wireless communication systems having the basic configuration of Conventional Example 1 are disclosed in Patent Documents 1 to 3 below.

  In Patent Document 1, an audio signal obtained by adding the output signals of a plurality of reception demodulation means is added to and added to the output signal of the reception demodulation means of another wireless repeater, whereby the wireless repeater is completed as a product. There has been disclosed a wireless repeater that can theoretically increase the number of wireless communication devices that can be simultaneously talked to infinitely. The radio repeater includes a plurality of reception demodulation means for receiving radio waves and demodulating an audio signal, an external input terminal for inputting the audio signal, and each demodulation output by the plurality of reception demodulation means. A mixer for adding the signal and the audio signal input from the external input terminal, a modulation transmission means for modulating the audio signal and transmitting it as a radio wave, and a switch for operating or stopping the modulation transmission means And an external output terminal for outputting the audio signal added by the mixer to the outside.

  Further, in Patent Document 2, a radio repeater is manufactured as a product by modulating and transmitting an audio signal obtained by adding the output signals of a plurality of reception demodulation means as a reception frequency of one reception demodulation means inside another radio repeater. There has been disclosed a wireless repeater that can theoretically increase the number of wireless communication devices that can simultaneously talk even after completion. The wireless repeater includes a plurality of reception demodulation means for receiving radio waves and demodulating an audio signal, a mixer for adding the demodulated signals output by the plurality of reception demodulation means, and an audio signal. Modulation transmission means for modulating and transmitting as a radio wave, and one reception frequency shared by a plurality of wireless communication devices as the first transmission frequency of the modulation transmission means, and in one wireless repeater other than its own station A frequency setting means capable of setting the reception frequency of one reception demodulation means as a second transmission frequency of the modulation transmission means, and a switch capable of selecting the first and second transmission frequencies. .

  Furthermore, in Patent Document 3, all wireless devices can receive the contents of simultaneous calls between parent and child or between child devices via a parent device having a relay function, and other child devices are used for calling even during simultaneous calls. An inexpensive multi-radio simultaneous call system capable of emitting a radio wave is disclosed. In the multi-radio simultaneous call system, at least two repeaters 1 each uniquely assigned with a reception channel frequency and a transmission channel frequency are mutually connected by a relay cable as a parent device that relays the contents of simultaneous calls to a child device. Connected and controlled by the control unit, the microphone input signal from the microphone amplifier, the received signal from the slave unit received by the receiver, the input signal via the relay cable from other repeaters, and among these signals From any one of the mixed signals obtained by mixing the signals selected by the first selector with the mixer, the second selector selects the signals from the transmitter as a call signal for all the slave units, In addition, it is selected by the third selector and transmitted to another repeater via a relay cable.

JP 2009-010900 A JP 2009-1000043 A JP 2007-096579 A

Radio Industry Association, “Specified Low Power Radio Station Radio Equipment Standards”, RCR-STD-20 4.1 Edition, revised on November 30, 2005

By the way, on page 13 of Non-Patent Document 1, “career sense” is defined as follows (former notification of the Ministry of Posts and Telecommunications, No. 49 of 1989). Hereinafter, it is referred to as “career sense rules”.
“(3) Carrier Sense Radio equipment shall be equipped with carrier sense. Carrier sense is the same as the radio wave emitted by another radio station when it receives radio waves from other radio stations prior to setting up the radio communication line. It shall not emit radio waves of the frequency (the transmission frequency corresponding to the reception frequency in the case of the duplex system and the half-duplex system.) For the antenna power of 1 mW or less, the communication system is duplex. The carrier sense can be performed at the transmission frequency of the local station even in the case of the method and the half-duplex method, but radio waves having frequencies of 413.7 MHz to 414.1375 MHz and 454.05 MHz to 454.19375 MHz are used. It is assumed that no carrier sense is required, and the determination of the free state is induced in an antenna having an absolute gain of 2.14 dB. The voltage is 7 μV or less, the determination time is 200 ms or more, and the response time is within 20 ms. ”

  In the wireless communication system according to the above-described conventional example 1, it is not necessary to perform carrier sense by applying the proviso of the carrier sense rules. However, in other words, there is a problem that the transmission antenna power is regulated to 1 mW or less by the regulation of the carrier sense, and the transmission power is very small and the propagation distance is very short. In addition, as described above, the wireless communication system capable of simultaneous communication disclosed in Patent Documents 1 to 3 has the same basic configuration as that of Conventional Example 1, and has the same problems as in Conventional Example 1.

  In the wireless communication system according to the second conventional example, if the slave units 201 to 203 and the relay apparatuses 211 to 213 are configured to have a carrier sense function, a simultaneous communication wireless communication system that satisfies the above carrier sense regulations can be obtained. Can be configured. However, since the relay apparatuses 211 to 213 transmit three radio waves simultaneously, it is necessary to arrange the three relay apparatuses 211 to 213 apart from each other by a predetermined distance or more in order to avoid radio wave interference. Therefore, there is a problem that it is difficult to integrate the base unit 210 in a small size.

  The object of the present invention is to solve the above-mentioned problems, satisfy the above-mentioned carrier sense regulations, transmit at a transmission antenna power of 10 mW, and at the same time make the master unit small and integrated or unnecessary. It is an object of the present invention to provide a wireless communication apparatus capable of simultaneous phone calls and a wireless communication system using the same.

A radio communication apparatus according to a first aspect of the present invention is a radio communication apparatus for a simultaneous call radio communication system including a master unit that operates as a repeater and at least three slave units, and operates as the slave unit. A wireless communication device,
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a radio signal in a predetermined pair channel;
Sub-reception means for receiving a radio signal on a channel different from the pair channel is provided.

In the wireless communication apparatus according to the first aspect of the invention, the wireless communication apparatus is a radio equipment for a specific low power radio station radio telephone,
The transmission means can transmit a radio signal with an antenna power of 10 mW.

A radio communication apparatus according to a second invention is a radio communication apparatus for a simultaneous call radio communication system including a master unit that operates as a repeater and at least three slave units, and operates as the master unit. A wireless communication device,
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a radio signal in a predetermined pair channel;
At least three sub-reception means for receiving radio signals on one of the at least three channels different from the paired channels,
Audio mixing means for demodulating each radio signal received by each sub-receiving means and adding and mixing the demodulated audio signals, and outputting the added and mixed audio signals to the transmitting means Features.

In the wireless communication device according to the second invention, the wireless communication device is a radio equipment for a specific low-power radio station radio telephone,
The transmission means can transmit a radio signal with an antenna power of 10 mW.

A wireless communication system according to a third invention is
It comprises at least three wireless communication devices according to the first invention and a wireless communication device according to the second invention.

In the wireless communication system according to the third invention,
The reception channel of each sub-reception unit of the wireless communication device according to the second invention is a transmission channel of the transmission unit of at least three wireless communication devices according to the first invention,
The transmission channel of the transmission means of the wireless communication device according to the second invention is a reception channel of the sub reception means of at least three wireless communication devices according to the first invention.

A wireless communication device according to a fourth aspect of the present invention is a wireless communication device for a simultaneous call wireless communication system including a first slave unit that operates as a repeater and at least two second slave units, A wireless communication device that operates as the second slave unit,
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a radio signal in a predetermined pair channel;
Sub-reception means for receiving a radio signal on a channel different from the pair channel is provided.

In the wireless communication apparatus according to the fourth aspect of the invention, the wireless communication apparatus is a radio equipment for a specific low power radio station radio telephone,
The transmission means can transmit a radio signal with an antenna power of 10 mW.

A wireless communication device according to a fifth aspect of the present invention is a wireless communication device for a simultaneous call wireless communication system including a first slave unit that operates as a repeater and at least two second slave units, A wireless communication device that operates as the first slave unit,
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a radio signal in a predetermined pair channel;
At least one sub-receiving means for receiving a radio signal on a channel different from the pair channel;
The at least one sub-receiving unit and each audio signal demodulated by demodulating each radio signal received by the receiving unit and the audio signal from the first slave unit are added and mixed, and then added and mixed Voice mixing means for outputting a later voice signal to the transmission means.

In the wireless communication apparatus according to the fifth aspect,
The radio communication device is a radio equipment for a specific low power radio station radio telephone,
The transmission means can transmit a radio signal with an antenna power of 10 mW.

A wireless communication system according to a sixth invention is:
The wireless communication apparatus according to the fourth invention and the wireless communication apparatus according to the fifth invention are provided.

In the radio communication system according to the sixth invention,
The reception channel of the reception means of the wireless communication device according to the fifth invention is a transmission channel of the transmission means of one wireless communication device of at least two wireless communication devices according to the fourth invention,
The reception channel of the sub-reception means of the wireless communication device according to the fifth invention is a transmission channel of the transmission means of another one of the at least two wireless communication devices according to the fourth invention. And
The transmission channel of the transmission means of the wireless communication device according to the fifth invention is a reception channel of the reception means of one wireless communication device of at least two wireless communication devices according to the fourth invention, and the above It is a reception channel of the sub-reception means of another one of the at least two wireless communication devices according to the fourth invention.

  Therefore, according to the wireless communication device and the wireless communication system using the same according to the present invention, the carrier sense can be satisfied and transmission can be performed with a transmission antenna power of 10 mW, and the master unit can be integrated in a small size or It can be unnecessary.

It is a block diagram which shows the structural example of the radio | wireless communications system concerning the prior art example 1. FIG. It is a block diagram which shows the structural example of the radio | wireless communications system concerning the prior art example 2. FIG. 1 is a block diagram illustrating a configuration example of a wireless communication system according to a first embodiment. FIG. 4 is a block diagram illustrating a configuration example of a parent device 20 in FIG. 3. It is a block diagram which shows the structural example of the subunit | mobile_unit 10 of FIG. It is a flowchart which shows the 1st part of the communication control process performed by the main | base station 20 of FIG. It is a flowchart which shows the 2nd part of the communication control process performed by the main | base station 20 of FIG. It is a flowchart which shows the 3rd part of the communication control process performed by the main | base station 20 of FIG. It is a flowchart which shows the communication control process performed by the subunit | mobile_unit 10-1 of FIG. It is a flowchart which shows the communication control process performed by the subunit | mobile_unit 10-2 of FIG. It is a flowchart which shows the communication control process performed by the subunit | mobile_unit 10-3 of FIG. It is a block diagram which shows the example of a structure of the radio | wireless communications system concerning Embodiment 2, Comprising: It is a block diagram which shows the operation | movement during the simultaneous call of the subunit | mobile_unit 10-1 and the subunit | mobile_unit 10-2. It is a block diagram which shows the structural example of the radio | wireless communications system concerning Embodiment 2, Comprising: It is a block diagram which shows the operation | movement after the response from the subunit | mobile_unit 10-3 after the operation | movement of FIG. 8A. It is a flowchart which shows the communication control process performed by the subunit | mobile_unit 10-1 of FIG. 8A and 8B. It is a flowchart which shows the communication control process performed by the subunit | mobile_unit 10-2 of FIG. 8A and 8B. It is a flowchart which shows the communication control process performed by the subunit | mobile_unit 10-3 of FIG. 8A and 8B.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In addition, in each following embodiment, the same code | symbol is attached | subjected about the same component.

Embodiment 1. FIG.
FIG. 3 is a block diagram illustrating a configuration example of the wireless communication system according to the first embodiment. 3, the wireless communication system according to the first embodiment includes, for example, three slave units 10-1 to 10-3 (generically, denoted by reference numeral 10) and a master unit 20 that is a relay unit. Configured. In FIG. 3, the portion surrounded by a double line indicates the main transmission / reception unit. Also, channel numbers CH0 to CH3 in FIG. 3 are any different channel numbers selected from, for example, channel numbers 1 to 18 in Table 3.2 on page 5 of Non-Patent Document 1. In this embodiment, the channel of the main transmission / reception unit is a transmission / reception channel used in the duplex method for simultaneous calls, and uses a pair of waves having the same channel number (hereinafter referred to as a pair channel).

  In FIG. 3, the subunit | mobile_unit 10-1 is provided with the one 10 mW modulation transmission part 13 and the two reception demodulation parts 11-1 and 11-2, and the modulation transmission part 13 and the reception demodulation part 11-1 are as follows. The reception demodulation unit 11-2 is a sub-reception unit that uses a channel different from that of the reception demodulation unit 11-1. The subunit | mobile_unit 10-2 is provided with the one 10 mW modulation transmission part 13 and the two reception demodulation parts 11-1 and 11-2, and the modulation transmission part 13 and the reception demodulation part 11-1 use a pair channel. The reception demodulation unit 11-2 is a sub-reception unit that uses a channel different from that of the reception demodulation unit 11-1. The subunit | mobile_unit 10-3 is provided with the one 10 mW modulation transmission part 13 and the two reception demodulation parts 11-1 and 11-2, and the modulation transmission part 13 and the reception demodulation part 11-1 use a pair channel. The reception demodulation unit 11-2 is a sub-reception unit that uses a channel different from that of the reception demodulation unit 11-1. Here, the main transmission / reception units of the slave units 10-1 to 10-3 use different pair channels.

  Base unit 20 includes one 10 mW modulation transmission unit 23, four reception demodulation units 21-1 to 21-4, and audio mixing unit 22. The modulation transmission unit 23 and the reception demodulation unit 21-4 transmit and receive using a pair channel having a transmission channel corresponding to the reception channel of the sub reception unit of each of the slave units 10-1 to 10-3, and the other reception demodulation units 21 -1 to 21-3 are sub-reception units that use different channels that are reception channels corresponding to the transmission channels of the main reception units of the slave units 10-1 to 10-3.

  In the wireless communication system of FIG. 3, the reception channels of reception demodulation units 21-1 to 21-3 that are sub-reception units of base unit 20 are modulation transmission units that are transmission units of slave units 10-1 to 10-3. The transmission channel of the modulation transmission unit 23 which is 13 transmission channels and is a transmission means of the parent device 20 is a reception channel of 11-2 which is a sub reception means of the child devices 10-1 to 10-3.

  In the wireless communication system configured as described above, the reception demodulation unit 21-4 of the parent device 20 and the reception demodulation units 11-1 of the child devices 10-1 to 10-3 repeat carrier sense at a predetermined cycle. No audio signal is output because there is no other station to transmit on the channel. The modulation transmission unit 13 of each of the slave units 10-1 to 10-3 modulates the radio signal according to the voice signal of the voice input to each microphone 14 through a different channel, and the reception demodulation unit 21-1 of the master unit 20 respectively. To 21-3. On the other hand, the three audio signals demodulated by the reception demodulation units 21-1 to 21-3 of the base unit 20 are added and mixed by the audio mixing unit 22, and then output to the modulation transmission unit 23 to be output to each slave unit 10- It is transmitted to the reception demodulation unit 11-2 which is each of the sub-reception units 1 to 10-3. The reception demodulation unit 11-2, which is each sub-reception unit 10-1 to 10-3 of each slave unit, demodulates the received radio signal into an audio signal, and then outputs it to each speaker 16. Thereby, the operator of each subunit | mobile_unit 10-1 to 10-3 can hear the voice of the operator of all the subunit | mobile_unit 10-1 to 10-3, and can implement | achieve three-party simultaneous call.

  Accordingly, since the parent device 20 and each of the child devices 10-1 to 10-3 perform carrier sense, the carrier sense can be satisfied and transmitted with a transmission antenna power of 10 mW, and transmitted with a transmission antenna power of 10 mW. The propagation distance can be increased compared to the time of transmission, and the area where transmission and reception can be performed can be greatly expanded. Moreover, since there is only one modulation transmission unit 23 of the base unit 20, it can be integrated in a small size. Hereinafter, the detailed configuration and detailed operation of the master unit 20 and the slave units 10-1 to 10-3 will be described.

  FIG. 4 is a block diagram showing a configuration example of the base unit 20 of FIG. In FIG. 4, base unit 20 includes reception antenna 21 </ b> A, four reception demodulation units 21-1 to 21-4, audio mixing unit 22, modulation transmission unit 23, transmission antenna 23 </ b> A, and control unit 25. It is configured with.

  In FIG. 4, each of the reception demodulation units 21-1 to 21-4 receives the radio signal received by the reception antenna 21 </ b> A, demodulates the audio signal, and outputs it to the audio mixing unit 22. The audio mixing unit 22 adds and mixes a plurality of input audio signals, and then outputs the added audio signal to the modulation transmission unit 23. The modulation transmission unit 23 modulates the radio signal according to the input audio signal, and then transmits the modulated radio signal from the transmission antenna 23A. The control unit 25 controls the operation of the parent device 20 by executing the communication control process of FIGS. 6A to 6C. Here, the control unit 25 controls the carrier sensing operation and the reception frequency of the reception demodulation units 21-1 to 21-4, and receives the carrier sense results from the reception demodulation units 21-1 to 21-4. The control unit 25 controls the transmission frequency of the modulation transmission unit 23.

  In the configuration example of FIG. 4, the reception antenna 21 </ b> A and the transmission antenna 23 </ b> A may be configured with one antenna device via a duplexer (not shown).

  FIG. 5 is a block diagram showing a configuration example of the slave unit 10 of FIG. In FIG. 5, the slave 10 includes a reception antenna 11A, two reception demodulation units 11-1 to 11-2, an audio mixing unit 12, a modulation transmission unit 13, a transmission antenna 13A, a microphone 14, A control unit 15, a speaker 16, and an operation unit 17 having a PTT (Push To Talk) key 18 are provided.

  In FIG. 5, the control part 15 controls operation | movement of the subunit | mobile_unit 10-1 to 10-3 by performing the communication control process of FIG. 7A-FIG. 7C. Here, the control unit 15 controls the operation and the reception frequency of the carrier sense and the like of the reception demodulation units 11-1 to 11-2, and receives the carrier sense result from the reception demodulation units 11-1 to 11-2. The control unit 15 controls the transmission frequency of the modulation transmission unit 13. Each of the reception demodulation units 11-1 to 11-2 receives the radio signal received by the reception antenna 11 </ b> A, demodulates the audio signal, and outputs it to the audio mixing unit 12. The audio mixing unit 12 adds and mixes a plurality of input audio signals, and then outputs the added and mixed audio signal to the speaker 16 to convert it into audio and output it. When the operator of the slave unit 10 turns on the PTT key 18 of the operation unit 17, the control unit 15 turns on the operation of the modulation transmission unit 13. At this time, the modulation transmission unit 13 starts from the sound input to the microphone 14. After modulating the radio signal in accordance with the converted audio signal, the modulated radio signal is transmitted from the transmission antenna 13A.

  In the configuration example of FIG. 5, the reception antenna 11 </ b> A and the transmission antenna 13 </ b> A may be configured by a single antenna device via a duplexer (not shown).

  6A to 6C are flowcharts showing communication control processing executed by the base unit 20 of FIG.

  In step S101 of FIG. 6A, after waiting for reception of a radio signal on channels 0 to 3 in the 440 MHz band, the processing after step S111 in FIG. 6A, the processing after step S211 in FIG. 6B, and the processing after step S311 in FIG. The processing is executed simultaneously by, for example, multiprocessing.

  In step S111 of FIG. 6A, it is determined whether or not a radio signal is received on channel 1 in the 440 MHz band. If YES, the process proceeds to step S112. If NO, the process returns to the end of step S101. In step S112, it is determined whether a radio signal is being transmitted on channel 0 of the 421 MHz band. If YES, the process proceeds to step S113, and if NO, the process proceeds to step S114. In step S113, the audio signal obtained by demodulating the radio signal received on channel 1 in the 440 MHz band is added to the audio signal of the radio signal transmitted on channel 0 in the 421 MHz band, and the process returns to the end of step S101.

  In step S114, carrier sense is performed on channel 0 in the 440 MHz band. In step S115, it is determined whether or not there is a carrier in channel 0 in the 440 MHz band. If YES, the process proceeds to step S116. If NO, the process proceeds to step S119. move on. In step S116, carrier sense is performed on channel 0 in the 440 MHz band, and in step S117, it is determined whether or not there is a carrier in all channels 1 to 3 in the 440 MHz band. If YES, the process proceeds to step S118. Returns to step S115. In step S118, the relay operation is stopped and the communication control process is terminated.

  In step S119, a voice signal obtained by demodulating a radio signal received on channel 1 in the 440 MHz band is modulated by a radio signal on channel 0 in the 421 MHz band and transmitted, thereby starting a simultaneous call of two or more parties. In S120, it is determined whether or not there is a carrier in all of the channels 1 to 4 in the 440 MHz band. If YES, the process proceeds to step S121. If NO, the process returns to step S120. In step S121, transmission of the radio signal of channel 421 in the 421 MHz band is stopped and the communication control process is terminated.

  In step S211 in FIG. 6B, it is determined whether or not a radio signal is received on channel 2 in the 440 MHz band. If YES, the process proceeds to step S212. If NO, the process returns to the end of step S101 in FIG. 6A. In step S212, it is determined whether a radio signal is being transmitted on channel 0 of the 421 MHz band. If YES, the process proceeds to step S213, and if NO, the process proceeds to step S214. In step S213, the audio signal obtained by demodulating the radio signal received on channel 2 in the 440 MHz band is added to the audio signal of the radio signal transmitted on channel 0 in the 421 MHz band, and then the process returns to the end of step S101 in FIG. 6A.

  In step S214, carrier sense is performed on channel 0 in the 440 MHz band, and in step S215, it is determined whether there is a carrier on channel 0 in the 440 MHz band. If YES, the process proceeds to step S216. If NO, the process proceeds to step S219. move on. In step S216, carrier sense is performed on channel 0 in the 440 MHz band, and in step S217, it is determined whether or not there is a carrier in all channels 1 to 3 in the 440 MHz band. If YES, the process proceeds to step S218. If NO, Returns to step S215. After stopping the relay operation in step S218, the communication control process ends.

  In step S219, a voice signal obtained by demodulating a radio signal received on channel 2 in the 440 MHz band is modulated with a radio signal on channel 0 in the 421 MHz band and transmitted, thereby starting simultaneous conversation of two or more parties. In S220, it is determined whether or not there are no carriers in all channels 1 to 4 in the 440 MHz band. If YES, the process proceeds to step S221. If NO, the process returns to step S220. In step S221, the transmission of the wireless signal of channel 421 in the 421 MHz band is stopped and the communication control process is terminated.

  In step S311 in FIG. 6C, it is determined whether or not a radio signal is received on channel 3 in the 440 MHz band. If YES, the process proceeds to step S312. If NO, the process returns to the end of step S101 in FIG. 6A. In step S312, it is determined whether a radio signal is being transmitted on channel 0 in the 421 MHz band. If YES, the process proceeds to step S313, and if NO, the process proceeds to step S314. In step S313, the audio signal obtained by demodulating the radio signal received on channel 3 in the 440 MHz band is added to the audio signal of the radio signal transmitted on channel 0 in the 421 MHz band, and then the process returns to the end of step S101 in FIG. 6A.

  In step S314, carrier sensing is performed on channel 0 in the 440 MHz band, and in step S315, it is determined whether there is a carrier in channel 0 in the 440 MHz band. If YES, the process proceeds to step S316. If NO, the process proceeds to step S319. move on. In step S316, carrier sense is performed on channel 0 in the 440 MHz band, and in step S317, it is determined whether or not there is a carrier in all channels 1 to 3 in the 440 MHz band. If YES, the process proceeds to step S318, and if NO Returns to step S315. After stopping the relay operation in step S318, the communication control process is terminated.

  In step S319, a voice signal obtained by demodulating the radio signal received by the channel 3 of the 440 MHz band is modulated by the radio signal of the channel 0 of the 421 MHz band and transmitted, thereby starting simultaneous conversation of two or more parties. In S320, it is determined whether or not there is a carrier in all of the channels 1 to 4 in the 440 MHz band. If YES, the process proceeds to step S321. If NO, the process returns to step S320. In step S321, the transmission of the wireless signal of channel 421 in the 421 MHz band is stopped, and then the communication control process ends.

  FIG. 7A is a flowchart showing communication control processing executed by handset 10-1 of FIG.

  In step S401 of FIG. 7A, reception of a radio signal is awaited on channels 0 and 1 in the 421 MHz band, and in step S402, it is determined whether a radio signal is received on channel 0 in the 421 MHz band. If YES, the process proceeds to step S403. On the other hand, if NO, the process proceeds to step S404. In step S403, an audio signal obtained by demodulating the radio signal received on channel 0 in the 421 MHz band is output to the speaker 16 to be sounded. In step S404, it is determined whether the PTT key 18 is turned on. If YES, step S405 is performed. On the other hand, if NO, the process returns to step S402.

  In step S405, carrier sense is performed on channel 1 in the 421 MHz band. In step S406, it is determined whether or not there is a carrier in channel 1 in the 421 MHz band. If YES, the process proceeds to step S407. If NO, the process proceeds to step S409. move on. In step S407, carrier sense is performed on channel 1 in the 421 MHz band. In step S408, it is determined whether or not the PTT key 18 is turned off. If YES, the communication control process is terminated. If NO, the process proceeds to step S406. Return.

  In step S409, two or more simultaneous calls are started by starting to transmit a radio signal modulated in accordance with the voice signal of the voice input to the microphone 14 on the channel 1 of the 440 MHz band. In step S410, the PTT key 18 Whether or not is turned off is determined. If YES, the process proceeds to step S411. If NO, the process returns to step S410. In step S411, after stopping the transmission of the radio signal on the channel 1 in the 440 MHz band, the communication control process is terminated.

  FIG. 7B is a flowchart showing communication control processing executed by the slave unit 10-2 of FIG.

  In step S501 of FIG. 7B, reception of a radio signal is awaited on channels 0 and 2 in the 421 MHz band, and in step S502, it is determined whether a radio signal is received on channel 0 in the 421 MHz band. If YES, the process proceeds to step S503. On the other hand, if NO, the process proceeds to step S504. In step S503, an audio signal obtained by demodulating the radio signal received on channel 0 in the 421 MHz band is output to the speaker 16 to be sounded. In step S504, it is determined whether the PTT key 18 is turned on. If YES, step S505 is performed. On the other hand, if NO, the process returns to step S502.

  In step S505, carrier sense is performed on channel 2 in the 421 MHz band, and in step S506, it is determined whether there is a carrier in channel 2 in the 421 MHz band. If YES, the process proceeds to step S507. If NO, the process proceeds to step S509. move on. In step S507, carrier sense is performed on channel 2 in the 421 MHz band, and in step S508, it is determined whether or not the PTT key 18 is turned off. If YES, the communication control process ends. If NO, the process proceeds to step S506. Return.

  In step S509, two or more simultaneous calls are started by starting to transmit a radio signal modulated in accordance with the voice signal of the voice input to the microphone 14 on the channel 2 of the 440 MHz band. In step S510, the PTT key 18 Is determined. If YES, the process proceeds to step S511. If NO, the process returns to step S510. In step S511, after stopping the transmission of the radio signal on the channel 2 in the 440 MHz band, the communication control process is terminated.

  FIG. 7C is a flowchart showing communication control processing executed by the slave unit 10-3 of FIG.

  In step S601 of FIG. 7C, reception of a radio signal is awaited on channels 0 and 3 in the 421 MHz band, and in step S602, it is determined whether or not a radio signal is received on channel 0 in the 421 MHz band. If YES, the process proceeds to step S603. On the other hand, if NO, the process proceeds to step S604. In step S603, an audio signal obtained by demodulating the radio signal received on channel 0 in the 421 MHz band is output to the speaker 16 to be sounded. In step S604, it is determined whether the PTT key 18 is turned on. If YES, step S605 is performed. On the other hand, if NO, the process returns to step S602.

  In step S605, carrier sense is performed on channel 3 in the 421 MHz band. In step S606, it is determined whether or not there is a carrier in channel 3 in the 421 MHz band. If YES, the process proceeds to step S607. If NO, the process proceeds to step S609. move on. In step S607, carrier sense is performed on channel 3 of the 421 MHz band, and in step S608, it is determined whether or not the PTT key 18 is turned off. If YES, the communication control process ends. If NO, the process proceeds to step S606. Return.

  In step S609, two or more simultaneous calls are started by starting to transmit a radio signal modulated in accordance with the voice signal of the voice input to the microphone 14 on the channel 3 of the 440 MHz band. In step S610, the PTT key 18 Whether or not is turned off is determined. If YES, the process proceeds to step S611. If NO, the process returns to step S610. In step S611, after stopping the transmission of the radio signal in the channel 3 of the 440 MHz band, the communication control process is terminated.

  As described above, according to the present embodiment, the operators of the slave units 10-1 to 10-3 can hear the voices of the operators of all the slave units 10-1 to 10-3. Simultaneous call. Moreover, since the main | base station 20 and each subunit | mobile_unit 10-1 to 10-3 each perform a carrier sense, the said carrier sense prescription | regulation is satisfy | filled and it can transmit with the transmission antenna power 10mW, and it transmits with the transmission antenna power 10mW The propagation distance can be increased compared to the time of transmission, and the area where transmission and reception can be performed can be greatly expanded. Moreover, since there is only one modulation transmission unit 23 of the base unit 20, it can be integrated in a small size.

  In the first embodiment described above, it is possible to realize a wireless communication system for simultaneous four-party calls by adding another slave unit 10 and adding a reception demodulation unit 21 in the master unit 20. Similarly, it is possible to realize a wireless communication system for simultaneous communication of five or more persons.

Embodiment 2. FIG.
FIG. 8A is a block diagram illustrating a configuration example of the wireless communication system according to the second embodiment, and is a block diagram illustrating an operation during simultaneous calls between the slave unit 10-1 and the slave unit 10-2. FIG. 8B is a block diagram illustrating a configuration example of the wireless communication system according to the second embodiment, and is a block diagram illustrating an operation after a response from the slave unit 10-3 after the operation of FIG. 8A. Here, each of the slave units 10-1 to 10-3 has the same device configuration as that of FIG. 5 of Embodiment 1 except that it further includes an audio mixing unit 12A. It has a communication control processing function.

  The audio mixing unit 12A and its peripheral circuits in FIGS. 8A and 8B will be described in advance. The audio mixing unit 12 adds and mixes the audio signals from the reception demodulation units 11-1 and 11-2, and then outputs them to the speaker 16 and the audio mixing unit 12A. The sound mixing unit 12 </ b> A adds and mixes the sound signal from the sound mixing unit 12 and the sound signal from the microphone 14, and then outputs the mixed signal to the modulation transmission unit 13. When the speaker 16 is configured by an audio output device such as an earphone or a headphone that does not generate howling, the audio signal from the microphone 14 is input to the audio mixing unit 12 and the audio signal from the audio mixing unit 12 is output as the audio output. You may output to an apparatus and the modulation | alteration transmission part 13. FIG. In this case, the audio mixing unit 12A can be omitted.

  In FIG. 8A, handset 10-1 operates as a repeater and includes one 10mW modulation transmission unit 13 and two reception demodulation units 11-1 and 11-2. The unit 11-1 transmits and receives using a pair channel, and the reception demodulation unit 11-2 is a sub reception unit that uses a channel different from that of the reception demodulation unit 11-1. The subunit | mobile_unit 10-2 is provided with the one 10mW modulation transmission part 13 and the one reception demodulation part 11-1, and the modulation | alteration transmission part 13 and the reception demodulation part 11-1 which are main transmission / reception parts are the subunit | mobile_unit 10. -1 is transmitted / received to / from slave unit 10-1 using a pair channel corresponding to the pair channel -1. As a result, the main transmission / reception units of the slave units 10-1 and 10-2 are simultaneously talking using the microphone 14 and the speaker 16.

  In addition, the subunit | mobile_unit 10-3 which participates in a simultaneous call later is provided with one 10mW modulation transmission part 13 and two reception demodulation parts 11-1, 11-2, and the modulation transmission part 13 and reception demodulation The unit 11-1 is set to be able to transmit and receive using a pair channel corresponding to the reception channel of the sub reception unit of the slave unit 10-1, and the reception demodulation unit 11-2 is a channel different from the reception demodulation unit 11-1. This is a sub-reception unit that uses a channel corresponding to the pair channel of the main transmission / reception unit of the slave unit 10-1. Here, the reception demodulator 11-1 of the slave unit 10-3 can perform carrier sense, but there is no other station to transmit.

  Next, in FIG. 8B, the operation when there is a response from the child device 10-3 after the operation of FIG. 8A will be described below.

  In FIG. 8B, when the modulation transmission unit 13 of the slave unit 10-3 transmits a radio signal through the transmission channel of the main transmission / reception unit according to the voice signal converted from the voice input to the microphone 14, the reception of the slave unit 10-1 The demodulating unit 11-2 receives the radio signal, demodulates the audio signal, adds and mixes the demodulated audio signal with the audio signal from the reception demodulating unit 11-1 and the audio mixing unit 12, and then performs the addition and mixing. The audio signal is output to the speaker 16 and the audio mixing unit 12A. At this time, the operator of the slave unit 10-1 can hear the voice of the operator of the slave units 10-2 and 10-3.

  The sound mixing unit 12 </ b> A adds and mixes the sound signal from the sound mixing unit 12 and the sound signal from the microphone 14, and then outputs the mixed signal to the modulation transmission unit 13. Modulation transmitter 13 modulates a radio signal according to the input audio signal and transmits it to slave units 10-2 and 10-3 through the channel of the main transmitter / receiver. As a result, the reception demodulation unit 11-1 of the child device 10-2 and the reception demodulation unit 11-2 of the child device 10-3 demodulate the received radio signal, so that the child devices 10-2 and 10-3 The operator can hear the voices of all the slave units 10-1 to 10-3 that participate, and can realize a three-party simultaneous call.

  8A and 8B, the reception channel of the reception demodulation unit 11-1 that is the reception unit of the slave unit 10-1 is the transmission channel of the modulation transmission unit 13 that is the transmission unit of the slave unit 10-2. Yes, the reception channel of the reception demodulator 11-2 which is the sub-reception unit of the slave unit 10-1 is the transmission channel of the modulation transmission unit 13 which is the transmission unit of the slave unit 10-3. The transmission channel of the modulation transmission unit 13 which is a transmission unit includes the reception channel of the reception demodulation unit 11-1 which is a reception unit of the slave unit 10-2 and the reception demodulation unit 11 which is a sub reception unit of the slave unit 10-3. -2 reception channel.

  In the wireless communication system configured as described above, a three-party simultaneous call can be realized as described above. Moreover, each receiving demodulation part 11-1 of the subunit | mobile_unit 10-1 to 10-3 repeats a carrier sense with a predetermined period. In the operation example of FIG. 8A, the slave units 10-1 and 10-2 start simultaneous communication with each other after the carrier sense, and the slave unit 10-3 is a reception demodulation unit 11-1 which is a main reception unit. Is used to perform carrier sense, but no audio signal is output because there is no other station to receive.

  Next, communication control processing executed by the slave units 10-1 to 10-3 in FIGS. 8A and 8B will be described below.

  FIG. 9A is a flowchart showing a communication control process executed by the slave unit 10-1 of FIGS. 8A and 8B.

  In step S701 of FIG. 9A, the PTT key 18 is turned on, a radio signal modulated in accordance with the audio signal is transmitted on the channel 1 of the 421 MHz band, the radio signal is received on the channel 1 of the 440 MHz band, and the audio signal is demodulated and output. As a result, a call is being made simultaneously with the slave unit 10-2, and reception of a radio signal is awaited on the channel 2 in the 440 MHz band. Next, in step S702, it is determined whether or not the PTT key 18 is turned off. If YES, the process proceeds to step S706, and if NO, the process proceeds to step S703. In step S703, it is determined whether or not a radio signal is transmitted through channel 2 in the 440 MHz band. If YES, the process proceeds to step S704. If NO, the process returns to step S702.

  Next, in step S704, each audio signal obtained by demodulating each radio signal received on channels 1 and 2 of the 440 MHz band is added to the audio signal of the radio signal transmitted on channel 1 in the 421 MHz band, and the PTT key 18 is turned off in step S705. If YES, the process proceeds to step S706. If NO, the process returns to step S705. In step S706, the wireless signal transmission on the channel 421 in the 421 MHz band is stopped, and then the communication control process ends.

  FIG. 9B is a flowchart showing a communication control process executed by the slave unit 10-2 of FIGS. 8A and 8B.

  In step S801 in FIG. 9B, a radio signal modulated in accordance with the audio signal is transmitted on channel 1 in the 440 MHz band, and the radio signal is received on channel 1 in the 421 MHz band, and the audio signal is demodulated and output. Is in a call at the same time. Next, in step S802, it is determined whether or not the PTT key 18 is turned off. If YES, the process proceeds to step S803, and if NO, the process returns to step S802. In step S803, after stopping the transmission of the radio signal in the channel 1 of the 440 MHz band, the communication control process is terminated.

  FIG. 9C is a flowchart showing communication control processing executed by the slave unit 10-3 of FIGS. 8A and 8B.

  In step S901 of FIG. 9C, a radio signal is received by channel 1 in the 421 MHz band, the audio signal is demodulated and output, and reception of the radio signal is awaited by channel 2 in the 421 MHz band. Next, in step S902, it is determined whether or not the PTT key 18 is turned on. If YES, the process proceeds to step S903, and if NO, the process returns to step S902. In step S903, carrier sense is performed on channel 2 in the 421 MHz band. In step S904, it is determined whether or not there is a carrier in channel 2 in the 421 MHz band. If YES, the process proceeds to step S905. If NO, the process proceeds to step S907. move on. In step S905, carrier sense is performed on channel 2 of the 421 MHz band, and in step S906, it is determined whether or not the PTT key 18 is turned off. If YES, the communication control process ends. If NO, the process proceeds to step S904. Return. In step S907, a three-party simultaneous call is started by starting to transmit a radio signal modulated in accordance with the audio signal of the voice input to the microphone 14 on the channel 2 in the 440 MHz band. In step S908, the PTT key 18 is turned off. If YES, the process proceeds to step S909. If NO, the process returns to step S908. In step S909, the wireless signal transmission on the channel 2 in the 440 MHz band is stopped, and then the communication control process is terminated.

  Although the communication control processing of FIGS. 9A to 9C is described as the processing of the slave units 10-1 to 10-3 for convenience, the three slave units 10-1 to 10-3 realize a three-party simultaneous call function. In order to do this, each of the slave units 10-1 to 10-3 has the hardware configuration of the slave unit 10-1, holds the communication control processing program of FIG. 9A to FIG. In response, one of the three programs is executed. In other words, the first two slave units that simultaneously talk simultaneously execute the communication control process of FIGS. 9A and 9B, and the slave units that subsequently participate execute the communication control process of FIG. 9C.

  In the wireless communication system configured as described above, a three-party simultaneous call can be realized as described above. Moreover, since each receiving demodulation part 11-1 of the subunit | mobile_unit 10-1 to 10-3 performs carrier sense, it can be transmitted with the transmission antenna power 10mW, satisfy | filling the prescription | regulation of the said carrier sense, and transmission antenna power 10mW The transmission distance can be made longer than when transmitting by, and the area that can be transmitted and received can be greatly expanded. In addition, the base unit 20 is unnecessary, and the configuration of the wireless communication system can be greatly simplified as compared with the conventional examples 1 and 2.

  The difference between the child device 10-2 and the child device 10-3 in FIG. 8A and FIG. 8B is that the child device 10-2 does not include the reception demodulation unit 11-2 as a sub reception unit. However, the present invention is not limited to this, and the slave unit 10-2 may include the reception demodulation unit 11-2. In this case, the slave unit 10-2 and the slave unit 10-3 are the same except for the used channel. It becomes the composition of.

In the second embodiment, a wireless communication system capable of simultaneous three-party communication is described. However, in order to realize four-party simultaneous communication, a reception demodulator 11- serving as a sub-reception unit in slave unit 10-1. 3 and the audio signal is output to the audio mixing unit 12, and the slave unit 10-4 to be added may have the following configuration.
(1) For example, a 10 mW modulation transmission unit 13 that transmits a radio signal through a channel 3 in a 440 MHz band;
(2) For example, a reception demodulator 11-1 that receives and senses a radio signal with channel 3 in the 421 MHz band (the modulation transmitter 13 and the reception demodulator 11-1 constitute a main transmitter / receiver, and a reception demodulator 11-1 is a carrier sense but there is no other station); and (3) a reception demodulator 11-2 that receives a radio signal on channel 1 of the 421 MHz band, for example.
Similarly, it is possible to realize a wireless communication system for simultaneous communication of five or more parties.

  In the above embodiment, the speaker 16 is used. However, the present invention is not limited to this, and an audio output device such as an earphone or a headphone may be used.

  In the above embodiment, the master unit 20 and the slave unit 10 are radio equipment for a specific low power radio station radio telephone, and the modulation transmitters 13 and 23 can transmit radio signals with an antenna power of 10 mW.

Summary of Embodiment In the first embodiment, each of the slave units 10-1 to 10-3 performs carrier sense on different channels using the reception demodulation unit 11-1 of the main transmission / reception unit, and performs modulation transmission of the main transmission / reception unit. The base unit 20 transmits radio signals including audio signals to the base unit 20 using the unit 13, while the base unit 20 receives the radio signals from the slave units 10-1 to 10-3 and demodulates the audio signals. After that, addition mixing is performed, the radio signal is returned according to the audio signal after addition mixing, and transmitted to each of the slave units 10-1 to 10-3 using the modulation transmission unit 23 of its own main transmission / reception unit on another channel. It is characterized by that.

  On the other hand, in the second embodiment, by providing the slave unit 10-1 with the function of the master unit 20, the pair of channels used by the master unit 20 is not used, and three or more parties are used. Realizes simultaneous calls. That is, Embodiments 1 and 2 are common in that simultaneous calls of three or more parties are realized using the main transmission / reception unit and the sub reception unit.

  As described above in detail, according to the wireless communication device and the wireless communication system using the wireless communication device according to the present invention, the carrier sense can be satisfied and transmission can be performed with a transmission antenna power of 10 mW. It can be small and integrated or unnecessary. Therefore, the wireless communication device and the wireless communication system using the wireless communication device according to the present invention satisfy the provisions as the wireless facility for the specific low power wireless station wireless telephone disclosed in Non-Patent Document 1, and are suitable as the wireless facility. is there.

10, 10-1 to 10-3 ... child machine,
11-1 to 11-2... Reception demodulation unit,
11A: receiving antenna,
12 ... Audio mixing unit,
13 Modulation transmitter,
13A: Transmitting antenna,
14 ... Microphone,
15 ... control unit,
16 ... Speaker,
17 ... operation part,
18 ... PTT key,
20 ... Master unit,
21-1 to 21-4... Reception demodulation unit,
21A: receiving antenna,
22 ... Audio mixing unit,
23. Modulation transmitter,
23A: Transmitting antenna,
25. Control unit,
101-103 ... cordless handset,
110 ... Master unit,
111 ... adder,
201-203 ... cordless handset,
210 ... Master unit,
211-213 ... Relay device,
214 ... adder,
215: Distributor.

Claims (10)

A wireless communication device for a simultaneous communication wireless communication system including a parent device that operates as a relay device and at least three child devices, the wireless communication device that operates as the parent device,
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a radio signal in a predetermined pair channel;
At least three sub-reception means for receiving radio signals on one of the at least three channels different from the paired channels,
Audio mixing means for demodulating each radio signal received by each sub-receiving means and adding and mixing the demodulated audio signals, and outputting the added and mixed audio signals to the transmitting means A wireless communication device. The radio communication device is a radio equipment for a specific low power radio station radio telephone,
2. The radio communication apparatus according to claim 1, wherein the transmission means is capable of transmitting a radio signal with an antenna power of 10 mW. A wireless communication system comprising: a first wireless communication device that is a wireless communication device according to claim 1 or 2 that operates as a master device; and at least three second wireless communication devices that operate as slave devices. ,
The second wireless communication device is
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a wireless signal to / from the first wireless communication device in a predetermined pair channel;
A wireless communication system, comprising: sub-receiving means for receiving a wireless signal on a channel different from the pair channel . The second radio communication device is a radio equipment for a specific low power radio station radio telephone,
4. The wireless communication system according to claim 3, wherein the transmission means of the second wireless communication apparatus is capable of transmitting a wireless signal with an antenna power of 10 mW. The receiving channel of each sub-receiving means of the first wireless communication device is a transmission channel of the transmission means 3 of the second radio communication device even without low,
Said transmission channel of the transmission means of the first wireless communication apparatus, according to claim 3 or 4, wherein the radio characterized in that it is a receiving channel of the three sub-receiving means of the second radio communication device even without least Communications system. A wireless communication apparatus for a simultaneous communication wireless communication system including a first slave unit operating as a relay unit and at least two second slave units, and wireless communication operating as the first slave unit A device,
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a radio signal in a predetermined pair channel;
At least one sub-receiving means for receiving a radio signal on a channel different from the pair channel;
The at least one sub-receiving unit and each audio signal demodulated by demodulating each radio signal received by the receiving unit and the audio signal from the first slave unit are added and mixed, and then added and mixed A radio communication apparatus comprising: audio mixing means for outputting a later audio signal to the transmission means. The radio communication device is a radio equipment for a specific low power radio station radio telephone,
7. The radio communication apparatus according to claim 6, wherein the transmission means is capable of transmitting a radio signal with an antenna power of 10 mW. A first wireless communication device that is a wireless communication device according to claim 6 or 7 that operates as a first child device, and at least two second wireless communication devices that operate as a second child device. A wireless communication system ,
The second wireless communication device is
Transmitting means and receiving means for performing carrier sense and transmitting / receiving a wireless signal to / from the first wireless communication device in a predetermined pair channel;
A wireless communication system, comprising: sub-receiving means for receiving a wireless signal on a channel different from the pair channel . The second radio communication device is a radio equipment for a specific low power radio station radio telephone,
9. The wireless communication system according to claim 8, wherein the transmission means of the second wireless communication apparatus is capable of transmitting a wireless signal with an antenna power of 10 mW. The receiving channel of the receiving means of the first wireless communication device is a single transmission channel of the transmission means of the second radio communication apparatus of the two of the second radio communication device even without low,
The receiving channel of the sub-receiving means of the first wireless communication device, the transmit channel of another one of the second transmission means of the wireless communication apparatus of the two of the second radio communication device even without least Yes,
Said transmission channel of the transmission means of the first wireless communication device, one receiving channel of the receiving means of the second radio communication apparatus of the two of the second radio communication device even without low, and no low both pieces of another one of the wireless communication system of claim 8, wherein it is a receiving channel of the second sub-receiving means of the wireless communication device of said second wireless communication device.

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