Wireless communication network system and wireless communication terminal

Abstract

To provide a system that can promptly switch the group formation / integration state from each wireless communication terminal in a simplex wireless communication network. [Solution] Each terminal belonging to each group Gx (x = a, b, c) sets the transmission and reception channels to chA / chB / chC when communicating in the group formation state, but when it enters standby mode, the receiver / demodulator RX enters scanning mode for chA / chB / chC / chZ (chZ is a common channel). If no signals are received on all scanned channels in this mode, the receiver / demodulator RX is set to chZ and it becomes possible to transmit an integrated signal. In this state, the receiver / demodulator RX of all terminals in the network is in scanning mode, and when it receives an integrated signal during the scanning phase of chZ, it switches its own transmission and reception channel to chZ, thereby transitioning to the group integration state. In this state, it is possible to transmit an organization signal via channel chZ and return to the group formation state as appropriate.

Description

[Technical Field]

[0001] The present invention relates to a network system and its wireless communication equipment that can switch between a group formation state in which there are multiple groups in which multiple wireless communication terminals perform simplex communication between them, and a group integration state in which the groups are integrated to enable simplex communication between wireless communication terminals in different groups, in a simplex wireless communication network composed of business wireless communication terminals such as those of a specific low-power standard. [Background technology]

[0002] Wireless communication devices that comply with the specified low-power standard (see Non-Patent Document 1 below) are used for voice communication over relatively short distances using the 400 MHz band, and are also license-free radio stations. As such, they are widely used for business-related communication between employees outdoors at various work sites such as construction sites, and indoors at relatively large restaurants and home improvement stores with ample space.

[0003] Furthermore, radio communication devices conforming to the digital simplex radio standard (see Non-Patent Document 2 below) are radio stations that can be established with a relatively simple application, and while the specified low-power standard allows for a maximum radio wave output of 10 mW, these devices are permitted for a maximum radio wave output of 5 W, which significantly increases the communication distance, making them suitable for use in large event venues and for communication between floors of high-rise buildings.

[0004] Generally, simplex communication is often adopted for wireless communication for business communication, and communication is maintained within a business group by repeating transmission and reception using a single channel. However, for example, at a construction site, it may be better to separate communication channels between the site supervisor and responsible person and communication channels between workers.Also, when guarding an exhibition venue, it is often more effective to divide the area and maintain close communication within each divided area, rather than using a single channel for overall communication throughout the entire area.

[0005] Therefore, the basic issue is how large the scope of group communication should be. Naturally, it is desirable to be able to switch between an operational state of multiple small communication groups (group organization state) and an operational state of a larger communication group that integrates these groups (group integration state) as appropriate. Such network operation is particularly required in preparation for situations where information needs to be shared through an emergency integrated communication network, such as in the event of an accident or disaster.

[0006] On the other hand, in the network using the simplex communication method for business communication mentioned above, as shown in Figure 14, if wireless communication terminals (101, 102, 103) and (201, 202, 203) belonging to groups G1 and G2 are conducting simplex communication on channels A and B, respectively, communication between the groups is not possible unless one group matches the channel it is using to the channel of the other group, and there is no way for the groups to communicate with each other. Furthermore, changing channels requires a complex communication sequence that takes time, and even if one terminal in group G1 changes its transmitting and receiving channel to channel B and becomes able to communicate with each terminal in group G2 using simplex communication, the other terminals in group G1 remain as they were and have no way of knowing about the situation.

[0007] Patent Document 1 below discloses a wireless communication method for reorganizing two ad-hoc wireless LANs into one integrated wireless LAN. In this wireless communication method, when any group A performs network communication, one of the wireless terminals aa belonging to that group becomes the group host, performs carrier sensing to check the channel used by one of the wireless terminals bb of another group B, and executes an information exchange procedure regarding whether or not the groups can be merged and the communication channel to be used by exchanging packets between the two wireless terminals aa and bb.If the groups can be merged and the communication channel to be used has been determined, each wireless terminal aa and bb notifies the other terminals of groups A and B, respectively, and has them set the determined communication channel, thereby starting equal-distributed network communication. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 10-135965 [Non-patent literature]

[0009] [Non-Patent Document 1] Association of Radio Industries and Businesses, "Specific Low-Power Radio Stations / Radio Equipment for Radio Telephones / Standard Specifications," RCR STD-20 Version 5.1, revised October 29, 2021 [Non-patent document 2] Association of Radio Industries and Businesses, "Radio Equipment for Digital Simple Radio Stations," ARIB STD-T98 Version 2.0, revised October 4, 2023 Summary of the Invention [Problem to be solved by the invention]

[0010] As described above, in group communications using wireless communication terminals that are used in many business fields, it is convenient to be able to switch between the operational state of a small communication group and the operational state of a large communication group that integrates those groups, and it is believed that this will enable rational operation that is suited to a variety of uses.

[0011] However, as with conventional methods, in order for one group to match its channel usage with the channel usage of another group, it must either know the channel usage of the other group in advance, or if it does not know, it must find out by scanning or the like.Even if it knows the channel usage, it must also notify other terminals in the group to which it belongs that they should change to that channel. Therefore, the procedures for merging and unmerging groups are quite complicated and time-consuming, and considering that this is often an emergency, it cannot be said to be user-friendly. In the wireless communication method of Patent Document 1, wireless terminals aa and bb execute the procedure on behalf of groups A and B, but there still remain problems in terms of responsiveness. Furthermore, while the above assumes the case of two communication groups, if three or more communication groups are to be integrated and then disintegrated, the procedure for carrying this out through prior communication becomes extremely complicated, and it is naturally impossible to expect quick response.

[0012] Therefore, taking the above problems into consideration, the present invention aims to provide a wireless communication network system and a wireless communication terminal that can be quickly switched between a group formation state in which multiple groups consisting of multiple wireless communication terminals communicate independently on a group-by-group basis using simplex communication, and a group integration state in which multiple groups are integrated into one and all wireless communication terminals communicate with each other using simplex communication. [Means for solving the problem]

[0013] A first invention is a wireless communication network capable of assuming a group formation state in which there are N groups (where N is an integer of 2 or more) in which a plurality of wireless communication terminals communicate in a simplex mode using one channel (hereinafter referred to as a "group channel"), with the N groups having different channels, and a group integration state in which all of the wireless communication terminals belonging to the N groups communicate in a simplex mode using a common channel, wherein the wireless communication terminals set a modulation / transmission unit and a reception / demodulation unit to the group channel of the group to which the wireless communication terminal belongs (hereinafter referred to as a "own group channel") during communication operation in the group formation state, but set the reception / demodulation unit to a scanning mode in which the reception / demodulation unit cyclically scans the own group channel, each group channel of other (N-1) groups, and the common channel at a predetermined period, in the group integration state, and a channel control means for setting the modulation / transmission unit and the reception / demodulation unit to the common channel in the scanning mode of the reception / demodulation unit; and instruction means for instructing mutual switching between the group formation state and the group integration state, wherein in the group formation state, if an instruction for switching is given from the instruction means while the state detection means is detecting the first state, the set channel of the modulation-transmission unit and the reception-demodulation unit is switched from the own group channel to the common channel and a group integration signal is generated and transmitted; if the state detection means detects the second state, the reception-demodulation unit is returned from the scanning mode to a set state of the own group channel; and if the group integration signal transmitted by another wireless communication terminal is detected from a received signal on the common channel while the state detection means is detecting the third state, the set channel of the modulation-transmission unit and the reception-demodulation unit is switched from the own group channel to the common channel;In accordance with the present invention, a wireless communication network system is characterized in that, after a group formation signal is generated and transmitted when a switching instruction is received from the instruction means, and immediately when the receiving and demodulating unit receives the group formation signal transmitted from another wireless communication terminal, the set channels of the modulating and transmitting unit and the receiving and demodulating unit are switched from the common channel to the channel of the group to which the terminal belongs, thereby executing switching between the group formation state and the group integration state of the network.

[0014] In the wireless communication network of the present invention, switching is performed between a group formation state in which N groups consisting of multiple wireless communication terminals each communicate in a simplex manner using a different group channel, and a group integration state in which all wireless communication terminals belonging to the N groups communicate in a simplex manner using a common channel.

[0015] In this case, when transitioning from the group formation state to the group integration state, it is necessary to send a group integration signal, which is a command signal, to all wireless communication terminals in the network. When each wireless communication terminal enters a standby state, it sets its receiving and demodulating unit to scanning mode and controls it to cyclically scan its own group channel, each group channel of the other (N-1) groups, and the common channel at a predetermined period. However, the predetermined period is set within a range in which the presence or absence of a received signal can be confirmed in each scanning target channel.

[0016] When the state detection means detects the first state in which no received signal is present on any of the scanned channels, all wireless communication terminals belonging to the N groups are in standby mode, and therefore the receiving and demodulating units of all wireless communication terminals other than the own terminal are also in scanning mode.

[0017] Here, when a switching instruction is given from the instruction means in the wireless communication terminal of a user who desires to communicate in the group integration state, the modulation transmission unit and reception demodulation unit in the terminal are set to the common channel, and a group integration signal is transmitted as a command signal from the modulation transmission unit. On the other hand, since the receiver / demodulator units of all other wireless communication terminals are in scanning mode as described above, they are able to receive the group unified signal during the scanning process of the common channel, and upon receiving this signal, they switch and set their own modulation / transmission units and receiver / demodulator units to the common channel.

[0018] As a result, all wireless communication terminals belonging to the N groups are set to a common channel, a group-integrated network is formed, and simplex communication using the common channel becomes possible between all wireless communication terminals. Therefore, from any of the wireless communication terminals belonging to the N groups, if the state detection means is detecting the first state, the group formation state can be transitioned to the group integration state simply by giving a switching instruction from the instruction means.

[0019] In addition, when the state detection means is in the second state, i.e., when there is a received signal from the own group channel and / or the group channels of other (N-1) groups in the scanning mode of the receiving and demodulating unit, it must be a state in which group communication is being carried out in a group formation state in one of the N groups.In this case, there is a group that cannot receive a group unified signal even if it is transmitted on a common channel, so the receiving and demodulating unit is returned from the scanning mode to the setting state of the own group channel to make it possible to communicate in a group formation state.

[0020] Furthermore, when the state detection means is in the third state, i.e., when a received signal is present on the common channel, if a group integration signal transmitted by another wireless communication terminal is detected from the received signal, the modulation / transmission unit and reception / demodulation unit of the terminal are switched and set to the common channel in accordance with the command, and in this case a network in a group integration state is formed based on the request of the other wireless communication terminal.

[0021] The above is related to the functions and operations of wireless communication terminals in a group formation state, but in a group integration state, all wireless communication terminals have set a common channel as a transmission and reception channel, and it is possible to issue and receive group formation instructions using the common channel as is. Therefore, when a switching instruction is given from the instruction means, the set transmission / reception channel is switched from the common channel to the own group channel immediately after the group formation signal is generated and transmitted, or when the reception / demodulation unit receives a group formation signal from another wireless communication terminal. As a result, all wireless communication terminals belonging to the N groups switch from a common channel setting state to a channel setting state for their own group, and the network transitions from a group integration state to a group organization state.

[0022] In the first invention, it is desirable that the cyclic scanning in the scanning mode by the channel control means is performed at a predetermined cycle in which the scanning time of the group channels belonging to the group is set sufficiently longer than the scanning time of each group channel of the other (N-1) groups and the scanning time of the common channel.

[0023] In the first invention, the scanning mode of the receiving and demodulating unit by the channel control means in the group formation state is started when the wireless communication terminal enters the standby state, but when there is reception on the own group channel, the receiving and demodulating unit is immediately switched from the scanning mode to the setting state of the own group channel and transitions to receiving the call signal in the own group. In this case, if the own group channel / each group channel of other groups / common channel is scanned cyclically at a predetermined cycle, depending on the timing of receiving the call signal, the scanning of the own group channel within the predetermined cycle may occur later than the scanning of other channels, causing the beginning of the call to be cut off. This problem can be effectively prevented by setting the scanning time of the group channel to be sufficiently longer than the scanning time of each of the other channels during the cyclic scanning period.

[0024] In the first invention, when the state detection means detects the second state, if there is a received signal on the group channel belonging to the same group, the receiving and demodulating unit is switched from the scanning mode to the setting state of the group channel belonging to the same group, but if there is a received signal only on group channels of other groups than the group channel belonging to the same group, it is desirable that the scanning mode of the receiving and demodulating unit is maintained and the state detection means returns to detecting the first state to the third state.

[0025] Since the received signal on the group channel to which it belongs relates to the call signal in the group to which it belongs, the receiving and demodulating unit must not be in scanning mode and must immediately return to the group channel to be able to carry out group communication. However, when there is a received signal only on the group channel of another group, this means that the group is in a group formation state and communication is being carried out only in the other group, and the group to which it belongs is in a standby state. At this time, no particular action is required, so the receiving and demodulating unit remains in the scanning mode and the process returns to the state detection operation. If there is no received signal on any of the loop channels, the third state is necessarily reached, and if a group unified signal is detected, the modulation / transmission unit and the reception / demodulation unit are switched to the common channel.

[0026] In the first invention, it is desirable that the wireless communication terminal is provided with a display means, and that in the group formation state, it displays that switching to the group integration state is possible while the state detection means is detecting the first state, and that in the group integration state, it displays that switching to the group formation state is possible during a period when the modulation / transmission unit and the reception / demodulation unit are set to the common channel.

[0027] In the first invention, it is possible to switch to the group integration state by giving an instruction from the instruction means during the time period when the state detection means detects the first state in the group formation state. However, it is difficult to determine whether the state detection means has detected the first state, for example, if the demodulated signal from the receiving demodulation unit in scanning mode changes over a short period of time, even if the demodulated signal changes. According to this method of displaying whether switching is possible or not, the display means can visually notify whether the state detection means is in the first state or not and whether a common channel is set or not, making it easier to confirm the timing of inputting an instruction to switch between the group formation state and the group integration state by the instruction means on the wireless communication terminal. As a display means, a method of turning on / off an indicator or a method of displaying the status on a display means can be applied.

[0028] The method of notifying the network status in the first aspect of the invention may also be a method of notifying by beep sound generation means. In this case, the wireless communication terminal is provided with a beep generating means, and in the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting the first state, the beep generating means generates and transmits the group integration signal and then outputs a first beep, while if a switching instruction is received from the instruction means while the state detection means is detecting a state other than the first state, the beep generating means immediately outputs a second beep, and also, in the group formation state, if a switching instruction is received from the instruction means, the wireless communication terminal is provided with a beep generating means and then outputs the first beep or a third beep, and it is desirable that the first to third beeps be different sounds from each other.

[0029] As with the case of the display means, this involves inputting an instruction to switch between the group formation state and the group integration state, but in this case, a beep will be sounded to notify whether the group integration signal / group formation signal has been transmitted properly. There are many cases where the state detection means frequently changes whether it is in the first state or not, and in such a situation, even if the occurrence of the first state is confirmed by the display means as described above, it is difficult to determine the timing to manually issue a switching instruction from the instruction means. In this beep notification method, when a switching instruction is received from the instruction means in a group formation state, the wireless communication terminal automatically checks whether or not it is detecting the first state, and notifies by outputting a first beep if the group integration signal can be transmitted, or a second beep if transmission is not possible. In the group integration state, if a carrier sense is performed and a transmission is possible, the group formation signal can be transmitted as is, and the first beep or the third beep is output after the transmission. The status can be easily confirmed by making each beep sound different from the others, for example, the first beep being a long beep, the second beep being multiple short beeps, and the third beep being a long beep with a different tone from the first beep.

[0030] In the first aspect of the present invention, the wireless communication terminal includes a counter, and when transmitting the group integration signal or the group organization signal, the counter value of the wireless communication terminal is incremented by a predetermined number and the incremented count value is added to the signal and transmitted. On the other hand, when the group integration signal or the group organization signal is received, the counter value (C1) added to the received group integration signal or the group organization signal is extracted and compared with the incremented count value (M) of the counter of the wireless communication terminal. If the count value (C1) is greater than the count value (M), the wireless communication terminal sets the modulation / transmission unit and the reception / demodulation unit to the common channel or the group channel to which the wireless communication terminal belongs in accordance with the received signal, and the count value (M) is added to the count value ( It is desirable that, when transmitting a communication signal related to a call, the count value of the counter of the own device is always added to the communication frame and transmitted, and, when receiving a communication frame from another wireless communication terminal, the count value (C2) added to the communication frame is extracted and compared with the count value (M) of the counter of the own device, and, when the count value (C2) > the count value (M), the count value (M) of the counter is rewritten to the count value (C2), while, when the count value (C2) ≦ the count value (M), the count value (M) of the counter is maintained as is.

[0031] In the first invention, a wireless communication terminal belonging to a wireless communication network switches the network between a group integration state and a group integration state by transmitting a group integration signal when in a group formation state and a group formation signal when in a group integration state, respectively. However, each wireless communication terminal is not always within the communication range of other wireless communication terminals, and there are cases where a terminal goes out of range and then returns, or where the power is turned off for a certain period of time. In such cases, there will be wireless communication terminals whose transmission and reception channels are set to common channels even though the network is in a group-organized state, or conversely, wireless communication terminals whose transmission and reception channels are set to their own group channels even though the network is in a group-integrated state. To address such inconsistencies, a dedicated counter is provided in each wireless communication terminal, and each time a group formation state / group integration state switching signal (group integration signal or the group formation signal) is transmitted, the count value is first incremented by a predetermined number to update it, and the updated count value of the counter of the terminal is always added to the communication frame of the switching signal or communication signal related to the call before transmission. Furthermore, it can be estimated that the more channel changes each wireless communication terminal has undergone (i.e., the larger the counter value), the more likely it is that its channel setting state (own group channel / common channel) corresponds to the current channel setting state of the network. Therefore, each time a switching signal is received, the count value (C1) attached to the signal is compared with the count value (M) of the counter of the device itself, and if C1>M, the device switches its transmitting and receiving channels to the common channel or the group channel to which it belongs, depending on whether the received switching signal is a group integration signal or a group organization signal. Also, when a communication signal related to a call is received, the count value (C2) attached to the communication frame is compared with the count value (M) of the counter of the device itself. However, since the communication is on the own group channel in this case, the channel is not switched, and if C2>M, the count value (M) of the counter of the device itself is simply rewritten to the count value (C2). If C1≦M and C2≦M, no action is taken and the current situation is maintained. As a result, even if a wireless communication terminal that has temporarily left the communication range or has been turned off for a certain period of time no longer corresponds to the communication state (group formation state / group integration state) on the network side, it can automatically respond to the current network communication state by returning to the communication range or turning the power back on.

[0032] A second aspect of the present invention relates to a wireless communication terminal that is applied to the wireless communication network system of the first aspect of the present invention, and has the following configuration. A wireless communication terminal applied to a wireless communication network capable of assuming a group formation state in which there are N groups (where N is an integer of 2 or more) in which a plurality of wireless communication terminals communicate in a simplex mode using one channel (hereinafter referred to as a "group channel"), each group having a different one channel, and a group integration state in which all wireless communication terminals belonging to the N groups communicate in a simplex mode using a common channel, the wireless communication terminal comprising: channel control means for setting a modulation / transmission unit and a reception / demodulation unit to the group channel of the group to which the terminal belongs (hereinafter referred to as an "own group channel") during communication operation in the group formation state, and setting the reception / demodulation unit to a scanning mode in which the reception / demodulation unit cyclically scans the own group channel, each group channel of other (N-1) groups, and the common channel at a predetermined cycle during standby operation, and setting the modulation / transmission unit and the reception / demodulation unit to the common channel in the group integration state; and channel control means for setting the modulation / transmission unit and the reception / demodulation unit to the common channel in the scanning mode of the reception / demodulation unit, and instruction means for instructing mutual switching between the group formation state and the group integration state, wherein in the group formation state, if an instruction for switching is given from the instruction means while the state detection means is detecting the first state, the set channel of the modulation-transmission unit and the reception-demodulation unit is switched from the own group channel to the common channel and causes a group integration signal to be generated and transmitted, and when the state detection means detects the second state, the reception-demodulation unit is switched from the scanning mode to a set state of the own group channel, and when the state detection means detects the group integration signal transmitted by another wireless communication terminal from a received signal on the common channel while the state detection means is detecting the third state, the set channel of the modulation-transmission unit and the reception-demodulation unit is switched from the own group channel to the common channel,a wireless communication terminal that, after generating and transmitting a group organization signal when a switching instruction is received from the instruction means, and immediately when the receiving and demodulating unit receives the group organization signal transmitted by another wireless communication terminal, switches the set channel of the modulation and transmitting unit and the receiving and demodulating unit from the common channel to the channel of the group to which the wireless communication terminal belongs,

[0033] In the wireless communication terminal of the second invention, it is desirable to configure the cyclic scanning in the scanning mode by the channel control means to be performed at a predetermined cycle in which the scanning time of the group channels belonging to the own group is set sufficiently longer than the scanning time of each group channel of the other (N-1) groups and the scanning time of the common channel.

[0034] In the wireless communication terminal of the second invention, when the state detection means detects the second state and there is a received signal on the own group channel, the receiving and demodulating unit is switched from the scanning mode to the setting state of the own group channel, but when there is a received signal only on group channels of groups other than the own group channel, it is desirable that the scanning mode of the receiving and demodulating unit is maintained and the state detection means returns to detecting the first state to the third state.

[0035] Furthermore, in the wireless communication terminal of the second invention, it is desirable to provide a display means that displays that in the group formation state, switching to the group integration state is possible while the state detection means is detecting the first state, and that in the group integration state, switching to the group formation state is possible during the period when the modulation / transmission unit and the reception / demodulation unit are set to the common channel.

[0036] Furthermore, in the wireless communication terminal of the second invention, it is preferable that the wireless communication terminal further comprises beep generating means, and when in the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting the first state, the beep generating means generates and transmits the group integration signal and then outputs a first beep, while when a switching instruction is received from the instruction means while the state detection means is detecting a state other than the first state, the beep generating means immediately outputs a second beep, and when in the group formation state, if a switching instruction is received from the instruction means, the wireless communication terminal further generates and transmits the group formation signal and then outputs the first beep or a third beep, and that the first to third beeps are mutually different sounds.

[0037] Furthermore, in a wireless communication terminal according to a second aspect of the present invention, a counter is provided, and when transmitting the group integration signal or the group formation signal, the count value of the counter of the terminal itself is incremented by a predetermined number and the incremented count value is added to the signal and transmitted. On the other hand, when the group integration signal or the group formation signal is received, the count value (C1) added to the received group integration signal or the group formation signal is extracted and compared with the incremented count value (M) of the counter of the terminal itself. If the count value (C1) is greater than the count value (M), the modulation / transmission unit and the reception / demodulation unit and sets the modulation / transmission unit to the common channel or the own group channel according to the received signal, and rewrites the count value (M) to the count value (C1), while maintaining the set channels of the modulation / transmission unit and the reception / demodulation unit as they are if the count value (C1) is equal to or less than the count value (M), and when transmitting a communication signal related to a call, always adds the count value of the counter of the own device to the communication frame and transmits it, while when receiving a communication frame from another wireless communication terminal, extracts the count value (C2) added to the communication frame and compares it with the count value (M) of the counter of the own device, and when the count value (C2) > the count value (M), rewrites the count value (M) of the counter to the count value (C2), while when the count value (C2) is equal to or less than the count value (M), maintains the count value (M) of the counter as it is. [Effects of the Invention]

[0038] According to the wireless communication network system and wireless communication terminal of the present invention, it is possible to switch between a group organization state in which there are multiple groups in which simplex communication is carried out between multiple wireless communication terminals, and a group integration state in which all groups are integrated to enable simplex communication even between wireless communication terminals in different groups, by performing an instruction operation from any wireless communication terminal. Each wireless communication terminal that makes up the network can be configured with the same specifications in terms of hardware, as it requires only a standard basic configuration with a pair of modulation / transmission units and a reception / demodulation unit.On the other hand, in terms of software, the only difference is the group channel, and the control sequence can be standardized, which has the advantage that it is relatively easy to build a network system. [Brief explanation of the drawings]

[0039] [Figure 1] 1 is a functional block diagram of a wireless communication terminal applied to an embodiment of the present invention. [Figure 2] This is a schematic diagram of a network in a group formation state in which wireless communication terminals belonging to three groups Ga, Gb, and Gc are performing simplex communication in groups Ga and Gc, and are in a standby state in group Gb. [Figure 3] This is a schematic diagram of a network in a group integration state (in the figure, wireless communication terminal 50c-2 is the transmitting terminal and the others are receiving terminals) in which three groups Ga, Gb, and Gc are integrated and simplex communication can be performed between each wireless communication terminal within the network. [Figure 4] FIG. 10 is a diagram schematically illustrating a channel cyclic scanning state performed in a scanning mode by the reception and demodulation units RX of the wireless communication terminals 50a, 50b, and 50c belonging to groups Ga, Gb, and Gc. [Figure 5] 1 is a diagram illustrating an example of a communication frame format used in a wireless communication network according to an embodiment. [Figure 6A] 5 is a flowchart showing an operation procedure of each wireless communication terminal applied to the wireless communication network system according to the first embodiment. [Figure 6B] 6 is a flowchart showing an operation procedure (modification of the process in step S22 of FIG. 6A) of each wireless communication terminal applied to the wireless communication network system according to the first embodiment. [Figure 7] FIG. 10 is a schematic diagram of a network in a group formation state in which each wireless communication terminal belonging to three groups Ga, Gb, and Gc is in a standby state in each group. [Figure 8]FIG. 8 is a schematic network diagram showing a transition instruction stage from the group formation state of FIG. 7 in which a wireless communication terminal 50a-2 belonging to group Ga has transmitted a group unification signal. [Figure 9] FIG. 10 is a schematic diagram of a network in a group integration state in which each wireless communication terminal is in a standby state after three groups Ga, Gb, and Gc have been integrated. [Figure 10] FIG. 10 is a network schematic diagram showing a transition instruction stage from the group integration state of FIG. 9 in which a wireless communication terminal 50a-2 belonging to group Ga has transmitted a group formation signal. [Figure 11] 10 is a flowchart showing an operation procedure of the wireless communication terminal according to the second embodiment. [Figure 12A] 10 is a flowchart showing an operation procedure (mainly a procedure for transitioning from a group formation state to a group integration state) of a wireless communication terminal according to a third embodiment. [Figure 12B] 10 is a flowchart showing an operation procedure (mainly a procedure for transitioning from a group integration state to a group organization state) of a wireless communication terminal according to a third embodiment. [Figure 12C] 10 is a flowchart showing an operation procedure of the wireless communication terminal according to the third embodiment. [Figure 13A] 10 is a flowchart showing an operation procedure (mainly a procedure for transitioning from a group formation state to a group integration state) of a wireless communication terminal according to a third embodiment. [Figure 13B] 10 is a flowchart showing an operation procedure (mainly a procedure for transitioning from a group integration state to a group organization state) of a wireless communication terminal according to a third embodiment. [Figure 14] FIG. 1 is a schematic diagram of a network showing a conventional simplex communication state for each group. DETAILED DESCRIPTION OF THE INVENTION

[0040] Hereinafter, embodiments of a wireless communication network system and a wireless communication terminal of the present invention will be described with reference to FIGS. 1 to 13B. First, FIG. 1 is a functional block diagram of business wireless communication terminals 50a, 50b, and 50c according to an embodiment, in which 20 is an antenna, 21 is a distributor, 22 is an amplifier, RX is a receiving and demodulating unit, 23 is an amplifier, 24 is a speaker (or earphone), 25 is a microphone, 26 is an amplifier, TX is a modulation transmitting unit, 27 is an amplifier, 28 is a system control unit, 29 is an operation unit, 30 is an LCD display unit, and 31 is a buzzer.

[0041] In the receiving system, the received signal from the antenna 20 is input to the receiving demodulation unit RX via the distributor 21 and amplifier 22, where only the signal of the set channel is extracted and demodulated from the received signal. The demodulated signal is then amplified by the amplifier 23 and reproduced as audio from the speaker (or earphone) 24. In addition, in the transmission system, an input signal from a microphone 25 is input to a modulation transmission unit TX via an amplifier 26, where the carrier signal of the set channel is modulated with the input signal, and the modulated signal is power-amplified by an amplifier 27 and transmitted from an antenna (shared with the receiving system) 20 via a distributor 21.

[0042] The entire system as a wireless communication terminal including the reception and transmission systems is controlled by a system control unit 28. The system control unit 28 receives various instruction input signals from the operation unit 29 and signals from each module, controls the receiver / demodulator unit RX, the modulator / transmitter unit TX, and each amplifier 23, 26, reads out and transmits the group integration signal and the group organization signal to the modulator / transmitter unit TX, and also performs display control to display various information related to the communication status on the liquid crystal display unit 22 and control to sound a beep from the buzzer 31 as appropriate.

[0043] The wireless communication terminals 50a, 50b, and 50c of this embodiment are controlled so that a group organization state is formed in which groups Ga, Gb, and Gc are formed to perform simplex communication between wireless communication terminals using different communication channels chA, chB, and chC, as shown in Figure 2, and a group integration state is formed in which all groups Ga, Gb, and Gc are integrated, as shown in Figure 3, so that simplex communication is possible between wireless communication terminals of different groups using a common channel chZ. In each figure, the wireless communication terminals 50a, 50b, and 50c are represented by simplified blocks. For example, TX:chA indicates a state in which the modulation transmitting unit TX is set to channel chA, RX:chA indicates a state in which the receiving demodulation unit RX is set to channel chA, and RX:SCAN indicates a state in which the receiving demodulation unit RX is set to channel scanning mode.

[0044] In the group formation state, as shown in FIG. 2, the wireless communication terminals 50a-1 to 50a-3 belong to group Ga, the wireless communication terminals 50b-1 to 50b-3 belong to group Gb, and the wireless communication terminals 50c-1 to 50c-3 belong to group Gc, and simplex communication can be performed for each group Ga, Gb, and Gc using their respective group channels chA, chB, and chC. In the group integration state, as shown in FIG. 3, the transmission and reception channels of all the wireless communication terminals 50a-1 to 50b-1 to 50b-3, and 50c-1 to 50c-3 are set to the common channel chZ, and simplex communication can be performed from each terminal to other terminals across groups.

[0045] However, in the group formation state of Figure 2, groups Ga and Gc are in communication (50a-2 and 50c-1 are transmitting terminals, and 50a-1, 2 and 50c-2, 3 are receiving terminals), while in group Gb, all wireless communication terminals 50b-1 to 3 are in standby mode, and in the group integration state of Figure 3, wireless communication terminal 50c-2 is the transmitting terminal, and the other wireless communication terminals 50a-1 to 3, 50b-1 to 3, 50c-1, 3 are receiving terminals.

[0046] Meanwhile, when there is no communication on group channel chB in a group formation state, as in group Gb in Figure 2, and each wireless communication terminal 50b-1 to 50b-3 enters a standby state, the system control unit 28 of each terminal switches the receiving demodulation unit RX from the group channel chB setting state to scanning mode. In the scanning mode of the wireless communication terminals 50b-1 to 50b-3 belonging to this group Gb, the system control unit 28 repeatedly switches the receiving channel of the receiving and demodulating unit RX in the order of group channel chB → group channel chA → group channel chC → common channel chZ, and cyclically scans each of the channels to check for the presence or absence of a received signal.

[0047] The above describes the conditions for transitioning to scanning mode and the scanning operation using each wireless communication terminal 50b-1 to 3 of group Gb in a group formation state as an example, but the same applies to each wireless communication terminal 50a-1 to 3, 50c-1 to 3 of groups Ga and Gc in a group formation state. However, the scanning order of each channel in scanning mode and the allocation of scanning time to each channel within one cyclic scanning cycle differ depending on which group the wireless communication terminal belongs to. For example, if one cyclic scanning cycle is 1 second, the allocation of scanning time to each channel for wireless communication terminals 50a-1 to 3, 50b-1 to 3, and 50c-1 to 3 of groups Ga, Gb, and Gc will be as shown in Figure 4.

[0048] As can be seen from the figure, within one scanning cycle (1 sec), the scanning time for the group channels chA / chB / chC to which the device belongs is allocated at a sufficiently long 910 msec, while the scanning time for other group channels and the scanning time for the common channel chZ is allocated at a short 30 msec. As will be seen in the embodiment described later, when a wireless communication terminal enters standby mode in a group formation state, it switches to scanning mode and executes a procedure for transitioning to a group integration state on the condition that there are no received signals on all scanning channels in that scanning mode.However, if there is a reception on the group channel to which the terminal belongs, it immediately returns to the receiving channel setting in the group formation state and plays back audio.This is why the scanning time on the group channel to which the terminal belongs is made as long as possible, and a measure is adopted to prevent the beginning of the received audio from being cut off.

[0049] Moreover, each of the wireless communication terminals 50a-1 to 50a-3, 50b-1 to 50b-3, and 50c-1 to 50c-3 according to the embodiment performs communication using a communication frame having a configuration as shown in FIG. 5 as an example. The transmitting terminal transmits a modulated wave modulated by MSK (Minimum Shift Keying) or the like using the baseband signal of the audio signal section incorporated in the frame format, and the receiving terminal demodulates the received signal related to the modulated wave to reproduce the audio signal, while each information signal of the data payload received prior to the audio signal is separated and detected and used as data for operational control by the system control unit 28. In addition to the usual information such as the device's own identification information (ID), the group identification information (G-ID) to which the device belongs, and transmission / reception channel information, the data payload also contains specific information such as the group formation signal (GFS) / group integration signal (GIS) and counter count value information.

[0050] Next, as first to third embodiments, a description will be given of switching between the group formation state and the group integration state of the wireless communication network and the operation procedures of the wireless communication terminals 50a-1 to 50a-3, 50b-1 to 50b-3, and 50c-1 to 50c-3. However, when explaining the relationship between the operation of a wireless communication terminal and the state of the wireless communication network, it is easier to understand if it is considered as the operation of one wireless communication terminal arbitrarily selected from wireless communication terminals 50a-1 to 3, 50b-1 to 3, and 50c-1 to 3.Therefore, in the flowchart relating to the operational procedure, the selected one terminal is referred to as "wireless communication terminal 50," the group to which wireless communication terminal 50 belongs is represented as Gx (x = a, b, c), and the group channel of group Gx is represented as chX (X = A, B, C). When the state of the wireless communication network is specifically explained in relation to each wireless communication terminal using a network schematic diagram, each wireless communication terminal will be indicated by an individual reference symbol.

[0051] <Embodiment 1> FIG. 6A is a flowchart showing the operation procedure of the wireless communication terminal 50 belonging to group Gx (group channel chX). First, the network is in a group formation state as shown in FIG. 2, and the wireless communication terminal 50 appropriately executes communication using the group channel chX in the group Gx, but the group communication may be interrupted and the terminal may enter a standby state. In the wireless communication terminal 50 according to this embodiment, when it is confirmed that the terminal has entered standby mode, the receiving and demodulating unit RX is switched from the group channel chX setting state to scanning mode [see FIG. 4] (S1, S2, S3:Y→S4).

[0052] In this scanning mode, the receiving and demodulating unit RX checks whether there are no received signals on all scanning channels chA, chB, chC, and chZ, and if this state is confirmed, the liquid crystal display unit 30 displays that it is possible to switch to the group integration state (S5: Y → S6). This display is intended to indicate the timing at which the ON operation of the GI / GF button, which will be described later, becomes effective, and is not limited to being displayed as text on the liquid crystal display unit 30, but may also be displayed by lighting an indicator lamp or the like. In this case, if there are no signals received on all scanning channels chA, chB, chC, and chZ by the receiving and demodulating unit RX, this means that all wireless communication terminals 50a-1 to 3, 50b-1 to 3, and 50c-1 to 3 in each group Ga, Gb, and Gc are in standby mode, as shown in Figure 7, and their receiving and demodulating units RX are set to scanning mode.

[0053] Here, unless the GI / GF button (an instruction button for switching between group formation state and group integration state) on the operation unit 29 is turned ON, the confirmation of the no-signal state and the above display continue (S7: N → S5, S6), but when the GI / GF button is turned ON, the modulation transmission unit TX and the reception demodulation unit RX are immediately switched and set to the common channel chZ, and the group integration signal (GIS) is set in a communication frame (not including an audio signal) and transmitted on the common channel chZ (S7: Y → S8, S9). Furthermore, the display (S6) on the liquid crystal display unit 30 is erased (S10) by transmitting the group integration signal (GIS).

[0054] FIG. 8 shows, as an example, a state in which the wireless communication terminal 50a-2 of group Ga transmits a group integrated signal (GIS) on the common channel chZ. At this stage, the receiving and demodulating units RX of all wireless communication terminals 50a-1, 50b-1 to 50c-1 to 50c-3 other than the wireless communication terminal 50a-2 are in scanning mode, so that the group integrated signal (GIS) transmitted by the wireless communication terminal 50a-2 can be received during the scanning stage of the common channel chZ. Therefore, upon receiving the group integration signal, the wireless communication terminals 50a-1, 50b-1 to 50c-1 to 50c-3 switch and set their modulation transmission units TX and reception demodulation units RX to the common channel chZ, and as a result, as shown in Figure 9, the transmission and reception channels of all wireless communication terminals 50a-1 to 50b-1 to 50c-1 to 50c-3 of groups Ga, Gb, and Gc become the common channel chZ, and the network transitions from a group formation state to a group integration state.

[0055] On the other hand, returning to FIG. 6A, if there is a received signal in the scan immediately after the receiver / demodulator unit RX of the wireless communication terminal 50 enters the scanning mode (S4, S5:N), or if there is no received signal at the time of the scan but there is a received signal while the GI / GF button is not turned ON (S4, S5:Y → S6, S7 → S5:N), the display (S6) is erased (only if S21: S6, S7 has been passed), and the following control is executed depending on whether there is a received signal in at least one of the group channels chA, chB, chC during the scanning process or there is a received signal in the common channel.

[0056] When there is at least one received signal on the group channel, communication is being carried out on the group channel in at least one of groups Ga, Gb, and Gc, and the receiving and demodulating unit RX is returned from the scanning mode to the setting state of group channel chA to correspond to the group organization state of the network (S22 → S26 → S1).

[0057] Regarding the procedure when there is a received signal on at least one group channel among all the scanned channels (step S22), instead of uniformly returning the receiving and demodulating unit RX from the scanning mode to the setting state of the group channel chX as shown in FIG. 6A to correspond to the group formation state, as shown in FIG. 6B, when there is a received signal related to the group channel of the group to which the own unit belongs, it corresponds to the group formation state in the same manner as above (S22-1: Y → S26 → S1), but when there is a received signal only on the group channel of another group, it is also possible to maintain the scanning mode of the receiving and demodulating unit RX and return to the procedure of checking whether there is a state in which there is no received signal on all the scanned channels (S22-2: Y → S5).

[0058] On the other hand, when there is a received signal on the shared channel, it is highly likely that a group integrated signal (GIS) is being transmitted from another wireless communication terminal in the network, and when this signal (GIS) is detected, the modulation transmission unit TX and the reception demodulation unit RX are switched and set to the common channel chZ (S23, S24, S25). This operation corresponds to the operation of the wireless communication terminals 50a-1, 50a-3, 50b-1 to 50b-3, and 50c-1 to 50c-3 other than the wireless communication terminal 50a-2 in the state shown in FIG. If the group integration signal (GIS) cannot be detected, it means that an unknown signal is being received, so in this case too, the receiving and demodulating unit RX is returned from the scanning mode to the setting state of the group channel chA to correspond to the group organization state of the network (S24 → S26 → S1).

[0059] Next, when the network enters a group integration state, as shown in Figures 3 and 9, the transmission and reception channels of all wireless communication terminals 50a-1 to 3, 50b-1 to 3, and 50c-1 to 3 in the network are unified into the common channel chZ, so that any terminal can communicate with other terminals using the common channel in a simplex manner. Therefore, returning to FIG. 6A, when the wireless communication terminal 50 enters the group integration state, the liquid crystal display unit 30 displays a message indicating that switching to the group organization state is possible (S12).

[0060] Then, in the wireless communication terminal 50, regardless of whether communication on the common channel chZ is in progress or not, when a user who desires to return to communication in a group formation state turns on the GI / GF button, if communication is in progress, a group formation signal (GFS) is set in the communication frame of a call signal and transmitted, and if the terminal is in a standby state, a transmission mode is set and a group formation signal (GFS) is set in a communication frame without a call signal and transmitted (S13, S14: Y → S15). Furthermore, when a group formation signal (GFS) is transmitted, after the transmission, the modulation transmission unit TX and reception demodulation unit RX of the own device are switched and set to the group channel chX (S16).

[0061] On the other hand, in the wireless communication terminal 50 in the group integration state, contrary to the transmission operation of the group formation signal (GFS) described above, the receiving and demodulating unit RX may receive and detect a group formation signal (GFS) from another wireless communication terminal on the common channel chZ (S31). This group formation signal (GFS) is set in a communication frame of a speech signal or a communication frame without a speech signal, and when it is received and detected, the modulation transmission unit TX and reception demodulation unit RX of the own device are switched and set to group channel chA in the same manner as described above (S31 → S16).

[0062] In either case, the modulation transmission unit TX and reception demodulation unit RX of the wireless communication terminal 50 are switched from the shared channel chZ to the group channel chA, and if such switching is set, the display in step S12 is erased (S16, S17), and the operation returns to the group formation state (S17 → S1).

[0063] FIG. 10 shows, as an example, a state in which a group formation signal (GFS) is being transmitted from the wireless communication terminal 50a-2 in the group integration state. Since the transmission and reception channels of all wireless communication terminals 50a-1 to 3, 50b-1 to 3, and 50c-1 to 3 in the network are the common channel chZ, the group formation signal (GFS) is received by all terminals except for wireless communication terminal 50a-2, and as a result, the transmission and reception channels of all wireless communication terminals 50a-1 to 3, 50b-1 to 3, and 50c-1 to 3 are switched to the group channel to which they belong and return to the group formation state.

[0064] <Embodiment 2> In the first embodiment, as shown in the flowchart of FIG. 6A, when the network is in a group formation state and the wireless communication terminal 50 is in a standby state, the receiving and demodulating unit RX is switched to a scanning mode (S3:Y→S4). In the channel cyclic scanning by the receiving and demodulating unit RX shown in FIG. 4, when there is no received signal on all scanning channels chA, chB, chC, chZ, that is, when it is time to transmit a group integration signal (GIS) on the common channel chZ, the liquid crystal display unit 30 displays that it is possible to switch to the group integration state based on the detection event of this no-signal state. Furthermore, when the network enters the group integration state, the liquid crystal display unit 30 displays a message indicating that it is possible to switch to the group organization state (S11, S12).

[0065] In the group formation state, the GI / GF button on the operation unit 29 is turned ON at the timing mentioned above, the transmission / reception channel is switched to the common channel chZ, and a group integration signal (GIS) is transmitted, and the above-mentioned display is erased (S7:Y→S8, S9, 10). In the group integration state, when the GI / GF button on the operation unit 29 is turned ON and a group formation signal (GFS) is transmitted, or when the group formation signal (GFS) is received / detected by the reception demodulation unit RX, the transmission / reception channel is switched from the common channel chZ to the group channel chX (S14, S15→S16 / S31→S16), and thereafter the above-mentioned displays are erased (S17).

[0066] In contrast to this, in the second embodiment, the operation of the wireless communication terminal 50 is controlled as shown in the flowchart of FIG. First, when the network is in a group formation state, if the wireless communication terminal 50 enters a standby state, the reception / demodulation unit RX is switched to the scanning mode, as in the first embodiment (S51 to S54). However, in this embodiment, any ON operation of the GI / GF button is allowed after the scanning mode is started, and if the channel cyclic scanning of the receiving and demodulating unit RX at the stage when the ON operation is performed confirms that there are no received signals on all scanning channels chA, chB, chC, and chZ, the modulating and transmitting unit TX and receiving and demodulating unit RX are switched from the group channel chX to the common channel chZ and a group integrated signal (GIS) is transmitted, and then the buzzer 31 is driven to output one long beep (S55, S56: Y → S57 to S58, S59). That is, the user is notified that the transmission of the group integration signal (GIS) accompanying the ON operation of the GI / GF button has been executed at a valid timing.

[0067] Conversely, if it is confirmed that there is a received signal on at least one of all the scanning channels chA, chB, chC, and chZ when the GI / GF button is turned ON, the buzzer 31 is activated to output several short beeps (S55, S56: N → S71). In other words, if there is any other wireless communication terminal that cannot receive the group integration signal (GIS) at the timing of the ON operation, the group integration signal (GIS) cannot be transmitted effectively, and therefore the user is immediately notified that the ON operation is invalid.

[0068] In addition, after the short beep sound has been output several times, or when there is a received signal in at least one group channel among all the scanned channels of the receiving and demodulating unit RX or when there is a received signal in the common channel chZ while the GI / GF button is not turned ON, the operation is the same as in embodiment 1 (S71 → S72 to S75 / S55:N → S55a:N → S72 to S75). Furthermore, when there is a received signal on at least one group channel among all the scanned channels, as shown in FIG. 6B of embodiment 1, the operation of returning to the setting state of group channel chX or the operation of maintaining the scanning mode may be selected depending on whether or not the received signal includes the group channel of the device itself [(S22-1: Y → S26 → S1) / (S22-2: Y → S5) in FIG. 6B].

[0069] On the other hand, when the network is in a group integration state, if no other wireless communication terminals are in a transmitting state (if they are in an idle state by carrier sense), the GI / GF button can be turned ON at any time to transmit a group formation signal (GFS), and when that signal is transmitted, the buzzer 31 is activated to output one long beep (S62 to S64). As with the transmission of the group integration signal (GIS), this also notifies the user that the transmission of the group formation signal (GFS) in response to the ON operation of the GI / GF button has been successfully executed, but since it involves the transmission of a different signal, it is desirable to make it audibly distinguishable from the beep sound that occurs when the group integration signal (GIS) is transmitted.

[0070] As described above, this embodiment 2 (FIG. 11) is characterized by the procedure for notifying whether or not a group integration signal (GIS) / group formation signal (GFS) corresponding to the ON operation of the GI / GF button can be transmitted and the completion thereof. In relation to embodiment 1 (FIGS. 6A and 6B), the only difference is that the procedure for displaying / erasing on the liquid crystal display unit 30 that indicates that transmission of each of the above signals is possible in embodiment 1 has been replaced with these characteristic procedures, and therefore other operational procedures are the same as in embodiment 1.

[0071] <Embodiment 3> In the wireless communication network systems described in the first and second embodiments, each wireless communication terminal 50a-1 to 3, 50b-1 to 3, 50c-1 to 3 belonging to the network transmits a group integration signal / group organization signal, which are command signals, in the group organization state / group integration state, respectively, thereby enabling the state of the network to be switched appropriately. However, it is inevitable that there will be wireless communication terminals that temporarily go out of the communication range or that have their power turned off for a certain period of time for various reasons.

[0072] However, if a group integration signal / group formation signal is sent and received during a time when the wireless communication terminal is out of the communication range or is turned off, causing the group formation state / group integration state to switch, even if the wireless communication terminal returns to its original state, a state may occur in which the transmission and reception channel is set to a common channel even though the network is in a group formation state, or conversely, a state in which the transmission and reception channel is set to a group channel even though the network is in a group integration state, resulting in a so-called ``stray terminal.''

[0073] In this embodiment 3, each wireless communication terminal 50 is provided with a counter, which records and stores the number of times the group formation state / group integration state has been switched over. When a group integration signal / group formation signal is transmitted, the count value of the counter of the terminal itself is added to the signal. When a group integration signal / group formation signal is received, the count value added to the signal is compared with the count value of the terminal itself. If the wireless communication terminal 50 is a stray terminal, the transmitting and receiving channels are adaptively rewritten and set, thereby realizing an automatic return function according to the state of the network (hereinafter referred to as the "matching return function of the stray terminal").

[0074] The procedures for this purpose are incorporated into the basic procedures (FIG. 6A) of the wireless communication terminal 50 of embodiment 1 as shown in FIGS. 12A, 12B, and 12C, and the procedures for this purpose are incorporated into the basic procedures (FIG. 11) of the wireless communication terminal 50 of embodiment 2 as shown in FIGS. 13A, 13B, and 12C.

[0075] Figure 12A is a flowchart that incorporates the necessary procedures related to the matching recovery function of a deviated terminal, with the basic operating procedures being the procedures (S1 to S10) from the group formation state in Figure 6A to the transmission of a group integration signal (GIS) and the procedure (S5 → S21 to S26) for switching the transmission and reception channel to the common channel chZ when the receiving and demodulating unit RX receives the group integration signal (GIS) in scanning mode.

[0076] FIG. 12A differs from FIG. 6A (S1 to S10, S5 → S21 to S26) in that, when transmitting a group integration signal (GIS), the count value of the counter of the device itself is incremented by 1, and the incremented count value is added to the group integration signal (GIS) and transmitted (S9-1, S9-2). In this embodiment, as described above, a count value is added to the group integration signal (GIS) before transmission. Therefore, when the device receives or detects the group integration signal (GIS), the device compares the received count value Q with the count value M of the counter of the device itself (S24-1: Y → S24-2). If Q>M, the device switches its transmission / reception channel to the common channel chZ, and rewrites the counter count value M to Q (S24-3: Y → S25-1, S25-2). On the other hand, if Q≦M, the device maintains the current transmission / reception channel chX (S24-3: N → S24-4 → S26 → S1).

[0077] Figure 12B is a flowchart that incorporates the necessary procedures related to the matching restoration function of the deviated terminal, based on the basic operating procedures of sending a group integration signal (GIS) from the group integration state in Figure 6A to switch the transmission / reception channel to group channel chX (S11 to S16) and switching the transmission / reception channel to group channel chX when a group formation signal (GFS) is received without the GI / GF button being turned ON (S14: N → S31: Y → S16).

[0078] FIG. 12B differs from FIG. 6A (S11 to S16, S14: N → S31: Y → S16) in that, when transmitting a group formation signal (GFS), the count value of the counter of the device itself is incremented by 1 and the incremented count value is added to the group formation signal (GFS) and transmitted (S15-1, S15-2). In this embodiment, a count value is added to the group formation signal (GFS) and transmitted, so when the device receives or detects the GFS, the received count value R is compared with the count value M of the device's counter (S31-1: Y → S31-2). If R>M, the counter count value M is rewritten to R, and the device's transmission / reception channel is switched to group channel chX (S31-3: Y → S31-4 → S16). However, if R≦M, the current transmission / reception channel chZ is maintained (S31-3: N → S31-4 → S13).

[0079] Furthermore, in this embodiment 3, even when the wireless communication terminal 50 is communicating using the group channel chX or the common channel chZ (S2 in FIG. 12A or S13 in FIG. 12B), the wireless communication terminal 50 always adds the count value of its own counter to the communication frame and transmits it, and when it receives the communication frame, it executes the operation procedure of FIG. 12C. Specifically, when a call communication frame is received, the count value W of the counter of the transmitting terminal, which is additionally recorded in the data payload of the frame, is detected, and the detected count value W is compared with the count value M of the counter of the own terminal (S101 to S103). If the comparison result is W>M, the count value M is rewritten to W, and conversely, if W≦M, the count value M is maintained as is (S104, S105).

[0080] During this communication phase, the process of correcting / maintaining the counter count value is carried out when the wireless communication terminals are communicating on the same channel (group channel chX or common channel chZ), and the transmission / reception channel is not switched even if the count value W and the count value M differ. However, since the wireless communication terminal 50 with the larger count value of its own counter has experienced more switching between group formation state and group integration state on the network, it can be assumed that this is a more accurate value (in other words, the wireless communication terminal with the smaller count value is more likely to be a deviating terminal), and the smaller count value is made to align with the larger count value.

[0081] Next, FIGS. 13A and 13B are flowcharts in which the necessary procedures relating to the matching restoration function of the deviated terminal are incorporated into the basic procedures (FIG. 11) of the wireless communication terminal 50 according to the second embodiment as described above. When comparing Figures 13A and 13B with the flowcharts of Figures 12A and 12B, the differences between the operation of the wireless communication terminal of embodiment 2 (Figure 11) and the operation of the wireless communication terminal of embodiment 1 (Figure 6A) are reflected as they are, but with regard to the required procedures related to the matching restoration function of the deviated terminal, the relevant procedure parts in Figures 13A and 12A and Figures 13B and 12B are exactly the same.

[0082] That is, steps S58-1, S58-2 and steps S74-1 to S76 in FIG. 13A correspond to steps S9-1, S9-2 and steps S24-1 to S26 in FIG. 12A, respectively, and steps S63-1, S63-2 and steps S81-1 to S81-5 in FIG. 13B correspond to steps S15-1, S15-2 and steps S31-1 to S31-5 in FIG. 12B, respectively. The operation procedure of FIG. 12C is also applied as it is to the communication using the group channel chX in step S52 of FIG. 13A and the communication using the common channel chZ in step S61 of FIG. 13B.

[0083] The function of restoring the alignment of the deviated terminal in the third embodiment is additionally incorporated into the control functions relating to the formation / integration of groups in the first and second embodiments. Therefore, the explanation of the basic operating procedures in Figures 13A and 13B will be left to the explanation in embodiment 2, and the explanation of the operating procedures related to the alignment restoration function of the deviated terminal will be left to the explanation in Figures 12A and 12B in embodiment 3. [Industrial Applicability]

[0084] The present invention can be applied to a network system that switches between a group formation state and a group integration state in a network of business-use wireless communication terminals and the like, and to a wireless communication terminal that realizes this. [Explanation of symbols]

[0085] 20...antenna, 21...distributor, 22...amplifier, RX...receiving and demodulating unit, 23...amplifier, 24...speaker, 25...microphone, 26...amplifier, TX...modulating and transmitting unit, 27...amplifier, 28...system control unit, 29...operating unit, 30...liquid crystal display unit, 31...buzzer, 50a, 50b, 50c...wireless communication terminal, 101-103, 201-203...wireless communication terminal.

Claims

1. A wireless communication network capable of assuming a group formation state in which there are N groups (where N is an integer of 2 or more) in which a plurality of wireless communication terminals communicate in a simplex manner using one channel (hereinafter referred to as "group channel"), each group having different channels, and a group integration state in which all wireless communication terminals belonging to the N groups communicate in a simplex manner using a common channel, the wireless communication terminal comprises a channel control means for setting a modulation / transmission unit and a reception / demodulation unit to the group channel of the group to which the terminal belongs (hereinafter referred to as "own group channel") during communication operation in the group formation state, and for setting the reception / demodulation unit to a scanning mode in which the reception / demodulation unit cyclically scans the own group channel, each group channel of the other (N-1) groups, and the common channel at a predetermined period during standby operation, and for setting the modulation / transmission unit and the reception / demodulation unit to the common channel in the group integration state; a state detection means for detecting, in the scanning mode of the reception / demodulation unit, a state in which no received signal is present on any scanned channel (hereinafter referred to as "first state"), a state in which a received signal is present on the own group channel and / or a group channel of the other (N-1) groups (hereinafter referred to as "second state"), or a state in which a received signal is present on the common channel (hereinafter referred to as "third state"); and an instruction means for instructing mutual switching between the group formation state and the group integration state, In the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting the first state, the set channel of the modulation / transmission unit and the reception / demodulation unit is switched from the own group channel to the common channel and a group unified signal is generated and transmitted, if the state detection means is detecting the second state, the reception / demodulation unit is switched from the scanning mode to a set state of the own group channel, and if the group unified signal transmitted by another wireless communication terminal is detected from a received signal on the common channel while the state detection means is detecting the third state, the set channel of the modulation / transmission unit and the reception / demodulation unit is switched from the own group channel to the common channel, In the group integration state, when a switching instruction is received from the instruction means, a group organization signal is generated and transmitted, and when the reception / demodulation unit receives the group organization signal transmitted by another wireless communication terminal, the set channels of the modulation / transmission unit and the reception / demodulation unit are immediately switched from the common channel to the channel of the group to which the terminal belongs, A wireless communication network system, characterized in that switching between the group formation state and the group integration state of the network is performed.

2. The wireless communication network system of claim 1, wherein the cyclic scanning in the scanning mode by the channel control means is performed at a predetermined interval in which the scanning time of the group channel belonging to the group is set to be sufficiently longer than the scanning time of each group channel of the other (N-1) groups and the scanning time of the common channel.

3. 2. The wireless communication network system according to claim 1, wherein when the state detection means detects the second state and there is a received signal on the group channel belonging to the group, the receiving and demodulating unit is switched from the scanning mode to the setting state of the group channel belonging to the group, but when there is a received signal only on group channels of other groups other than the group channel belonging to the group, the scanning mode of the receiving and demodulating unit is maintained and the state detection means returns to detecting the first state to the third state.

4. the wireless communication terminal is provided with a display means, 2. The wireless communication network system according to claim 1, wherein in the group formation state, a display is made indicating that switching to the group integration state is possible while the state detection means is detecting the first state, and in the group integration state, a display is made indicating that switching to the group formation state is possible during a period in which the modulation / transmission unit and the reception / demodulation unit are set to the common channel.

5. the wireless communication terminal is provided with a beep sound generating means, 2. The wireless communication network system according to claim 1, wherein, in the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting the first state, the beep generation means generates and transmits the group integration signal and then outputs a first beep, whereas, if a switching instruction is received from the instruction means while the state detection means is detecting a state other than the first state, the beep generation means immediately outputs a second beep; and, in the group formation state, if a switching instruction is received from the instruction means, the first beep or a third beep is output after generating and transmitting the group formation signal, and the first to third beeps are mutually different sounds.

6. the wireless communication terminal includes a counter; When transmitting the group integration signal or the group formation signal, the count value of the counter of the device itself is incremented by a predetermined number, and the incremented count value is added to the signal and transmitted; when receiving the group integration signal or the group formation signal, the count value (C1) added to the received group integration signal or the group formation signal is extracted and compared with the incremented count value (M) of the counter of the device itself; When the count value (C1) is greater than the count value (M), the modulation transmission unit and the reception / demodulation unit are set to the common channel or the own group channel according to the received signal, and the count value (M) is rewritten to the count value (C1), while when the count value (C1) is less than or equal to the count value (M), the set channels of the modulation transmission unit and the reception / demodulation unit are maintained as they are; When transmitting a communication signal related to a call, the count value of the counter of the device is always added to the communication frame and transmitted, while when receiving a communication frame from another wireless communication terminal, the count value (C2) added to the communication frame is extracted and compared with the count value (M) of the counter of the device; If the count value (C2) is greater than the count value (M), the count value (M) of the counter is rewritten to the count value (C2), whereas if the count value (C2) is less than or equal to the count value (M), the count value (M) of the counter is maintained as is.

6. A wireless communication network system according to claim 1, 2, 3, 4 or 5.

7. A wireless communication terminal applied to a wireless communication network capable of assuming a group formation state in which there are N groups (where N is an integer of 2 or more) in which a plurality of wireless communication terminals communicate in a simplex manner using one channel (hereinafter referred to as "group channel"), with the N groups having different channels, and a group integration state in which all wireless communication terminals belonging to the N groups communicate in a simplex manner using a common channel, and a channel control means for setting the modulation-transmission unit and the reception-demodulation unit to the group channel of the group to which the mobile station belongs (hereinafter referred to as "own group channel") during communication operation in the group formation state, and for setting the reception-demodulation unit to a scanning mode in which the reception-demodulation unit cyclically scans the own group channel, each group channel of the other (N-1) groups, and the common channel at a predetermined period during standby operation, and for setting the modulation-transmission unit and the reception-demodulation unit to the common channel in the group integration state; a state detection means for detecting whether the scanning mode of the reception-demodulation unit is in a state where no received signal is present on any scanned channel (hereinafter referred to as "first state"), a state where a received signal is present on the own group channel and / or a group channel of the other (N-1) groups (hereinafter referred to as "second state"), or a state where a received signal is present on the common channel (hereinafter referred to as "third state"); and an instruction means for instructing mutual switching between the group formation state and the group integration state, In the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting the first state, the set channel of the modulation / transmission unit and the reception / demodulation unit is switched from the own group channel to the common channel and a group unified signal is generated and transmitted, if the state detection means is detecting the second state, the reception / demodulation unit is switched from the scanning mode to a set state of the own group channel, and if the group unified signal transmitted by another wireless communication terminal is detected from a received signal on the common channel while the state detection means is detecting the third state, the set channel of the modulation / transmission unit and the reception / demodulation unit is switched from the own group channel to the common channel, In the group integration state, when a switching instruction is received from the instruction means, after generating and transmitting a group organization signal, and when the reception / demodulation unit receives the group organization signal transmitted by another wireless communication terminal, the set channels of the modulation / transmission unit and the reception / demodulation unit are immediately switched from the common channel to the channel of the group to which the terminal belongs. A wireless communication terminal characterized by:

8. The wireless communication terminal of claim 7, wherein the cyclic scanning in the scanning mode by the channel control means is performed at a predetermined interval in which the scanning time of the group channel belonging to the own group is set to be sufficiently longer than the scanning time of each group channel of the other (N-1) groups and the scanning time of the common channel.

9. 2. The wireless communication terminal according to claim 1, wherein when the state detection means detects the second state and there is a received signal on the group channel belonging to the group, the receiving and demodulating unit is switched from the scanning mode to a setting state for the group channel belonging to the group, but when there is a received signal only on a group channel of a group other than the group channel belonging to the group, the receiving and demodulating unit is maintained in the scanning mode and the state detection means returns to detecting the first state to the third state.

10. A display means is provided, 8. The wireless communication terminal according to claim 7, wherein in the group formation state, a display is made indicating that switching to the group integration state is possible while the state detection means is detecting the first state, and in the group integration state, a display is made indicating that switching to the group formation state is possible during a period in which the modulation / transmission unit and the reception / demodulation unit are set to the common channel.

11. beep sound generating means; 8. The wireless communication terminal according to claim 7, wherein, in the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting the first state, the beep generation means outputs a first beep after generating and transmitting the group integration signal, while, in the group formation state, if a switching instruction is received from the instruction means while the state detection means is detecting a state other than the first state, the beep generation means immediately outputs a second beep, and, in the group formation state, if a switching instruction is received from the instruction means, the wireless communication terminal generates and transmits the group formation signal and then outputs the first beep or a third beep, and the first to third beeps are mutually different sounds.

12. Equipped with a counter, When transmitting the group integration signal or the group formation signal, the count value of the counter of the device itself is incremented by a predetermined number, and the incremented count value is added to the signal and transmitted; when receiving the group integration signal or the group formation signal, the count value (C1) added to the received group integration signal or the group formation signal is extracted and compared with the incremented count value (M) of the counter of the device itself; When the count value (C1) is greater than the count value (M), the modulation transmission unit and the reception / demodulation unit are set to the common channel or the own group channel according to the received signal, and the count value (M) is rewritten to the count value (C1), while when the count value (C1) is less than or equal to the count value (M), the set channels of the modulation transmission unit and the reception / demodulation unit are maintained as they are; When transmitting a communication signal related to a call, the count value of the counter of the device is always added to the communication frame and transmitted, while when receiving a communication frame from another wireless communication terminal, the count value (C2) added to the communication frame is extracted and compared with the count value (M) of the counter of the device; If the count value (C2) is greater than the count value (M), the count value (M) of the counter is rewritten to the count value (C2), whereas if the count value (C2) is less than or equal to the count value (M), the count value (M) of the counter is maintained as is.

12. The wireless communication terminal according to claim 7, 8, 9, 10 or 11.

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