Transmitter receiver, repeater and radio communication system

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a transmission / reception device that performs mutual communication by a semi-duplex method using a predetermined pair of transmission / reception frequencies, a relay device that relays a transmission signal between a plurality of transmission / reception devices, and these transmission / reception devices and relays. It relates to a wireless communication system including a device.

【0002】

[Conventional technology]

As a wireless communication system configured to include a plurality of transmission / reception devices capable of mutual communication by this type of semi-duplex system, for example, a specific low power wireless communication system has been conventionally known. In this wireless communication system, mutual communication is possible by using a plurality of transmission / reception devices A to N and a repeater that relays transmission signals between transmission / reception devices A to N at a work site or the like. For example, transmission / reception In the devices A to N, the transmission frequency and the reception frequency are pre-assigned to fa and fb, respectively, and in the repeater, the transmission frequency and the reception frequency are pre-assigned to fb and fa, respectively. In such a configuration, for example, when the transmission / reception device B transmits to the transmission / reception device C, when the transmission / reception device B transmits at the transmission frequency fa, the repeater receives and demodulates the transmission frequency fa and modulates it with the demodulated signal. The transmission signal of the transmitted transmission frequency fb is transmitted. On the other hand, the transmission / reception device C receives the transmission signal from the transmission / reception device B by receiving the transmission signal of fb. On the contrary, when the transmission / reception device C responds to the transmission / reception device B, the transmission / reception device C can transmit the response signal to the transmission / reception device B via the repeater by transmitting at the transmission frequency of fa. In this case, the other transmitting / receiving devices A, D to N constantly receive the reception frequency of fb by the so-called carrier sense function, and transmission is prohibited when the reception level is equal to or higher than a predetermined level, thereby preventing interference. ing.

【0003】

[Problems to be Solved by the Invention]

However, this conventional wireless communication system has the following problems. That is, in this wireless communication system, when a pair of transmission / reception devices B and C are communicating, for example, an operator of the transmission / reception device A tries to perform emergency communication to other transmission / reception devices B to N. However, when both transmitting / receiving devices B and C are continuously communicating with each other, there is a problem that emergency communication cannot be performed unless the call between the two transmitting / receiving devices B and C is completed by the carrier sense function. .. In such a case, as a result of being unable to perform emergency contact communication, it may lead to personal injury. In addition, even if a failure occurs in a mass production manufacturing device in a mass production factory and a notification to that effect is made to other manufacturing personnel, emergency contact communication cannot be performed, which has a serious impact on production. Sometimes. Therefore, the conventional wireless communication system has a problem that it has a serious defect as a communication system.

【0004】

Further, in a transmission / reception device that communicates according to such a semi-duplex system, generally, the reception frequency of fb is always received, but the received sound is not emitted from the speaker. Therefore, it is possible to receive the emergency communication by removing the carrier sense function and adopting a configuration in which the received sound is constantly emitted from the speaker. However, in such a case, since the transmission frequency of the transmission / reception device A and the transmission frequency of the other transmission / reception device B (or C) being transmitted are the same, the beat is generated in the receiver of the transmission / reception devices C (or B) to N. Interference due to the phenomenon occurs. Therefore, it is practically impossible to perform emergency contact communication.

【0005】

The present invention has been made to solve such a problem, and provides a transmission / reception device capable of preferentially communicating emergency communication communication or the like even when another transmission / reception device is transmitting. Another purpose is to provide a relay device suitable for relaying a transmission signal between these transmission / reception devices, and a wireless communication system including these transmission / reception devices and the relay device. To do.

【0006】

[Means for solving problems]

The transmission / reception device according to claim 1 for achieving the above object is a transmission / reception device configured to be capable of transmission / reception by a semi-duplex system, and stops transmission when a predetermined signal is included in the received reception signal. It is characterized in that alarm control or transmission stop control for causing the signal is performed.

【0007】

In the normal state, this transmitter / receiver does not emit the received sound from the speaker according to the semi-duplex system during transmission. On the other hand, when a predetermined signal is included in the received received signal, an alarm control for warning the operator of the received transmitting / receiving device to stop or prohibit the transmission at both the time of transmission and the time of reception. To execute. In this case, the alarm can be displayed by the display device and the alarm sound can be emitted from the speaker. Further, when transmission is in progress, transmission stop control may be performed to automatically stop transmission. As a result, the operator who has transmitted a predetermined signal can reliably and preferentially perform emergency communication and the like without causing interference in other transmission / reception devices.

【0008】

The transmitting / receiving device according to claim 2 is a transmitting / receiving device configured to be capable of transmitting / receiving by a semi-duplex method, and is characterized in that when a predetermined voice message signal or alarm sound signal is received, the received sound is emitted from a speaker. To do.

【0009】

In this transmission / reception device, when a predetermined voice message signal or alarm sound signal is transmitted from another transmission / reception device, the received sound is emitted from the speaker. Therefore, the operator of the transmitted / received device that has emitted the sound can immediately understand that the emergency communication has been performed or that an abnormal state has occurred even during transmission. As a result, the transmission by the other transmission / reception device is stopped, and as a result, the operator who has transmitted the predetermined voice message signal or alarm sound signal can preferentially communicate the emergency contact communication or the like.

【0010】

The transmission / reception device according to claim 3 includes a storage unit that stores predetermined voice message data or alarm sound data in advance in the transmission / reception device according to claim 1, and includes a predetermined signal in the received signal. In addition, as an alarm control, it is characterized in that an alarm sound based on stored voice message data or alarm sound data is emitted from a speaker.

【0011】

By transmitting a predetermined voice message signal or alarm sound signal from the transmitting side, the voice message or alarm sound can be emitted to another transmitting / receiving device. On the other hand, in this transmission / reception device, by transmitting a predetermined signal such as an emergency signal, an alarm sound based on voice message data or alarm sound data stored in another transmission / reception device side is emitted. In this case, it is possible to emit a clear voice message or the like without obscuring the voice message or the alarm sound due to interference.

【0012】

The transmission / reception device according to claim 4 is characterized in that, in the transmission / reception device according to claim 2 or 3, the volume at the time of sound emission is controlled to be louder than the reception volume in the normal state.

【0013】

Even if a voice message is emitted in the event of an abnormality, the effect as an alarm for stopping transmission is diminished when the reception volume is reduced. In this transmission / reception device, a voice message or the like is emitted at a louder volume than in the normal state, so that the operator can more reliably understand that emergency communication is performed.

【0014】

The relay device according to claim 5 relays transmission signals between a plurality of transmission / reception devices configured to be capable of transmission / reception by a semi-duplex method, and also depending on the type of communication signal communicated from an external device via a communication line. It is characterized in that the transmission signal of the contents is transmitted to a plurality of transmission / reception devices. In this case, the external device may communicate the communication signal via either the wired communication line or the wireless communication line.

【0015】

For example, when a communication signal such as a device abnormality is communicated from an external device such as a mass-produced device, the relay device transmits a transmission signal having contents corresponding to the type of the communication signal to a plurality of transmission / reception devices. In this case, when transmission / reception is performed between the transmission / reception devices, the pair of transmission / reception devices performs alarm control and transmission stop control. Therefore, the operator during transmission can know that an abnormal state or an emergency has occurred, and by immediately stopping the transmission, the transmission signal from the relay device can be received without causing interference. Is possible.

【0016】

In this case, as the transmission signal having the content according to the type of the communication signal, not only the alarm control signal or the transmission stop control signal for stopping the transmission but also the voice message signal or the alarm sound signal may be transmitted.

【0017】

The wireless communication system according to claim 8 is characterized by including a plurality of transmission / reception devices according to any one of claims 1 to 4 and a relay device according to any one of claims 5 to 7. ..

【0018】

In this wireless communication system, when a pair of transmission / reception devices transmit / receive, transmission / reception between transmission / reception devices is performed by transmitting a voice message signal, an alarm sound signal, an alarm stop control signal, or a transmission stop control signal from the relay device. Can be stopped, and abnormalities of external devices can be transmitted to all transmitters and receivers.

【0019】

The wireless communication system according to claim 9 is configured to include a plurality of wireless communication systems according to claim 8, and a relay device in any one wireless communication system is an alarm control signal or transmission stop control for stopping transmission. It is characterized in that a signal is transmitted to each transmission / reception device in a plurality of wireless communication systems.

【0020】

In this wireless communication system, when an abnormality occurs in a specific external device, all the transmission / reception devices in a plurality of wireless communication systems can be simultaneously communicated.

【0021】

The wireless communication system according to claim 10 is the wireless communication system according to claim 8 or 9, wherein the relay device adds identification data for identifying the relay device or the external device at the time of transmission. ..

【0022】

In this wireless communication system, when an alarm control signal, a transmission stop control signal, or the like is transmitted from the relay device, identification data for identifying the relay device or the external device is given, so that the operator of the transmission / reception device can use the transmission / reception device. For example, it is possible to immediately identify an external device or the like in which an abnormality has occurred.

【0023】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the transmission / reception device, the relay device, and the wireless communication system according to the present invention will be described with reference to the accompanying drawings.

【0024】

First, the overall configuration of the wireless communication system will be described with reference to FIG. As shown in the figure, the wireless communication system 1 is configured by combining a plurality of communication systems 2a to 2n (hereinafter, also referred to as "communication system 2" when not distinguished). Since the communication systems 2a to 2n are the same in other configurations and functions except that the assigned transmission / reception frequencies are different from each other, the configurations and functions of the communication system 2a will be described below as a representative.

【0025】

The wireless communication system 2 is intended for communication between a plurality of workers who perform maintenance and inspection of a device 3 such as a printing machine, and is a plurality of slave units 4a corresponding to the transmission / reception device in the present invention. It is equipped with ~ 4n (hereinafter, also referred to as "slave unit 4" when not distinguished) and a relay device 6 that relays communication between slave units 4 and 4 and is connected to device 3 via a wired communication line 5. ing. Further, the relay device 6 includes an A repeater 11, an interface unit 12, and a B repeater 13, which correspond to the relay device in the present invention. Here, the interface unit 12 is for passing various signals, and a predetermined signal or all signals among the signals communicated from the device 3 or the B repeater 13 are transmitted to the communication line 14 Communicates with the interface unit 12 in another communication system 2 via. This enables simultaneous communication, which will be described later.

【0026】

The slave unit 4 is configured to be capable of transmission / reception by a frequency modulation method by a semi-duplex method with a pair of transmission / reception frequencies determined in advance. Specifically, the slave unit 4 is, for example, f in the 420 MHz to 430 MHz band._1a(In communication systems 2b to 2n, f_1b~ f_1n) And f_2a(In communication systems 2b to 2n, f_2b~ f_2n) Are the transmission frequency and reception frequency, respectively, and f as the transmission frequency for emergency communication._1aOther transmission frequencies different from f_3a(In communication systems 2b to 2n, f_3b~ f_3n) Can be sent. As a specific configuration, as shown in FIG. 2, the slave unit 4 includes an antenna 21, a microphone 22, a transmitter 23, a channel oscillator 24, an operation switch 25 for emergency communication, an antenna duplexer 26, and a receiver 27. , Switch unit 28, low frequency amplification unit 29, speaker 30, MSK data demodulation unit 31, CPU 32, ROM 33 and display unit 34.

【0027】

Here, the transmission unit 23 operates when a press-to-talk switch (hereinafter referred to as PTT switch) (hereinafter referred to as PTT switch) (hereinafter referred to as PTT switch) (hereinafter referred to as PTT switch) (hereinafter referred to as PTT switch) is operated, and the transmission signal is modulated by the voice signal output from the microphone 22 to modulate the carrier wave. Is generated and transmitted from the antenna 21 via the antenna duplexer 26. Further, at the start of transmission, the transmission unit 23 transmits an MSK-modulated transmission signal based on the group number data output from the CPU 32, and then transmits a transmission signal modulated by an audio signal. The operation switch 25 is operated at the time of emergency communication, etc., and at the time of operation, the transmitter 23 is forcibly operated by operating the PTT switch in conjunction with the operation, and the PLL (Phase-Locked Loop). By changing the channel oscillation frequency of the channel oscillation unit 24 composed of the above to a predetermined frequency, the transmission unit 23 forcibly sets the transmission frequency to f._3aChange to. As will be described later, this forced transmission has a transmission frequency f._3aIs done on the condition that is not used. The receiving unit 27 demodulates the received signal input via the antenna 21 and the antenna duplexer 26 into a low frequency signal and outputs it to the switch unit 28 and the MSK data demodulation unit 31. The switch unit 28 has a connection signal S._ONIs output from the CPU 32, the received sound signal demodulated by the receiving unit 27 is output to the low frequency amplification unit 29. The MSK data demodulation unit 31 converts the MSK signal included in the received sound signal into digital data and outputs it to the CPU 32. In the low frequency amplification unit 29, the gain is freely set by the volume adjustment volume (not shown), and the volume control signal S_VOLIs output from the CPU32, it is automatically set to the specified volume regardless of the volume volume setting.

【0028】

The CPU32 executes reception control processing, warning control processing, and the like. In the reception control process, the CPU32 determines whether or not the digital data output from the MSK data demodulation unit 31 contains the group number data corresponding to the group number of its own station, and when it determines that it is included. Connection signal S_ONIs output to control the switch unit 28 to the connected state. On the other hand, the warning control process is a process performed to stop the transmission when there is an emergency communication, and an alarm sound is emitted from the speaker 30. Specifically, the CPU 32 first determines whether or not the digital data output from the MSK data demodulation unit 31 includes predetermined emergency signal data. When it is determined that it is included, it is determined that it is an emergency contact communication, the alarm sound data stored in ROM 33 is read, and the read alarm sound data is digital-to-analog converted by the built-in D / A conversion unit. .. Then, the converted alarm sound signal S_AIs output to the input section of the low frequency amplification section 29, and the volume control signal S is sent to the low frequency amplification section 29._VOLBy outputting, the volume is controlled to be louder than the normal volume. As a result, the speaker 30 emits an alarm sound. In addition, the CPU32 has a connection signal S with respect to the switch unit 28._ONIs output to output the received sound signal to the low frequency amplification unit 29. As a result, the received sound is emitted from the speaker 30 even during transmission.

【0029】

In this example, when there is an emergency contact communication, it warns that the transmission will be stopped manually, but when the emergency signal data is recognized, the CPU32 will stop the transmission signal S._SIs output to the transmission unit 23, transmission stop control may be performed to immediately automatically stop the transmission by the transmission unit 23. Further, the voice message data may be stored in the ROM 33 in advance instead of the alarm sound data, and the voice message data may be converted into an analog signal by the D / A conversion unit and output to the low frequency amplification unit 29. Further, when the emergency signal data and the alarm sound signal or the voice message signal are included in the transmission signal and transmitted, and the CPU 32 determines that the emergency signal data is included, the connection signal S_ONThe alarm sound based on the received alarm sound signal or voice message signal may be emitted from the speaker 30 by outputting.

【0030】

Next, the configuration of the A repeater 11 will be described with reference to FIG.

【0031】

As shown in the figure, the A repeater 11 includes an antenna 41, an antenna duplexer 42, a transmitter 43, a receiver 44, a CPU 45, and a ROM 46. In the A repeater 11, the transmission frequency and the reception frequency are f, respectively._2a(In communication systems 2b to 2n, f_2b~ f_2n) And f_1a(In communication systems 2b to 2n, f_1b~ f_1n) Is assigned in advance, and the transmission frequency f transmitted from the slave unit 4_1aBy receiving and demodulating the transmission signal of, and modulating the carrier wave using the demodulated signal as a modulation signal, f_2aIt transmits at the transmission frequency of. As a result, the A repeater 11 transmits the transmission signal transmitted from the arbitrary slave unit 4 to all the other slave units 4.

【0032】

Next, the configuration of the B repeater 13 will be described with reference to FIG.

【0033】

As shown in the figure, the B repeater 13 includes an antenna 51, a receiver 52, a CPU 53, and a RAM 54. Here, the CPU 53 and the RAM 54 constitute a recording means, and the CPU 53 converts the received sound signal received by the receiving unit 52 into analog-digital and stores the converted digital data in the RAM 54. In addition, in the B repeater 13, f for emergency communication from the slave unit 4_3a(In communication systems 2b to 2n, f_3b~ f_3n) Is transmitted, the received signal is temporarily stored in the RAM 54, and then communicated with the A repeater 11 via the interface unit 12.

【0034】

Next, the overall operation of the wireless communication system 1 will be described.

【0035】

First, the operation in the normal state will be described. In the normal state, for example, the slave unit 4a has a transmission frequency f._1aWhen transmitted with, the A repeater 11 receives the transmission signal, demodulates it, and transmits the demodulated signal at the transmission frequency f._2aSend with. As a result, the other slave units 4b to 4n can receive the transmission signal from the slave unit 4a. In this case, since the slave unit 4a transmits and receives by the semi-duplex method, the speaker 30 does not emit the received sound. On the other hand, when the CPU32 of the slave units 4b to 4n determines that the group number data of its own station is included, the connection signal S_ONIs output, the received sound is emitted from the speaker 30. Then, for example, the slave unit 4b called by the slave unit 4a has a transmission frequency f._1aWhen responding with, the A repeater 11 receives the transmission signal, demodulates it, and transmits the demodulated signal to the transmission frequency f._2aSend with. As a result, mutual communication is performed between the two handsets 4a and 4b.

【0036】

Next, when transmission / reception is being performed between the slave units 4 and 4, the operation when another slave unit 4 performs emergency contact communication will be described.

【0037】

For example, when the slave units 4a and 4b are transmitting and receiving each other and the operation switch 25 is operated on the slave unit 4n side, the CPU 32 of the slave unit 4n has a transmission frequency f._3aCheck if emergency contact communication is currently in progress. In this case, the CPU32 has a transmission frequency f based on whether or not the emergency signal data described later is transmitted._3aIt is possible to determine the presence or absence of emergency contact communication by. The CPU 32 causes the receiving unit 27 to receive a so-called scan, and the transmission frequency f._3aTransmission frequency f when the reception level of the received signal for_3aIt can also be determined that the emergency contact communication by is not performed. Transmission frequency f_3aWhen it is determined that the emergency communication is not performed by the CPU32, the CPU32 sends the transmission frequency f to the transmitter 23._3nStart sending by. Then, when the operator speaks to the microphone 22, f_3nThe audio signal is transmitted at the transmission frequency of. On the other hand, the receiver 52 of the B repeater 13 is f._3nWhen the transmission frequency of is received and the reception level exceeds a predetermined value, the carrier detection signal S_KIs output to CPU53. As a result, the CPU 53 determines that the emergency communication has been performed, and subsequently stores the audio signal output from the receiving unit 52 in the RAM 54 after analog-digital conversion by the built-in A / D conversion unit. Next, the CPU 53 reads the voice signal stored in the RAM 54, and the emergency signal data indicating the emergency communication and the identification data D for identifying the communication system to which the own station belongs._SIs added, and then communicates with the A repeater 11 via the interface unit 12. In this case, the interface unit 12 also communicates with the interface unit 12 in the other communication system 2 via the communication line 14. Next, the CPU 45 of the A repeater 11 in each communication system 2 determines that the emergency communication has been performed based on the emergency signal data, and outputs the emergency signal data and the voice signal to the transmission unit 43. The transmission unit 43 transmits an MSK-modulated transmission signal based on the emergency signal data, and also transmits a frequency-modulated transmission signal based on the audio signal.

【0038】

As a result, in each of the slave units 4a to 4 (n-1) in each communication system 2, the CPU32 determines that emergency communication is being performed by discriminating the emergency signal data demodulated by MSK, and determines that emergency communication is being performed, and the frequency is low. Volume control signal S to amplification unit 29_VOLIs output to control the volume to a high volume, and the alarm sound data corresponding to the emergency signal data is read from the ROM 33 and emitted from the speaker 30. Next, the CPU32 receives the connection signal S._ONIs output to control the switch unit 28 to the connected state, so that the sound received from the receiving unit 27 is emitted from the speaker 30. In parallel with these processes, the CPU32 receives the identification data D._SThe transmitted group number of the communication system 2 is displayed on the display unit 34 based on the above. As a result, the operator of each slave unit 4 can receive the transmitted group number of the communication system 2 and the contents of the emergency communication communication performed by the slave unit 4n. In this case, the operator of the handset 4 during transmission can immediately know that the emergency communication is being performed by the alarm sound emitted, and can stop the transmission and receive the emergency communication. it can. When the handset 4 during transmission stops transmission, the operator who has performed emergency contact communication transmits the subsequent transmission at the transmission frequency f._1aThe operator of each slave unit 4 can perform with, and the operator of each slave unit 4 is transmitted via the A repeater 11._1aTransmission signal can be received as it is. As described above, according to the wireless communication system 1, it is possible to perform emergency communication with priority and reliability.

【0039】

Next, the emergency communication will be described when a failure such as running out of ink, running out of paper, or a broken shaft of the rotary press occurs in the device 3. The device 3 has a failure signal S according to the content of the failure.₁~ S_mAnd the identification data D of the own station_SIs output to the A repeater 11 via the wired communication line 5 and the interface unit 12. In this case, the interface unit 12 communicates the same communication signal to the interface unit 12 in the other communication system 2 via the communication line 14. Next, the CPU 45 of the A repeater 11 in each communication system 2 receives the input failure signal S.₁~ S_mAnd the identified failure signal S₁~ S_mAlarm data D according to the type of_AIs read from ROM46. Next, the CPU 45 reads out the alarm data D._AIdentification data D sent_SIs output to the transmitter 43. The transmitter 43 is the alarm data D output from the CPU 45._AAnd identification data D_SAfter MSK modulation based on, transmission frequency f_2aSend by.

【0040】

In this case, each slave unit 4 in each communication system 2 receives a transmission signal from the A repeater 11, and predetermined alarm data is included in the demodulated signal demodulated by the CPU 32 of each slave unit 4 by the MSK data demodulation unit 31. D_AIs included or not. When it is determined that it is included, the CPU32 sends the volume control signal S to the low frequency amplification unit 29._VOLIt is controlled to a loud volume by outputting, and alarm data D_AThe alarm sound data corresponding to is read from the ROM 33 and emitted from the speaker 30, and the alarm data D_AFailure details corresponding to and identification data D_SThe device number of the device 3 in the communication system 2 corresponding to the above is displayed on the display unit 34. Next, the CPU32 receives the connection signal S._ONIs output to control the switch unit 28 to the connected state, so that the sound received from the receiving unit 27 is emitted from the speaker 30. As a result, the operator of each slave unit 4 in all communication systems 2 can know that a failure has occurred in the device 3 in a specific communication system 2, and the details of the failure can be determined depending on the type of alarm sound. As a result of being able to know immediately, it is possible to take a quick response. Since the alarm sound is also emitted from the slave unit 4 that is transmitting, the operator of the slave unit 4 stops the transmission, so that the emergency contact communication regarding the device 3 after that can be performed._1aIt is possible to transmit and receive between each slave unit 4 and 4 using the transmission frequency of.

【0041】

On the other hand, when transmission / reception is performed between the slave units 4a and 4b as in the above example, the CPU 32 of each slave unit 4a and 4b has the predetermined alarm data D in the demodulated signal demodulated by the MSK data demodulation unit 31._AWhen it is determined that is included, the alarm control process is executed. As a result, the transmission is stopped by the operator.

【0042】

The present invention is not limited to the above-described embodiment, and its configuration can be changed as appropriate. For example, in the present embodiment, an example used for maintenance and inspection of a printing machine has been described, but the present invention is not limited to this, and for example, it can be used for a communication system for maintenance and guidance of an airplane, and emergency contact can be made. It can be applied to all communication systems that require communication. Further, in this embodiment, an example in which emergency communication is simultaneously communicated to all communication systems 2 has been described, but it is of course possible to perform emergency communication in units of 2 units of each communication system.

【0043】

[Effect of the invention]

As described above, according to the transmission / reception device according to claims 1 to 4, the transmission / reception device performs alarm control or transmission for stopping transmission when a predetermined signal is included in the received reception signal. By performing the stop control, the operator who has transmitted a predetermined signal can reliably and preferentially perform emergency communication and the like without causing interference in other transmission / reception devices. Further, by emitting a voice message or an alarm sound from the speaker during the emergency communication, it is possible to reliably communicate with the operator of the other transmission / reception device. Further, by controlling the received sound at that time to be louder than the received volume in the normal state, the operator can more surely understand that the emergency contact communication or the like has been performed. [0044]

Further, according to the relay device according to claims 5 to 7, a communication signal such as a device abnormality that occurs in an external device such as a mass-produced device can be transmitted to each transmission / reception device without causing interference.

【0045】

Further, according to the wireless communication system according to claims 8 to 10, when a pair of transmission / reception devices transmit and receive, a voice message, an alarm sound, an alarm control signal, or a transmission stop control signal is transmitted from the relay device. As a result, transmission / reception between transmission / reception devices can be stopped, and abnormalities of external devices can be transmitted to all transmission / reception devices. Further, when a plurality of wireless communication systems are provided, the relay device transmits an alarm control signal and a transmission stop control signal to each transmission / reception device in the plurality of wireless communication systems, so that the relay device can be used in the plurality of wireless communication systems. All transmitters and receivers can be contacted at once. In this case, by adding the identification data, the operator of each transmission / reception device can immediately identify the external device or the like in which the abnormality has occurred.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram of the wireless communication system which concerns on embodiment of this invention.

[Figure 2]

It is a block diagram of the slave unit which concerns on embodiment of this invention.

[Fig. 3]

It is a block diagram of A repeater which concerns on embodiment of this invention.

[Fig. 4]

It is a block diagram of the B repeater which concerns on embodiment of this invention.

[Explanation of symbols]

1 Wireless communication system 2 communication system 3 equipment 4a ~ 4n handset 6 Relay device 11 A repeater 13 B repeater