JP6544081B2 - Wireless communication system, wireless communication apparatus, control method for wireless communication apparatus, and control program for wireless communication apparatus - Google Patents

Description

  The present invention relates to a wireless communication system, a wireless communication apparatus, a control method for a wireless communication apparatus, and a control program for a wireless communication apparatus, and more particularly to control of communication of a plurality of wireless terminals in the same frequency band.

  When a number of wireless terminals communicate in the same frequency band (channel), if multiple terminals transmit wireless signals at the same timing, these wireless signals will interfere at the receiving terminal and communication will be interrupted There is. On the other hand, communication that avoids interference of radio signals can be realized by time division multiple access (TDMA). For example, a specific terminal (management terminal) assigns a time slot (time slot) for transmitting a signal to each other terminal to other terminals, thereby causing collisions of radio signals to a large number of terminals and using the same channel. There is a method of communicating. This system is called centralized management TDMA communication system.

  In such a scheme, when joining a network, a terminal other than the management terminal transmits a signal inquiring the management terminal of the time slot of its own terminal. The management terminal realizes time slot allocation by notifying the inquiring source terminal of the time slot in response to the signal.

  Also, when the management terminal detects that a terminal to which a time slot has been allocated has left the network, the management terminal can delete the allocation of the time slot and make that slot available for allocation to another terminal. By doing this, it becomes possible to allocate a time slot in accordance with the presence or absence of the terminal even in a situation where participation or withdrawal to the network occurs due to movement of the terminal or the like.

  According to Patent Document 1, when there is a call disconnection during a call of a mobile radio terminal, the time slot used by the terminal is kept for a predetermined time, and the terminal returns within the predetermined time. It has been proposed to use the time slot continuously. As a result, in Patent Document 1, it is possible to reliably reassign a time slot to a terminal where a call disconnection has occurred within a predetermined time.

JP-A-7-30943

  However, the above-described time slot allocation scheme has the following problems.

  A case will be considered where the wireless terminal performing communication by TDMA tries to return to the network after leaving the network once due to reasons such as movement. The first problem is that a control signal is generated each time such a wireless terminal leaves the network and then tries to return to the network. The reason is that when returning to the network, even if the previously used time slot is available, it is necessary to rejoin the network.

  It demonstrates using the example shown to Fig.1 (a)-FIG.1 (c). FIG. 1 (a) is a schematic view showing an initial state of time slot allocation, FIG. 1 (b) is a schematic view showing a state of leaving the network due to movement of the terminal, and FIG. 1 (c) is a terminal It is a general view which shows the state which re-appeared and returned to the original position. In the initial state (FIG. 1A), the terminal A is a management terminal, and time slots are already allocated to the terminals A to E.

  When the terminals E and D move from here and leave the network (FIG. 1 (b)), the terminal A (management terminal) that detects the leaving of the terminal erases the time slot assignments of the disconnected terminals E and D, Make time slots available for assignment to other terminals. After that, when the terminals E and D approach each other again as shown in FIG. 1 (c), the assignment of time slots is not changed. For this reason, even if the time slot originally used by the terminals E and D remains an empty slot, the terminals E and D must not perform the process of joining the network (processing of assigning the time slot to the management terminal). You must.

  As described above, in the centralized management type TDMA communication system of the background art, once the terminal leaves the network, it is necessary to always perform the joining process again when returning after that, and a control signal is generated each time. In Patent Document 1, there is disclosed a technique of storing a time slot used by a terminal from which a management terminal has left, and allocating the time slot to a terminal which has been restored when returning within a predetermined time. However, this technique can not reduce the control signal when rejoining. That is, the problem to be solved by the present invention is not solved.

  The second problem is that it takes time for the restored terminal to be able to communicate again in the process in which a large number of terminals that have left the network once join the original network again. Even if the previously used time slot is not allocated to another terminal, processing for inquiring the time slot to the management terminal has to be performed again, and communication can be performed until it is completed. It was not.

  Particularly in a multi-hop environment, the problem of taking time to be able to communicate again becomes significant. It demonstrates using the example shown to FIG. 2 (a)-FIG.2 (c). FIG. 2 (a) is a schematic diagram showing an initial state of time slot allocation in a multi-hop environment, and FIG. 2 (b) is a schematic diagram showing a detached state from the network due to movement of a terminal. c) is a schematic view showing a state in which the terminal approaches again and returns to the original position. In the initial state (FIG. 2A), the terminal A is a management terminal, and time slots are assigned to the terminals A to F to configure a multi-hop network. From here, consider the case where the terminals D, E, F leave (FIG. 2 (b)) and then approach again and return to the original position (FIG. 2 (c)). At this time, first, the terminal E close to the network performs a joining process, and after the joining process is completed, the joining process of the terminals D and F is performed via the terminal E. That is, when a plurality of terminals return to the network, subscription processing is sequentially performed from terminals in a short distance that can directly communicate with the terminals in the network, so that each of the plurality of terminals can communicate in a multi-hop environment Takes time.

[Object of the invention]
The object of the present invention is to provide a wireless communication system, a wireless communication device, a control method of a wireless communication device, and a wireless communication device capable of reducing control signals when the terminal returns to the network after a certain terminal leaves the network. Providing a control program of a communication device.

  Another object of the present invention is a wireless communication system, which enables communication with a terminal in the network again in a short time when the terminal returns to the network when the terminal once leaves the network. A communication device, a control method of a wireless communication device, and a control program of the wireless communication device.

In order to achieve the above object, a wireless communication system according to the present invention has a management terminal having a function of assigning communication resources to each terminal constituting the wireless communication system, and other terminals to which the communication resources are assigned.
The above management terminal is
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed;
A means for determining whether the terminal to which the own terminal has allocated communication resources in the past can communicate with the own terminal;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
And means for considering that communication resources are allocated to the terminal when communication is possible.

A wireless communication apparatus according to the present invention has a function of assigning communication resources to each terminal constituting a wireless communication system,
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed;
A means for determining whether communication with a terminal constituting the wireless communication system, which has been allocated communication resources in the past, is possible;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
And means for considering that communication resources are allocated to the terminal when communication is possible.

A control method of a wireless communication apparatus according to the present invention is a control method of a wireless communication apparatus for allocating communication resources to each terminal constituting a wireless communication system,
Transmitting a signal including an identifier indicating that the allocation of the communication resource has changed;
It is determined whether communication is possible with a terminal constituting the above-mentioned wireless communication system which has allocated communication resources in the past, as a destination.
As a result of the determination, if communication is possible, it is considered that the communication resource is not allocated to the terminal, and if communication is not possible, it is considered that the communication resource is not allocated to the terminal.

A control program of a wireless communication apparatus according to the present invention is a control program of a wireless communication apparatus for assigning communication resources to each terminal constituting a wireless communication system, and a computer,
A process of transmitting a signal including an identifier indicating that the allocation of the communication resource has changed;
A process of determining whether communication is possible with the terminal constituting the wireless communication system which has allocated communication resources in the past, and as a result of the determination, if communication is possible, the communication resource is transmitted to the terminal Is considered to be unassigned, and if communication is not possible, the terminal is processed to consider that no communication resource is assigned.

  According to the present invention, when a certain terminal leaves the network once, it is possible to reduce control signals when the terminal returns to the network.

(A) is an overview diagram showing an initial state of time slot allocation in a multi-hop environment, (b) is an overview diagram showing a state of leaving the network due to movement of the terminal, (c) is an overview It is a general view which shows the state which approached and returned to the original position. (A) is an overview diagram showing an initial state of time slot allocation in a multi-hop environment, (b) is an overview diagram showing a state of leaving the network due to movement of the terminal, (c) is an overview It is a general view which shows the state which approached and returned to the original position. It is a figure which shows the network which the radio | wireless communications system of the 1st Embodiment of this invention makes object. It is a block diagram which shows the structure of the management terminal of the 1st Embodiment of this invention, and the general terminal which communicates with this management terminal. It is a block diagram which shows the structure of the general terminal of the 1st Embodiment of this invention, and the management terminal and other general terminals which communicate with this general terminal. It is a figure which shows the flow of the process which the management terminal of the 1st Embodiment of this invention allocates a slot. It is a figure which shows the flow of the process which the management terminal of the 1st Embodiment of this invention erase | eliminates or resets slot allocation. It is a figure which shows the flow of the process which the management terminal of the 1st Embodiment of this invention transmits a beacon. It is a figure which shows the flow of the process for the general terminal of 1st Embodiment of this invention to join a network. It is a figure which shows the flow of the process which the general terminal of the 1st Embodiment of this invention transfers a beacon. It is a figure which shows the flow of the process in which the general terminal of the 1st Embodiment of this invention judges a connection state. It is a figure which shows the example of how to determine the set of time slots. FIG. 13 is a diagram showing a flow of processing in which a management terminal allocates slots in the second embodiment of the present invention. FIG. 10 is a diagram showing a flow of processing in which a management terminal transmits a beacon in the second embodiment of the present invention. FIG. 7 is a diagram showing the flow of processing for a general terminal to join a network in the second embodiment of the present invention. It is a block diagram which shows the structure of the management terminal of other embodiment of this invention, and the general terminal which communicates with this management terminal. It is a block diagram which shows the structure of the general terminal of other embodiment of this invention, and the management terminal and other general terminal which communicate with this general terminal.

  Preferred embodiments of the present invention will be described in detail with reference to the drawings.

First Embodiment
First, a wireless communication system according to a first embodiment of the present invention will be described.

[Description of configuration]
First, a target network in the present embodiment will be described. The present embodiment is directed to a network N1 shown in FIG. 3 in which a plurality of wireless terminals A1 and A′1 communicate with each other in a time division manner.

  As shown in FIG. 3, a single management terminal A1 and a plurality of other terminals (general terminals) A'1 exist in the network N1. Among the plurality of wireless terminals of the network N1, one wireless terminal is the management terminal A1. Each of these terminals can communicate with each other, and may be connected by a single hop, or may be connected by a multihop. Each terminal is assigned a time slot which is a period during which each terminal can transmit a radio signal, and each terminal holds the number of the time slot to which its own terminal is assigned. Further, it is assumed that the management terminal holds information on time slot allocation (a set of terminal identifier and time slot number) of all terminals including the own terminal. Furthermore, each terminal is assumed to be synchronized in time in order to realize communication in time division. This time synchronization can be realized by using signals from satellites such as GPS (Global Positioning System) or by sharing signals for synchronization emitted by specific terminals between terminals.

  In the present embodiment, a time slot refers to a time zone (frame) repeated at a cycle of a predetermined length, divided by the time of the predetermined length and divided. May be defined in different ways. That is, the time slot does not have to be repeated in a determined cycle, and may be a period starting from a predetermined time, or a period determined based on a signal transmitted by a specific terminal such as a management terminal. It is also good. Further, in the present embodiment, it is assumed that numbers which do not overlap with time slots are assigned in advance.

  Each terminal A1 and A'1 in the network periodically transmits a beacon including an identifier of the management terminal A1. The general terminal A'1 not holding the slot assignment detects the presence of the network by receiving this beacon. Thereafter, a slot request signal is transmitted to the management terminal included in the beacon, and the slot allocation is acquired by receiving the slot allocation signal as a reply to the signal. Although details will be described later, a process of joining a network and a process of determining whether to continue to use a time slot are performed using the information included in the beacon.

  It is assumed that each terminal in the network operates a routing control protocol for setting a path to another terminal proactively, such as an Optimized Link State Routing (OLSR) protocol. The routing control information is used in the process of investigating the terminals existing in the network, which will be described in detail later. However, the routing control protocol may be different depending on the variation of the method of checking the terminals present in the network.

  The configuration of the management terminal A1 will be described. The configuration of the management terminal is shown in FIG. The management terminal A1 includes a wireless communication unit A10, a slot management unit A11, a disconnection / return detection unit A12 for a general terminal, a slot change information notification unit A13, a slot assignment storage unit A14, and a slot change information storage unit A15.

  The wireless communication unit A10 transmits and receives wireless signals. Specifically, the wireless communication unit A10 transmits signals notified from the slot management unit A11, the disconnection / return detection unit A12 for the general terminal, and the slot change information notification unit A13. At this time, transmission of the radio signal is performed at timing based on the time slot number assigned to the own terminal stored in the slot assignment storage unit A14. Also, the wireless communication unit A10 notifies the slot management unit A11 of the received slot request signal.

  In addition, while the wireless communication unit A10 exchanges control information with the wireless communication unit A'10 of the other general terminal A'1 according to a predetermined routing control protocol, a route between any slot-assigned terminal Make settings for The route table set here is used when an application of the upper layer communicates, and is also used in processing for investigating terminals existing in the network in the general terminal removal / return detection unit A12 which will be described in detail later.

  The slot management unit A11 manages time slot allocation. The slot management unit A11 performs a process of determining the assignment of a time slot to an arbitrary terminal and a process of erasing the assignment, and a process of notifying the terminal of the result, a slot assignment storage unit A14, and a slot change information storage unit Perform processing to save in A15.

  The management of time slot allocation consists of three patterns of slot allocation for participation processing of general terminal A'1, elimination of the time slot of the separated general terminal, and resetting of the time slot of the recovered general terminal.

  First, the case where slot allocation for the participation process of the general terminal A′1 is performed will be described. When the slot management unit A11 receives a slot request signal from the wireless communication unit A10, the slot management unit A11 refers to the slot allocation storage unit A14. Then, the slot management unit A11 selects one time slot (empty slot) not stored in the slot assignment storage unit A14, and transmits a slot assignment signal including the number via the wireless communication unit A10.

  In the present embodiment, the selection of the time slot to be assigned is the one with the smallest number among the empty slots, but it is not limited to this. That is, time slots to be assigned may be selected at random, or may be selected based on an identifier of a terminal that performs participation processing or information included in a participation request signal. A slot other than the slot used previously by any terminal stored in the slot change information storage unit A15 described later may be preferentially selected.

  Also, the slot management unit A11 stores the set of the selected time slot number and the general terminal to which the time slot is assigned in the slot assignment storage unit A14 as slot assignment information. Thereafter, the slot management unit A11 refers to the slot assignment erased information held by the slot change information storage unit A15. Note that the slot allocation erased information is information that the slot management unit A11 stores when erasing a time slot of a detached general terminal described later. When the slot allocation erased information includes the selected time slot, the slot management unit A11 deletes the slot allocation erased information. Then, the slot management unit A11 stores slot overwrite timing information in the slot change information storage unit A15 as information indicating the timing when the slot is overwritten.

  In this embodiment, the time is stored as slot overwrite timing information, but the present invention is not limited to this. The slot overwrite timing information to be stored may be a sequence number or a sequence in which randomly generated values do not overlap may be used.

  The elimination of the time slot of the detached general terminal will be described. The slot management unit A11 deletes the slot allocation information of the identifier existing in the slot allocation storage unit when receiving notification of the disconnection of the general terminal and its identifier from the disconnection / return detection unit A12 of the general terminal. In addition, the slot allocation information (the pair of the identifier and the slot number or the set thereof) deleted at this time is stored as slot allocation erased information in the slot change information storage unit A15.

  The resetting of the time slot of the restored general terminal will be described. The slot management unit A11 is notified of the return of the general terminal and its identifier from the disconnection / return detection unit A12 of the general terminal, and when the slot change storage unit stores the slot assignment erased information of the identifier, Delete slot assignment erased information. A set of a time slot number and an identifier assigned in the past, which is included in the deleted slot assignment erased information, is stored in the slot assignment storage unit A14 as slot assignment information of the terminal.

  The disconnection / return detection unit A12 of the general terminal detects that the general terminal has left the network or returned to the network, and notifies the slot management unit A11. The departure / return detection unit A12 of the general terminal first checks the terminals existing in the network, and compares the information with the information stored in the slot allocation storage unit A14 and the slot change information storage unit A15 to obtain the general terminal. To detect the departure and return of Note that the presence of a general terminal in the network means that the terminal can transmit and receive signals with the management terminal. The transmission and reception of this signal may be single hop or multihop.

  Details of the processing of the disconnection / return detection unit A12 of the general terminal will be described. In the present embodiment, the investigation of the terminals present in the network is determined using the route table obtained by the process of the wireless communication unit A10. In the present embodiment, it is assumed that a route control protocol for setting a route proactively, so the identifier of the terminal present in the network is present in the route table. Therefore, in the present embodiment, a terminal whose identifier exists in the route table obtained by the processing of the wireless communication unit A10 exists in the network, and a terminal whose identifier does not exist in the route table exists in the network I will judge that I do not do it. In this embodiment, this processing is performed at a predetermined cycle, but this may be performed at timing determined by another method. For example, it may be triggered by the wireless communication unit A10 receiving or transmitting the path control information.

  It should be noted that another method may be used to investigate the terminals present in the network. If all the terminals can directly communicate with the management terminal, the wireless communication unit A10 of the management terminal may intercept the signal of the terminal transmitting the signal and check the terminals existing in the network. In addition, when all the terminals can directly communicate with the management terminal, a signal indicating the presence of the own terminal is periodically transmitted to the management terminal to check each terminal existing in the network. It is also good. In addition, if there is a function that recognizes a terminal in the network by the function of another application, that information may be used.

  In the case where the investigation of the terminals present in the network is realized without using the routing control information, it is not assumed that the proactive routing control protocol as described in the description of the target network in this embodiment is used. It is also good.

  The departure / return detection unit A12 of the general terminal checks terminals existing in the network, and then compares the information with the information stored in the slot allocation storage unit A14. If the terminal identifier included in the slot allocation information stored in the slot allocation storage unit A14 is not included in the terminal existing in the network, it is determined that the general terminal has left, and the slot management unit together with the identifier of the terminal Notify A11.

  Conversely, when the identifier of the terminal present in the network is not included in the slot assignment information stored in the slot assignment storage unit A14, the following is performed. If the identifier is included in the slot assignment erased information stored in the slot change information storage unit A15, it is determined that the general terminal is restored, and is notified to the slot management unit A11 together with the identifier of the terminal.

  The slot change information notification unit A13 generates a beacon based on the slot change slot overwrite timing information included in the slot change information storage unit A15, and transmits the beacon via the wireless communication unit A10.

  Specifically, among the slot overwrite timing information stored in the slot change information storage unit A15, the one indicating the latest timing is extracted at a predetermined cycle, and a beacon including the information is generated. The generated beacon is transmitted via the wireless communication unit A10.

  When slot overwrite timing information does not exist in the slot change information storage unit A15, a beacon including information indicating that the slot overwrite timing information does not exist is generated and transmitted via the wireless communication unit A10. This beacon is the same as the beacon transmitted by each terminal described in the description of the network targeted by the present embodiment described above. If slot overwrite timing information is present, the beacon at least includes the latest slot overwrite timing information and information on the identifier of the management terminal. If slot overwrite timing information does not exist, the beacon includes at least information on the identifier of the management terminal.

  In the present embodiment, the time format information stored in the slot change information storage unit A15 is included as it is in the beacon, but may be processed into a different format. That is, it may be converted into information indicating that the slot has not been changed for a certain time in the past, and the information may be included.

  However, in order to realize different applications and functions of network protocols, if any beacon is transmitted, the beacon may include slot overwrite timing information.

  By referring to the beacon generated by the slot change information notification unit A13, the general terminal A′1 having left the network can know whether the slot allocation has been changed since the terminal has left the network. The details will be described in the description of the configuration of the general terminal A'1.

  The slot assignment storage unit A14 stores slot assignment information (a set of a terminal identifier and an assigned terminal) notified from the slot management unit A11. This information is referred to in the wireless communication unit A10, the slot management unit A11, and the disconnection / return detection unit A12 of the general terminal. In the present embodiment, it is assumed that slot allocation information for a terminal to which a time slot has been allocated in the initial state is held as an initial value.

  The slot change information storage unit A15 stores slot assignment erased information notified from the slot management unit A11 and slot overwrite timing information. These pieces of information are referred to by the slot management unit A11, the disconnection / return detection unit A12 of the general terminal, and the slot change information notification unit A13.

  Next, the configuration of the general terminal A'1 will be described. The configuration of the general terminal is shown in FIG. The general terminal A′1 includes a wireless communication unit A′10, a subscription processing unit A′11, a connection state determination unit A′12, a continuous use determination unit A′13, and a slot information storage unit A′14.

  The wireless communication unit A'10 transmits and receives wireless signals. A beacon received by a management terminal or a general terminal other than the terminal itself is received, and processing is performed to notify the subscription processing unit A'11, the connection state determination unit A'12, and the continuous use determination unit A'13. Also, processing of transmitting and receiving control signals exchanged for network joining processing between the subscription processing unit A ′ 11 and the management terminal A 1 and processing of transferring signals of other terminals are performed. Moreover, when a beacon is received from a management terminal or another general terminal, the beacon is transferred. In addition, the wireless communication unit A'10 performs route setting while exchanging control information with the wireless communication units A10 and A'10 of the other terminals in accordance with a predetermined route control protocol, and at least the management terminal A1 and the other terminals. Establish a route to any terminal.

  The transmission of the radio signal in these processes is performed at the timing based on the time slot information stored in the slot information storage unit A'14 except when transmitting the control signal notified from the subscription processing unit A'11. It will be. However, when the invalidation flag is added to the time slot information by the connection state determination unit A ′ 12 described later, transmission of signals other than the slot request signal is not performed as in the case where the time slot information is not provided.

  The subscription processing unit A'11 performs subscription processing to the network, and stores slot information allocated to the slot information storage unit A'14. When the slot allocation information is not stored in the slot information storage unit A′14, the subscription processing unit A′11 is notified of the beacon received from the wireless communication unit A′10, the management terminal included in the beacon A slot request signal is transmitted to the management terminal based on the identifier. In this embodiment, this slot request signal is transmitted in a randomly selected time slot.

  Thereafter, when the slot assignment signal transmitted from the management terminal is received through the wireless communication unit A'10, the slot number of the time slot included in the slot assignment signal is stored in the slot information storage unit A'14 as time slot information. .

  When time slot information is stored in the slot information storage unit A'14 and an invalidation flag is added by the connection state determination unit A'12 described later, the continuation use determination unit A'13 described below continues Only when it is notified that the service is unavailable, the network subscription process is performed. That is, when time slot information is stored in the slot information storage unit A ′ 14 and a beacon is received with the invalid flag added, the continuous use determining unit A ′ 13 determines whether continuous use is possible. As a result of this determination, when the subscription processing unit A ′ 11 is notified that the continuous use is not possible, the subscription processing unit A ′ 11 performs a process of joining the network.

  Also in this case, the slot request signal is transmitted to the management terminal in the same manner as the method described above, and the time slot number included in the slot assignment signal received from the management terminal is stored as time slot information in the information storage unit. At this time, the allocated time slot information to which the invalid flag is added, which is stored in the slot information storage unit A'14, is deleted.

  If the allocated time slot is stored in the slot information storage unit A ′ 14 and the invalidation flag is not added by the connection state determination unit A ′ 12 described later, the joining process to the network is not performed.

  The connection state determination unit A ′ 12 determines whether the own terminal exists in the network (can communicate with the management terminal). Specifically, the timeout time is determined in advance, and it is determined that the own terminal does not exist in the network when the elapsed time since the reception of the beacon by the wireless communication unit A'10 finally exceeds the timeout time. Do. In that case, the connection state determination unit A ′ 12 adds an invalidation flag to the allocation time slot information included in the slot information storage unit A ′ 14 and records the time as the network departure time. However, when the invalidation flag is already added to the time slot information, the connection state determination unit A'12 does not perform any processing.

  In this embodiment, since it is determined whether the slot allocation has been overwritten after the own terminal has left based on the time, the connection state determination unit A ′ 12 records the network leaving time. However, different values can be recorded in accordance with the information contained in the beacon generated by the slot change information notification unit A13 of the management terminal A1. For example, as described above, the slot management unit A11 of the management terminal A1 may store, as slot overwrite timing information, information of a sequence number or a randomly generated sequence instead of time in the slot change information storage unit A15. In that case, since the slot change information notification unit A13 generates a beacon based on the information, the connection state determination unit A'12 stores the slot overwrite timing information included in the beacon received last, instead of the time. .

  When the own terminal does not exist in the network and receives a beacon, the continuous use determining unit A '13 determines whether to continue to use the time slot used in the past. In other words, when the own terminal can not communicate with the management terminal and receives a beacon, the continuous use determining unit A ′ 13 determines whether to continue to use the time slot used in the past. When the continuous use is possible, the invalidation flag of the slot information storage unit A'14 is deleted. If the continuous use is not possible, the subscription processing unit A'11 is notified that the continuous use is not possible.

  The details of the continuous use determination unit A '13 will be described. The continuous use determination unit A'13 performs processing only when reception of a beacon is notified from the wireless communication unit A'10 in a state where an invalid flag is added to the allocated slot information of the slot information storage unit A'14. . At this time, the slot overwrite timing information included in the received beacon is compared with the network departure time included in the slot information storage unit A′14, and when the slot overwrite timing information is older, it is determined that the continuous use is possible. If the slot overwrite timing information is newer, it is determined that the continuous use is not possible. If it is determined that the continuous use is possible, the invalid flag and the network departure time added to the allocated slot information included in the slot information storage unit A ′ 14 are deleted. When it is determined that the continuous use is not possible, the subscription processing unit A'11 is notified that the continuous use is not possible.

  In the present embodiment, whether the continuous use is possible is realized by a simple comparison of the slot overwrite timing information and the network leaving time, but this may be another method. For example, a predetermined time may be added to the network departure time to compare with slot overwrite timing information.

  Further, when using a sequence number or a randomly generated sequence as slot overwrite timing information, the following is performed. That is, by comparing the slot overwrite timing information stored in the slot information storage unit A ′ 14 with the slot overwrite timing information of the received beacon, the connection state determination unit A ′ 12 determines whether the continuous use is possible.

  In this case, when the information stored in the slot information storage unit A ′ 14 and the slot overwrite timing information of the beacon are different, it can be determined that the information can not be continuously used. When the sequence number is used as slot overwrite timing information, it may be determined whether the continuous use is possible by size comparison.

  In this way, when a terminal once leaving the network recovers, the own terminal has been using it in the past when the slot allocation has not been changed based on the information contained in the beacon emitted by the terminals in the network. Continue to use the new slot. Thereby, the slot assignment can be reused without generating a control signal.

[Description of operation]
Next, the operation of the first embodiment will be described with reference to FIGS. 6, 7, 8, 9, 10, and 11. FIG. A network as shown in FIG. 3 is configured, and a state in which a time slot is already assigned to each terminal is taken as an initial state, and from this state, operations of the management terminal A1 and the general terminal A′1 will be described.

  First, the operation of the management terminal A1 will be described. The management terminal A1 assigns a slot to the general terminal A'1 which is going to join the network, processes to delete or reset the slot assignment according to the withdrawal / return of the general terminal, and sends a beacon. Do. In the present embodiment, these three processes are performed at mutually independent timings.

  A flow of processing for assigning a slot to the general terminal A'1 which is going to join the network is shown in FIG. This process is performed triggered by the process (step S00) of receiving a signal in the wireless communication unit A′10. When the received signal is a slot request signal, the slot management unit A11 performs slot determination processing (step S01). In the slot determination process (step S01), the slot to be allocated to the terminal of the slot request signal transmission source is determined to generate slot allocation information D00, and the slot allocation information D00 is stored in the slot allocation storage unit A14. When the determined slot is stored in the slot change information storage unit A15 as the slot assignment erased information D11, the slot assignment erased information D11 is deleted. Along with this deletion, slot overwrite timing information D01 is generated and stored in slot change information storage unit A15.

  Thereafter, slot allocation signal transmission processing (step S02) is performed. In slot assignment signal transmission processing (step S02), a slot assignment signal is generated based on the slot assignment information D00, and transmitted to the terminal of the slot request signal transmission source through the wireless communication unit A10.

  FIG. 7 shows the flow of processing for deleting or resetting the slot assignment in accordance with the withdrawal / return of the general terminal. In the present embodiment, this process is performed at a predetermined cycle. However, the timing at which the process is performed may be determined by, for example, receiving the route control information.

  In this process, first, a path control process (step S10) and a disconnection / return detection process of the general terminal (step S11) are performed. In the present embodiment, these processes are performed in the order of the path control process (step S10) and the disconnection / return detection process (step S11) of the general terminal, but these processes may be performed at independent timings. . The route control process (step S10) is a process of setting a route to another terminal in the wireless communication unit A′10. Using the route table D10 created in this process, the general terminal removal / return detection processing (step S11) is performed by the general terminal removal / return detection unit A12. In the disconnection / return detection processing (step S11) of the general terminal, based on the routing table D10, the slot assignment information D00 held by the slot assignment storage unit A14, and the slot assignment erased information D11 held by the slot change information storage unit A15. , Detect the withdrawal and return of the general terminal.

  When departure of a general terminal is detected, the slot management unit A11 performs slot assignment deletion processing (step S12). In the slot assignment deletion process (step S12), deletion of the slot assignment information D00 in the slot assignment storage unit A14 and storage of the slot assignment erased information D11 in the slot change storage unit A15 are performed. The deletion of the slot assignment information D00 and the storage of the slot assignment erased information D11 are performed based on the identifier of the terminal notified from the detachment / return detection unit A12 of the general terminal.

  When return of the general terminal is detected, slot reassignment processing (step S13) is performed in the slot management unit A11. In the slot reassignment process (step S13), deletion of the slot assignment erased information D11 present in the slot change information storage unit A15 and storage of the slot assignment information D00 in the slot assignment storage unit A14 are performed. The deletion of the slot allocation erased information D11 and the storage of the slot allocation information D00 are performed based on the identifier of the terminal notified from the detachment / return detection unit A12 of the general terminal.

  A flow of beacon transmission processing is shown in FIG. In this embodiment, this process is performed at a predetermined cycle. In the beacon transmission process, the slot change information notification unit A13 first performs beacon generation process (step S20). In the beacon generation process (step S20), a beacon is generated based on the slot overwrite timing information D01. Thereafter, beacon transmission processing (step S21) is performed by the wireless communication unit A10, and the beacon is actually transmitted.

  Next, the operation of the general terminal A'1 will be described. The operation of the general terminal includes a process for joining a network, a process for transferring a beacon, and a process for determining a connection state.

  A flow of processing for joining a network is shown in FIG. In this process, first, the wireless communication unit A'10 performs beacon reception process (step S'00). As long as the beacon is not received, no process for joining the network is performed. Also, this process is not performed if the network has already been joined after receiving the beacon. It can be determined that there is time slot information to which the invalid flag is not added in the slot information storage unit A'14 that the network has already been joined.

  If not, then a determination is made as to whether the network was previously subscribed. This can be determined by the presence of time slot information in which the invalid flag is added to the slot information storage unit A'14. If the user has joined the network before, the continued use determining unit A'13 determines whether the slot can be used continuously (step S'04). This determination process is performed based on the network leaving time D'00 stored by the connection state determination unit A'12 and the slot overwrite timing information included in the received beacon.

  When it is determined that the network has not been joined before (when time slot information does not exist in the slot information storage unit A'14) and when it is determined that the continuous use is not possible, the slot processing unit A'11 processes slot request signal transmission processing. (Step S'01) is performed. In this process, a slot request signal is transmitted to the management terminal A1. Next, slot allocation signal reception processing (step S'02) is performed to wait for reception of the slot allocation signal. When the slot assignment signal is received, the subscription processing unit A'11 saves the time slot information D'01 in the slot information storage unit in the slot assignment storage process (step S'03).

  Further, if it is determined in the process of determining whether the continuous use is possible (step S'04), the continuous use determining unit A'13 performs the allocation slot information updating process (step S'05) if it is determined that the continuous use is possible. Do. In the allocation slot information updating process (step S'05), the continuous use determining unit A'13 deletes the invalid flag and the network departure time added to the time slot information held by the slot information storage unit A'14.

  A flow of processing for transferring a beacon is shown in FIG. After the reception process (step S'10) of the beacon is performed in the wireless communication unit A'10, the transfer process (step S'11) of the beacon is similarly performed in the wireless communication unit A'10. If all terminals in the network can communicate with the management terminal in a single hop communication network, the process of transferring the beacon shown in FIG. 10 is unnecessary.

  A flow of processing for determining the connection state is shown in FIG. This processing performs beacon monitoring processing (step S'20) in the wireless communication unit A'10 to monitor whether a beacon is received. When a beacon is received, a timer reset process (step S'21), which is a process of resetting a timer for timeout measurement in the connection state determination unit A'12, is performed. When the beacon is not received for a predetermined time or more, the connection state determination unit A'12 performs an invalid flag addition / time recording process (step S'22) due to the beacon timeout. In this process, an invalid flag is added to the time slot information stored in the slot information storage unit A'14, and the network departure time D'00 is stored in the slot information storage unit A'14.

  Also, the general terminal performs processing of path control independently of these processings. This is processing for creating a routing table with an arbitrary terminal on the management terminal in cooperation with the route control process (step S10) described in the operation of the management terminal in the wireless communication unit A′10.

[Description of effect]
Next, the effects of the present embodiment will be described. As in the present embodiment, the general terminal A'1 that has temporarily left the network by transmitting a beacon including the time when the slot was last overwritten, causes the own terminal to transmit in the past. It is possible to determine whether the slot being used can be continued. Therefore, it is possible to rejoin the network using the previously used slot again without transmitting the slot request signal. Also, since the management terminal A1 can check that the general terminal A'1 has returned to the network by utilizing the path control information, it is possible to return the general terminal A'1 without generating a control signal additionally. At the same time, the slot assignment information on the management terminal can be updated. In this manner, according to the present embodiment, the effect of reducing control signals when a terminal that has temporarily left the network returns to the network can be obtained.

  Also, in this embodiment, when a terminal that has temporarily left the network returns to the network, the terminal itself does not perform processing for waiting for transmission of a slot request signal to the management terminal or reception of a slot assignment signal. Communication can be performed using the assigned time slot. That is, when a terminal that has temporarily left the network returns to the network, it becomes unnecessary to transmit a slot request signal to the management terminal managing the time slot, and slot assignment from the management terminal managing the time slot becomes There is no need to wait to receive a signal.

  Therefore, according to the present embodiment, when a terminal that has been temporarily disconnected returns to the network, communication can be started in a short time. Even in the case where a plurality of terminals temporarily leave in a multi-hop environment as shown in FIG. 2, if a terminal close to the management terminal (for example, terminal E in FIG. 2) continues to use slots, It becomes possible to communicate. As a result, the time for the terminals (for example, terminals F and D in FIG. 2) far from the management terminal that has received the beacon transmitted by that terminal to start re-joining processing also becomes short. As a result, the time until a plurality of disconnected terminals can communicate again becomes short.

Second Embodiment
Next, a wireless communication system according to a second embodiment of the present invention will be described. In the first embodiment, the determination as to whether to continue to use the slot is made based on the information of the timing at which any time slot allocation is overwritten. On the other hand, in the second embodiment, the determination as to whether to continue using the slot is performed based not only on the information on the timing at which the time slot allocation is overwritten but also on the information on which time slot allocation is overwritten. . In addition, since many parts of the second embodiment operate in the same manner as the first embodiment, only the parts that are modified from the first embodiment will be described.

[Description of configuration]
The second embodiment is also directed to a network N1 in which a plurality of wireless terminals A1 and A′1 communicate with each other in a time division manner as shown in FIG. 3 as in the first embodiment. Further, the initial state is also the same as in the first embodiment, and a time slot is already assigned to each terminal.

  The configuration of the management terminal A1 in the second embodiment is shown in FIG. 4 as in the first embodiment. Among them, in the second embodiment, only the processing of the slot management unit A11, the slot change information notification unit A13, and the slot change information storage unit A15 is different in operation from the first embodiment. Parts different from the first embodiment in each part will be described.

  A different point from the first embodiment of the slot management unit A11 is that, when the time slot assignment is overwritten, information on which time slot is overwritten to the information stored in the slot change information storage unit A15 is additionally stored. It is.

  Similar to the first embodiment, when the slot management unit A11 receives a slot request signal from the wireless communication unit A10, the slot management unit A11 determines a time slot to be assigned to the terminal of the slot request signal transmission source. Further, the slot management unit A11 notifies the determined time slot by the slot assignment signal, and stores it in the slot assignment storage unit A14.

  Thereafter, reference is made to the slot assignment erased information held by the slot change information storage unit A15. As a result of this reference, when the slot allocation erased information includes the selected time slot, the slot management unit deletes the slot allocation erased information and stores the slot overwrite timing information. Furthermore, in the second embodiment, in addition to the slot overwrite timing information, information (slot overwrite position information) indicating which slot has been overwritten, which is generated based on the deleted slot assignment erased information is stored. Do. At this time, slot overwrite timing information and slot overwrite position information are stored in combination.

  In this embodiment, it is assumed that the number of the time slot of the deleted slot assignment erased information is stored as the slot overwrite position information. However, this may be other types of information as long as it is based on the slot number of the deleted slot assignment erased information. For example, a set of non-overlapping time slots may be defined, and the identifier of the set may be stored. A method of determining a set of time slots is shown in FIG. In this example, the frame is divided into eight time slots 0 to 7, and two time slot sets T1 and T2 are defined from the eight time slots. The time slot sets T1 and T2 correspond to the identifiers of the time slot set described above. In this example, eight time slots are used, but the number of time slots is not limited. Also, the number of time slot sets is not limited, and there is no limit on how to define the sets.

  Although described in detail in the slot change information notification unit A13 in the second embodiment, in the present embodiment, information in an amount proportional to the number of different slot overwrite position information is included in the beacon and transmitted. Therefore, when a set of time slots is defined and the identifier is defined as slot overwrite position information, the variation of the slot overwrite position information decreases, so the amount of information that must be included in the beacon when the slot overwrite position information increases. There is less However, when the slot overwrite position information is used as an identifier of a time slot set, the granularity of information indicating which time slot has been overwritten becomes coarse.

  The slot change information notification unit A13 generates a beacon based on the slot overwrite timing information and the slot overwrite position information stored in the slot change information storage unit A15, and transmits the beacon via the wireless communication unit A10.

  In the second embodiment, first, slot overwrite position information stored in the slot change information storage unit A15 is extracted. Thereafter, the newest slot overwrite timing information is extracted for each of the extracted slot overwrite position information, and a pair of corresponding slot overwrite position information and slot overwrite timing information is generated. A set of generated sets of slot overwrite position information and slot overwrite timing information is included in the beacon and transmitted via the wireless communication unit A10. This process is performed at a predetermined cycle as in the first embodiment.

  In the present embodiment, although a set of generated slot overwrite position information and slot overwrite timing information is all included in a single beacon, the present invention is not limited to this. The generated set of slot overwrite position information and slot overwrite timing information may be divided into a plurality of beacons. In that case, the processing in the continuous use determination unit A'13 of the general terminal A'1 is not the case where a single beacon is received, but a plurality of beacons are received, and all slot overwrite position information and slot overwrite timing information It will be done when you have received the pair. The processing in the continuous use determination unit A ′ 13 of the general terminal A ′ 1 in the second embodiment will be described later.

  The slot change information storage unit A15 stores slot overwrite position information in the second embodiment in addition to the slot assignment erased information notified from the slot management unit A11 and the slot overwrite timing information. These pieces of information are referred to by the slot management unit A11, the disconnection / return detection unit A12 of the general terminal, and the slot change information notification unit A13.

  The configuration of the general terminal A′1 in the second embodiment is shown in FIG. 5 as in the first embodiment. Among these, the processing of the continuous use determination unit A ′ 13 is different from that of the first embodiment.

  When the own terminal is not present in the network and the beacon is received, the continued use determining unit A ′ 13 determines whether to continue using the time slot used in the past. At this time, in the second embodiment, it is determined based on not only the slot overwrite timing information included in the beacon but also the slot overwrite position information whether to use continuously.

  The process after determining whether to continue using is the same as that of the first embodiment. When the continuous use is possible, the invalidation flag of the slot information storage unit A'14 is deleted. If the continuous use is not possible, the subscription processing unit A'11 is notified that the continuous use is not possible.

  The details of the determination as to whether to continue using in the continuous use determining unit A ′ 13 of the second embodiment will be described. The continued use determination unit A'13 is notified of the reception of a beacon from the wireless communication unit A'10 in the state where the invalidation flag is added to the allocated slot information of the slot information storage unit, as in the first embodiment. Only do processing. The continued use determining unit A ′ 13 first refers to the slot overwrite position information included in the beacon received by the slot information storage unit A ′ 14. Slot overwrite timing information and slot information storage unit A ′ 14 are included if the slot overwrite position information is the same as the time slot information stored in the slot information storage unit A ′ 14 with the invalid flag added. Compare network departure times. If the slot overwrite timing information is older, it is determined that it can be continuously used. If not, it is determined that the continuous use is not possible.

  As described above, the slot overwrite position information may be not a time slot number but an identifier of a time slot set. In that case, if the time slot set indicated by the slot overwrite position information includes the time slot number of the time slot information stored with the invalid flag added to the slot information storage unit A'14, the slot overwrite timing information And compare the time of network departure.

  In addition, as described above, the set of slot overwrite position information and slot overwrite timing information may be divided into a plurality of beacons, in which case reception of beacons is continued until all divided information is acquired. May be

[Description of operation]
Next, the operation of the second embodiment will be described with reference to FIG. 13, FIG. 14, and FIG. In addition, description is abbreviate | omitted regarding the process which performs the same operation | movement as 1st Embodiment similarly to description of a structure.

  The present embodiment differs from the first embodiment in the processing of assigning a slot to the general terminal A ′ 1 that is about to join the network and the processing of transmitting a beacon, as compared with the first embodiment.

  The operation of the process of assigning a slot to the general terminal A'1 which is going to join the network will be described. This operation differs from the first embodiment only in the slot determination process (step S201).

  A flow of processing for assigning a slot to the general terminal A'1 which is going to join the network is shown in FIG. The slot determination process (step S201) is performed in the slot management unit A11. A slot to be allocated to the terminal of the slot request signal transmission source is determined, and slot allocation information D00 is generated, and this slot allocation information D00 is stored in the slot allocation storage unit A14. When the determined slot is stored in the slot change information storage unit A15 as the slot assignment erased information D11, slot overwrite timing information D01 is generated and stored in the slot change information storage unit A15. At this time, in the second embodiment, in addition to the slot overwrite timing information D01, slot overwrite position information D02 is generated and stored in the slot change information storage unit A15.

  A flow of beacon transmission processing is shown in FIG. The process of transmitting a beacon is a process in which the beacon generation process (step S220) is different from that of the first embodiment. The beacon generation process (step S220) is performed in the slot change information notification unit A13. In the beacon generation process (step S220), a beacon is generated based on the slot overwrite timing information D01 and the slot overwrite position information D02.

  In this embodiment, the general terminal A′1 differs from the first embodiment in the processing for the general terminal to join the network. A flow of processing for joining a network is shown in FIG. In particular, among the processes for joining the network, the continuous use determination process (step S'204) is different.

  Similar to the first embodiment, the continuous use determination unit A'13 performs the continuous use determination process (step S'204) in the present embodiment. When the time slot information D'01 is included in the received overwrite slot position information, the slot can be continuously used based on the network departure time D'00 and the slot overwrite timing information included in the received beacon. Make a decision.

[Description of effect]
Next, the effects of the present embodiment will be described. In the present embodiment, as in the first embodiment, the management terminal A1 transmits a beacon including the time when the slot was last overwritten. As a result, it is possible to determine whether the general terminal A′1 that has temporarily left the network can continue to use the slot it has used in the past. Therefore, it is possible to rejoin the network using the previously used slot again without transmitting the slot request signal. Also, since the management terminal A1 can check that the general terminal A'1 has returned to the network by utilizing the path control information, it is possible to return the general terminal A'1 without generating a control signal additionally. At the same time, the slot assignment information on the management terminal can be updated. In this manner, according to the present embodiment, the effect of reducing control signals when a terminal that has temporarily left the network returns to the network can be obtained.

  Further, as in the first embodiment, when a terminal that has been temporarily left is restored, the terminal itself is not transmitted in the past without waiting for transmission of a slot request signal to the management terminal or reception of a slot assignment signal. It can communicate using the time slot to which was allocated. That is, when a terminal that has temporarily left the network returns to the network, it becomes unnecessary to transmit a slot request signal to the management terminal managing the time slot, and slot assignment from the management terminal managing the time slot becomes There is no need to wait to receive a signal. Therefore, according to the present embodiment, when a terminal that has been temporarily disconnected returns to the network, communication can be started in a short time.

  Further, in the second embodiment, it is possible to determine whether the terminal that returns to the network continues to use the past time slot more in line with the slot allocation status managed by the management terminal A1. Therefore, there are many cases where the effects of reducing control signals when returning to the network and shortening the time until communication becomes possible can be obtained.

  In the first embodiment, a single slot overwrite timing is included in the beacon, and when any one of the time slot set is overwritten, the slot overwrite timing information included in the beacon is changed. It was Therefore, when a certain terminal returns to the network, even if a slot that the terminal has used in the past is still usable, if the other slot is overwritten, it is determined that the continuous use is not possible. I was judging.

  In the second embodiment, information on the number of the overwritten time slot and the overwritten timing is included in the beacon. Therefore, even in the case where the slot used by another terminal in the past is overwritten, if the slot used by the own terminal is not overwritten, it may be determined that the time slot can be used continuously. It becomes possible. As described above, in the present embodiment, the number of cases where the effects of reducing control signals when returning to the network and shortening the time until communication become possible can be obtained can be increased as compared to the first embodiment.

Other Embodiments
As mentioned above, although the preferable embodiment of this invention was described, this invention is not limited to this. For example, as shown in FIG. 16, the management terminal A1 of the first embodiment and the second embodiment can also be configured to include a wireless communication unit A10 and a CPU (central processing unit) A20. The functions of the slot management unit A11 of the management terminal A1 of FIG. 4, the disconnection / return detection unit A12 for general terminals, the slot change information notification unit A13, the slot allocation storage unit A14, or the slot change information storage unit A15 are also realized by software. It can be done. That is, the program may also be implemented by a program that causes the CPU A 20 as an example of a computer to execute slot management processing of the slot management unit A11 or separation / return detection processing of a general terminal separation / restoration detection unit A12. The program may also be implemented by a program that causes the CPU A 20 as an example of a computer to execute slot change information notification processing of the slot change information notification unit A 13. The program may also be implemented by a program that causes the CPU A 20 as an example of a computer to execute the slot assignment storage process of the slot assignment storage unit A 14 or the slot change information storage process of the slot change information storage unit A 15.

  Also, as shown in FIG. 17, the general terminal A′1 of the first embodiment and the second embodiment can also be configured to include a wireless communication unit A′10 and a CPU A′20. The functions of the subscription processing unit A'11, the connection state determination unit A'12, the continuous use determination unit A'13, or the slot information storage unit A'14 of the general terminal A'1 of FIG. 5 can also be realized by software. . That is, the program may be realized by a program that causes the CPU A ′ 20 as an example of a computer to execute the joining process of the joining processing unit A ′ 11 or the connection state determination process of the connection state determination unit A ′ 12. The program can also be implemented by a program that causes the CPU A ′ 20 as an example of a computer to execute the slot information storage process of the slot information storage unit A ′ 14 or the continuous use determination process of the continuous use determination unit A ′ 13. It is needless to say that various modifications are possible within the scope of the invention described in the claims, and they are also included in the scope of the present invention.

Some or all of the above embodiments may be described as in the following appendices, but are not limited to the following.
(Supplementary Note 1) A wireless communication system, comprising: a management terminal having a function of allocating communication resources to each terminal constituting the wireless communication system; and other terminals to which the communication resources are allocated,
The management terminal is
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed;
A means for determining whether the terminal to which the own terminal has allocated communication resources in the past can communicate with the own terminal;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Means for considering that communication resources are allocated to the terminal when communication is possible.
(Supplementary Note 2) The other terminals to which the communication resources are allocated are:
A means for determining whether the own terminal can communicate with the management terminal;
A means for recording information on communication resources allocated in the past by the own terminal and information based on timing when the own terminal can no longer communicate with the management terminal;
Means for determining whether to request the management terminal to allocate the communication resource used by the own terminal based on a signal including an identifier indicating that the allocation of the communication resource transmitted by the management terminal has changed Wireless communication system as described.
(Supplementary Note 3) A wireless communication system, including a management terminal having a function of allocating communication resources to each terminal constituting the wireless communication system, and other terminals to which communication resources are allocated,
The management terminal is
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed and an identifier of the communication resources whose allocation has changed;
A means for determining whether the terminal to which the own terminal has allocated communication resources in the past can communicate with the own terminal;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Means for considering that communication resources are allocated to the terminal when communication is possible.
(Supplementary Note 4) The other terminals to which the communication resources are assigned include
A means for determining whether the own terminal can communicate with the management terminal;
A means for recording information on communication resources allocated in the past by the own terminal and information based on timing when the own terminal can no longer communicate with the management terminal;
Whether to request the management terminal to allocate the communication resource used by the own terminal based on the signal transmitted by the management terminal including the identifier indicating that the allocation of the communication resource has changed and the identifier of the communication resource whose allocation has changed APPENDIX 3. The wireless communication system according to appendix 3, comprising:
(Supplementary Note 5) The wireless communication system according to Supplementary Note 3 or 4, wherein the identifier of the communication resource whose assignment has been changed is an identifier of each group obtained by grouping the communication resource.
(Supplementary note 6) The wireless communication system according to any one of supplementary notes 1 to 5, wherein the identifier indicating that the allocation of the communication resource has changed is information that can define an order relation.
(Supplementary note 7) The identifier according to any one of supplementary notes 1 to 6, wherein the identifier indicating that the allocation of the communication resource has changed is information indicating an elapsed time from the timing when the allocation of the communication resource has changed last. Wireless communication system.
(Supplementary note 8) In any one of supplementary notes 1 to 7, that the allocation of the communication resource has changed is that the management terminal allocates the communication resource, which has been allocated to any terminal in the past, to another terminal. Wireless communication system as described.
(Supplementary note 9) The wireless communication system according to any one of supplementary notes 1 to 8, wherein the communication resource is timing at which a terminal transmits a signal.
(Supplementary note 10) Any one of supplementary notes 1 to 9, wherein the terminal to which the own terminal has allocated communication resources in the past is a means for determining whether communication with the own terminal is possible other than the request for communication resources. Wireless communication system according to the above.
(Supplementary note 11) The wireless communication system according to supplementary note 10, wherein the means other than the request for communication resources is means for determining that communication with the terminal is possible if a route exists based on the route control information.
(Supplementary note 12) There is a function of assigning communication resources to each terminal constituting the wireless communication system,
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed;
A means for determining whether communication with a terminal constituting the wireless communication system, which has been allocated communication resources in the past, is possible;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Means for considering that communication resources are allocated to the terminal when communication is possible.
(Supplementary note 13) There is a function of assigning communication resources to each terminal constituting the wireless communication system,
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed and an identifier of the communication resources whose allocation has changed;
A means for determining whether communication with a terminal constituting the wireless communication system, which has been allocated communication resources in the past, is possible;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Means for considering that communication resources are allocated to the terminal when communication is possible.
(Supplementary note 14) The wireless communication apparatus according to supplementary note 13, wherein the identifier of the communication resource whose assignment has been changed is an identifier of each group obtained by grouping the communication resource.
(Supplementary note 15) The wireless communication apparatus according to any one of supplementary notes 12 to 14, wherein the identifier indicating that the allocation of the communication resource has changed is information that can define an order relation.
(Supplementary note 16) The identifier according to any one of supplementary notes 12 to 15, wherein the identifier indicating that the allocation of the communication resource has changed is information indicating an elapsed time from the timing when the allocation of the communication resource has changed last. Wireless communication device.
(Supplementary note 17) The radio according to any one of supplementary notes 12 to 16, wherein the change of the allocation of the communication resource is allocating the communication resource, which has been allocated to any terminal in the past, to another terminal Communication device.
(Supplementary note 18) The wireless communication apparatus according to any one of supplementary notes 12 to 17, wherein the communication resource is a timing at which a terminal transmits a signal.
(Supplementary note 19) The wireless communication apparatus according to any one of supplementary notes 12 to 18, wherein the means for determining whether communication with a terminal to which communication resources have been allocated in the past is communicable is a means other than a request for communication resources. .
(Supplementary note 20) The wireless communication apparatus according to supplementary note 19, wherein the means other than the request for communication resources is means for determining that communication with the terminal is possible if a route exists based on the route control information.
(Supplementary Note 21) A control method of a wireless communication apparatus for allocating communication resources to each terminal constituting a wireless communication system,
Transmitting a signal including an identifier indicating that the allocation of the communication resource has changed;
It is determined whether communication is possible with a terminal constituting the wireless communication system, to which communication resources have been allocated in the past, as a destination.
As a result of the determination, if communication is possible, it is considered that the communication resource is not allocated to the terminal, and if communication is not possible, it is considered that the communication resource is not allocated to the terminal. Control method of wireless communication device.
(Supplementary note 22) A control program of a wireless communication apparatus for assigning communication resources to terminals constituting a wireless communication system, the computer comprising
A process of transmitting a signal including an identifier indicating that the allocation of the communication resource has changed;
A process of determining whether communication is possible with the terminal constituting the wireless communication system, to which communication resources have been allocated in the past, as a destination, and as a result of the above determination, if communication is possible, communication resources are transmitted to the terminal A control program of a wireless communication apparatus, which assumes that the terminal is not assigned, and performs processing of regarding that the communication resource is not assigned to the terminal if communication is impossible.

N1 network
A1 Management terminal
A10 Wireless Communication Unit
A11 Slot Manager
A12 Disconnection / return detection unit of general terminal
A13 Slot change information notifier
A14 Slot allocation storage unit
A15 Slot change information storage unit
A20 CPU
A'1 general terminal
A'10 wireless communication unit
A'11 Subscription processing unit
A'12 Connection status judgment unit
A'13 Continuous Use Judgment Department
A'14 Slot Information Storage Unit
A'20 CPU

Claims (9)

A wireless communication system, comprising: a management terminal having a function of allocating communication resources to each terminal constituting the wireless communication system; and other terminals to which the communication resources are allocated,
The management terminal is
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed;
A means for determining whether the terminal to which the own terminal has allocated communication resources in the past can communicate with the own terminal;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Have a means regarded as a communication resource to the terminal is assigned when communication is possible,
The means for judging whether the management terminal can communicate with the own terminal is based on the route control information, and if the route exists, it can communicate with the terminal to which the own terminal has allocated communication resources in the past Wireless communication system to judge . Other terminals to which the communication resources are assigned are:
A means for determining whether the own terminal can communicate with the management terminal;
A means for recording information on communication resources allocated in the past by the own terminal and information based on timing when the own terminal can no longer communicate with the management terminal;
And a means for determining whether to request the management terminal to allocate the communication resources used by the own terminal based on a signal including an identifier indicating that the allocation of the communication resource transmitted by the management terminal has changed. The wireless communication system according to. A wireless communication system, comprising: a management terminal having a function of allocating communication resources to each terminal constituting the wireless communication system; and other terminals to which communication resources are allocated,
The management terminal is
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed and an identifier of the communication resources whose allocation has changed;
A means for determining whether the terminal to which the own terminal has allocated communication resources in the past can communicate with the own terminal;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Have a means regarded as a communication resource to the terminal is assigned when communication is possible,
Other terminals to which the communication resources are assigned are:
A means for determining whether the own terminal can communicate with the management terminal;
A means for recording information on communication resources allocated in the past by the own terminal and information based on timing when the own terminal can no longer communicate with the management terminal;
Whether to request the management terminal to allocate the communication resource used by the own terminal based on the signal transmitted by the management terminal including the identifier indicating that the allocation of the communication resource has changed and the identifier of the communication resource whose allocation has changed Means to judge
To have the bets, a wireless communication system. The wireless communication system according to claim 3 , wherein the identifier of the communication resource whose assignment has changed is an identifier of each group obtained by grouping the communication resource. The wireless communication system according to any one of claims 1 to 4 , wherein the identifier indicating that the allocation of the communication resource has changed is information capable of defining an order relation. The wireless communication system according to any one of claims 1 to 5 , wherein the identifier indicating that the allocation of the communication resource has changed is information indicating an elapsed time from a timing at which the allocation of the communication resource has finally changed. . Has a function of allocating communication resources to each terminal constituting the wireless communication system,
Means for transmitting a signal including an identifier indicating that the allocation of communication resources has changed;
A means for determining whether communication with a terminal constituting the wireless communication system, which has been allocated communication resources in the past, is possible;
A means for assuming that communication resources are not allocated to the terminal when communication is impossible;
Have a means regarded as a communication resource to the terminal is assigned when communication is possible,
The means for determining whether communication with a terminal constituting the wireless communication system which has allocated communication resources in the past can be performed based on the path control information, and if there is a path, the means for determining communication resources in the past A wireless communication device that determines that it is possible to communicate with a terminal that configures the wireless communication system. A control method of a wireless communication apparatus for assigning communication resources to each terminal constituting a wireless communication system,
Transmitting a signal including an identifier indicating that the allocation of the communication resource has changed;
It is determined whether communication is possible with a terminal constituting the wireless communication system, to which communication resources have been allocated in the past, as a destination.
Result of the above determination, the the terminal assumes that the communication resources that are assigned, all said to those not communication resource is allocated to the terminal when it is unable to communicate when communication is possible ,
The determination as to whether the terminal constituting the wireless communication system which has allocated the communication resource in the past can communicate with the other party is the communication resource in the past if the route exists based on the route control information. And a control method of a wireless communication apparatus, which determines that communication with a terminal configuring the wireless communication system is possible . A control program of a wireless communication apparatus for assigning communication resources to each terminal constituting a wireless communication system,
On the computer
A process of transmitting a signal including an identifier indicating that the allocation of the communication resource has changed;
A process of determining whether communication is possible with a terminal constituting the wireless communication system, to which communication resources have been allocated in the past, and as a result of the above determination, if communication is possible, communication resources are transmitted to the terminal It assumed that that is assigned, if it is unable to communicate are those to perform the processing viewed as no communication resource is allocated to the terminal,
The process of determining whether communication is possible with the terminal constituting the wireless communication system which has allocated communication resources in the past as the destination is communication based on the route control information, if there is a route, the communication is performed in the past A control program of a wireless communication apparatus, which determines that communication with a terminal constituting the wireless communication system, which has been allocated resources, is possible .

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