Wireless communication system and relay device

Abstract

This wireless communication system includes a wireless communication system which includes: a transmission device and a reception device that pre-register each other as a wireless communication destination; and a relay device that relays wireless communications between the reception device and the transmission device. The transmission device includes a transmission device control unit. The reception device includes a reception device control unit. The transmission device control unit and the reception device control unit execute at least one of: a step for transmitting, to the relay device which was detected by a search, transmission device connection information including transmission device address information, which is address information for the transmission device, and connection destination reception device address information, which is address information for the reception device registered to the transmission device as a connection destination; and a step for transmitting, to the relay device detected by the search, reception device connection information including reception device address information, which is address information for the reception device, and connection destination transmission device address information, which is address information for the transmission device registered to the reception device as a connection destination.

Description

[Technical Field]

[0001] The present invention relates to a wireless communication system and a relay device. [Background technology]

[0002] It is known that wireless communication between a transmitter and a receiver that are located far apart is relayed by a repeater placed along the communication path between them. Patent Document 1 discloses a method for setting a relay route when wireless communication between a master unit and a slave unit that are located far apart is relayed by a repeater. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-074281 Summary of the Invention [Problem to be solved by the invention]

[0004] In the setting method described in Patent Document 1, a repeater is registered in both a master device and a slave device that have each registered each other as wireless communication destinations, thereby allowing the start of relay communication via the repeater. Registering a repeater in the master device and the slave device is performed in two steps. Specifically, in the first step, the repeater is registered in the master device. In this step, an operator sets the frequency channels of the master device and the repeater, places both the master device and the repeater in registration mode, and then registers the repeater in the master device while checking the communication status of the repeater. In the next step, the master device instructs the repeater to access the slave device, and the instructed repeater accesses the slave device. This registers the repeater in the slave device. Since the repeater accesses the slave device in response to the access instruction from the master device, the slave devices that the repeater can access can be limited to only those slave devices registered in the master device. This prevents the repeater from selecting the wrong relay destination.

[0005] However, in the method described in Patent Document 1, it is necessary to individually register the repeater (relay device) to the master device (receiving device) and the slave device (transmitting device). In addition, each registration operation is cumbersome. Therefore, it is not possible to start relaying wireless communication by the repeater device with a simple operation.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a wireless communication system that allows relaying of wireless communication between a receiving device and a transmitting device by a relay device to be started with a simple operation while avoiding relay errors.

[0007] Another object of the present invention is to provide a relay device that can start relaying wireless communications between a receiving device and a transmitting device with a simple operation while avoiding relay errors. [Means for solving the problem]

[0008] In this specification, the term "relay device" includes a relay communication device (hereinafter sometimes referred to as a "relay device"), which is a type of communication device. The term "receiving device" includes a receiver, which is a type of communication device. The term "receiving device" includes a relay communication device registered in the receiver as a wireless communication destination, and a relay receiver that performs the same receiving function as a receiver for the "relay device." The term "relay receiver" is not limited to a device registered in the receiver as a wireless communication destination, but also includes a device registered in another relay receiver as a wireless communication destination. The term "transmitting device" includes a transmitter, which is a type of communication device. The term "transmitting device" includes a relay communication device registered in the transmitter as a wireless communication destination, and a relay transmitter that performs the same transmitting function as a transmitter for the "relay device." The term "relay transmitter" is not limited to a device registered in the transmitter as a wireless communication destination, but also includes a device registered in another relay transmitter as a wireless communication destination. The term "relay device" relays wireless communication between a "relay device" and a "transmitting device," which have each registered each other as a wireless communication destination in advance.

[0009] In one embodiment of the present invention, a wireless communication system is configured to transmit information to be transmitted from a transmitter to a receiver, and includes one or more repeaters on a communication path (wireless communication path) between the transmitter and the receiver. In this case, on the communication path, another communication device (another repeater or transmitter) adjacent to a certain repeater (this repeater corresponds to a "repeater") on the upstream side (i.e., on the transmitter side) is the "transmitting device," and another communication device (another repeater or receiver) adjacent to the repeater on the downstream side (i.e., on the receiver side) is the "receiving device." When the "transmitting device" is another repeater, the other repeater may be referred to as a "repeater transmitter." Furthermore, when the "receiving device" is another repeater, the other repeater may be referred to as a "repeater receiver."

[0010] One embodiment of the present invention provides a wireless communication system including a transmitting device and a receiving device that have each registered each other as wireless communication destinations in advance, and a relay device that relays wireless communication between the receiving device and the transmitting device. The transmitting device includes a transmitting device control unit that executes a first relay device search step of searching for a relay device in a pairing mode. The receiving device includes a receiving device control unit that executes a second relay device search step of searching for a relay device in the pairing mode. The transmitting device control unit and the receiving device control unit execute at least one of the following steps: transmitting, to the relay device detected by the search, transmitting device connection information including transmitting device address information that is address information of the transmitting device and destination receiving device address information that is address information of the receiving device registered as a destination with the transmitting device; and transmitting, to the relay device detected by the search, receiving device connection information including receiving device address information that is address information of the receiving device and destination transmitting device address information that is address information of the transmitting device registered as a destination with the receiving device. The relay device includes a relay device control unit that executes a receiving device search step of searching for a receiving device during pairing mode, and receiving receiving device connection information from the receiving device detected by the search, the receiving device connection information including receiving device address information that is address information of the receiving device and destination transmitting device address information that is address information of the transmitting device that has been registered as a connection destination to the receiving device, and a transmitting device search step of searching for a transmitting device during pairing mode, and receiving transmitting device connection information from the transmitting device detected by the search, the transmitting device connection information including transmitting device address information that is address information of the transmitting device and destination receiving device address information that is address information of the receiving device that has been registered as a connection destination to the transmitting device.Then, one of the receiving device control unit, the transmitting device control unit, and the relay device control unit executes a determination step to determine whether the relay device will transition from the pairing mode to a relay communication mode in which wireless communication between the receiving device and the transmitting device is relayed based on at least one of destination transmitting device address information, which is address information of the transmitting device that has been registered as a destination in the receiving device, and destination receiving device address information, which is address information of the receiving device that has been registered as a destination in the transmitting device.

[0011] According to this configuration, one of the receiving device control unit of the receiving device, the transmitting device control unit of the transmitting device, and the relay device control unit of the relay device determines whether to transition from pairing mode to relayed communication mode based on at least one of the destination receiving device address information of the destination of the transmitting device and the destination transmitting device address information of the destination of the receiving device. Because the determination of whether to transition to relayed communication mode is based on at least one of the destination receiving device address and the destination transmitting device address, when transitioning from pairing mode to relayed communication mode, it is guaranteed that the receiving device and the transmitting device detected by the search have each other registered as wireless communication destinations in advance. Therefore, relay errors can be avoided.

[0012] Furthermore, since the search for receiving devices, the search for transmitting devices, and the decision on whether to transition to relay communication mode are a series of processes during pairing mode, relay communication can be started with simple operations compared to when the registration process is performed multiple times.

[0013] Therefore, relaying of wireless communication between a receiving device and a transmitting device by a relay device can be started with a simple operation while avoiding relay errors, and therefore a wireless communication system including a relay device can be easily constructed.

[0014] In one embodiment of the present invention, in the determination step, the relay device control unit determines whether to transition to the relay communication mode based on at least one of a comparison between the receiving device address information received by the relay device from the detected receiving device and the destination receiving device address information received by the relay device from the detected transmitting device, and a comparison between the transmitting device address information received by the relay device from the detected transmitting device and the destination transmitting device address information received by the relay device from the detected receiving device.

[0015] According to this configuration, when a transition condition is met, the relay device transitions from the pairing mode to the relayed communication mode, including one or both of the following: the receiving device address information received from the receiving device matches the destination receiving device address information received from the transmitting device, and the transmitter address information received from the transmitting device matches the destination transmitter address information received from the receiving device.On the other hand, when the transition condition is not met, the relay device does not transition to the relayed communication mode.

[0016] In one embodiment of the present invention, in the determining step, the relay device control unit determines to transition to the relay communication mode when the receiving device address information received by the relay device from the detected receiving device matches the destination receiving device address information received by the relay device from the detected transmitting device and when the transmitting device address information received by the relay device from the detected transmitting device matches the destination transmitting device address information received by the relay device from the detected receiving device.The relay device control unit determines not to transition to the relay communication mode when the receiving device address information received by the relay device from the detected receiving device does not match the destination receiving device address information received by the relay device from the detected transmitting device, or when the transmitting device address information received by the relay device from the detected transmitting device does not match the destination transmitting device address information received by the relay device from the detected receiving device.

[0017] According to this configuration, if the detected receiving device and the detected transmitting device have both registered each other as wireless communication destinations in advance, the receiving device address information received from the detected receiving device matches the destination receiving device address information received from the detected transmitting device. Therefore, the detected receiving device and transmitting device can transition to the relay communication mode while ensuring that they have both registered each other as wireless communication destinations in advance.

[0018] Similarly, if the detected receiving device and the detected transmitting device have both registered each other as wireless communication destinations in advance, the transmitting device address information received from the detected transmitting device will match the destination transmitting device address information received from the detected receiving device. Therefore, the detected receiving device and transmitting device can transition to the relayed communication mode while ensuring that they have both registered each other as wireless communication destinations in advance.

[0019] Although it is possible to set the condition for switching to the relay communication mode based on either a match between the receiving device address information and the destination receiving device address information or a match between the transmitting device address information and the destination transmitting device address information, setting both of these conditions for switching to the relay communication mode provides a doubly guaranteed guarantee that the receiving device and the transmitting device have registered each other as wireless communication destinations in advance, thereby avoiding relay errors by the relay device.

[0020] Therefore, relaying of wireless communication between the receiving device and the transmitting device by the relay device can be started with a simpler operation while avoiding relay errors.

[0021] In one embodiment of the present invention, the receiving device connection information and the transmitting device connection information include group identification information assigned to the receiving device and the transmitting device, respectively. The relay device control unit determines not to transition to the relayed communication mode in the determining step when the group identification information included in the receiving device connection information received by the relay device from the detected receiving device does not match the group identification information assigned to the relay device, or when the group identification information included in the transmitting device connection information received by the relay device from the detected transmitting device does not match the group identification information assigned to the relay device.

[0022] According to this configuration, the same group identification information (group ID) is assigned in advance to the receiving device, transmitting device, and relay device that are to communicate wirelessly. The relay device transitions to relayed communication mode only if the group IDs received from the receiving device and transmitting device detected by the search match the group ID assigned to the relay device. This prevents wireless communication from being initiated by receiving devices, transmitting devices, and relay devices that are not intended to communicate wirelessly.

[0023] In one embodiment of the present invention, the relay device control unit executes, in the receiving device search step, a step of transmitting, to the receiving device detected by the search, one or both of the transmitter address information and the destination receiver address information included in the transmitter connection information received from the transmitter detected in the transmitter search step.The receiving device control unit executes a step of receiving, from the relay device detected in the second relay device search step, the transmitter address information and / or the destination receiver address information included in the transmitter connection information.The receiving device control unit determines, in the determination step, whether the relay device will transition from the pairing mode to the relayed communication mode based on at least one of comparing the receiver address information of the receiving device with the destination receiver address information included in the transmitter connection information and comparing address information of the transmitter registered as a destination in the receiving device with the transmitter address information included in the transmitter connection information.

[0024] In one embodiment of the present invention, the relay device control unit executes, in the transmitter search step, a step of transmitting, to the transmitter detected by search, one or both of the receiving device address information and the destination transmitter address information included in the receiving device connection information received from the receiving device detected in the receiving device search step.The transmitter control unit then executes a step of receiving, from the relay device detected in the first relay device search step, one or both of the receiving device address information and the destination transmitter address information included in the receiving device connection information.The transmitter control unit then determines, in the determination step, whether the relay device will transition from the pairing mode to the relayed communication mode based on at least one of comparing the transmitter address information of the transmitter with the destination transmitter address information included in the receiving device connection information and comparing address information of the receiving device registered as a destination in the transmitter with the receiving device address information included in the receiving device connection information.

[0025] In one embodiment of the present invention, when the power of the relay device is turned on and one or both of the receiving device and the transmitting device to which communication is to be relayed are not registered, the relay device enters the pairing mode.

[0026] According to this configuration, if one or both of the receiving device and transmitting device to which communication is to be relayed are not registered, the relay device will enter pairing mode after powering on. In other words, in this case, the relay device will enter pairing mode simply by turning on the power, without any other operation. Since no separate operation is required to enter pairing mode, relaying of wireless communication between the receiving device and transmitting device by the relay device can be started with even fewer operations.

[0027] In one embodiment of the present invention, the receiving device enters the pairing mode when a failure in wireless communication with the transmitting device occurs, and the transmitting device enters the pairing mode when a failure in wireless communication with the receiving device occurs.

[0028] In one embodiment of the present invention, the transmitting device is a transmitter or other repeater.

[0029] In one embodiment of the present invention, the receiving device is a receiver or other repeater.

[0030] The transmitter may be connected to a production device.

[0031] The receiver may be connected to an alarm device.

[0032] According to one embodiment of the present invention, a relay device is connected to a transmitting device and a receiving device that have each registered each other in advance as wireless communication destinations, and relays wireless communication between the receiving device and the transmitting device, the relay device including a receiving device search step of searching for a receiving device in a pairing mode, and receiving, from the receiving device detected by the search, receiving device connection information including receiving device address information that is address information of the receiving device and destination transmitting device address information that is address information of the transmitting device that has been registered as a connection destination with the receiving device; and a receiving device search step of searching for a transmitting device in the pairing mode, and receiving, from the transmitting device detected by the search, receiving device connection information including receiving device address information that is address information of the transmitting device and destination transmitting device address information that is address information of the transmitting device. Provided is a relay device including a control unit that executes a transmitting device search step of receiving transmitting device connection information including destination receiving device address information, which is address information of the receiving device that has been registered as a connection destination in the transmitting device, and a determination step of determining whether to transition from the pairing mode to a relay communication mode that relays wireless communication between the receiving device and the transmitting device based on the receiving device address information received from the detected receiving device, the destination receiving device address information received from the detected transmitting device, the transmitting device address information received from the detected transmitting device, and the destination transmitting device address information received from the detected receiving device.

[0033] Moreover, one embodiment of the present invention provides a relay device that is connected to a transmitting device and a receiving device that have each registered each other in advance as wireless communication destinations, and relays wireless communication between the receiving device and the transmitting device, and includes a control unit that executes a transmitting device search step of searching for a transmitting device during a pairing mode, and receiving transmitting device connection information including transmitting device address information that is address information of the transmitting device from the transmitting device detected by the search, and a receiving device search step of searching for a receiving device during the pairing mode, and transmitting the transmitting device address information included in the transmitting device connection information received from the transmitting device detected by the search to the receiving device detected by the search.

[0034] Moreover, one embodiment of the present invention provides a relay device that is connected to a transmitting device and a receiving device that have each registered each other in advance as wireless communication destinations, and relays wireless communication between the receiving device and the transmitting device, and includes a control unit that executes a receiving device search step of searching for a receiving device during a pairing mode, and receiving receiving device connection information including receiving device address information that is address information of the receiving device from the receiving device detected by the search, and a transmitting device search step of searching for a transmitting device during the pairing mode, and transmitting the receiving device address information included in the receiving device connection information received from the receiving device detected by the search to the transmitting device detected by the search. [Brief explanation of the drawings]

[0035] [Figure 1A-1B] 1A and 1B are conceptual diagrams showing the configuration of a wireless communication system according to a first embodiment of the present invention when applied to a production system. [Figure 2A] FIG. 2A is a block diagram showing an example of the electrical configuration of a wireless communication system including a receiver, a transmitter, and a repeater. [Figure 2B] FIG. 2B is a block diagram showing an example of the electrical configuration of a wireless communication system including a receiver, a transmitter, and a repeater. [Figure 3]FIG. 3 is a block diagram showing the contents stored in the information memory of the receiver. [Figure 4] FIG. 4 is a block diagram showing the contents stored in the information memory of the transmitter. [Figure 5] FIG. 5 is a block diagram showing the contents stored in the information memory of the repeater. [Figure 6] FIG. 6 is a flowchart showing a procedure for starting relay communication between the receiver and the transmitter by one of the relay devices. [Figure 7] FIG. 7 is a diagram for explaining receiver-transmitter pairing (step S2 in FIG. 6). [Figure 8] FIG. 8 is a diagram for explaining the receiving device-repeater-transmitting device pairing (step S5 in FIG. 6). [Figure 9] FIG. 9 is a flowchart illustrating the processing flow in the first receiver pairing mode of the receiver. [Figure 10] FIG. 10 is a flowchart illustrating the flow of processing in the first transmitter pairing mode of the transmitter. [Figure 11] FIG. 11 is a flow chart for explaining the flow after the power supply of the repeater is turned on. [Figure 12] FIG. 12 is a flowchart illustrating the process flow in the repeater pairing mode of the repeater. [Figure 13A] FIG. 13A is a flowchart illustrating the processing flow in the second transmitter pairing mode of the transmitter. [Figure 13B] FIG. 13B is a flowchart illustrating the processing flow in the second transmitter pairing mode of the transmitter. [Figure 14] FIG. 14 is a flowchart for explaining the flow of the first repeater pairing process (step S81 in FIG. 12) of the repeater. [Figure 15A] FIG. 15A is a flowchart illustrating the processing flow in the second receiver pairing mode of the receiver. [Figure 15B]FIG. 15B is a flowchart illustrating the processing flow in the second receiver pairing mode of the receiver. [Figure 16] FIG. 16 is a flowchart for explaining the flow of the second repeater pairing process (step S82 in FIG. 12) of the repeater. [Figure 17] FIG. 17 is a flowchart for explaining the flow of the repeater determination and registration process (step S83 in FIG. 12). [Figure 18] FIG. 18 is a flowchart showing the procedure when another repeater is newly placed on the path between the repeater and the transmitter. [Figure 19] FIG. 19 is a diagram for explaining receiving device-repeater-transmitting device pairing (step S163 in FIG. 18) when another repeater is newly placed on the path between the repeater and the transmitter. [Figure 20] FIG. 20 is a flowchart showing the procedure when another relay is newly placed on the path between the receiver and the relay transmitter. [Figure 21] FIG. 21 is a diagram for explaining receiving device-repeater-transmitting device pairing (step S173 in FIG. 20) when another repeater is newly placed on the path between the receiver and the repeater transmitter. [Figure 22] FIG. 22 is a flowchart for explaining the transition of the control mode of the repeater. [Figure 23] FIG. 23 is a block diagram showing the contents stored in the information memory of a receiver included in a wireless communication system according to the second embodiment of the present invention. [Figure 24] FIG. 24 is a diagram for explaining the receiving device-repeater-transmitting device pairing performed in the wireless communication system. [Figure 25] FIG. 25 is a flowchart illustrating the flow of processing in the second receiver pairing mode of the receiver included in the wireless communication system. [Figure 26] FIG. 26 is a flowchart illustrating the processing flow in the second receiver pairing mode. [Figure 27]FIG. 27 is a flowchart illustrating the flow of the second relay pairing process of the relay included in the wireless communication system. [Figure 28] FIG. 28 is a flowchart illustrating the flow of the second relay pairing process. [Figure 29] FIG. 29 is a block diagram showing the contents stored in an information memory of a transmitter included in a wireless communication system according to the third embodiment of the present invention. [Figure 30] FIG. 30 is a diagram for explaining the receiving device-repeater-transmitting device pairing performed in the wireless communication system. [Figure 31] FIG. 31 is a flowchart illustrating a processing flow in the second transmitter pairing mode of the transmitter included in the wireless communication system. [Figure 32] FIG. 32 is a flowchart illustrating the processing flow in the second transmitter pairing mode. [Figure 33] FIG. 33 is a flowchart illustrating the flow of the first relay pairing process of the relay included in the wireless communication system. [Figure 34] FIG. 34 is a flowchart illustrating the flow of the first repeater pairing process. DETAILED DESCRIPTION OF THE INVENTION

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0037] 1A and 1B are conceptual diagrams showing a configuration in which a wireless communication system 1 according to a first embodiment of the present invention is applied to a production system 10. The production system 10 includes a production device 11 and a notification device 12 associated with the production device 11. The production device 11 may be located in a factory 13. The notification device 12 may be located in an office 14 separate from the factory 13. The factory 13 and the office 14 may be located in the same building. In this case, the factory 13 and the office 14 may be located on the same floor or on different floors. The factory 13 and the office 14 may be located in different buildings. In this case, the building in which the factory 13 is located and the building in which the office 14 is located may be on the same site.

[0038] The production device 11 includes a sensor 15, a device 16, etc. The device 16 includes a switch, a relay, etc.

[0039] The alarm device 12 includes at least one of a rotating light, a signal light, a voice alarm, a warning buzzer, and a warning display (for example, a character board). In the example of Figures 1A and 1B, the alarm device 12 includes a signal light.

[0040] The wireless communication system 1 includes a receiver 2 and a transmitter 3 that communicate wirelessly with each other. The communication method for wireless communication between the receiver 2 and the transmitter 3 is, for example, IEEE802.15.1 (Bluetooth (registered trademark), hereinafter referred to as "Bluetooth (registered trademark)"). The receiver 2 is connected to an alarm device 12. In the example of FIGS. 1A and 1B, one receiver 2 is associated with one alarm device 12, but one receiver 2 may be associated with multiple alarm devices 12.

[0041] The transmitter 3 is connected to the production equipment 11. Signals from the sensors 15 and equipment 16 may be given to the transmitter 3 via multiple (for example, six) input contacts. The signals from the sensors 15 and equipment 16 may be input to the production equipment 11 via an abnormality panel (not shown) or the like, rather than directly. Monitoring of the production equipment 11 by the transmitter 3 may be performed unmanned. In the example of FIGS. 1A and 1B, one transmitter 3 is associated with one production equipment 11, but one transmitter 3 may be associated with multiple production equipment 11.

[0042] The wireless communication system 1 further includes a repeater 4 that repeats wireless communication between the receiver 2 and the transmitter 3. When the distance between the alarm device 12 and the production device 11 is long or when there are buildings or walls between the alarm device 12 and the production device 11, wireless communication between the receiver 2 connected to the alarm device 12 and the transmitter 3 connected to the production device 11 may be poor. In particular, Bluetooth (registered trademark) is a short-range wireless communication technology, and the communication distance is not long. Even in such a case, by placing a repeater 4 on the path between the receiver 2 and the transmitter 3, wireless communication between the receiver 2 and the transmitter 3 can be performed well. The number of repeaters 4 placed on the path between the receiver 2 and the transmitter 3 may be one as shown in FIG. 1A or multiple (three in the example of FIG. 1B) repeaters 4 may be placed on the path between the receiver 2 and the transmitter 3. The number of repeaters 4 may be two or four or more. The number of repeaters 4 that relay wireless communication between the receiver 2 and the transmitter 3 is determined based on the distance between the alarm device 12 and the production device 11 and the status of obstacles (buildings and walls) between the alarm device 12 and the production device 11.

[0043] Depending on the status (normal or abnormal) of the production equipment 11, a signal is input from the sensor 15 or the device 16 to the transmitter 3. Upon receiving this signal, the transmitter 3 transmits wireless data corresponding to the input signal to the receiver 2. The receiver 2, upon receiving this wireless data, sends a signal to the alarm device 12. This allows the alarm device 12 to recognize the status of the production equipment 11. The alarm device 12 then notifies the status of the production equipment 11 by activating a rotating light or a signal light, issuing an audio alert using an audio alarm, sounding an alarm buzzer, displaying an abnormality on a display, or the like. This notifies the office worker around the alarm device 12 of the status of the production equipment 11. The production equipment 11 may send a signal to the transmitter 3 not only when an abnormality occurs in the production equipment 11 (such as a breakdown, a parts shortage, or a warning of a parts shortage), but also when a manager or person in charge needs to be called. Even when the production equipment 11 is normal, a signal indicating "normal" may be sent periodically, and an alert may be issued based on this signal.

[0044] 2A and 2B are block diagrams showing an example of the electrical configuration of the receiver 2, the repeater 4, and the transmitter 3. The receiver 2, the repeater 4, and the transmitter 3 are connected to a network N. The network N is a network conforming to Bluetooth (registered trademark). 2A and 2B show an example of the electrical configuration when there is one repeater 4.

[0045] Referring to FIG. 2A, the receiver 2 is, for example, a portable wireless communication terminal. The receiver 2 can stand directly or indirectly on a placing surface such as a floor. Communication devices with which to communicate wirelessly are registered in the receiver 2, and the receiver 2 communicates wirelessly with one of the registered communication devices to receive wireless data from that communication device. The receiver 2 is a communication device for receiving data. Needless to say, when performing receiver-transmitter pairing (see FIG. 7) and receiving device-repeater-transmitter pairing (see FIG. 8), which will be described later, the receiver 2 transmits connection information (pairing information).

[0046] The receiver 2 is registered with one transmitting device that is to communicate wirelessly with the receiver 2 and one repeater that is to communicate wirelessly with the receiver 2. For example, if there is no repeater 4 on the path between the receiver 2 and the transmitter 3, the receiver 2 will have the transmitter 3 registered as the transmitting device that is to communicate wirelessly, but the repeater that is to communicate wirelessly with the receiver 2 will not be registered in the receiver 2. In this case, the receiver 2 will communicate wirelessly with the transmitter 3 and receive wireless data from the transmitter 3.

[0047] 1A, when one repeater 4 is located on the path between the receiver 2 and the transmitter 3, the transmitter 3 is registered in the receiver 2 as a transmitting device with which to communicate wirelessly, and the repeater 4 is registered as a repeater with which to communicate wirelessly. In this case, the receiver 2 communicates wirelessly with the repeater 4 and receives wireless data from the repeater 4.

[0048] 1B, when multiple repeaters 4 are arranged along the path between the receiver 2 and the transmitter 3, the repeater 4 arranged closest to the receiver 2 (repeater 4B shown in FIG. 1B) is registered in the receiver 2 as the repeater with which to communicate wirelessly, and the repeater 4 arranged second from the receiver 2 (repeater 4A shown in FIG. 1B) is registered as the transmitter with which to communicate wirelessly. In this case, the receiver 2 communicates wirelessly with repeater 4B and receives wireless data from repeater 4B.

[0049] 2A, the receiver 2 includes an antenna 21, a first communication unit 22A, a control unit (receiving device control unit) 23, an information memory 24, an interface unit 25, a battery 26, a power switch 27, a clear switch 28, a storage unit 29, and a status display unit 30 (also see FIG. 1A). The antenna 21 is used for transmitting and receiving wireless data and for transmitting and receiving connection information. The antenna 21 may include a transmitting antenna and a receiving antenna separately, or may be a shared antenna. The first communication unit 22A has a Bluetooth® communication module that performs wireless communication in accordance with the Bluetooth® standard.

[0050] The control unit 23 is configured by a microcomputer equipped with a central processing unit (CPU) and memory. The memory of the control unit 23 stores information including programs executed by the central processing unit of the control unit 23 and data for calculations. The communication unit 22 performs amplification and filtering processes on the wireless data received by the antenna 21, converts the wireless data into a baseband signal, and outputs it to the control unit 23. The interface unit 25 is connected to multiple (e.g., six) output lines of the alarm device 12 via multiple (e.g., six) output contacts. The power switch 27 is a switch operated to turn the power of the receiver 2 on and off. The clear switch 28 is a switch operated to clear the contents stored in the information memory 24. The memory unit 29 stores various information.

[0051] The control unit 23 has multiple control modes. The multiple control modes are three modes: a first receiver pairing mode, a second receiver pairing mode, and a wireless communication mode. The first receiver pairing mode is a pairing mode for searching for and registering a transmitter with which to communicate wirelessly. The second receiver pairing mode is a pairing mode for searching for and registering another communication device when a deterioration in communication quality occurs with a communication device with which to communicate wirelessly. The wireless communication mode is a mode for performing wireless communication with one of the registered communication devices. When the receiver 2 is powered on, the receiver 2 is in one of these three control modes.

[0052] A first communication quality degradation flag 29A is stored in the storage unit 29. The first communication quality degradation flag 29A is a flag that indicates whether or not the quality of wireless communication between the receiver 2 and a communication device that is wirelessly communicating with the receiver 2 has degraded. Whether or not the quality of wireless communication has degraded is determined based on the communication strength (e.g., an LQI (Link Quality Indicator) value) that the communication unit 22 holds during communication. When the communication strength is lower than a threshold, the first communication quality degradation flag 29A is turned on. On the other hand, when the communication strength is equal to or greater than the threshold, the first communication quality degradation flag 29A is turned off.

[0053] The status display unit 30 displays the communication status of the receiver 2 by selectively displaying multiple colors. In this embodiment, the display colors of the status display unit 30 that indicate the communication status of the receiver 2 are green, yellow, and red. When wireless communication between the receiver 2 and the communication device is performed at high strength (when the first communication quality degradation flag 29A is off), the display color is green. When wireless communication between the receiver 2 and the communication device is performed but the communication strength is low (when the first communication quality degradation flag 29A is on), the display color is yellow. When wireless communication between the receiver 2 and the communication device is not performed, the display color is red.

[0054] In the example of FIG. 2A, the receiver 2 has a configuration capable of not only receiving but also transmitting wireless data. Specifically, the receiver 2 further includes a second communication unit 22B. The second communication unit 22B has a configuration equivalent to the second communication unit 42B of the repeater 4, which will be described later. The memory unit 29 also stores a second communication quality degradation flag 29B. The second communication quality degradation flag 49B has a configuration equivalent to the second communication quality degradation flag 49B of the repeater 4, which will be described later. The receiver 2 includes a selector switch (not shown). When this selector switch is in the on state, the function of the second communication unit 22B is enabled. The control unit 23 can then send wireless data received from a communication device (such as the transmitter 3, the repeater 4, or the repeater 4B) registered as a transmitting device with which to perform wireless communication to another communication device. In this case, since the receiver 2 performs not only a receiving function but also a transmitting function, the receiver 2 can function as a relay communication device for the wireless communication between the two communication devices.

[0055] On the other hand, when the changeover switch is in the OFF state, the function of the second communication unit 22B is disabled, and the control unit 23 cannot send wireless data to other registered communication devices. In other words, the receiver 2 only performs the receiving function.

[0056] The receiver 2 may not be configured to be capable of transmitting wireless data, but may be a communication device that is only for receiving data.

[0057] Referring to FIG. 2A, the transmitter 3 is, for example, a portable wireless communication terminal. The transmitter 3 can stand directly or indirectly on a mounting surface such as a floor. The transmitter 3 has registered therein communication devices with which to communicate wirelessly, and transmits wireless data to one of the registered communication devices by wirelessly communicating with that communication device. In this embodiment, the transmitter 3 is a communication device dedicated to transmission. Of course, it goes without saying that the transmitter 3 receives connection information of other communication devices during receiver-transmitter pairing (see FIG. 7) and receiving device-repeater-transmitter pairing (see FIG. 8), which will be described later.

[0058] The transmitter 3 is registered with one receiving device that is to communicate wirelessly with the transmitter 3 and one repeater that is to communicate wirelessly with the transmitter 3. For example, if there is no repeater 4 on the path between the receiver 2 and the transmitter 3, the receiver 2 is registered with the transmitter 3 as the receiving device that is to communicate wirelessly, but no repeater that is to communicate wirelessly with the transmitter 3 is registered with the transmitter 3. In this case, the transmitter 3 communicates wirelessly with the receiver 2 and sends wireless data to the receiver 2.

[0059] 1A, when one repeater 4 is located on the path between the receiver 2 and the transmitter 3, the receiver 2 is registered in the transmitter 3 as a receiving device with which to communicate wirelessly, and the repeater 4 is registered as a repeater with which to communicate wirelessly. In this case, the transmitter 3 communicates wirelessly with the repeater 4 and sends wireless data to the repeater 4.

[0060] 1B, when multiple repeaters 4 are arranged along the path between the receiver 2 and the transmitter 3, the repeater 4 arranged closest to the transmitter 3 (repeater 4C shown in FIG. 1B) is registered in the transmitter 3 as the repeater with which to communicate wirelessly, and the repeater 4 arranged second from the transmitter 3 (repeater 4A shown in FIG. 1B) is registered as the receiving device with which to communicate wirelessly. In this case, the transmitter 3 communicates wirelessly with repeater 4C and sends wireless data to repeater 4C.

[0061] Referring to FIG. 2A, the transmitter 3 includes an antenna 31, a communication unit 32, a control unit 33 (transmitter control unit), an information memory 34, an interface unit 35, a battery 36, a power switch 37, a clear switch 38, a storage unit 39, and a status display unit 40 (also see FIG. 1A). The antenna 31 is used to transmit wireless data and to send and receive connection information (pairing information). The communication unit 32 has a Bluetooth® communication module that performs wireless communication in accordance with the Bluetooth® standard. The control unit 33 is configured by a microcomputer equipped with a central processing unit (CPU) and memory. The memory of the control unit 33 stores information including programs executed by the central processing unit and data for calculations. The communication unit 32 converts baseband signals output from the control unit 33 into wireless data, amplifies the data, and transmits it from the antenna 31. The interface unit 35 is connected to multiple (e.g., six) input lines of the production equipment 11 via multiple (e.g., six) input contacts. The power switch 37 is a switch that is operated to turn on and off the power of the transmitter 3. The clear switch 38 is a switch that is operated to clear the contents stored in the information memory 34. The memory unit 39 stores various pieces of information.

[0062] The control unit 33 has multiple control modes. The multiple control modes are three modes: a first transmitter pairing mode, a second transmitter pairing mode, and a wireless communication mode. The first transmitter pairing mode is a pairing mode for searching for and registering a receiver with which to wirelessly communicate. The second transmitter pairing mode is a pairing mode for searching for and registering another communication device when the quality of communication with the communication device with which to wirelessly communicate deteriorates. The wireless communication mode is a mode for performing wireless communication with one of the registered communication devices. When the transmitter 3 is powered on, the transmitter 3 is in one of these three control modes.

[0063] The storage unit 39 stores a communication quality degradation flag 39A. The communication quality degradation flag 39A is a flag that indicates whether or not the quality of wireless communication between the transmitter 3 and a communication device that is wirelessly communicating with the transmitter 3 has degraded. Whether or not the communication quality of wireless communication has degraded is determined based on the communication strength (e.g., LQI value) that the communication unit 32 holds during communication. When the communication strength is lower than a threshold, the communication quality degradation flag 39A is turned on. On the other hand, when the communication strength is equal to or higher than the threshold, the communication quality degradation flag 39A is turned off.

[0064] The status display unit 40 displays the communication status of the transmitter 3 by selectively displaying multiple colors. In this embodiment, the display colors of the status display unit 40 that indicate the communication status of the transmitter 3 are green, yellow, and red. When wireless communication between the transmitter 3 and the communication device is performed at high strength (when the communication quality degradation flag 39A is off), the display color is green. When wireless communication between the transmitter 3 and the communication device is performed but the communication strength is low (when the communication quality degradation flag 39A is on), the display color is yellow. When wireless communication between the transmitter 3 and the communication device is not performed, the display color is red.

[0065] Although the transmitter 3 has been described as a communication device dedicated to transmission, the transmitter 3 may be configured to be capable of not only transmitting wireless data but also receiving wireless data.

[0066] 2B, the repeater 4 is, for example, a portable wireless communication terminal. The repeater 4 can stand directly or indirectly on a support surface such as a floor. The repeater 4 has registered therein communication devices with which to perform wireless communication (relay communication), and the repeater 4 communicates wirelessly with two of the registered communication devices, receives wireless data from one of the communication devices, and transmits the received wireless data to the other communication device. In other words, the repeater 4 relays wireless communication between the two registered communication devices.

[0067] In relay device 4 as a relay device, one receiving device that is to communicate wirelessly with relay device 4 and one transmitting device that is to communicate wirelessly with relay device 4 are registered. For example, as shown in FIG. 1A, if one relay device 4 is placed midway along the path between receiver 2 and transmitter 3, receiver 2 is registered in relay device 4 as the receiving device that is to communicate wirelessly, and transmitter 3 is registered as the transmitting device that is to communicate wirelessly. Relay device 4 as a relay device communicates wirelessly with receiver 2 and transmitter 3, receives wireless data from transmitter 3, and sends it to receiver 2.

[0068] 1B, consider a case where multiple repeaters 4 are placed along the path between the receiver 2 and the transmitter 3. For example, consider repeater 4B, which is placed closest to the receiver 2 among the multiple repeaters 4. This repeater 4B has the receiver 2 registered as a receiving device with which to communicate wirelessly, and another repeater 4 (repeater 4A shown in FIG. 1B) registered as a transmitting device with which to communicate wirelessly. Repeater 4B as a repeater communicates wirelessly with the receiver 2 and repeater 4A, receives wireless data from repeater 4A, and sends it to the receiver 2.

[0069] Next, let us consider relay 4C, which is located closest to transmitter 3 among the multiple relays 4. Another relay 4 (relay 4A shown in FIG. 1B) is registered in this relay 4C as a receiving device with which to communicate wirelessly, and transmitter 3 is registered as a transmitting device with which to communicate wirelessly. Relay 4C as a relay communicates wirelessly with relay 4A and transmitter 3, receives wireless data from transmitter 3, and sends it to relay 4A.

[0070] Furthermore, in the case where there are three or more repeaters 4 disposed between the receiver 2 and the transmitter 3, consider a repeater 4 (repeater 4A shown in FIG. 1B) disposed between two repeaters 4. Another repeater 4 (repeater 4B shown in FIG. 1B) is registered in this repeater 4A as a receiving device with which to communicate wirelessly, and another repeater 4 (repeater 4C shown in FIG. 1B) is registered as a transmitting device with which to communicate wirelessly. The repeater 4A as a repeater communicates wirelessly with repeaters 4B and 4C, receives wireless data from repeater 4C, and sends it to repeater 4B. In other words, from the perspective of repeater 4A, repeater 4B is a repeater receiver with the same functions as the receiver 2. Furthermore, from the perspective of repeater 4A, repeater 4C is a repeater transmitter with the same functions as the receiver 2.

[0071] 2B, the repeater 4 includes an antenna 41, a first communication unit 42A, a second communication unit 42B, a control unit 43 (repeater control unit, receiver control unit, transmitter control unit), an information memory 44, an interface unit 45, a battery 46, a power switch 47, a clear switch 48, a storage unit 49, and a status display unit 50 (also see FIG. 1A). The antenna 41 is used for transmitting and receiving wireless data and connection information (pairing information). The first communication unit 42A performs wireless communication with the communication unit connected to the receiver 2 side of the repeater 4 (the communication unit that receives wireless data from the repeater 4) of the two communication units that should communicate wirelessly. The second communication unit 42B performs wireless communication with the communication unit connected to the transmitter 3 side of the repeater 4 (the communication unit that sends wireless data to the repeater 4) of the two communication units that should communicate wirelessly. The first communication unit 42A and the second communication unit 42B each have a Bluetooth (registered trademark) communication module that performs wireless communication in accordance with the Bluetooth (registered trademark) standard.

[0072] The control unit 43 is configured by a microcomputer equipped with a central processing unit (CPU) and memory. The memory of the control unit 43 stores information including programs executed by the central processing unit and data for calculations. The first communication unit 42A converts the baseband signal output from the control unit 43 into wireless data, performs amplification processing, etc., and transmits the data from the antenna 41. The second communication unit 42B performs amplification processing, filtering processing, etc. on the wireless data received by the antenna 41, converts the wireless data into a baseband signal, and outputs it to the control unit 43. The interface unit 45 has a configuration equivalent to the interface unit 25 of the receiver 2. The power switch 47 is a switch operated to turn the power of the repeater 4 on and off. The clear switch 48 is a switch operated to clear the contents stored in the information memory 44. Various information is stored in the memory unit 49.

[0073] The storage unit 49 stores a first communication quality degradation flag 49A and a second communication quality degradation flag 49B. The first communication quality degradation flag 49A is a flag that indicates whether the quality of wireless communication between the repeater 4 and a communication device (receiver 2, other repeaters 4) connected on the receiver 2 side of the repeater 4 has degraded. Whether the quality of wireless communication has degraded is determined based on the communication strength (e.g., LQI value) held by the first communication unit 42A during communication. When the communication strength is lower than a threshold, the first communication quality degradation flag 49A is turned on. On the other hand, when the communication strength is equal to or greater than the threshold, the first communication quality degradation flag 49A is turned off.

[0074] The second communication quality degradation flag 49B is a flag that indicates whether the quality of wireless communication between the repeater 4 and a communication device (receiver 2, other repeaters 4) connected on the transmitter 3 side of the repeater 4 has degraded. Whether the quality of wireless communication has degraded is determined based on the communication strength (e.g., LQI value) held by the second communication unit 42B during communication. If the communication strength is lower than a threshold, the second communication quality degradation flag 49B is turned on. On the other hand, if the communication strength is equal to or greater than the threshold, the second communication quality degradation flag 49B is turned off.

[0075] The status display unit 50 displays the communication status of the repeater 4 by selectively displaying multiple colors. In this embodiment, the display colors of the status display unit 50 that indicate the communication status of the repeater 4 are green, yellow, and red. When wireless communication between the repeater 4 and the communication device is performed at high strength (when the first communication quality degradation flag 49A and the second communication quality degradation flag 49B are off), the display color is green. When wireless communication between the repeater 4 and the communication device is performed but the communication strength is low (when the first communication quality degradation flag 49A or the second communication quality degradation flag 49B is on), the display color is yellow. When wireless communication between the repeater 4 and the communication device is not performed, the display color is red.

[0076] The control unit 43 has multiple control modes. The multiple control modes include a repeater pairing mode, a relay communication mode, a second receiver pairing mode, and a second transmitter pairing mode. The second receiver pairing mode of the repeater 4 is a mode equivalent to the second receiver pairing mode of the receiver 2. The second transmitter pairing mode of the repeater 4 is a mode equivalent to the second receiver pairing mode of the transmitter 3. When the power is on, the repeater 4 is in one of these four control modes.

[0077] The repeater 4 is equipped with a changeover switch (not shown). When this changeover switch is in the on state, the function of the second communication unit 42B is enabled. On the other hand, when the changeover switch is in the off state, the function of the second communication unit 42B is disabled, and the control unit 43 cannot send wireless data to other registered communication devices. In this state, the repeater 4 only performs the receiving function.

[0078] The repeater 4 and the receiver 2 may be configured by the same type of communication device. In this case, by setting the changeover switch to the OFF state, this communication device functions as the receiver 2. By setting the changeover switch to the ON state, this communication device functions as the repeater 4.

[0079] 3 is a block diagram showing the contents stored in the information memory 24 of the receiver 2. The information memory 24 of the receiver 2 has nine storage areas formed therein for storing connection information of the receiver 2. These nine storage areas are referred to as area E11, area E12, area E13, area E14, area E15, area E16, area E17, area E18, and area E19, respectively.

[0080] Area E11 stores address information (receiving device address information) of the receiver 2 (own device). Area E12 stores a group ID (group identification information) assigned to the receiver 2 (own device). Area E13 stores the communication type of the receiver 2 (own device), and in this case, "reception" indicating the receiver 2 is stored as the communication type. Area E14 stores address information (destination transmitter address information) of a transmitter that should wirelessly communicate with the receiver 2 (a transmitter (transmitter 3 or repeater 4) registered as a connection destination with the receiver 2). Area E15 stores address information of a repeater (repeater 4) that should wirelessly communicate with the receiver 2.

[0081] Area E16 temporarily stores address information of communication devices detected by the search. Area E16 is a temporary storage area for temporarily storing information, and no information is stored in area E16 during wireless communication between the receiver 2 and the transmitter 3, or during wireless communication between the receiver 2, the transmitter 3, and the repeater 4.

[0082] Areas E17 to E19 may be blank areas in which no information is stored.

[0083] In the initial state of the receiver 2, information is stored in areas E11 to E13 of the information memory 24, but no information is stored in areas E14 to E19 of the information memory 24. The control unit 23 is also capable of rewriting (adding, changing, deleting, etc.) the information in areas E14 to E19. Turning the power off to the receiver 2 does not clear the information stored in areas E14 to E19. By performing a predetermined clear operation, for example, by turning the power on to the receiver 2 while operating the clear switch 28, the information stored in areas E14 to E19 is cleared.

[0084] 4 is a block diagram showing the contents stored in the information memory 34 of the transmitter 3. The information memory 34 of the transmitter 3 has nine storage areas formed therein for storing connection information of the transmitter 3. These nine storage areas are referred to as area E21, area E22, area E23, area E24, area E25, area E26, area E27, area E28, and area E29, respectively.

[0085] Area E21 stores address information (transmitter address information) of the transmitter 3 (own device). Area E22 stores a group ID assigned to the transmitter 3 (own device). Area E23 stores the communication type of the transmitter 3 (own device), and in this case, "transmission" indicating the transmitter 3 is stored as the communication type. Area E24 stores address information (destination receiver address information) of a receiving device that should communicate wirelessly with the transmitter 3 (a receiving device (receiver 2 or repeater 4) that has been registered as a connection destination with the transmitter 3). Area E25 stores address information of a repeater (repeater 4) that should communicate wirelessly with the transmitter 3.

[0086] Area E26 temporarily stores address information of communication devices detected by the search. Area E26 is a temporary storage area for temporarily storing information, and no information is stored in area E26 during wireless communication between the receiver 2 and the transmitter 3, or during wireless communication between the receiver 2, the transmitter 3, and the repeater 4.

[0087] Areas E27 to E29 may be blank areas in which no information is stored.

[0088] In the initial state of the transmitter 3, information is stored in areas E21 to E23 of the information memory 34, but no information is stored in areas E24 to E29 of the information memory 34. The control unit 33 is also capable of rewriting (adding, changing, deleting, etc.) the information in areas E24 to E29. Turning off the power to the transmitter 3 does not clear the information stored in areas E24 to E29. The information stored in areas E24 to E29 is cleared by a predetermined clearing operation, for example, by turning on the power to the transmitter 3 while operating the clear switch 38.

[0089] 5 is a block diagram showing the contents stored in the information memory 44 of the repeater 4. The information memory 44 of the repeater 4 has nine memory areas formed therein for storing the connection information of the repeater 4. These nine memory areas are referred to as area E31, area E32, area E33, area E34, area E35, area E36, area E37, area E38, and area E39, respectively.

[0090] Area E31 stores the address information of the repeater 4 (own device). Area E32 stores the group ID assigned to the repeater 4 (own device). Area E33 stores the communication type of the repeater 4 (own device). In this case, "relay" is stored, indicating that it is a repeater 4. The communication type of the repeater 4 is one of three: "relay," "relay reception," and "relay transmission." The communication type of the repeater 4 is "relay" in the initial state. When the repeater 4 is in the second repeater reception mode, the communication type of the repeater 4 is "relay reception." When the repeater 4 is in the second repeater transmission mode, the communication type of the repeater 4 is "relay transmission." When the repeater 4 is in any other mode, the communication type of the repeater 4 is "relay." Areas E34 and E35 store the address information of the two communication devices (transmitting device and receiving device) to which the repeater 4 is connected, respectively. Area E34 stores address information of a transmitting device (transmitter 3 or repeater 4) that should communicate wirelessly with repeater 4, and area E35 stores address information of a receiving device (receiver 2 or repeater 4) that should communicate wirelessly with repeater 4.

[0091] Area E36 provisionally stores address information of a communication device detected by a search (a search in the second repeater pairing process (step S142 in FIG. 16) described below). Area E37 provisionally stores address information of a communication device that has been registered as a connection destination with the communication device detected by the search in the second repeater pairing process. If this communication device is a transmitting device, the communication device that has been registered as a connection destination with this communication device is a receiving device (receiver 2 or repeater 4).

[0092] Area E38 temporarily stores address information of a communication device detected by a search (a search in the first repeater pairing process (step S112 in FIG. 14) described later). Area E39 temporarily stores address information of a communication device that has been registered as a connection destination with the communication device detected by the search in the first repeater pairing process. If this communication device is a receiving device (receiver or repeater receiver), the communication device that has been registered as a connection destination with this communication device is a transmitting device (transmitter 3 or repeater 4). Areas E36 to E39 are temporary storage areas for temporarily storing information. During wireless communication between the receiver 2, transmitter 3, and repeater 4, no information is stored in areas E36 to E39.

[0093] In the initial state of the repeater 4, information is stored in areas E31 to E33 of the information memory 44, but no information is stored in areas E34 to E39 of the information memory 44. The control unit 43 is also capable of rewriting (adding, changing, deleting, etc.) the information in areas E35 to E39. Turning the power off to the repeater 4 does not clear the information stored in areas E34 to E39. The information stored in areas E34 to E39 is cleared by a predetermined clearing operation, for example, by turning the power on to the repeater 4 while operating the clear switch 48.

[0094] The group ID is identification information assigned to the receiver 2, repeater 4, and transmitter 3. The same group ID is assigned in advance to the receiver 2, repeater 4, and transmitter 3 that are to communicate wirelessly. In this embodiment, the same group ID is not assigned to the receiver 2, repeater 4, and transmitter 3 that are not intended to communicate wirelessly. Specifically, for example, if a wireless communication system 1 from a certain device vendor has a device type of "TYPE:AAA," different group IDs such as "AAA-G1," "AAA-G2," and "AAA-G3" are assigned to each group of receivers 2, repeaters 4, and transmitters 3 that are to communicate wirelessly with each other for this device type. "AAA-G1," "AAA-G2," and "AAA-G3" are group IDs that are different from one another.

[0095] The communication type is identification information assigned to each type of communication device. The five communication types ("receive", "transmit", "relay", "relay receive", and "relay transmit") may be stored in areas E13, E23, and E33 of the information memories 24, 34, and 44 in the form of numbers, symbols, codes, etc.

[0096] 1A, a case will be described in which wireless communication between a receiver 2 and a transmitter 3 is relayed by a single repeater 4. A single repeater 4 is placed as a relay device on the path between the receiver 2 and the transmitter 3, and wireless communication is performed by the receiver 2, the single repeater 4, and the transmitter 3.

[0097] Fig. 6 is a flow chart showing the procedure for starting relay communication between the receiver 2 and the transmitter 3 by one repeater 4. Fig. 7 is a diagram for explaining receiver-transmitter pairing (step S2 in Fig. 6). Fig. 8 is a diagram for explaining receiving device-repeater-transmitting device pairing (step S5 in Fig. 6).

[0098] The operator brings the receiver 2 and transmitter 3, which have been assigned the same group ID, close enough to each other so that they can communicate wirelessly (step S1 in FIG. 6), and registers the receiver 2 and transmitter 3, which are to communicate wirelessly, as wireless communication destinations (step S2 in FIG. 6). This registration is performed using pairing. When the receiver 2 and transmitter 3 are powered on, if the transmitting device and receiving device to communicate wirelessly are not registered, the receiver 2 and transmitter 3 enter the first receiver pairing mode and the first transmitter pairing mode, respectively. As shown in FIG. 7, while the receiver 2 and transmitter 3 are in the first receiver pairing mode and the first transmitter pairing mode, respectively, connection information is transmitted and received between the receiver 2 and transmitter 3 (pairing) (step S2 in FIG. 6: receiver-transmitter pairing). However, the condition for exchanging connection information is that the group IDs match.

[0099] Specifically, when the power switch 27 of the receiver 2 is operated to turn on the power of the receiver 2, if no address information is stored in area E14 (see FIG. 3) of the information memory 24 of the receiver 2, i.e., if a transmitting device to be wirelessly communicated with is not registered in the receiver 2, the receiver 2 enters the first receiver pairing mode. Also, when the power switch 37 of the transmitter 3 is operated to turn on the power of the transmitter 3, if no address information is stored in area E24 (see FIG. 4) of the information memory 34 of the transmitter 3, i.e., if a receiving device to be wirelessly communicated with is not registered in the transmitter 3, the transmitter 3 enters the first transmitter pairing mode. On the other hand, if a transmitting device to be wirelessly communicated with has already been registered in the receiver 2, the receiver 2 enters the wireless communication mode and starts wireless communication with the registered transmitting device (transmitter or repeater). Similarly, if a receiving device to be wirelessly communicated with has already been registered in the transmitter 3, the transmitter 3 enters the wireless communication mode and starts wireless communication with the registered receiving device (receiver or repeater).

[0100] Through receiver-transmitter pairing, the receiver 2 and the transmitter 3 are registered with each other as communicators that should communicate wirelessly. After that, the receiver 2 and the transmitter 3 transition from the first receiver pairing mode and the first transmitter pairing mode, respectively, to the wireless communication mode. This starts wireless communication between the receiver 2 and the transmitter 3.

[0101] After the start of wireless communication, the worker separates the transmitter 3 from the receiver 2 (step S3 in FIG. 6). Then, when the quality of wireless communication between the receiver 2 and the transmitter 3 deteriorates due to the separation of the transmitter 3 from the receiver 2, the receiver 2 and the transmitter 3 enter the second receiver pairing mode and the second transmitter pairing mode, respectively. In order to transition both the receiver 2 and the transmitter 3 to the pairing mode, the worker places the transmitter 3 in a position where the quality of wireless communication between the transmitter 3 and the receiver 2 deteriorates.

[0102] The worker also places a repeater 4, which has been assigned the same group ID as the receiver 2 and transmitter 3, in a location along the communication path between the receiver 2 and transmitter 3, where it can communicate well with both the receiver 2 and transmitter 3 (step S4 in FIG. 6).The worker then turns on the power to the repeater 4. When the repeater 4 is turned on, if one or both of the transmitter and transmitter with which it should communicate wirelessly are not registered, the repeater 4 enters repeater pairing mode.

[0103] As shown in FIG. 8, when the receiver 2 and the transmitter 3 are in the second receiver pairing mode and the second transmitter pairing mode, respectively, and the repeater 4 is in the repeater pairing mode, connection information is exchanged (paired) between the receiver 2 and the repeater 4 and between the repeater 4 and the transmitter 3 (step S5 in FIG. 6: receiver-repeater-transmitter pairing). In this case, as shown in FIG. 8, first, connection information is exchanged between the repeater 4 and the transmitter 3, and then connection information is exchanged between the receiver 2 and the repeater 4. However, a condition for exchanging connection information is that the group IDs match. Once the exchange of connection information is completed, the repeater 4 starts relaying wireless communication between the receiver 2 and the transmitter 3. That is, wireless communication is started between the receiver 2, one repeater 4, and the transmitter 3 (step S6 in FIG. 6).

[0104] In the above description, an example was given in which the receiver 2 and transmitter 3 are brought close to each other in the receiver-transmitter pairing, and then the transmitter 3 is moved away from the receiver 2, and then the receiver-repeater-transmitter pairing is performed, but conversely, the transmitter 3 and receiver 2 may be brought close to each other, and then the receiver-transmitter pairing may be performed, and then the receiver 2 may be moved away from the transmitter 3, and then the receiver-repeater-transmitter pairing may be performed. Also, the transmitter 3 and receiver 2 may be brought close to each other, and then the receiver-transmitter pairing may be performed, and then the receiver-repeater-transmitter pairing may be performed, and then the transmitter 3 and receiver 2 may be moved away from each other, and then the receiver-repeater-transmitter pairing may be performed.

[0105] Next, the first receiver pairing mode of the receiver 2 and the first transmitter pairing mode of the transmitter 3 for realizing receiver-transmitter pairing (step S2 in FIG. 6) will be described.

[0106] 9 is a flowchart illustrating the processing flow in the first receiver pairing mode of the receiver 2. During the first receiver pairing mode, the control unit 23 of the receiver 2 searches for a transmitter with which to communicate wirelessly (step S31). If this search detects a communication device (receiver, transmitter, repeater, etc.) in pairing mode within communication range with the receiver 2 (YES in step S32), the control unit 23 of the receiver 2 transmits connection information of the receiver 2 itself to the detected communication device (step S33). The connection information transmitted from the receiver 2 is information stored in areas E11 to E13 of the information memory 24 of the receiver 2, i.e., the address information of the receiver 2 itself, the group ID assigned to the receiver 2 itself, and the communication type of the receiver 2 itself. The receiver 2 transmits "reception" as the communication type.

[0107] The control unit 23 of the receiver 2 receives connection information of the detected communication device from the communication device (step S34). The connection information received by the receiver 2 includes address information of the detected communication device, a group ID assigned to the detected communication device, and a communication type of the communication device detected by the search.

[0108] Then, if the group ID received from the detected communication device matches the group ID assigned to the receiver 2 itself (YES in step S35) and the communication type received from the detected communication device is "transmission" (YES in step S36), the control unit 23 of the receiver 2 stores the address information of the detected communication device in area E14 of the information memory 24 of the receiver 2 (step S37). As a result, the detected communication device is registered in the receiver 2 as a transmitting device that should communicate wirelessly with the receiver 2.

[0109] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the receiver 2 itself (NO in step S35), and if the communication type received from the detected communication device is other than "transmission" (NO in step S36), the control unit 23 of the receiver 2 re-searches for a transmitter with which to communicate wirelessly (step S31).

[0110] 10 is a flowchart illustrating the process flow in the first transmitter pairing mode of the transmitter 3. During the first transmitter pairing mode, the control unit 33 of the transmitter 3 searches for a receiver with which to communicate wirelessly (step S41). If this search detects a communication device (receiver, transmitter, repeater, etc.) in pairing mode within a communication range with the transmitter 3 (YES in step S42), the control unit 33 of the transmitter 3 transmits connection information of the transmitter 3 itself to the detected communication device (step S43). The connection information transmitted from the transmitter 3 is information stored in areas E21 to E23 of the information memory 34 of the transmitter 3, i.e., the address information of the transmitter 3 itself, the group ID assigned to the transmitter 3 itself, and the communication type of the transmitter 3 itself. The transmitter 3 transmits "transmission" as the communication type.

[0111] The control unit 33 of the transmitter 3 receives connection information of the detected communication device from the communication device (step S44). The connection information received by the transmitter 3 includes address information of the communication device detected by the search, a group ID assigned to the communication device detected by the search, and a communication type of the communication device detected by the search.

[0112] Then, if the group ID received from the detected communication device matches the group ID assigned to the transmitter 3 itself (YES in step S45) and the communication type received from the detected communication device is "reception" (YES in step S46), the control unit 33 of the transmitter 3 stores the address information of the detected communication device in area E24 of the information memory 34 of the transmitter 3 (step S47). As a result, the detected communication device is registered in the transmitter 3 as a receiver with which to communicate wirelessly.

[0113] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the transmitter 3 itself (NO in step S45), and if the communication type received from the detected communication device is other than "receive" (NO in step S46), the control unit 33 of the transmitter 3 re-searches for a receiver with which to communicate wirelessly (step S41).

[0114] As shown in Fig. 7, when a receiver 2 and a transmitter 3 with the same group ID, which are located in positions where they can communicate with each other, enter the first receiver pairing mode and the first transmitter pairing mode, respectively, the receiver 2 and the transmitter 3 detect each other. Then, information stored in areas E11 to E13 of the information memory 24 of the receiver 2 and information stored in areas E21 to E23 of the information memory 34 of the transmitter 3 are transmitted and received to each other (steps S33 and S34 in Fig. 9, steps S43 and S44 in Fig. 10). Area E14 of the information memory 24 of the receiver 2 stores address information of the transmitter 3 as address information of a transmitting device that should wirelessly communicate with the receiver 2, and the address information of the receiver 2 is stored in area E24 of the information memory 34 of the transmitter 3.

[0115] As a result, the receiver 2 and the transmitter 3 are registered with each other as communication devices that should communicate wirelessly. After the first receiver pairing mode and the first transmitter pairing mode end, the receiver 2 and the transmitter 3 transition to wireless communication mode. The receiver 2 and the transmitter 3 communicate with each other based on the address information of the transmitter 3 and the receiver 2 acquired in the first receiver pairing mode and the first transmitter pairing mode. As a result, wireless communication between the receiver 2 and the transmitter 3 begins.

[0116] Next, the receiver-repeater-transmitter pairing (step S5 in FIG. 6) will be described. As described above, after the receiver-transmitter pairing (step S2 in FIG. 6), the receiver 2 and the transmitter 3 are separated from each other (step S3 in FIG. 6), and the quality of the wireless communication between the receiver 2 and the transmitter 3 is reduced. When the quality of the wireless communication between the receiver 2 and the transmitter 3 is reduced while the receiver 2 and the transmitter 3 are registered with each other as communicators to communicate wirelessly, the first communication quality reduction flag 29A of the control unit 23 of the receiver 2 is turned on, and the communication quality reduction flag 39A of the control unit 33 of the transmitter 3 is turned on. When the first communication quality reduction flag 29A of the receiver 2 is turned on, the receiver 2 enters a second receiver pairing mode. When the communication quality reduction flag 39A of the transmitter 3 is turned on, the transmitter 3 enters a second transmitter pairing mode.

[0117] The worker also places the repeater 4 as a relay device in a position where it can communicate well with both the receiver 2 and the transmitter 3 (step S4 in FIG. 6), and turns on the power to the repeater 4. FIG. 11 is a flow chart illustrating the process that occurs after the repeater 4 is turned on. FIG. 12 is a block diagram illustrating the process flow in the repeater pairing mode of the repeater 4.

[0118] The power switch 47 of the repeater 4 is operated to turn on the power of the repeater 4 (step S71 in FIG. 11). When the power of the repeater 4 is turned on, if one or both of the receiving device and the transmitting device that are to communicate wirelessly with the repeater 4 are not registered (NO in step S72 in FIG. 11), the repeater 4 enters repeater pairing mode (step S73 in FIG. 11). Specifically, if address information is not stored in area E34 and / or area E35 of the information memory 44 of the repeater 4, the repeater 4 enters repeater pairing mode.

[0119] On the other hand, if the receiving device and transmitting device that should communicate wirelessly with the repeater 4 are registered in the repeater 4 (YES in step S72), the repeater 4 enters relay communication mode (step S74). Then, the repeater 4 starts relay communication with the registered receiving device and transmitting device.

[0120] During the repeater pairing mode, the control unit 43 of the repeater 4 executes a first repeater pairing process (step S81 in FIG. 12), a second repeater pairing process (step S82 in FIG. 12), and a determination and registration process (step S83 in FIG. 12). The first repeater pairing process (S81) is a process for transmitting and receiving information with a transmitting device (transmitter or relay transmitter) in the second transmitter pairing mode. The second repeater pairing process (S82) is a process for transmitting and receiving information with a receiving device (receiver or relay receiver) in the second receiver pairing mode. The determination and registration process (S83) is a process for determining whether to end the repeater pairing mode and transition to the relay communication mode. The first repeater pairing process (S81) and the second repeater pairing process (S82) may be executed in any order, or may be executed in parallel.

[0121] After the repeater pairing mode ends, the repeater 4 enters the relay communication mode (step S74 in FIG. 11). The repeater 4 relays wireless communication with the receiver 2 and transmitter 3 that are paired in the repeater pairing mode, and wireless communication is initiated between the receiver 2, the repeater 4, and the transmitter 3.

[0122] First, we will explain the second transmitter pairing mode of the transmitter 3 and the 12th repeater pairing process of the repeater 4 (step S82 in Figure 12) to realize the receiving device-repeater-transmitting device pairing (step S5 in Figure 6).

[0123] 13A and 13B are flowcharts illustrating the flow of processing in the second transmitter pairing mode of the transmitter 3. During the second transmitter pairing mode, the control unit 33 of the transmitter 3 searches for a relay (relay device) with which to communicate wirelessly (first relay device search step, step S121 in FIG. 13A). In this case, if a communication device (receiver, transmitter, or relay device) in pairing mode is present within a communication range with the transmitter 3 (YES in step S122 in FIG. 13A), the transmitter 3 detects this communication device and transmits its own connection information (transmitter device connection information) to the communication device (step S123 in FIG. 13A). The connection information transmitted from the transmitter 3 is information stored in areas E21 to E24 of the information memory 34 of the transmitter 3, i.e., the address information of the transmitter 3 itself, the group ID assigned to the transmitter 3 itself, the communication type of the transmitter 3 itself, and the address information of receiving devices registered with the transmitter 3 as connection destinations. The transmitter 3 sends "transmission" as the communication type.

[0124] The control unit 33 of the transmitter 3 receives connection information of the detected communication device from the communication device (step S124 in FIG. 13A). The connection information received by the transmitter 3 includes address information of the detected communication device, a group ID assigned to the communication device, and the communication type of the communication device.

[0125] Then, if the group ID received from the detected communication device matches the group ID assigned to the transmitter 3 itself (YES in step S125 of FIG. 13A) and the communication type received from that communication device is "relay" (YES in step S126 of FIG. 13A), the control unit 33 of the transmitter 3 provisionally stores the address information of that communication device in area E26 of the information memory 34 of the transmitter 3. As a result, the detected communication device is provisionally registered in the transmitter 3 as a relay device with which to communicate wirelessly (step S127 of FIG. 13A).

[0126] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the transmitter 3 itself (NO in step S125 of FIG. 13A), and if the communication type received from the detected communication device is other than "relay" (NO in step S126 of FIG. 13A), the control unit 33 of the transmitter 3 re-searches for the relay device 4 to which to wirelessly connect (step S121 of FIG. 13A). Subsequent processing in the second transmitter pairing mode will be described later.

[0127] FIG. 14 is a flowchart illustrating the flow of the first repeater pairing process (step S81 in FIG. 12) of the repeater 4. During the first repeater pairing mode, the control unit 43 of the repeater 4 searches for a transmitting device to be wirelessly connected (transmitting device search step, step S141). When this search detects a communication device (receiver, transmitter, or repeater) in pairing mode within a communication range with the repeater 4 (YES in step S142), the control unit 43 of the repeater 4 transmits its own connection information (information stored in areas E31 to E33) to that communication device (step S143). The repeater 4 transmits "relay" as the communication type.

[0128] The control unit 43 of the repeater 4 receives connection information of the detected communication device from the detected communication device (step S144). The connection information received by the repeater 4 is the same as the connection information received by the control unit 43 in step S114 of FIG. 16, which will be described next.

[0129] If the group ID received from the detected communication device matches the group ID assigned to the repeater 4 itself (YES in step S145) and the communication type received from that communication device is "transmission" or "relay transmission" (YES in step S146), the control unit 43 of the repeater 4 provisionally registers that communication device in the repeater 4 as a transmitting device with which to communicate wirelessly (step S147). Specifically, address information of the detected communication device and address information of communication devices already registered as connection destinations with that communication device are stored in areas E36 and E37 of the information memory 44 of the repeater 4, respectively. This completes the first repeater pairing process (step S81 in FIG. 12).

[0130] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the repeater 4 itself (NO in step S145), and if the communication type received from the detected communication device is other than "transmission" or "relay transmission" (NO in step S146), the control unit 43 of the repeater 4 re-searches for the transmitting device with which to communicate wirelessly without storing the address information in the information memory 44 (step S141).

[0131] Next, we will explain the second receiver pairing mode of the receiver 2 and the second repeater pairing process of the repeater 4 (step S82 in Figure 12) to realize the receiving device-repeater-transmitting device pairing (step S5 in Figure 6).

[0132] 15A and 15B are flowcharts illustrating the processing flow in the second receiver pairing mode of the receiver 2. During the second receiver pairing mode, the control unit 23 of the receiver 2 searches for a repeater (relay device) with which to communicate wirelessly (second repeater search step, step S91 in FIG. 15A). In this case, if a communication device (receiver, transmitter, or repeater) in pairing mode is within communication range with the receiver 2 (YES in step S92 in FIG. 15A), the receiver 2 detects this communication device through a search. Upon detecting a communication device in pairing mode through a search, the control unit 23 of the receiver 2 transmits connection information of the receiver 2 itself (receiving device connection information) to the communication device detected through the search (step S93 in FIG. 15A). The connection information transmitted from the receiver 2 is information stored in areas E11 to E14 of the information memory 24 of the receiver 2, i.e., the address information of the receiver 2 itself, the group ID assigned to the receiver 2 itself, the communication type of the receiver 2 itself, and the address information of a transmitting device registered as a connection destination for the receiver 2. At this time, the receiver 2 sends "reception" as the communication type.

[0133] The control unit 23 of the receiver 2 receives connection information of the detected communication device from the communication device (step S94 in FIG. 15A). The connection information received by the receiver 2 includes address information of the detected communication device, a group ID assigned to the detected communication device, and a communication type of the detected communication device.

[0134] Then, if the group ID received from the detected communication device matches the group ID assigned to the receiver 2 itself (YES in step S95 of FIG. 15A) and the communication type received from the detected communication device is "relay" (YES in step S96 of FIG. 15A), the control unit 23 of the receiver 2 provisionally stores the address information of the detected communication device in area E16 of the information memory 24 of the receiver 2. As a result, the detected communication device is provisionally registered in the receiver 2 as a relay device with which to communicate wirelessly (step S97 of FIG. 15A).

[0135] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the receiver 2 itself (NO in step S95 of FIG. 15A), or if the communication type received from the detected communication device is other than "relay" (NO in step S96 of FIG. 15A), the control unit 23 of the receiver 2 re-searches for the relay device 4 to which it should wirelessly connect (step S91 of FIG. 15A). Subsequent processing in the second receiver pairing mode will be described later.

[0136] FIG. 16 is a flowchart illustrating the second repeater pairing process (step S82 in FIG. 12) of the repeater 4. During repeater pairing mode, the control unit 43 of the repeater 4 searches for a receiving device (receiver or relay receiver) with which to communicate wirelessly (receiving device search step, step S111). In this case, if a communication device (receiver, transmitter, or repeater) in pairing mode is within communication range with the repeater 4 (YES in step S112), the repeater 4 detects this communication device. Upon detecting a communication device in pairing mode, the control unit 43 of the repeater 4 transmits its own connection information to the detected communication device (step S113). The connection information transmitted from the repeater 4 includes information stored in areas E31 to E33 of the information memory 44 of the repeater 4, i.e., its own address information, the group ID assigned to the repeater 4, and its own communication type. The repeater 4 transmits "relay" as the communication type.

[0137] The control unit 43 of the repeater 4 receives connection information of the detected communication device from the communication device (step S114). The connection information received by the repeater 4 includes address information of the detected communication device, a group ID assigned to the communication device, a communication type of the communication device, and address information of communication devices registered as connection destinations to the communication device.

[0138] If the group ID received from the detected communication device matches the group ID assigned to the repeater 4 itself (YES in step S115) and the communication type received from the communication device is "receive" or "relayed receive" (YES in step S116), the control unit 43 of the repeater 4 provisionally registers the communication device in the repeater 4 as a receiving device with which to communicate wirelessly (step S117). Specifically, the address information of the communication device and the address information of communication devices already registered as connection destinations for the communication device are stored in areas E38 and E39 of the information memory 44 of the repeater 4, respectively. This completes the second repeater pairing process (step S82 in FIG. 12).

[0139] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the repeater 4 itself (NO in step S115), and if the communication type received from the detected communication device is other than "receive" or "relayed receive" (NO in step S116), the control unit 43 of the repeater 4 re-searches for a receiving device with which to communicate wirelessly without storing address information in the information memory 44 (step S111).

[0140] Next, a description will be given of the determination and registration process (step S83 in FIG. 12) executed in the relay pairing mode of the relay 4. FIG. 17 is a flowchart for explaining the flow of the determination and registration process (step S83 in FIG. 12) of the relay 4.

[0141] In the determination and registration process, the control unit 43 of the repeater 4 checks whether the address information of the communication device (receiving device) received from the communication device (receiving device) in step S144 (see FIG. 14) of the first repeater pairing process matches the address information of the communication device (receiving device) registered as a connection destination in the communication device (transmitting device) received from the communication device (receiving device) in step S114 (see FIG. 16) of the second repeater pairing process (verifies; step S151). Specifically, it checks whether the address information stored in areas E38 and E37 of the information memory 44 is the same (determination step).

[0142] In addition, in the determination and registration process, the control unit 43 of the repeater 4 checks whether the address information of the communication device (transmitting device) received from the communication device (transmitting device) in step S114 (see FIG. 16) of the second repeater pairing process matches (compares) the address information of the communication device (transmitting device) registered as a connection destination in the communication device (receiving device) received from the communication device (receiving device) in step S144 (see FIG. 14) of the first repeater pairing process. Specifically, it checks whether the address information stored in areas E36 and E39 of the information memory 44 is the same (determination step).

[0143] If these two sets of address information match (YES in step S151 and YES in step S152), the control unit 43 of the repeater 4 switches the registration of the communication device detected by the search to the repeater 4 from provisional registration to formal registration (steps S153 and S154). Specifically, the control unit 43 of the repeater 4 stores the address information of the communication device (receiving device) stored in area E38 in area E35. The information stored in areas E38 and E39 may be cleared. As a result, the communication device that was provisionally registered in the repeater 4 is formally registered in the repeater 4 as a receiving device with which to communicate wirelessly (step S153). Furthermore, the control unit 43 of the repeater 4 stores the address information of the communication device (transmitting device) stored in area E36 in area E34. The information stored in areas E36 and E37 may be cleared. As a result, the communication device that has been provisionally registered in the repeater 4 is officially registered in the repeater 4 as a transmitting device with which to perform wireless communication (step S154).

[0144] Then, the control unit 43 of the repeater 4 transmits a connection success notification to both the detected communication device (receiving device) and the communication device (transmitting device) (step S155). After that, the determination and registration process (step S83 in FIG. 12) ends. This ends the repeater pairing mode of the repeater 4.

[0145] On the other hand, if one or both of the two sets of address information combinations do not match (NO in step S151 or NO in step S152), the control unit 43 of the repeater 4 clears the information stored in areas E36 to E39 (step S156) and sends a connection failure notification to both the detected communication device (receiving device) and communication device (transmitting device) as a connection notification (step S157). This ends the determination and registration process (step S83 in FIG. 12).

[0146] Next, the processing performed by the receiver 2 that has received the connection notification will be described with reference to Fig. 15B. If the connection notification received from the detected repeater 4 is a connection failure notification (YES in step S98 of Fig. 15B, NO in step S99), the control unit 23 of the receiver 2 clears the information stored in area E16 of the information memory 24 and deletes the provisional registration of the communication device (repeater) from the receiver 2 (step S100 of Fig. 15B). Thereafter, the control unit 23 of the receiver 2 re-searches for a repeater with which to communicate wirelessly (step S91 of Fig. 15A).

[0147] On the other hand, if the connection notification received from the detected repeater 4 is a successful connection notification (YES in step S98 and YES in step S99 in FIG. 15B), the provisional registration of the communication device (repeater) with the receiver 2 is switched to official registration. Specifically, the control unit 23 of the receiver 2 stores the address information of the repeater 4 stored in area E16 in area E15. The information stored in area E16 may be cleared. This ends the second receiver pairing mode, and the receiver 2 transitions from the second receiver pairing mode to the wireless communication mode.

[0148] Next, the process performed by the transmitter 3 that has received the connection notification will be described with reference to Fig. 13B. If the connection notification received from the detected repeater 4 is a connection failure notification (YES in step S128 of Fig. 13B, NO in step S129), the control unit 33 of the transmitter 3 clears the information stored in area E26 of the information memory 34 and deletes the provisional registration of the communication device (repeater) from the transmitter 3 (step S130 of Fig. 13B). Thereafter, the control unit 23 of the receiver 2 re-searches for the repeater 4 with which to communicate wirelessly (step S121 of Fig. 13A).

[0149] On the other hand, if the connection notification received from the detected repeater 4 is a successful connection notification (YES in step S128 and YES in step S129 in FIG. 13B), the provisional registration of the communication device (repeater) with the receiver 2 is switched to official registration. Specifically, the control unit 33 of the transmitter 3 stores the address information of the repeater 4 stored in area E26 in area E25. The information stored in area E26 may be cleared. This ends the second transmitter pairing mode, and the transmitter 3 transitions from the second transmitter pairing mode to the wireless communication mode.

[0150] As shown in FIG. 8, when the receiver 2 and the repeater 4, which are located in positions where they can communicate with each other, enter the second receiver pairing mode and the repeater pairing mode, respectively, the receiver 2 and the repeater 4 detect each other. The same group ID is assigned to the receiver 2 and the repeater 4. The type information of the receiver 2 and the repeater 4 is "receive" and "relay," respectively. Then, the information stored in areas E11 to E14 of the information memory 24 of the receiver 2 and the information stored in areas E31 to E33 of the information memory 44 of the repeater 4 are transmitted and received to each other (steps S93 and S94 in FIG. 15A, steps S113 and S114 in FIG. 16).

[0151] 8, when the repeater 4 and the transmitter 3, which are located in positions where they can communicate with each other, enter the repeater pairing mode and the second transmitter pairing mode, respectively, the repeater 4 and the transmitter 3 detect each other. The same group ID is assigned to the repeater 4 and the transmitter 3. The type information of the repeater 4 and the transmitter 3 is "relay" and "transmission," respectively. Then, the information stored in areas E31 to E33 of the information memory 44 of the repeater 4 and the information stored in areas E21 to E24 of the information memory 34 of the transmitter 3 are transmitted and received to and from each other (steps S123 and S124 in FIG. 13A, steps S143 and S144 in FIG. 14).

[0152] Then, when the address information of the communication device (receiving device) received from the detected communication device (receiving device) matches the address information of the communication device (receiving device) already registered as a connection destination for the communication device (transmitting device) received from the detected communication device (transmitting device), and when the address information of the communication device (transmitting device) received from the detected communication device (transmitting device) matches the address information of the communication device (transmitting device) already registered as a connection destination for the communication device (receiving device), the receiver 2 and the repeater 4 are registered with each other as communication devices that should communicate wirelessly, and the repeater 4 and the transmitter 3 are registered with each other as communication devices that should communicate wirelessly (steps S151 to S154 in Figure 17).

[0153] After the second receiver pairing mode and the second transmitter pairing mode are terminated, the receiver 2 and the transmitter 3 each transition to wireless communication mode. Furthermore, after the repeater pairing mode is terminated, the repeater 4 transitions to relayed communication mode. The receiver 2, the repeater 4, and the transmitter 3 begin communication with each other based on the address information of the communication devices with which to communicate wirelessly, acquired in the second receiver pairing mode, the repeater pairing mode, and the second transmitter pairing mode. This initiates wireless communication between the receiver 2, the repeater 4, and the transmitter 3.

[0154] If two communication devices (a receiving device and a transmitting device) have registered each other as wireless communication destinations, the address information of the communication device received from one communication device by a relay device that relays wireless communication between them will match the address information of the communication device registered as a connection destination received from the other communication device.Similarly, the address information of the communication device received from the other communication device will match the address information of the communication device registered as a connection destination received from one communication device.

[0155] Since the condition for determining whether to switch to the relayed communication mode is a match between two pairs of address information, rather than just one pair, it is possible to doubly ensure that the two communication devices (the receiving device and the transmitting device) have each other registered as wireless communication destinations in advance, thereby avoiding relay errors such as the relay device 4 relaying a transmitting device and a receiving device that are not intended to communicate wirelessly.

[0156] The same group ID is assigned in advance to the receiver 2, transmitter 3, and repeater 4 that are to communicate wirelessly. In repeater pairing mode, if the group IDs received from two communication devices detected by search match the group ID assigned to the repeater 4, the repeater 4 transitions to relayed communication mode. This prevents wireless communication from being initiated by a receiver 2, transmitter 3, or repeater 4 that is not intended to communicate wirelessly.

[0157] In this embodiment, a match between one pair of address information may be used as a criterion for determining whether to transition to the relay communication mode. Specifically, the relay device 4 may transition to the relay communication mode when only one of the two sets of address information in steps S151 and S152 in FIG. 17 matches. Even when only one pair of address information matches, relay errors can be almost certainly avoided.

[0158] However, when the distance between the alarm device 12 and the production device 11 is long or when there are obstacles (buildings or walls) between the alarm device 12 and the production device 11, simply placing a single repeater 4 between the receiver 2 and the transmitter 3 may not ensure good wireless communication between the receiver 2, the transmitter 3, and the repeater 4. To address this issue, as shown in FIG. 1B , multiple repeaters 4 are used to relay the wireless communication between the receiver 2 and the transmitter 3. To relay the wireless communication between the receiver 2 and the transmitter 3 using multiple repeaters 4, the number of repeaters 4 placed on the path between the receiver 2 and the transmitter 3 must be increased by one. One possible method for increasing the number of repeaters 4 is to place a new repeater 4 between the receiver 2 and the repeater 4 or between the repeater 4 and the transmitter 3 after wireless communication between the receiver 2, the repeater 4, and the transmitter 3 is established by receiver-repeater-transmitter pairing (step S5 in FIG. 6 ).

[0159] Fig. 18 is a flow chart showing the procedure when another repeater 4 (repeater 4D) is newly placed on the path between the repeater 4 and the transmitter 3. Fig. 19 is a diagram for explaining the receiving device-repeater-transmitting device pairing (step S163 in Fig. 18) when another repeater 4 is newly placed on the path between the repeater 4 and the transmitter 3.

[0160] After wireless communication between the receiver 2, the repeater 4, and the transmitter 3 is established through the receiver-repeater-transmitter pairing (step S5 in FIG. 6), the worker separates the transmitter 3 from the receiver 2 and the repeater 4 (step S161 in FIG. 18). By separating the transmitter 3 from the repeater 4, the quality of the wireless communication between the repeater 4 and the transmitter 3 decreases. The transmitter 3, whose wireless communication quality with the repeater 4 has decreased, transitions to a second transmitter pairing mode. Meanwhile, the repeater 4, whose wireless communication quality with the transmitter 3 has decreased, transitions to a second receiver pairing mode. The worker places the transmitter 3 in a position where the quality of the wireless communication with the repeater 4 decreases, causing the transmitter 3 and the repeater 4 to transition to a second transmitter pairing mode and a second receiver pairing mode, respectively.

[0161] Then, the worker newly places another repeater 4 between the repeater 4 and the transmitter 3 (step S162 in FIG. 18). Hereinafter, the newly placed repeater 4 may be referred to as "repeater 4D." The repeater 4D, which is a relay device, relays wireless communication between the repeater 4 and the transmitter 3. Hereinafter, the repeater 4 with which wireless communication is performed (i.e., the repeater 4 that has transitioned to the second receiver pairing mode) as seen from the repeater 4D may be referred to as "relay receiver 4E."

[0162] The repeater 4D is the same type of repeater 4 as the repeater receiver (receiving device) 4E. The repeater 4D is assigned the same group ID as the repeater receiver 4E. It goes without saying that the address information of the repeater 4D is different from the address information of the repeater receiver 4E.

[0163] The repeater 4D is placed in a position where it can communicate well with both the relay receiver 4E and the transmitter 3. Then, the worker turns on the power to the repeater 4D. When the power to the repeater 4D is turned on, if one or both of the transmitting device to be wirelessly communicated with and the transmitting device to be wirelessly communicated with are not registered in the repeater 4D, the repeater 4D enters repeater pairing mode.

[0164] As shown in FIG. 19, when the relay receiver 4E and the transmitter 3 are in the second receiver pairing mode and the second transmitter pairing mode, respectively, and the relay 4D is in the repeater pairing mode, connection information is transmitted and received between the relay receiver 4E and the repeater 4D and between the repeater 4D and the transmitter 3 (step S163 in FIG. 18: receiving device-repeater-transmitter pairing). In this case, as shown in FIG. 19, first, connection information is transmitted and received between the repeater 4E and the transmitter 3, and then connection information is transmitted and received between the relay receiver 4E and the repeater 4D. As a result, the repeater 4D is registered with the relay receiver 4E and the transmitter 3 as a repeater with which to communicate wirelessly. Furthermore, the relay receiver 4E and the transmitter 3 are registered with the repeater 4D as a receiving device and a transmitting device with which to communicate wirelessly, respectively. Thereafter, the relay device 4D and the relay receiver 4E return to the relay communication mode, and the transmitter 3 returns to the wireless communication mode, thereby starting wireless communication between the two relay devices 4 and the transmitter 3 (step S164 in FIG. 18).

[0165] Fig. 20 is a flow chart showing the procedure when a repeater 4D is newly placed on the path between the receiver 2 and the repeater 4. Fig. 21 is a diagram for explaining the receiving device-repeater-transmitting device pairing (step S173 in Fig. 20) when a repeater 4D is newly placed on the path between the receiver 2 and the repeater 4.

[0166] After wireless communication between the receiver 2, the repeater 4, and the transmitter 3 is established through the receiver-repeater-transmitter pairing (step S5 in FIG. 6), the worker separates the receiver 2 from the transmitter 3 and the repeater 4 (step S171 in FIG. 20). By separating the receiver 2 from the repeater 4, the quality of the wireless communication between the receiver 2 and the repeater 4 decreases. The receiver 2, whose wireless communication quality with the repeater 4 has decreased, transitions to a second receiver pairing mode. Meanwhile, the repeater 4, whose wireless communication quality with the receiver 2 has decreased, transitions to a second transmitter pairing mode. The worker places the receiver 2 in a position where the quality of the wireless communication with the repeater 4 decreases, causing the receiver 2 and the repeater 4 to transition to a second receiver pairing mode and a second transmitter pairing mode, respectively.

[0167] Then, the worker newly places a repeater 4D between the receiver 2 and the repeater 4 (step S172 in FIG. 20). The repeater 4D relays wireless communication between the receiver 2 and the repeater 4. Hereinafter, the repeater 4 that is the wireless communication destination from the perspective of the repeater 4D (i.e., the repeater 4 that has transitioned to the second transmitter pairing mode) may be referred to as the "relay transmitter 4F."

[0168] The repeater 4D is placed in a position where it can communicate well with both the receiver 2 and the repeater transmitter (transmitting device) 4F. Then, the worker turns on the power to the repeater 4D. When the power to the repeater 4D is turned on, if one or both of the transmitting device with which the repeater 4D is to communicate wirelessly and the transmitting device with which the repeater 4D is to communicate wirelessly are not registered in the repeater 4D, the repeater 4D enters repeater pairing mode.

[0169] As shown in FIG. 21, when the receiver 2 and the relay transmitter 4F are in the second receiver pairing mode and the second transmitter pairing mode, respectively, and the relay 4D is in the relay pairing mode, connection information is transmitted and received between the receiver 2 and the relay 4D and between the relay 4D and the relay transmitter 4F (step S173 in FIG. 20: receiving device-relay-transmitting device pairing). In this case, as shown in FIG. 21, first, connection information is transmitted and received between the relay 4D and the relay transmitter 4F, and then connection information is transmitted and received between the receiver 2 and the relay transmitter 4D. As a result, the relay 4D is registered with the receiver 2 and the relay transmitter 4F as a relay with which to communicate wirelessly. Furthermore, the receiver 2 and the relay transmitter 4F are registered with the relay 4D as a receiving device and a transmitting device with which to communicate wirelessly, respectively. Thereafter, the relay device 4D and the relay transmitter 4F return to the relay communication mode, and the receiver 2 returns to the wireless communication mode, thereby starting wireless communication between the two relay devices 4 and the transmitter 3 (step S174 in FIG. 20).

[0170] FIG. 22 is a flowchart for explaining the transition of the control mode of the repeater 4. In FIG.

[0171] As described above, the control unit 43 has four control modes: the repeater pairing mode, the relay communication mode, the second receiver pairing mode, and the second transmitter pairing mode.

[0172] When the repeater 4 is relaying communication between a receiving device and a transmitting device, if the quality of wireless communication between the repeater 4 and the communication device (receiving device, transmitting device) of the wireless communication destination deteriorates, one or both of the first communication quality deterioration flag 49A and the second communication quality deterioration flag 49B of the control unit 43 of the repeater 4 is turned on (steps S181, S182). Because the repeater 4 has two flags, the first communication quality deterioration flag 49A and the second communication quality deterioration flag 49B, the control unit 43 of the repeater 4 can not only determine that the quality of wireless communication with the communication device (receiving device, transmitting device) of the wireless communication destination deteriorates, but also identify whether the quality deteriorates in the wireless communication with the receiving device or the wireless communication with the transmitting device.

[0173] If the second communication quality degradation flag 49B is on (NO in step S181, YES in step S182), the repeater 4 determines that the quality of the wireless communication with the transmitting device has deteriorated, and transitions to the second receiver pairing mode (step S183). During the second receiver pairing mode of the repeater 4, the communication type of the repeater 4 is "relay reception."

[0174] As described above, the second receiver pairing mode of the repeater 4 is a mode equivalent to the second receiver pairing mode (see FIGS. 13A and 13B) of the receiver 2. During the second receiver pairing mode of the repeater 4, areas E31 to E35 of the information memory 44 are used instead of areas E11 to E15 of the information memory 24 of the receiver 2, respectively.

[0175] On the other hand, if the first communication quality degradation flag 49A is on (YES in step S181), the repeater 4 determines that the quality of wireless communication with the receiving device has deteriorated and transitions to the second transmitter pairing mode (step S185).

[0176] As described above, the second transmitter pairing mode of the repeater 4 is a mode equivalent to the second transmitter pairing mode (see FIGS. 13A and 13B) of the transmitter 3. During the second transmitter pairing mode of the repeater 4, areas E31, E32, E33, E35, and E34 of the information memory 44 of the repeater 4 are used instead of areas E21, E22, E23, E24, and E25 of the information memory 34 of the transmitter 3, respectively.

[0177] In the receiver-repeater-transmitter pairing (see FIG. 19) of the relay receiver 4E, the repeater 4D, and the transmitter 3, the relay receiver 4E transmits and receives connection information to and from the repeater 4D in the repeater pairing mode (step S183). As described above, in the second receiver pairing mode of the repeater 4, areas E31 to E35 of the information memory 44 are used instead of areas E11 to E15 of the information memory 24, respectively. Therefore, the relay receiver 4E transmits information stored in areas E31 to E34 to the repeater 4D and receives information stored in areas E31 to E33 of the information memory 44 of the repeater 4D from the repeater 4D (steps S93 and S94 in FIG. 13A). At this time, the repeater 4D stores the address information stored in areas E31 and E34 of the information memory 44 of the relay receiver 4E in the repeater pairing mode in areas E36 and E37 of the information memory 44 of the repeater 4D, respectively.

[0178] Then, based on these address information, in the relay device 4D's relay device pairing mode determination and registration process (step S83 in FIG. 12), it is determined whether to transition to the relay communication mode (steps S151 and S152 in FIG. 17). If it is determined to transition to the relay communication mode, the relay receiver 4E is registered in the relay device 4D as a receiving device with which to communicate wirelessly. Then, the relay device 4D transitions to the relay communication mode.

[0179] Furthermore, upon receiving the connection success notification from the repeater 4D, the control unit 43 of the relay receiver 4E stores the address information of the repeater 4D in the area E35 of the repeater 4D. As a result, the repeater 4D is registered in the relay receiver 4E as a repeater with which to communicate wirelessly.

[0180] Meanwhile, in the receiver-repeater-transmitter pairing (see FIG. 21) of the receiver 2, the repeater 4D, and the relay transmitter 4F, the relay transmitter 4F transmits and receives connection information to and from the repeater 4D in the repeater pairing mode (step S183). As described above, in the second transmitter pairing mode of the repeater 4, areas E31 to E35 of the information memory 44 are used instead of areas E21 to E25 of the information memory 34, so the relay transmitter 4F transmits the information stored in areas E31 to E35 and area E35 to the repeater 4D and receives the information stored in areas E31 to E33 of the information memory 44 of the repeater 4D from the repeater 4D (steps S123 and S124 of FIG. 13A). At this time, the relay device 4D stores the address information stored in areas E31 and E35 of the information memory 44 of the relay transmitter 4F in the relay device pairing mode in areas E36 and E37 of the information memory 44 of the relay transmitter 4F, respectively.

[0181] Then, based on these address information, in the relay device 4D's relay device pairing mode determination and registration process (step S83 in FIG. 12), it is determined whether to transition to the relay communication mode (steps S151 and S152 in FIG. 17). If it is determined to transition to the relay communication mode, the relay transmitter 4F is registered in the relay device 4D as a transmitting device with which to communicate wirelessly. Then, the relay device 4D transitions to the relay communication mode.

[0182] Furthermore, the control unit 43 of the relay transmitter 4F, which has received a connection success notification from the relay 4D, stores the address information of the relay 4D in the area E35 of the relay 4D. As a result, the relay 4D is registered in the relay transmitter 4F as a relay with which to communicate wirelessly.

[0183] If the placement of only two repeaters 4 between the receiver 2 and the transmitter 3 does not allow for good wireless communication between the receiver 2, the transmitter 3, and the repeater 4, this can be addressed by adding another repeater 4. The number of repeaters 4 placed on the path between the receiver 2 and the transmitter 3 can be increased by the methods shown in Figures 18 and 19 or the methods shown in Figures 20 and 21.

[0184] As described above, according to this embodiment, the worker places the repeater 4 in a position where it can communicate well with both the receiving device (receiver 2 or relay receiver 4E) and the transmitting device (transmitter 3 or relay transmitter 4F) and turns on the power to the repeater 4. Turning on the power to the repeater 4 places the repeater 4 in repeater pairing mode. Connection information including address information of the repeater 4 and address information of the receiving device (receiver 2 or relay receiver 4E) is exchanged between the repeater 4 in repeater pairing mode and the receiving device (receiver 2 or relay receiver 4E) in the second receiver pairing mode. Furthermore, connection information including address information of the repeater 4 and address information of the transmitting device (transmitter 3 or relay transmitter 4F) is exchanged between the repeater 4 in repeater pairing mode and the transmitting device (transmitter 3 or relay transmitter 4F) in the second transmitter pairing mode.

[0185] Then, the control unit 23 of the repeater 4 determines whether to transition from pairing mode to relayed communication mode based on the four pieces of address information received from the receiving device and the transmitting device. When it is determined to transition to relayed communication mode, the repeater 4 and the receiving device (receiver 2 or relay receiver 4E) are registered with each other as communication devices that should communicate wirelessly, and the repeater 4 and the transmitting device (transmitter 3 or relay transmitter 4F) are registered with each other as communication devices that should communicate wirelessly. This allows the repeater 4 to start relaying wireless communication between the receiving device (transmitter 3 or relay transmitter 4F) and the transmitting device (transmitter 3 or relay transmitter 4F).

[0186] As described above, relaying of wireless communication between a receiving device (receiver 2 or relay receiver 4E) and a transmitting device (transmitter 3 or relay transmitter 4F) by the relay device 4 can be started by the simple operation of turning on the power of the relay device 4. Moreover, since the relay device 4 can search for receiving devices, search for transmitting devices, and determine whether to switch to relay communication mode in a single pairing mode, relay communication can be started with a simple operation compared to when registration work is performed in multiple separate steps.

[0187] As described above, the connection information (pairing information, key information) includes address information of the communication device (receiving device) that has been registered as a connection destination with the communication device (transmitting device) detected by the search, and address information of the communication device (transmitting device) that has been registered as a connection destination with the communication device (receiving device) detected by the search. Therefore, when the repeater transitions from repeater pairing mode to relay communication mode, it is guaranteed that the two communication devices (receiving device and transmitting device) detected by the search have pre-registered each other as wireless communication destinations. Therefore, relaying of wireless communication between the receiving device (receiver 2 or relay receiver 4E) and the transmitting device (transmitter 3 or relay transmitter 4F) by the repeater 4 can be started with a simple operation while avoiding relay errors.

[0188] Fig. 23 is a block diagram showing the contents stored in the information memory 24 of the receiver 2 included in the wireless communication system 201 according to the second embodiment of the present invention. Fig. 24 is a diagram for explaining the receiving device-repeater-transmitting device pairing performed in the wireless communication system 201. Figs. 25 and 26 are flowcharts for explaining the processing flow in the second receiver pairing mode of the receiver 2 included in the wireless communication system 201. Figs. 27 and 28 are flowcharts for explaining the flow of the second repeater pairing processing of the repeater 4 included in the wireless communication system 201.

[0189] 23 to 28, components equivalent to those shown in the above-described Figures 1 to 22 are given the same reference numerals as in Figure 1, etc., and descriptions thereof will be omitted. The main difference between wireless communication system 201 and wireless communication system 1 according to the first embodiment is that the receiving device (receiver 2 or relay receiver 4E), rather than the relay device, determines whether or not the relay device (relay device 4 or relay device 4D) transitions to the relay communication mode.

[0190] 23, area E18 of information memory 24 of receiver 2 temporarily stores address information of a transmitting device (transmitter 3 or relay transmitter 4F) received from a communication device (relay device) detected by search. Area E19 of information memory 24 of receiver 2 temporarily stores address information (destination receiving device address information) of a receiving device registered as a destination in the transmitting device (transmitter 3 or relay transmitter 4F) received from a communication device (relay device) detected by search. In this embodiment, areas E18 and E19 are temporary storage areas for temporarily storing information.

[0191] As shown in FIG. 24, in the receiving device-repeater-transmitter pairing, when the receiving device (receiver 2 or relay receiver 4E) and the transmitter (transmitter 3 or relay transmitter 4F) are in the second receiver pairing mode and the second transmitter pairing mode, respectively, and the repeater (repeater 4 or repeater 4D) is in the repeater pairing mode, connection information is transmitted and received between the receiving device and the repeater, and between the repeater and the transmitter (step S5 in FIG. 6: receiving device-repeater-transmitter pairing; step S163 in FIG. 18: receiving device-repeater-transmitter pairing; step S173 in FIG. 20: receiving device-repeater-transmitter pairing). In this case, as shown in FIG. 24, first, connection information is transmitted and received between the repeater and the transmitter, and then connection information is transmitted and received between the receiving device and the repeater.

[0192] The receiver-repeater-transmitter pairing of the wireless communication system 201 of the second embodiment will be described in detail below, taking as an example a case where the receiver, the repeater, and the transmitter are the receiver 2, the repeater 4, and the transmitter 3, respectively. As described above, when the quality of wireless communication between the receiver 2 and the transmitter 3 deteriorates while the receiver 2 and the transmitter 3 are registered with each other as communicators to communicate wirelessly, the communication quality deterioration flag 39A of the control unit 33 of the transmitter 3 is turned on, and the first communication quality deterioration flag 29A of the control unit 23 of the receiver 2 is turned on. When the communication quality deterioration flag 39A of the transmitter 3 is turned on, the transmitter 3 enters the second transmitter pairing mode. When the first communication quality deterioration flag 29A of the receiver 2 is turned on, the receiver 2 enters the second receiver pairing mode. In this state, an operator places the repeater 4 as a repeater in a position where it can communicate well with both the receiver 2 and the transmitter 3. When the operator turns on the power of the repeater 4, the repeater 4 enters the repeater pairing mode if one or both of the receiver and the transmitter to communicate wirelessly with the repeater 4 are not registered. During the repeater pairing mode, the control unit 43 of the repeater 4 executes a first repeater pairing process for transmitting and receiving information with a transmitting device (transmitter 3 or relay transmitter 4F) in the second transmitter pairing mode, and a second repeater pairing process for transmitting and receiving information with a receiving device (receiver 2 or relay receiver 4E) in the second receiver pairing mode.

[0193] First, the second transmitter pairing mode of the transmitter 3 and the first repeater pairing process of the repeater 4 for realizing receiving device-repeater-transmitting device pairing will be described.

[0194] The second transmitter pairing mode of the transmitter 3 is the same as that of the first embodiment. Therefore, the processing flow in the second transmitter pairing mode of the transmitter 3 will be described with reference to Figures 13A and 13B.

[0195] During the second transmitter pairing mode, the control unit 33 of the transmitter 3 searches for a relay (relay device) with which to communicate wirelessly (first relay device search step, step S121 in FIG. 13A). In this case, the control unit 33 of the transmitter 3 detects a communication device within a range in which the transmitter 3 can communicate, and transmits connection information of the transmitter 3 itself (transmitter device connection information) to that communication device (steps S122 and S123 in FIG. 13A). The connection information transmitted from the transmitter 3 includes address information of the transmitter 3 itself, a group ID assigned to the transmitter 3 itself, a communication type of the transmitter 3 itself, and address information of a receiving device registered with the transmitter 3 as a connection destination.

[0196] The control unit 33 of the transmitter 3 receives connection information of the detected communication device from the communication device (step S124 in FIG. 13A). If the group ID received from the detected communication device matches the group ID assigned to the transmitter 3 itself (YES in step S125 in FIG. 13A), and if the communication type received from the communication device is "relay" (YES in step S126 in FIG. 13A), the control unit 33 of the transmitter 3 provisionally stores the address information of the communication device in area E26 of the information memory 34 of the transmitter 3. As a result, the detected communication device is provisionally registered in the transmitter 3 as a relay device with which to communicate wirelessly (step S127 in FIG. 13A). If the group ID received from the detected communication device does not match the group ID assigned to the transmitter 3 itself (NO in step S125 of FIG. 13A), and if the communication type received from the detected communication device is other than "relay" (NO in step S126 of FIG. 13A), the control unit 33 of the transmitter 3 re-searches for the relay device 4 to which to wirelessly connect (step S121 of FIG. 13A). Subsequent processing in the second transmitter pairing mode will be described later.

[0197] The first repeater pairing process of the repeater 4 is the same as that of the first embodiment. Therefore, the processing flow of the first repeater pairing process of the repeater 4 will be described with reference to FIG. 14. In the repeater pairing mode, the control unit 43 of the repeater 4 searches for a transmitting device to be wirelessly connected (transmitting device search step, step S141 in FIG. 14). In this case, the control unit 43 of the repeater 4 detects a communication device in pairing mode that is within a communication range with the repeater 4, and transmits connection information of the repeater 4 itself to that communication device (steps S142 and S143 in FIG. 14).

[0198] The control unit 43 of the repeater 4 receives connection information of the detected communication device from the detected communication device (step S144 in FIG. 14). The connection information received by the repeater 4 includes address information of the detected communication device, a group ID assigned to the communication device, a communication type of the communication device, and address information of communication devices registered as connection destinations with the communication device. If the group ID received from the detected communication device matches the group ID assigned to the repeater 4 itself (YES in step S145 in FIG. 14), and the communication type received from the communication device is “transmission” or “relay transmission” (YES in step S146 in FIG. 14), the control unit 43 of the repeater 4 provisionally registers the communication device in the repeater 4 as a transmitting device with which to communicate wirelessly (step S147 in FIG. 14). Specifically, the address information of the detected communication device and the address information of communication devices registered as connection destinations with the communication device are stored in areas E36 and E37 of the information memory 44 of the repeater 4, respectively. This completes the first repeater pairing process. If the group ID received from the detected communication device does not match the group ID assigned to the repeater 4 itself (NO in step S145 of FIG. 14), and if the communication type received from the detected communication device is other than "transmission" or "relay transmission" (NO in step S146 of FIG. 14), the control unit 43 of the repeater 4 re-searches for a transmitting device with which to communicate wirelessly (step S141 of FIG. 14).

[0199] Next, the second receiver pairing mode of the receiver 2 and the second repeater pairing process of the repeater 4 for realizing receiving device-repeater-transmitting device pairing will be described.

[0200] 25 and 26 are flowcharts illustrating a process flow in the second receiver pairing mode of the receiver 2 included in the wireless communication system 201 according to the second embodiment of the present invention. During the second receiver pairing mode, the control unit 23 of the receiver 2 searches for a relay (relay device) with which to communicate wirelessly (second relay device search step, step S201 in FIG. 25). In this case, if a communication device (receiver, transmitter, or relay device) in pairing mode is within a communication range with the receiver 2 (YES in step S202 in FIG. 25), the receiver 2 detects this communication device through search. Upon detecting a communication device in pairing mode through search, the control unit 23 of the receiver 2 transmits connection information of the receiver 2 itself (receiving device connection information) to the communication device detected through search (step S203 in FIG. 25). The connection information transmitted from the receiver 2 is information stored in areas E11 to E13 of the information memory 24 of the receiver 2, i.e., the address information of the receiver 2 itself, the group ID assigned to the receiver 2 itself, and the communication type of the receiver 2 itself. At this time, the receiver 2 sends "reception" as the communication type.

[0201] The control unit 23 of the receiver 2 receives connection information of the detected communication device from the detected communication device (step S204 in FIG. 25). The connection information received by the receiver 2 includes address information of the detected communication device, a group ID assigned to the detected communication device, and a communication type of the detected communication device. In the second embodiment, the connection information received by the receiver 2 includes address information of the detected communication device (transmitting device) received by the control unit 43 of the repeater 4 in step S144 in FIG. 14, and address information of a communication device (receiving device) that has been registered as a connection destination for the detected communication device (transmitting device).

[0202] Then, if the group ID received from the detected communication device matches the group ID assigned to the receiver 2 itself (YES in step S205 of FIG. 25) and the communication type received from the detected communication device is "relay" (YES in step S206 of FIG. 25), the control unit 23 of the receiver 2 provisionally stores the address information of the detected communication device, the address information of the transmitting device (transmitter 3 or relay transmitter 4F) received from the detected communication device, and the address information of the receiving device registered as a connection destination with the transmitting device (transmitter 3 or relay transmitter 4F) received from the detected communication device in areas E16, E18, and E19, respectively, of the information memory 24 of the receiver 2. As a result, the detected communication device is provisionally registered in the receiver 2 as a relay device with which to communicate wirelessly (step S207 of FIG. 25).

[0203] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the receiver 2 itself (NO in step S205 of FIG. 25), or if the communication type received from the detected communication device is other than "relay" (NO in step S206 of FIG. 25), the control unit 23 of the receiver 2 re-searches for the relay device 4 to which it should wirelessly connect (step S201 of FIG. 25). Subsequent processing in the second transmitter pairing mode will be described later.

[0204] 27 and 28 are flowcharts illustrating the flow of the second repeater pairing process of the repeater 4 included in the wireless communication system according to the second embodiment of the present invention. During the repeater pairing mode, the control unit 43 of the repeater 4 searches for a receiving device (receiver or relay receiver) with which to communicate wirelessly (receiving device search step, step S221 in FIG. 27). In this case, if a communication device (receiver, transmitter, or repeater) in pairing mode is within communication range with the repeater 4 (YES in step S222 in FIG. 27), the repeater 4 detects this communication device. Upon detecting a communication device in pairing mode, the control unit 43 of the repeater 4 transmits its own connection information to the detected communication device (step S223 in FIG. 27). The connection information transmitted from the repeater 4 is information stored in areas E31 to E33, E36, and E37 of the information memory 44 of the repeater 4, namely, the address information of the repeater 4 itself, the group ID assigned to the repeater 4 itself, the communication type of the repeater 4 itself, the address information of the transmitter 3 received by the control unit 43 of the repeater 4, and the address information of the receiving device that has been registered as a connection destination with the transmitter 3 and received by the control unit 43 of the repeater 4.

[0205] The control unit 43 of the repeater 4 receives connection information of the detected communication device from the communication device (step S224 in FIG. 27). The connection information received by the repeater 4 includes address information of the detected communication device, a group ID assigned to the communication device, a communication type of the communication device, and address information of communication devices registered as connection destinations to the communication device.

[0206] If the group ID received from the detected communication device matches the group ID assigned to the repeater 4 itself (YES in step S225 of FIG. 27), and the communication type received from the communication device is "receive" or "relayed receive" (YES in step S226), the control unit 43 of the repeater 4 provisionally registers the communication device in the repeater 4 as a receiving device with which to communicate wirelessly (step S227 of FIG. 27). Specifically, the address information of the communication device and the address information of communication devices already registered as connection destinations for the communication device are stored in areas E38 and E39 of the information memory 44 of the repeater 4, respectively. This completes the second repeater pairing process.

[0207] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the repeater 4 itself (NO in step S225), and if the communication type received from the detected communication device is other than "receive" or "relayed receive" (NO in step S226), the control unit 43 of the repeater 4 re-searches for a receiving device with which to communicate wirelessly without storing address information in the information memory 44 (step S221).

[0208] The subsequent processing in the second relay pairing processing will be described later.

[0209] Returning to Fig. 26, the control unit 23 of the receiver 2 checks whether its own address information matches (compares; step S208 in Fig. 26) the address information of the communication device (relay device) registered as a connection destination in the communication device (transmitting device) received from the communication device (repeater) in step S204 in Fig. 25. Specifically, the control unit 23 of the receiver 2 checks whether the address information stored in areas E11 and E19 of the information memory 24 is the same as each other (determination step).

[0210] Furthermore, the control unit 23 of the receiver 2 checks whether or not the address information of the communication device (transmitting device) received from the communication device (relay device) in step S204 of Fig. 25 matches the address information of the communication device (transmitting device) registered in the receiver 2 as a connection destination (verifies; step S209 of Fig. 26). Specifically, the control unit 23 of the receiver 2 checks whether or not the address information stored in areas E14 and E18 of the information memory 24 is the same (determination step).

[0211] If these two sets of address information match (YES in step S208 and YES in step S209 in FIG. 26), control unit 23 of receiver 2 transmits a connection success notification to repeater 4 (step S211 in FIG. 26). Specifically, it clears the information stored in areas E18 and E19 of information memory 24 (step S210 in FIG. 26), and transmits a connection success notification as a connection notification to the detected communication device (repeater) (step S211 in FIG. 26).

[0212] Then, the provisional registration of the communication device (repeater) to the receiver 2 is switched to official registration. Specifically, the control unit 23 of the receiver 2 stores the address information of the repeater 4 stored in area E16 of the information memory 24 in area E15. The information stored in area E16 may be cleared. This ends the second receiver pairing mode, and the receiver 2 transitions from the second receiver pairing mode to the wireless communication mode.

[0213] On the other hand, if one or both of the two sets of address information combinations do not match (NO in step S208 or NO in step S209 in Figure 26), the control unit 43 of the repeater 4 clears the information stored in areas E16, E18, and E19 of the information memory 24 (step S212 in Figure 26), and sends a connection failure notification as a connection notification to the detected communication device (repeater) (step S213 in Figure 26).

[0214] Next, the process performed by the repeater 4 that has received the connection notification will be described with reference to FIG. 28. If the connection notification received from the detected receiver 2 is a connection failure notification (YES in step S228 of FIG. 28, NO in step S229), the control unit 43 of the repeater 4 transmits a connection failure notification to the detected communication device (transmitter) as the connection notification (step S232 of FIG. 28). The control unit 43 of the repeater 4 also clears the information stored in areas E36 to E39 of the information memory 44 and deletes the provisional registration of the communication device (transmitter and receiver) from the repeater 4 (step S233 of FIG. 28). Thereafter, the control unit 43 of the repeater 4 re-searches for a repeater with which to communicate wirelessly (step S221 of FIG. 27).

[0215] On the other hand, if the connection notification received from the detected receiver 2 is a connection success notification (YES in step S228 of FIG. 28, YES in step S229), the control unit 43 of the repeater 4 switches the registration of the communication device detected by the search to the repeater 4 from provisional registration to formal registration (step S231 of FIG. 28). Specifically, the control unit 43 of the repeater 4 transmits a connection success notification as a connection notification to the detected communication device (transmitting device) (step S230 of FIG. 28). In addition, the control unit 43 of the repeater 4 stores in area E35 the address information of the communication device (receiving device) stored in area E38 of the information memory 44. The information stored in areas E38 and E39 may be cleared. As a result, the communication device that was provisionally registered in the repeater 4 is formally registered in the repeater 4 as a receiving device with which to communicate wirelessly (step S231 of FIG. 28). Furthermore, the control unit 43 of the repeater 4 stores in area E34 the address information of the communication device (transmitting device) stored in area E36 of the information memory 44. The information stored in areas E36 and E37 may be cleared. As a result, the communication device that was provisionally registered in the repeater 4 is officially registered in the repeater 4 as a transmitting device with which to communicate wirelessly. As a result, the repeater pairing mode of the repeater 4 ends.

[0216] Next, the process performed by the transmitter 3 that has received the connection notification will be described with reference to Fig. 13B. If the connection notification received from the detected repeater 4 is a connection failure notification (YES in step S128 of Fig. 13B, NO in step S129), the control unit 33 of the transmitter 3 clears the information stored in area E26 of the information memory 34 and deletes the provisional registration of the communication device (repeater) from the transmitter 3 (step S130 of Fig. 13B). Thereafter, the control unit 23 of the receiver 2 re-searches for the repeater 4 with which to communicate wirelessly (step S121 of Fig. 13A).

[0217] On the other hand, if the connection notification received from the detected repeater 4 is a successful connection notification (YES in step S128 and YES in step S129 in FIG. 13B), the provisional registration of the communication device (repeater) with the receiver 2 is switched to official registration. Specifically, the control unit 33 of the transmitter 3 stores the address information of the repeater 4 stored in area E26 in area E25. The information stored in area E26 may be cleared. This ends the second transmitter pairing mode, and the transmitter 3 transitions from the second transmitter pairing mode to the wireless communication mode.

[0218] After the second receiver pairing mode and the second transmitter pairing mode are terminated, the receiver 2 and the transmitter 3 each transition to wireless communication mode. Furthermore, after the repeater pairing mode is terminated, the repeater 4 transitions to relayed communication mode. The receiver 2, the repeater 4, and the transmitter 3 begin communication with each other based on the address information of the communication devices with which to communicate wirelessly, acquired in the second receiver pairing mode, the repeater pairing mode, and the second transmitter pairing mode. This initiates wireless communication between the receiver 2, the repeater 4, and the transmitter 3.

[0219] As described above, according to the second embodiment, if two communication devices (a transmitting device and a receiving device) have registered each other as wireless communication destinations, the address information of one of the communication devices (the receiving device) matches the address information of the communication device registered as a connection destination in the other communication device (the transmitting device), which is received by one of the communication devices (the receiving device) via a relay device that is to relay wireless communication between the two communication devices. Similarly, if two communication devices (a transmitting device and a receiving device) have registered each other as wireless communication destinations, the address information of the communication device registered as a connection destination in one of the communication devices (the receiving device) matches the address information of the other communication device (the transmitting device), which is received by one of the communication devices (the receiving device) via a relay device that is to relay wireless communication between the two communication devices.

[0220] Since the condition for determining whether to switch to the relayed communication mode is a match between two pairs of address information, rather than just one pair, it is possible to doubly ensure that the two communication devices (the receiving device and the transmitting device) have each other registered as wireless communication destinations in advance, thereby avoiding relay errors such as the relay device 4 relaying a transmitting device and a receiving device that are not intended to communicate wirelessly.

[0221] The same group ID is assigned in advance to the receiver 2, transmitter 3, and repeater 4 that are to communicate wirelessly. In repeater pairing mode, if the group IDs received from two communication devices detected by search match the group ID assigned to the repeater 4, the repeater 4 transitions to relayed communication mode. This prevents wireless communication from being initiated by a receiver 2, transmitter 3, or repeater 4 that is not intended to communicate wirelessly.

[0222] In this embodiment, a match between one pair of address information may be used as a criterion for determining whether to transition to the relay communication mode. Specifically, the relay device 4 may transition to the relay communication mode when only one of the two sets of address information in steps S208 and S209 in Fig. 26 matches. Even when only one pair of address information matches, relay errors can be almost certainly avoided.

[0223] Fig. 29 is a block diagram showing the contents stored in the information memory 34 of the transmitter 3 included in the wireless communication system 301 according to the third embodiment of the present invention. Fig. 30 is a diagram for explaining receiving device-repeater-transmitting device pairing executed in the wireless communication system 301. Figs. 31 and 32 are flowcharts for explaining the processing flow in the second transmitter pairing mode of the transmitter 3 included in the wireless communication system 301. Figs. 33 and 34 are flowcharts for explaining the flow of first repeater pairing processing of the repeater 4 included in the wireless communication system 301.

[0224] 29 to 34, components equivalent to those shown in the above-described Figures 1 to 22 are given the same reference numerals as in Figure 1, etc., and descriptions thereof will be omitted. The main difference between wireless communication system 301 and wireless communication system 1 according to the first embodiment is that the transmitter (transmitter 3 or relay transmitter 4F), rather than the relay device, determines whether or not the relay device (relay device 4 or relay device 4D) transitions to the relay communication mode.

[0225] 29, area E28 of the information memory 34 of the transmitter 3 temporarily stores address information of a receiving device (receiver 2 or relay receiver 4E) received from a communication device (relay device) detected by a search. Area E29 of the information memory 34 of the transmitter 3 temporarily stores address information (destination transmitter address information) of a transmitting device that has been registered as a connection destination in the receiving device (receiver 2 or relay receiver 4E) received from a communication device (relay device) detected by a search. In this embodiment, areas E28 and E29 are temporary storage areas for temporarily storing information.

[0226] As shown in FIG. 30, in the receiving device-repeater-transmitter pairing, the receiving device (receiver 2 or relay receiver 4E) and the transmitter (transmitter 3 or relay transmitter 4F) are in the second receiver pairing mode and the second transmitter pairing mode, respectively, and the repeater (repeater 4 or repeater 4D) is in the repeater pairing mode. In this state, connection information is transmitted and received between the receiving device and the repeater, and between the repeater and the transmitter (step S5 in FIG. 6: receiving device-repeater-transmitter pairing; step S163 in FIG. 18: receiving device-repeater-transmitter pairing; step S173 in FIG. 20: receiving device-repeater-transmitter pairing). In this embodiment, unlike the first and second embodiments, connection information is first transmitted and received between the repeater and the receiving device, and then connection information is transmitted and received between the transmitter and the repeater.

[0227] The receiver-repeater-transmitter pairing of the wireless communication system 301 of the third embodiment will be described in detail below, taking as an example a case where the receiver, the repeater, and the transmitter are the receiver 2, the repeater 4, and the transmitter 3, respectively. As described above, when the quality of wireless communication between the receiver 2 and the transmitter 3 is degraded while the receiver 2 and the transmitter 3 are registered with each other as communicators to communicate wirelessly, the communication quality degradation flag 39A of the control unit 33 of the transmitter 3 is turned on, and the first communication quality degradation flag 29A of the control unit 23 of the receiver 2 is turned on. When the communication quality degradation flag 39A of the transmitter 3 is turned on, the transmitter 3 enters the second transmitter pairing mode. When the first communication quality degradation flag 29A of the receiver 2 is turned on, the receiver 2 enters the second receiver pairing mode. In this state, an operator places the repeater 4 as a repeater in a position where it can communicate well with both the receiver 2 and the transmitter 3. When the operator turns on the power of the repeater 4, the repeater 4 enters the repeater pairing mode if one or both of the receiver and the transmitter to communicate wirelessly with the repeater 4 are not registered. During the repeater pairing mode, the control unit 43 of the repeater 4 executes a second repeater pairing process for transmitting and receiving information with a receiving device (receiver 2 or relay receiver 4E) in the second receiver pairing mode, and a first repeater pairing process for transmitting and receiving information with a transmitting device (transmitter 3 or relay transmitter 4F) in the second transmitter pairing mode.

[0228] First, the second receiver pairing mode of the receiver 2 and the second repeater pairing process of the repeater 4 for realizing receiving device-repeater-transmitting device pairing will be described.

[0229] The second receiver pairing mode of the receiver 2 is the same as in the first embodiment, so the processing flow in the second receiver pairing mode of the receiver 2 will be described with reference to Figures 15A and 15B.

[0230] During the second receiver pairing mode, the control unit 23 of the receiver 2 searches for a relay (relay device) with which to communicate wirelessly (second relay device search step, step S91 in FIG. 15A). In this case, the control unit 23 of the receiver 2 detects a communication device within a range in which the receiver 2 can communicate, and transmits the connection information of the receiver 2 itself (receiving device connection information) to that communication device (steps S92 and S93 in FIG. 15A). The connection information transmitted from the receiver 2 includes the address information of the receiver 2 itself, the group ID assigned to the receiver 2 itself, the communication type of the receiver 2 itself, and the address information of a transmitting device registered as a connection destination for the receiver 2.

[0231] The control unit 23 of the receiver 2 receives connection information of the detected communication device from the communication device (step S94 in FIG. 15A). If the group ID received from the detected communication device matches the group ID assigned to the receiver 2 itself (YES in step S95 in FIG. 15A), and if the communication type received from the communication device is "relay" (YES in step S96 in FIG. 15A), the control unit 23 of the receiver 2 provisionally stores the address information of the communication device in area E26 of the information memory 24 of the receiver 2. As a result, the detected communication device is provisionally registered in the receiver 2 as a relay device with which to communicate wirelessly (step S97 in FIG. 15A). If the group ID received from the detected communication device does not match the group ID assigned to the receiver 2 itself (NO in step S95 of FIG. 15A), or if the communication type received from the detected communication device is other than "relay" (NO in step S96 of FIG. 15A), the control unit 23 of the receiver 2 re-searches for the relay device 4 to which it should wirelessly connect (step S91 of FIG. 15A). Subsequent processing in the second receiver pairing mode will be described later.

[0232] The second repeater pairing process of the repeater 4 is the same as that of the first embodiment. Therefore, the processing flow of the second repeater pairing process of the repeater 4 will be described with reference to FIG. 16. In the repeater pairing mode, the control unit 43 of the repeater 4 searches for a receiving device (receiver or relay receiver) to be wirelessly connected (receiving device search step, step S111 in FIG. 16). In this case, the control unit 43 of the repeater 4 detects a communication device in pairing mode that is within a communication range with the repeater 4, and transmits connection information of the repeater 4 itself to that communication device (steps S112 and S113 in FIG. 16).

[0233] The control unit 43 of the repeater 4 receives connection information of the detected communication device from the detected communication device (step S114 in FIG. 16). The connection information received by the repeater 4 includes address information of the detected communication device, a group ID assigned to the communication device, a communication type of the communication device, and address information of communication devices registered as connection destinations with the communication device. If the group ID received from the detected communication device matches the group ID assigned to the repeater 4 itself (YES in step S115 in FIG. 16), and the communication type received from the communication device is "reception" or "relayed reception" (YES in step S116 in FIG. 16), the control unit 43 of the repeater 4 provisionally registers the communication device in the repeater 4 as a receiving device with which to communicate wirelessly (step S117 in FIG. 16). Specifically, the address information of the detected communication device and the address information of communication devices registered as connection destinations with the communication device are stored in areas E38 and E39 of the information memory 44 of the repeater 4, respectively. This completes the second repeater pairing process. If the group ID received from the detected communication device does not match the group ID assigned to the repeater 4 itself (NO in step S115 of FIG. 16), and if the communication type received from the detected communication device is other than "transmission" or "relay transmission" (NO in step S116 of FIG. 16), the control unit 43 of the repeater 4 re-searches for a receiving device with which to communicate wirelessly (step S111 of FIG. 16).

[0234] Next, the second transmitter pairing mode of the transmitter 3 and the first repeater pairing process of the repeater 4 for realizing receiver-repeater-transmitter pairing will be described. As in the first embodiment, the first repeater pairing process of the repeater 4 is a process for transmitting and receiving information with a transmitter (transmitter 3 or repeater transmitter 4F) in the second receiver pairing mode.

[0235] 31 and 32 are flowcharts illustrating a process flow in the second transmitter pairing mode of the transmitter 3 included in the wireless communication system 301 according to the third embodiment of the present invention. During the second transmitter pairing mode, the control unit 33 of the transmitter 3 searches for a relay (relay device) with which to communicate wirelessly (first relay device search step, step S301 in FIG. 31). In this case, if a communication device (transmitter, receiver, or relay device) in pairing mode is present within a communicable range with the transmitter 3 (YES in step S302 in FIG. 31), the transmitter 3 detects this communication device through the search. Upon detecting a communication device in pairing mode through the search, the control unit 33 of the transmitter 3 transmits connection information of the transmitter 3 itself (transmitter device connection information) to the communication device detected through the search (step S303 in FIG. 31). The connection information transmitted from the transmitter 3 is information stored in areas E21 to E23 of the information memory 34 of the transmitter 3, namely, the address information of the transmitter 3 itself, the group ID assigned to the transmitter 3 itself, and the communication type of the transmitter 3 itself. At this time, the transmitter 3 transmits "transmission" as the communication type.

[0236] The control unit 33 of the transmitter 3 receives connection information of the searched communication device from the searched communication device (step S304 in FIG. 31). The connection information received by the transmitter 3 includes address information of the detected communication device, a group ID assigned to the detected communication device, and a communication type of the detected communication device. In the third embodiment, the connection information received by the transmitter 3 includes address information of the detected communication device (receiving device) received by the control unit 43 of the repeater 4 in step S114 in FIG. 16, and address information of a communication device (transmitting device) that has been registered as a connection destination for the detected communication device (receiving device).

[0237] Then, if the group ID received from the detected communication device matches the group ID assigned to the transmitter 3 itself (YES in step S305 of FIG. 31) and the communication type received from the detected communication device is "relay" (YES in step S306 of FIG. 31), the control unit 33 of the transmitter 3 provisionally stores the address information of the detected communication device, the address information of the receiving device (receiver 2 or relay receiver 4E) received from the detected communication device, and the address information of a transmitting device registered as a connection destination in the receiving device (receiver 2 or relay receiver 4E) received from the detected communication device in areas E26, E28, and E29, respectively, of the information memory 34 of the transmitter 3. As a result, the detected communication device is provisionally registered in the transmitter 3 as a relay device with which to communicate wirelessly (step S307 of FIG. 31).

[0238] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the transmitter 3 itself (NO in step S305 of FIG. 31), and if the communication type received from the detected communication device is other than "relay" (NO in step S306 of FIG. 31), the control unit 33 of the transmitter 3 re-searches for the relay device 4 to which to wirelessly connect (step S301 of FIG. 31). Subsequent processing in the second receiver pairing mode will be described later.

[0239] 33 and 34 are flowcharts illustrating the flow of the first repeater pairing process of the repeater 4 included in the wireless communication system according to the third embodiment of the present invention. In the repeater pairing mode, the control unit 43 of the repeater 4 searches for a transmitting device (transmitter or repeater transmitter) with which to communicate wirelessly (transmitter search step, step S321 in FIG. 33). In this case, if a communication device (transmitter, receiver, or repeater) in pairing mode is within a communication range with the repeater 4 (YES in step S322 in FIG. 33), the repeater 4 detects this communication device. Upon detecting a communication device in pairing mode, the control unit 43 of the repeater 4 transmits its own connection information to the detected communication device (step S323 in FIG. 33). The connection information transmitted from the repeater 4 is information stored in areas E31 to E33, E38, and E39 of the information memory 44 of the repeater 4, namely, the address information of the repeater 4 itself, the group ID assigned to the repeater 4 itself, the communication type of the repeater 4 itself, the address information of the receiver 2 received by the control unit 43 of the repeater 4, and the address information of a transmitting device that has been registered as a connection destination for the receiver 2 and received by the control unit 43 of the repeater 4.

[0240] The control unit 43 of the repeater 4 receives connection information of the detected communication device from the communication device (step S324 in FIG. 33). The connection information received by the repeater 4 includes address information of the detected communication device, a group ID assigned to the communication device, a communication type of the communication device, and address information of communication devices registered as connection destinations to the communication device.

[0241] If the group ID received from the detected communication device matches the group ID assigned to the repeater 4 itself (YES in step S325 of FIG. 33), and the communication type received from the communication device is "transmission" or "relay transmission" (YES in step S326), the control unit 43 of the repeater 4 provisionally registers the communication device in the repeater 4 as a transmitting device with which to communicate wirelessly (step S327 of FIG. 33). Specifically, the address information of the communication device and the address information of communication devices already registered as connection destinations for the communication device are stored in areas E36 and E37 of the information memory 44 of the repeater 4, respectively. This completes the first repeater pairing process.

[0242] On the other hand, if the group ID received from the detected communication device does not match the group ID assigned to the repeater 4 itself (NO in step S325), and if the communication type received from the detected communication device is other than "receive" or "relayed receive" (NO in step S326), the control unit 43 of the repeater 4 re-searches for the transmitting device with which to communicate wirelessly without storing the address information in the information memory 44 (step S321).

[0243] The subsequent processing in the first relay pairing processing will be described later.

[0244] Returning to Fig. 32, the control unit 33 of the transmitter 3 checks whether its own address information matches (compares) the address information of the communication device (transmitting device) registered as a connection destination in the communication device (receiving device) received from the communication device (repeater) in step S304 of Fig. 31. Specifically, the control unit 33 of the transmitter 3 checks whether the address information stored in areas E21 and E29 of the information memory 34 is the same as each other (determination step).

[0245] Furthermore, the control unit 33 of the transmitter 3 checks whether or not the address information of the communication device (receiving device) received from the communication device (relay device) in step S304 of Fig. 31 matches (compares) the address information of the communication device (receiving device) already registered in the transmitter 3 as a connection destination. Specifically, the control unit 33 of the transmitter 3 checks whether or not the address information stored in areas E24 and E28 of the information memory 34 is the same (determination step).

[0246] If these two sets of address information match (YES in step S308 and YES in step S309 in FIG. 32), the control unit 33 of the transmitter 3 transmits a connection success notification to the repeater 4 (step S311 in FIG. 32). Specifically, the information stored in areas E28 and E29 of the information memory 34 is cleared (step S310 in FIG. 32), and a connection success notification is transmitted to the detected communication device (repeater) as a connection notification (step S311 in FIG. 32).

[0247] Then, the provisional registration of the communication device (repeater) with the transmitter 3 is switched to official registration. Specifically, the control unit 33 of the transmitter 3 stores the address information of the repeater 4 stored in area E26 of the information memory 34 in area E25. The information stored in area E26 may be cleared. This ends the second transmitter pairing mode, and the transmitter 3 transitions from the second transmitter pairing mode to the wireless communication mode.

[0248] On the other hand, if one or both of the two sets of address information combinations do not match (NO in step S308 or NO in step S309 in Figure 32), the control unit 43 of the repeater 4 clears the information stored in areas E26, E28, and E29 of the information memory 34 (step S312 in Figure 32), and sends a connection failure notification as a connection notification to the detected communication device (repeater) (step S313 in Figure 32).

[0249] Next, the process performed by the repeater 4 that has received the connection notification will be described with reference to FIG. 34. If the connection notification received from the detected transmitter 3 is a connection failure notification (YES in step S328 of FIG. 34, NO in step S329), the control unit 43 of the repeater 4 transmits a connection failure notification to the detected communication device (receiving device) as the connection notification (step S332 of FIG. 34). The control unit 43 of the repeater 4 also clears the information stored in areas E36 to E39 of the information memory 44 and deletes the provisional registration of the communication device (receiving device and transmitting device) from the repeater 4 (step S333 of FIG. 34). Thereafter, the control unit 43 of the repeater 4 re-searches for a repeater with which to communicate wirelessly (step S321 of FIG. 33).

[0250] On the other hand, if the connection notification received from the detected transmitter 3 is a connection success notification (YES in step S328 of FIG. 34, YES in step S329), the control unit 43 of the repeater 4 switches the registration of the communication device detected by the search to the repeater 4 from provisional registration to formal registration (step S331 of FIG. 34). Specifically, the control unit 43 of the repeater 4 transmits a connection success notification as a connection notification to the detected communication device (receiving device) (step S330 of FIG. 34). In addition, the control unit 43 of the repeater 4 stores in area E34 the address information of the communication device (transmitting device) stored in area E36 of the information memory 44. The information stored in areas E36 and E37 may be cleared. As a result, the communication device that was provisionally registered in the repeater 4 is formally registered in the repeater 4 as a transmitting device with which to communicate wirelessly (step S331 of FIG. 34). Furthermore, the control unit 43 of the repeater 4 stores the address information of the communication device (transmitting device) stored in area E38 of the information memory 44 in area E35. The information stored in areas E38 and E39 may be cleared. As a result, the communication device that was provisionally registered in the repeater 4 is officially registered in the repeater 4 as a transmitting device with which to communicate wirelessly. As a result, the repeater pairing mode of the repeater 4 ends.

[0251] Next, the processing performed by the receiver 2 that has received the connection notification will be described with reference to Fig. 15B. If the connection notification received from the detected repeater 4 is a connection failure notification (YES in step S98 of Fig. 15B, NO in step S99), the control unit 23 of the receiver 2 clears the information stored in area E26 of the information memory 34 and deletes the provisional registration of the communication device (repeater) from the receiver 2 (step S100 of Fig. 15B). Thereafter, the control unit 33 of the transmitter 3 re-searches for the repeater 4 with which to communicate wirelessly (step S91 of Fig. 15A).

[0252] On the other hand, if the connection notification received from the detected repeater 4 is a successful connection notification (YES in step S98 and YES in step S99 in FIG. 15B), the provisional registration of the communication device (repeater) with the transmitter 3 is switched to official registration. Specifically, the control unit 23 of the receiver 2 stores the address information of the repeater 4 stored in area E16 in area E15. The information stored in area E16 may be cleared. This ends the second receiver pairing mode, and the receiver 2 transitions from the second receiver pairing mode to the wireless communication mode.

[0253] After the second transmitter pairing mode and the second receiver pairing mode are terminated, the transmitter 3 and the receiver 2 each transition to wireless communication mode. Furthermore, after the repeater pairing mode is terminated, the repeater 4 transitions to relayed communication mode. The transmitter 3, the repeater 4, and the receiver 2 begin communicating with each other based on the address information of the communication devices with which to communicate wirelessly, acquired through the second transmitter pairing mode, the repeater pairing mode, and the second receiver pairing mode. This initiates wireless communication between the transmitter 3, the repeater 4, and the receiver 2.

[0254] As described above, according to the third embodiment, if two communication devices (a transmitting device and a receiving device) have registered each other as wireless communication destinations, the address information of one communication device (the transmitting device) matches the address information of the communication device registered as a connection destination in the other communication device (the receiving device) that is received by one communication device (the transmitting device) via a relay device that is to relay wireless communication between the two communication devices. Similarly, if two communication devices (a transmitting device and a receiving device) have registered each other as wireless communication destinations, the address information of the communication device registered as a connection destination in one communication device (the transmitting device) matches the address information of the other communication device (the receiving device) that is received by one communication device (the transmitting device) via a relay device that is to relay wireless communication between the two communication devices.

[0255] Since the condition for determining whether to switch to the relayed communication mode is a match between two pairs of address information, rather than just one pair, it is possible to doubly ensure that the two communication devices (transmitter and receiver) have registered each other as wireless communication destinations in advance, thereby avoiding relay errors such as relaying a receiver and transmitter that are not intended to communicate wirelessly with the relay device 4.

[0256] The same group ID is assigned in advance to the transmitter 3, receiver 2, and repeater 4 that are to communicate wirelessly. In the repeater pairing mode, if the group IDs received from two communication devices detected by a search match the group ID assigned to the repeater 4, the repeater 4 transitions to the relayed communication mode. This prevents wireless communication from being initiated by a transmitter 3, receiver 2, or repeater 4 that is not intended to communicate wirelessly.

[0257] In this embodiment, a match between one pair of address information may be used as a criterion for determining whether to transition to the relay communication mode. Specifically, the relay device 4 may transition to the relay communication mode when only one of the two sets of address information in steps S308 and S309 in FIG. 32 matches. Even when only one pair of address information matches, relay errors can be almost certainly avoided.

[0258] Although three embodiments of the present invention have been described above, the present invention can also be embodied in other forms.

[0259] For example, the communication types of the relay device 4 have been described as three types, "relay," "relay reception," and "relay transmission," but may be two types, "relay reception" and "relay transmission," instead of three types.

[0260] In this case, the initial state of the communication type of the repeater 4 after power-on is, for example, "relay reception." In the second repeater pairing process of the repeater 4 in the second receiver pairing mode (step S82 in FIG. 12), the communication type of the repeater 4 switches to "relay transmission." In the first repeater pairing process of the repeater 4 in the second receiver pairing mode (step S81 in FIG. 12), the communication type of the repeater 4 switches to "relay reception." When the repeater 4 transitions to the second receiver pairing mode, the communication type switches to "relay reception." When the repeater 4 transitions to the second transmitter pairing mode, the communication type switches to "relay transmission."

[0261] Furthermore, the group ID assigned to the wirelessly communicating receiver 2, repeater 4, and transmitter 3 may be an ID commonly assigned to specific devices from an equipment vendor, such as "AAA." In this case, it is distinguished from an ID commonly assigned to specific devices from the same equipment vendor, such as "AAB." The group ID may also indicate the name of the equipment vendor, etc. In this case, a common group ID is assigned to devices from the same equipment vendor.

[0262] In addition, if a group ID is commonly assigned to specific devices of an equipment vendor or commonly assigned to devices of the same equipment vendor, the control unit 43 of the repeater 4 may be configured to search for and detect only communication devices with matching group IDs in a search for communication devices (step S141 in Figure 14, step S111 in Figure 16, step S221 in Figure 27, and step S321 in Figure 33).

[0263] Furthermore, in receiving device-repeater-transmitting device pairing (step S5 in FIG. 6, step S163 in FIG. 18, step S173 in FIG. 20, etc.), the group ID does not have to be included in the connection information exchanged. In other words, matching the group IDs does not have to be a condition for exchanging connection information in receiving device-repeater-transmitting device pairing.

[0264] On the other hand, in receiver-transmitter pairing (step S2 in FIG. 6), it is desirable that the group ID be included in the connection information exchanged. In other words, it is desirable that the matching of the group IDs be a condition for exchanging connection information in receiver-transmitter pairing (step S2 in FIG. 6). This is to reliably prevent one receiver 2 from being connected to multiple transmitters 3 at the same time, or multiple receivers 2 from being connected to one transmitter 3 at the same time.

[0265] Furthermore, the temporary information storage areas (areas E16, E18, E19 in FIGS. 3 and 23, areas E26, E28, E29 in FIGS. 4 and 29, and areas E36 to E39 in FIG. 5) for temporarily storing information may be eliminated in the information memories 24, 34, 44. In this case, the information temporarily stored in the temporary storage areas may be directly written to the corresponding storage areas among the storage areas (areas E11 to E15 in FIGS. 3 and 23, areas E21 to E25 in FIGS. 4 and 29, and areas E131 to E35 in FIG. 5), and then cleared as necessary.

[0266] Furthermore, although the wireless communication systems 1, 201, and 301 have been described as being applied to the production system 10, the wireless communication systems 1, 201, and 301 can also be applied to other systems.

[0267] In addition, various design modifications can be made within the scope of the claims.

[0268] This application corresponds to Patent Application No. 2022-188968 filed with the Japan Patent Office on November 28, 2022, the entire disclosure of which is incorporated herein by reference. [Explanation of symbols]

[0269] 1: Wireless communication system 2: Receiver 3: Transmitter 4: Repeater (relay device) 4D: Repeater (relay device) 4E: Relay receiver (receiving device) 4F: Relay transmitter (transmitting device) 11: Production equipment 12: Alarm device 23: Control unit (receiving device control unit) 33: Control unit (transmission device control unit) 43: Control unit (relay device control unit, receiving device control unit, transmitting device control unit) 201: Wireless communication system 301: Wireless communication systems

Claims

1. a transmitting device and a receiving device which have each registered in advance as a wireless communication destination; a relay device that relays wireless communication between the receiving device and the transmitting device, the transmitting device includes a transmitting device control unit that executes a first relay device search step of searching for a relay device in a pairing mode; the receiving device includes a receiving device control unit that executes a second relay device search step of searching for a relay device in a pairing mode; the transmitting device control unit and the receiving device control unit execute at least one of the steps of: transmitting, to the relay device detected by the search, transmitting device connection information including transmitting device address information which is address information of the transmitting device and destination receiving device address information which is address information of the receiving device registered as a destination to the transmitting device; and transmitting, to the relay device detected by the search, receiving device connection information including receiving device address information which is address information of the receiving device and destination transmitting device address information which is address information of the transmitting device registered as a destination to the receiving device; The relay device a receiving device search step of searching for a receiving device during the pairing mode, and receiving, from the receiving device detected by the search, receiving device connection information including receiving device address information that is address information of the receiving device and destination transmitting device address information that is address information of the transmitting device that has been registered as a connection destination in the receiving device; a relay device control unit that executes a transmitting device searching step of searching for a transmitting device during the pairing mode, and receiving, from the transmitting device detected by the search, transmitting device connection information including transmitting device address information that is address information of the transmitting device and destination receiving device address information that is address information of the receiving device that has been registered as a connection destination in the transmitting device; A wireless communication system in which one of the receiving device control unit, the transmitting device control unit, and the relay device control unit executes a determination step to determine whether the relay device will transition from the pairing mode to a relay communication mode in which wireless communication between the receiving device and the transmitting device is relayed based on at least one of destination transmitting device address information, which is address information of the transmitting device that has been registered as a destination in the receiving device, and destination receiving device address information, which is address information of the receiving device that has been registered as a destination in the transmitting device.

2. 2. The wireless communication system of claim 1, wherein in the determination step, the relay device control unit determines whether to transition to the relay communication mode based on at least one of a comparison between the receiving device address information received by the relay device from the detected receiving device and the destination receiving device address information received by the relay device from the detected transmitting device, and a comparison between the transmitting device address information received by the relay device from the detected transmitting device and the destination transmitting device address information received by the relay device from the detected receiving device.

3. the relay device control unit determines in the determining step to transition to the relay communication mode when the receiving device address information received by the relay device from the detected receiving device matches the destination receiving device address information received by the relay device from the detected transmitting device, and the transmitting device address information received by the relay device from the detected transmitting device matches the destination transmitting device address information received by the relay device from the detected receiving device; 3. The wireless communication system according to claim 2, wherein the relay device determines not to transition to the relay communication mode when the receiving device address information received by the relay device from the detected receiving device does not match the destination receiving device address information received by the relay device from the detected transmitting device, or when the transmitting device address information received by the relay device from the detected transmitting device does not match the destination transmitting device address information received by the relay device from the detected receiving device.

4. the receiving device connection information and the transmitting device connection information include group identification information assigned to the receiving device and the transmitting device, respectively; 4. The wireless communication system according to claim 3, wherein the relay device control unit determines not to transition to the relay communication mode in the determination step when group identification information included in the receiving device connection information received by the relay device from the detected receiving device does not match group identification information assigned to the relay device, or when group identification information included in the transmitting device connection information received by the relay device from the detected transmitting device does not match group identification information assigned to the relay device.

5. The relay device control unit a step of transmitting, to the receiving device detected by the search in the receiving device search step, one or both of the transmitting device address information and the destination receiving device address information included in the transmitting device connection information received from the transmitting device detected in the transmitting device search step; the receiving device control unit executes a step of receiving both or one of the transmitting device address information and the destination receiving device address information included in the transmitting device connection information from the relay device detected in the second relay device search step; 2. The wireless communication system of claim 1, wherein in the determination step, the receiving device control unit determines whether the relay device will transition from the pairing mode to the relay communication mode based on at least one of comparing the receiving device address information of the receiving device with the destination receiving device address information included in the transmitting device connection information, and comparing the address information of the transmitting device registered as a destination in the receiving device with the transmitting device address information included in the transmitting device connection information.

6. The relay device control unit a step of transmitting, to the transmitting device detected by the search in the transmitting device search step, one or both of the receiving device address information and the destination transmitting device address information included in the receiving device connection information received from the receiving device detected in the receiving device search step; the transmitting device control unit executes a step of receiving, from the relay device detected in the first relay device search step, one or both of the receiving device address information and the destination transmitting device address information included in the receiving device connection information; 2. The wireless communication system of claim 1, wherein in the determination step, the transmitting device control unit determines whether the relay device will transition from the pairing mode to the relay communication mode based on at least one of comparing the transmitting device address information of the transmitting device with the destination transmitting device address information included in the receiving device connection information, and comparing the address information of the receiving device that has been registered as a destination on the transmitting device with the receiving device address information included in the receiving device connection information.

7. The wireless communication system according to any one of claims 1 to 6, wherein when the power of the relay device is turned on, if one or both of the receiving device and the transmitting device to which communication is to be relayed are not registered, the relay device enters the pairing mode.

8. the receiving device enters the pairing mode when a wireless communication failure occurs between the receiving device and the transmitting device, 7. The wireless communication system according to claim 1, wherein the transmitting device enters the pairing mode when a failure in wireless communication with the receiving device occurs.

9. A wireless communication system according to any one of claims 1 to 6, wherein the transmitting device is a transmitter or another relay.

10. A wireless communication system according to any one of claims 1 to 6, wherein the receiving device is a receiver or another repeater.

11. The wireless communication system of claim 9 , wherein the transmitter is connected to a production device.

12. The wireless communication system of claim 10, wherein the receiver is connected to an annunciator.

13. A relay device connected to a transmitting device and a receiving device that have each registered each other as a wireless communication destination in advance, for relaying wireless communication between the receiving device and the transmitting device, a receiving device search step of searching for a receiving device during the pairing mode, and receiving, from the receiving device detected by the search, receiving device connection information including receiving device address information that is address information of the receiving device and destination transmitting device address information that is address information of the transmitting device that has been registered as a connection destination in the receiving device; a transmitting device searching step of searching for a transmitting device during the pairing mode, and receiving, from the transmitting device detected by the search, transmitting device connection information including transmitting device address information which is address information of the transmitting device and destination receiving device address information which is address information of the receiving device which has been registered as a connection destination in the transmitting device; a control unit that executes a determination step of determining whether to transition from the pairing mode to a relay communication mode in which wireless communication between the receiving device and the transmitting device is relayed based on the receiving device address information received from the detected receiving device, the destination receiving device address information received from the detected transmitting device, the transmitting device address information received from the detected transmitting device, and the destination transmitting device address information received from the detected receiving device.

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