JP7254419B2 - Wireless communication method, program and coordinator device - Google Patents

Description

The present invention relates to wireless communication technology, and more particularly to wireless communication technology that allocates a plurality of wireless LAN systems to the same channel and appropriately controls traffic transmission timing.

In recent years, the full-scale IoT (Internet of Things) era has arrived, and IoT technology is being utilized in various fields such as manufacturing and infrastructure. For example, in a factory, an IoT device is attached to a manufacturing system such as robots and machines, and operation status grasping, control, and quality control of the devices and machines are performed via a wireless LAN (Local Area Network). On the other hand, in a factory where many manufacturing systems are densely arranged, multiple wireless devices attempt to communicate at the same time, which causes frequent packet collisions, resulting in packet loss and delay.

Techniques for avoiding packet collision include allocation of channels to be used, interference detection, channel change when interference is detected, and transmission power control. For example, it is conceivable to change the channel to be used using the technology described in Patent Document 1.

Assuming control using a centralized control device (e.g., controller), a control device is prepared, and an access point (AP) of a wireless LAN system to be controlled is, for example, centralized via a network. Connect to controller. The control device can prevent the occurrence of packet collision by performing the above-described control on the AP connected to the centralized control device.

Japanese Unexamined Patent Application Publication No. 2013-93708

However, when the above technology is used, if there are many wireless LAN systems, channels overlap on the frequency axis, causing inter-system interference. Under such circumstances, when traffic is transmitted by the wireless LAN system, many collisions occur, necessitating retransmission, and as a result, it becomes difficult to transmit the traffic within the allowable delay time of the traffic. . In other words, in the situation described above, it is difficult to appropriately control the traffic transmission timing when using the above technique.

Therefore, in view of the above problems, the present invention appropriately controls the transmission timing of traffic even in a narrow space where a large number of wireless communication terminals are present. It is an object of the present invention to realize a wireless communication method and a program that are executed in a wireless communication system capable of performing high-precision wireless communication.

In order to solve the above problems, a first invention is a radio system including one or a plurality of radio communication devices, and a radio communication method used in a radio communication system including a plurality of radio systems. The wireless communication method includes a time slot definition step, a data collection step, a counter value setting step, a traffic number setting step, a determination step, a traffic adjustment step, a time slot allocation information generation step, a wireless communication step, Prepare.

The time slot definition step is a time slot definition step for defining a time slot for common use among a plurality of wireless systems, and determines the slot length and slot start time of the time slot.

The data collection step collects from the wireless communication device traffic data, which is data regarding transmission timing of traffic that the wireless communication device is going to transmit and data regarding allowable delay.

The counter value setting step sets a counter value defined by the number of time slots for each traffic to be transmitted by the wireless communication device.

The traffic number setting step sets the same time slot transmission traffic number, which is the number of traffic to be transmitted in one time slot.

The determining step determines whether or not the number of traffic candidates for transmission in one time slot is equal to or less than the same time slot transmission traffic number.

The traffic adjustment step determines traffic to be transmitted in one time slot based on the determination result of the determination step.

The time slot assignment information generation step is performed based on communication-related information of at least one of the wireless system and the wireless communication device and information about traffic to be transmitted in one time slot determined by the traffic adjustment step, and a plurality of Time slot assignment information, which is information on time slots to be assigned to each wireless communication device included in the wireless system, is generated.

In the wireless communication step, the wireless communication device assigned by the time slot assignment information performs wireless communication using the channel used in the wireless communication system during the period specified by the time slot assigned by the time slot assignment information. .

In this wireless communication method, by using time slots commonly defined based on information (information indicating communication status, information indicating communication performance, etc.) of all devices included in the wireless communication system, one channel can be radio systems can be used in time division. Further, in this wireless communication method, for traffic that each communication device is about to transmit, for example, a counter value considering transmission timing and allowable delay amount, which is represented by an integer value in units of time slot length. A value is set and the traffic to be transmitted in each time slot is identified based on the counter value. In other words, in this wireless communication method, by introducing a counter value represented by an integer value in units of the time slot length, the combinatorial optimization problem of at what timing each time slot should be transmitted can be easily solved. method. Then, in this wireless communication method, the traffic to be transmitted in each time slot is determined based on the solution thus obtained (solution of the combinatorial optimization problem). Therefore, in a radio communication system that executes this radio communication method, it is possible to appropriately control traffic transmission timing even in a narrow space where many radio communication devices exist. As a result, in a wireless communication system that executes this wireless communication method, high-speed and high-precision wireless communication can be performed without deteriorating wireless communication performance.

A second invention is the first invention, wherein the counter value setting step sets the initial value of the counter value based on the number of time slots corresponding to the allowable delay amount of traffic that the wireless communication device is trying to transmit. do.

Thereby, in this wireless communication method, the initial value of the counter value of each traffic can be set to the number of time slots corresponding to the allowable delay amount of the traffic.

A third invention is the first or second invention, wherein the traffic adjustment step selects traffic that is a candidate for traffic to be transmitted in one time slot and is selected as traffic to be transmitted in the time slot. Update the counter value of the traffic that was not passed to the value decremented by one.

As a result, in this wireless communication method, by checking the counter value of each traffic, it is possible to grasp how much time remains before the allowable delay amount in units of the number of time slots.

A fourth invention is any one of the first to third inventions, wherein the determination step determines that the number of traffic candidates for transmission in one time slot is not equal to or less than the same time slot transmission traffic number. If it is determined, the traffic adjustment step sorts the counter values of traffic candidates for transmission in one time slot, and transmits in one time slot based on the result of the sorting process. determine the traffic that should be

Thus, in this wireless communication method, traffic to be transmitted in one time slot can be appropriately selected based on the result of sorting the counter values of traffic candidates for transmission in one time slot. can be done.

A fifth invention is any one of the first to fourth inventions, wherein the determination step determines that the number of traffic candidates for transmission in one time slot is not equal to or less than the same time slot transmission traffic number. If it is determined, the traffic adjustment step sorts the allowable delay amount of traffic that is a candidate for transmission in one time slot, and transmits in one time slot based on the result of the sorting process determine the traffic that should be

Thus, in this wireless communication method, traffic to be transmitted in one time slot is appropriately selected based on the result of sorting processing of the allowable delay amount of traffic that is a candidate for transmission in one time slot. be able to.

A sixth invention is any one of the first to fifth inventions, wherein the determination step determines that the number of traffic candidates for transmission in one time slot is not equal to or less than the same time slot transmission traffic number. If it is determined, the traffic adjustment step performs sorting processing on priority labels indicating the communication priority of traffic that is a candidate for transmission in one time slot, and based on the result of the sorting processing, Determine the traffic to be transmitted in one timeslot.

Thus, in this wireless communication method, traffic to be transmitted in one time slot is appropriately selected based on the result of sorting processing of priority labels of traffic candidates for transmission in one time slot. be able to.

A seventh invention is the sixth invention, further comprising an input step of inputting data for setting the value of the priority label. The value of the priority label is set based on the data entered by the input step.

Thereby, in this wireless communication method, the value of the priority label can be, for example, a variable value.

An eighth invention is the sixth or seventh invention, wherein the value of the priority label is set such that the higher the priority of the traffic, the greater the amount of data to be transmitted.

Thus, in this wireless communication method, traffic with a large number of transmission data is more likely to be preferentially transmitted, and as a result, communication by traffic with a large number of transmission data is more appropriately ensured.

A ninth invention is any one of the first to eighth inventions, wherein the traffic number setting step sets a same time slot transmission traffic number, which is the number of traffic to be transmitted in one time slot, to a fixed value.

As a result, in this wireless communication method, it is possible to select the traffic to be transmitted in one time slot using the same time slot transmission traffic number as a fixed value.

A tenth invention is any one of the first to eighth inventions, wherein the traffic number setting step sets the same time slot transmission traffic number, which is the number of traffic to be transmitted in one time slot, to be different between the time slots. set to a value.

Thus, in this radio communication method, the traffic to be transmitted in one time slot can be selected by making the number of same-time-slot transmission traffic variable between time slots.

An eleventh invention is a program according to any one of the first to tenth inventions, which causes a computer to execute the wireless communication method.

Thereby, it is possible to realize a program having the same effect as the wireless communication method according to any one of the first to tenth inventions.

A twelfth invention is a radio system each including one or a plurality of radio communication devices, and is a coordinator apparatus used in a radio communication system including a plurality of radio systems. The coordinator device includes a time slot definition unit, a radio system information acquisition/holding unit, a counter value setting unit, a traffic adjustment processing unit, a time slot allocation information generation unit, a first communication processing unit, and a first communication interface. , provided.

The time slot definition section is a time slot definition section that defines a time slot for common use among a plurality of wireless systems, and determines the slot length and slot start time of the time slot.

The wireless system information acquisition/holding unit collects traffic data, which is data on transmission timing and data on allowable delay of traffic to be transmitted by the wireless communication device, from the wireless communication device.

The counter value setting unit sets a counter value defined by the number of time slots for each traffic that the wireless communication device is trying to transmit.

The traffic adjustment processing unit (1) sets the number of same-time-slot transmission traffic, which is the number of traffic to be transmitted in one time slot, and (2) sets the number of traffic candidates for transmission in one time slot. (3) Based on the determination result, determine the traffic to be transmitted in one time slot.

The time slot allocation information generation unit generates a plurality of time slot assignment information, which is information on time slots to be assigned to each of the wireless communication devices included in the wireless system.

The first communication processing unit performs wireless communication using a channel used in a wireless communication system by a wireless communication device assigned by the time slot assignment information during a period specified by the time slots assigned by the time slot assignment information. Get the data to do

The first communication interface is a communication interface for transmitting data acquired by the first communication processing unit to each wireless communication device.

Thereby, a coordinator device having the same effect as the first invention can be realized.

According to the present invention, even in a narrow space where a large number of wireless communication terminals exist, by appropriately controlling the transmission timing of traffic, high-speed and high-precision communication can be performed without degrading wireless communication performance. A wireless communication method and program executed in a wireless communication system capable of wireless communication can be realized.

1 is a schematic configuration diagram of a wireless communication system 1000 according to a first embodiment; FIG. 1 is a schematic configuration diagram of a coordinator device 100 according to a first embodiment; FIG. 2 is a schematic configuration diagram of a first access point AP1-1 according to the first embodiment; FIG. 2 is a schematic configuration diagram of a wireless terminal STA1-1 according to the first embodiment; FIG. FIG. 2 is a sequence diagram for explaining processing executed in the wireless communication system 1000; FIG. FIG. 2 is a sequence diagram for explaining processing executed in the wireless communication system 1000; FIG. FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr4 (time slot allocation process) (when N=1); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr4 (time slot allocation process) (when N=1); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr4 (time slot allocation process) (when N=1); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr4 (time slot allocation process) (when N=1); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr4 (time slot allocation process) (when N=1); FIG. 4 is a diagram showing a data format (one example) of time slot allocation information and a correspondence table between connected devices and node IDs; The figure which shows the data format (an example) of time slot allocation information. FIG. 2 is a schematic configuration diagram of a radio communication system 2000 according to a second embodiment; The schematic block diagram of 100 A of coordinator apparatuses which concern on 2nd Embodiment. FIG. 10 is a diagram showing the data structure of data D_slot used in the wireless communication system 2000 of the second embodiment; FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr5 (time slot allocation process) (when N=2); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr5 (time slot allocation process) (when N=2); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr5 (time slot allocation process) (when N=2); FIG. 10 is a diagram for explaining the process of determining time slots for transmitting traffic Tr1 to Tr5 (time slot allocation process) (when N=2); A diagram for explaining the process of determining time slots for transmitting the traffic Tr1 to Tr5 (time slot assignment process) (when N=2, the process by priority label) A diagram for explaining the process of determining time slots for transmitting the traffic Tr1 to Tr5 (time slot assignment process) (when N=2, the process by priority label) A diagram for explaining the process of determining time slots for transmitting the traffic Tr1 to Tr5 (time slot assignment process) (when N=2, the process by priority label) FIG. 4 is a diagram for explaining traffic selection processing in the same time slot (when N=4); FIG. 4 is a diagram showing a CPU bus configuration;

[First embodiment]
A first embodiment will be described below with reference to the drawings.

<1.1: Configuration of wireless communication system>
FIG. 1 is a schematic configuration diagram of a radio communication system 1000 according to the first embodiment.

FIG. 2 is a schematic configuration diagram of the coordinator device 100 according to the first embodiment.

FIG. 3 is a schematic configuration diagram of the first access point AP1-1 according to the first embodiment.

FIG. 4 is a schematic configuration diagram of the wireless terminal STA1-1 according to the first embodiment.

The radio communication system 1000, as shown in FIG. 1, includes a coordinator device 100, a first radio system SYS1, a second radio system SYS2, and a third radio system SYS3. The coordinator device 100, the first wireless system SYS1, the second wireless system SYS2, and the third wireless system SYS3 are each connected to a network NW1 (for example, a wired network) as shown in FIG. can communicate with each other.

Note that the radio communication system 1000 includes a plurality of radio systems, and for convenience of explanation, the case where the number of radio systems included in the radio communication system 1000 is "3" will be described below as an example. , but is not limited to this, and the number of wireless systems included in the wireless communication system 1000 may be a number other than "3".

(1.1.1: coordinator device)
As shown in FIG. 2, the coordinator device 100 includes a first communication interface 11, a first communication processing unit 12, a wireless system information acquisition/holding unit 13, a time slot definition unit 14, a counter value setting unit 15, A traffic adjustment processing unit 16 and a time slot allocation information generation unit 17 are provided.

The first communication interface 11 is a communication interface for transmitting and receiving data to and from an external device via the network NW1. The first communication interface 11 converts the data D11 output from the first communication processing unit 12 into data D1_out in a format that can be communicated via the network NW1, and transmits the data D1_out via the network NW1. The first communication interface 11 also receives data D1_in via the network NW1. The first communication interface 11 converts the received data D1_in into data D11 that can be processed by the first communication processing unit 12 and outputs the data D11 to the first communication processing unit 12 .

The first communication processing unit 12 outputs data D11 to the first communication interface 11 when transmitting data to the network NW1. Further, the first communication processing unit 12 receives data D11 from the first communication interface 11 when receiving data from the network NW1. Further, the first communication processing unit 12, from the data D11 input from the first communication interface 11, the information of each wireless system, the information of the access points included in each wireless system, the information of the wireless terminal, and/or the wireless communication Devices (access points and wireless terminals included in each wireless system are collectively referred to as "wireless communication devices"; the same shall apply hereinafter) data D12 containing information on the transmission timing and allowable delay amount of each traffic that the terminal is about to transmit. It acquires and outputs the acquired data D21 to the wireless system information acquisition/holding unit 13 . Further, the first communication processing unit 12 receives data D_slot_def output from the time slot definition unit 14 and data D_slot output from the time slot allocation information generation unit 17, and receives data including data D_slot_def and/or data D_slot. and outputs the generated data to the first communication interface 11 as data D11 (data for transmission).

The wireless system information acquisition/holding unit 13 receives the data D12 output from the first communication processing unit 12 . The wireless system information acquisition/holding unit 13 obtains from the data D12 information on each wireless system, information on access points included in each wireless system, information on wireless terminals, and/or information on each traffic to be transmitted by the wireless communication device. Get information about transmission timing and allowable delay. Radio system information acquisition/holding section 13 then outputs data including the acquired information to time slot definition section 14, counter value setting section 15, and time slot allocation information generation section 17 as radio system information Info_sys.

Time slot definition section 14 executes a process of defining time slots used in wireless communication system 1000 (time slot definition process). The time slot definition unit 14 receives the radio system information Info_sys output from the radio system information acquisition/holding unit 13, executes time slot definition processing based on the radio system information Info_sys, and defines (defines) time slots. The data necessary for this is obtained as data D_slot_def. Then, the time slot definition unit 14 outputs the acquired data D_slot_def to the counter value setting unit 15 and the first communication processing unit 12 . In addition, the time slot definition unit 14 acquires data D_slot_def necessary for defining a time slot as an initial value based on, for example, the initial state of the wireless communication system 1000 and the steady state of the wireless environment, and the acquired data D_slot_def is output to the first communication processing unit 12 and the counter value setting unit 15 .

The counter value setting unit 15 receives the radio system information Info_sys output from the radio system information acquisition/holding unit 13 and the data D_slot_def output from the time slot definition unit 14 . The counter value setting unit 15 sets a counter value Cnt(TrX) (TrX is a variable specifying traffic) for each traffic that the wireless communication device is trying to transmit based on the wireless system information Info_sys and the data D_slot_def. Specifically, the counter value setting unit 15 sets the counter value Cnt(TrX) based on the transmission timing of each traffic that the wireless communication device is trying to transmit and the allowable delay. Then, the counter value setting unit 15 outputs data including the transmission timing of each traffic and the counter value Cnt (TrX) to the traffic adjustment processing unit 16 as data D_cnt. Note that the counter value Cnt(TrX) indicates the counter value of the traffic TrX and is represented by an integer of 0 or more.

The traffic adjustment processing unit 16 receives the radio system information Info_sys output from the radio system information acquisition/holding unit 13 and the data D_cnt output from the counter value setting unit 15 . The traffic adjustment processing unit 16 executes traffic adjustment processing for specifying traffic to be transmitted in each time slot based on the transmission timing of each traffic that the wireless communication device is trying to transmit and the counter value Cnt(TrX). do. Then, the traffic adjustment processing unit 16 outputs data indicating the result of the traffic adjustment processing to the time slot allocation information generation unit 17 as data D_adj.

The time slot allocation information generation unit 17 receives the radio system information Info_sys output from the radio system information acquisition/holding unit 13 and the data D_adj output from the traffic adjustment processing unit 16 . Time slot allocation information generating section 17 generates time slot allocation information used in wireless communication system 1000 based on wireless system information Info_sys and data D_adj, and uses the generated time slot allocation information as data D_slot in the first Output to the communication processing unit 12 .

(1.1.2: First radio system)
The first wireless system SYS1, as shown in FIG. 1, comprises a first access point AP1-1 and two wireless terminals STA1-1 and STA1-2. Note that the first radio system SYS1 may include three or more radio terminals.

(1.1.2.1: First access point)
As shown in FIG. 3, the first access point AP1-1 includes a second communication interface 21, a second communication processing unit 22, an RF processing unit 23, a time slot information storage unit 24, and a wireless system information acquisition/holding unit. It comprises a unit 25 and an antenna Ant1.

The second communication interface 21 is a communication interface for transmitting and receiving data to and from an external device via the network NW1. The second communication interface 21 converts the data D21 output from the second communication processing unit 22 into data D2_out in a format that can be communicated via the network NW1, and transmits the data D2_out via the network NW1. The second communication interface 21 also receives data D2_in via the network NW1. The second communication interface 21 converts the received data D2_in into data D21 that can be processed by the second communication processing unit 22 and outputs the data D21 to the second communication processing unit 22 .

The second communication processing unit 22 outputs data D21 to the second communication interface 21 when transmitting data to the network NW1. Further, the second communication processing unit 22 receives data D21 from the second communication interface 21 when receiving data from the network NW1. The second communication processing unit 22 also acquires data D_slot including time slot allocation information from the data D21 input from the second communication interface 21 and outputs the acquired data D_slot to the time slot information storage unit 24 . Further, the second communication processing unit 22 acquires data D_slot_def including information for defining a time slot (time slot definition information) from the data D21 input from the second communication interface 21, and converts the acquired data D_slot_def into a time slot. Output to the slot information storage unit 24 . Further, the second communication processing unit 22 acquires data D23 including information on the first wireless system SYS1, which is the wireless system including the access point AP1-1, from the data D22 output from the RF processing unit 23, and acquires The obtained data D23 is output to the wireless system information acquisition/holding unit 25. FIG. The second communication processing unit 22 also receives the first wireless system information Info_sys (SYS1) output from the wireless system information acquisition/holding unit 25 .

The RF processing unit 23 receives the data D22 output from the second communication processing unit 22, performs RF processing for transmission (RF modulation processing, etc.) on the input data D22, and transmits the data through the antenna Ant1. Obtain an RF signal RF2_out that can be transmitted to the outside. Then, the RF processing unit 23 transmits the RF signal RF2_out to the outside via the antenna Ant1. Further, the RF processing unit 23 receives an RF signal RF2_in from the outside via the antenna Ant1, performs reception RF processing (RF demodulation processing, etc.) on the received RF signal RF2_in, and performs second communication processing. It acquires data D22 that can be processed by the unit 22 and outputs the acquired data D22 to the second communication processing unit 22 .

The time slot information storage unit 24 receives the data D_slot and/or the data D_slot_def output from the second communication processing unit 22 and stores the input data. The time slot information storage unit 24 also outputs the stored data D_slot and/or data D_slot_def to the second communication processing unit 22 in accordance with a command from the second communication processing unit 22 .

The wireless system information acquisition/holding unit 25 receives the data D23 output from the second communication processing unit 22, acquires the information Info_sys (SYS1) of the first wireless system SYS1 from the data D23, and stores the acquired information Info_sys (SYS1 ) is memorized (held). Further, the wireless system information acquisition/holding unit 25 outputs the stored (holding) information Info_sys (SYS1) to the second communication processing unit 22 in accordance with a command from the second communication processing unit 22 .

(1.1.2.2: wireless terminal)
As shown in FIG. 4, the wireless terminal STA1-1 includes an antenna Ant2, an RF processing unit 31, a third communication processing unit 32, a time slot information storage unit 33, and a wireless terminal information acquisition/holding unit 34. .

The RF processing unit 31 receives an RF signal RF3_in from the outside via the antenna Ant2, performs RF processing for reception (RF demodulation processing, etc.) on the received RF signal RF3_in, and outputs the third communication processing unit 32 acquires data D<b>31 that can be processed, and outputs the acquired data D<b>31 to the third communication processing unit 32 . Further, the RF processing unit 31 receives data D31 output from the third communication processing unit 32, performs RF processing for transmission (RF modulation processing, etc.) on the input data D31, and operates the antenna Ant2. obtain an RF signal RF3_out that can be transmitted externally via Then, the RF processing unit 31 transmits the RF signal RF3_out to the outside via the antenna Ant2.

The third communication processing unit 32 receives data D31 from the RF processing unit 31 when receiving data from the outside via the antenna Ant2, and sends data D31 to the RF processing unit 31 when transmitting data to the outside via the antenna Ant2. Data D31 is output. The third communication processing unit 32 acquires data D_slot including time slot allocation information from the data D31 input from the RF processing unit 31 and outputs the acquired data D_slot to the time slot information storage unit 33 . Further, the third communication processing unit 32 obtains data D_slot_def including information for defining a time slot (time slot definition information) from the data D31 input from the RF processing unit 31, and converts the obtained data D_slot_def into the time slot. Output to the information storage unit 33 . Further, the third communication processing unit 32 acquires data D32 including information on the wireless terminal STA1-1 from the data D31 output from the RF processing unit 31, and sends the acquired data D32 to the wireless terminal information acquisition/holding unit 34. Output. The third communication processing unit 32 also receives information Info_sys(STA1-1) of the wireless terminal STA1-1 output from the wireless terminal information acquisition/holding unit .

The second radio system SYS2 and the third radio system SYS3 have the same configuration as the first radio system SYS1. Also, the second access point AP2-1 of the second wireless system SYS2 has the same configuration as the first access point AP1-1. The third access point AP3-1 of the third wireless system SYS3 has the same configuration as the first access point AP1-1.

Also, the wireless terminal STA1-2 of the first wireless system SYS1, the wireless terminal STA2-1 and the wireless terminal STA2-2 of the second wireless system SYS2, and the wireless terminals STA3-1 and STA3-2 of the third wireless system SYS3 are , have the same configuration as the wireless terminal STA1-1.

<1.2: Operation of wireless communication system>
The operation of the radio communication system 1000 configured as above will be described below with reference to the drawings.

5 and 6 are sequence diagrams for explaining the processing executed in the wireless communication system 1000. FIG. The operation of the wireless communication system 1000 will be described below with reference to FIGS. 5 and 6. FIG.

(Step S1):
In step S<b>1 , time slot definition section 14 of coordinator device 100 executes a process of defining time slots used in wireless communication system 1000 (time slot definition process).

As an initial value, the time slot definition unit 14 acquires data D_slot_def necessary for defining time slots based on, for example, the initial state of the wireless communication system 1000 and the steady state of the wireless environment.

For example, when the wireless communication system 1000 is installed in a narrow space such as a factory, the steady state of the wireless environment of the first wireless system SYS1, the second wireless system SYS2, and the third wireless system SYS3 (for example, and the state of the radio environment when there is no movement of people), based on the steady state, the time slot definition unit 14 determines (1) time slots for use in a plurality of radio systems. Determine slot length and (2) slot start time. Then, the time slot definition unit 14 generates data D_slot_def including the determined (1) slot length and (2) slot start time, and transmits the generated data D_slot_def to the first communication processing unit 12 and the counter value setting unit 15 . output to

Note that the coordinator device 100, for example, collects information such as device information and communication status from wireless terminals included in each access point (access points AP1-1, AP2-1, and AP3-1) and each wireless system, Based on the collected information, (1) slot lengths of time slots and (2) slot start times for use in multiple wireless systems may be determined.

(Step S2):
In step S2, the coordinator device 100 executes processing (data collection processing) for collecting data from each wireless communication device. Specifically, the data collection process is executed as follows.

The coordinator device 100 uses the first communication processing unit 12 to generate data (request data) requesting information necessary for time slot allocation from each wireless system and wireless terminals included in each wireless system. The request data is transmitted to the first access point AP1-1, the second access point AP2-1, and the third access point AP3-1 via the first communication interface 11 and the network NW1.

The first access point AP1-1 receives the request data via the network NW1 and the second communication interface, and based on the request data, the wireless terminal STA1-1 included in the first wireless system and the wireless Data (request data) requesting information necessary for time slot allocation is generated from the terminal STA1-2, and the generated request data is sent to the wireless terminal STA1-1 and the wireless terminal STA1-1 via the RF processing unit 23 and the antenna Ant1. Send to terminal STA1-2.

The wireless terminal STA1-1 receives the RF signal including the request data transmitted from the first access point AP1-1, and performs RF processing for reception on the RF signal to obtain the request data. get. Then, based on the request data, the third communication processing unit 32 of the wireless terminal STA1-1 acquires the wireless terminal information Info_sys(STA1-1) held in the wireless terminal information acquiring/holding unit. The wireless terminal information Info_sys(STA1-1) includes traffic data, which is data regarding the transmission timing of the traffic that the wireless terminal STA1-1 is about to transmit and data regarding the allowable delay.

The wireless terminal STA1-1 performs RF processing for transmission on the wireless terminal information Info_sys (STA1-1) obtained above, and generates an RF signal including the wireless terminal information Info_sys (STA1-1). The wireless terminal STA1-1 then transmits the generated RF signal to the first access point AP1-1 via the antenna Ant2.

The first access point AP1-1 performs reception RF processing on the RF signal received from the wireless terminal STA1-1, and acquires data Info_sys (STA1-1) of the wireless terminal STA1-1. The second communication processing unit 22 of the first access point AP1-1 transmits the data Info_sys (STA1-1) of the wireless terminal STA1-1 to the coordinator device 100 via the second communication interface 21 and the network NW1.

The first communication processing unit 12 of the coordinator device 100 acquires data including data Info_sys (STA1-1) transmitted from the first access point AP1-1 via the network NW1 and the first communication interface 11 as data D12. do. The wireless system information acquisition/holding unit 13 acquires and holds the data Info_sys (STA1-1) of the wireless terminal STA1-1 from the data D12.

In this way, coordinator apparatus 100 acquires data (information required for time slot allocation) Info_sys (STA1-1) of wireless terminal STA1-1. Data (information required for time slot allocation) Info_sys (STA1-2) of the wireless terminal STA1-2 is also obtained by the same process as above.

Based on the request data from the coordinator device 100, the first access point AP1-1 also acquires data Info_sys (SYS1), which is information necessary for time slot allocation of the first wireless system. Specifically, the second communication processing unit 22 acquires data Info_sys (SYS1), which is information necessary for time slot allocation of the first wireless system, from the wireless system information acquisition/holding unit 25 . Data Info_sys (SYS1), which is information necessary for time slot allocation in the first radio system, includes, for example, packet generation cycle, packet generation timing, packet size, allowable delay, and ACK/NACK information used in the first radio system. and other data. Also, the wireless terminal information Info_sys (SYS1) includes traffic data, which is data regarding the transmission timing of the traffic that the access point AP1-1 is about to transmit and data regarding the allowable delay. Also, part or all of the data Info_sys (SYS1), which is information necessary for time slot allocation of the first wireless system, is acquired by executing data collection processing by the first access point AP1-1. There may be.

The first access point AP1-1 transmits data including data Info_sys (SYS1), which is information necessary for time slot allocation of the first wireless system acquired as described above, to the coordinator device 100 via the network NW1. Send.

The first communication processing unit 12 of the coordinator device 100 acquires data including data Info_sys (SYS1) transmitted from the first access point AP1-1 via the network NW1 and the first communication interface 11 as data D12. The wireless system information acquisition/holding unit 13 acquires and holds the data Info_sys (SYS1) of the wireless terminal STA1-1 from the data D12.

In the same manner as described above, the coordinator device 100 acquires information necessary for time slot allocation of the second radio system SYS2, the third radio system SYS3, and the radio terminals included therein.

That is, coordinator apparatus 100 acquires and holds information necessary for time slot allocation for all devices included in wireless communication system 1000 .

Information necessary for time slot allocation is, for example, the following.
(1) Packet generation cycle, packet generation timing (2) Packet size (3) Permissible delay (4) ACK/NACK information (whether handshake communication exists)
(5) Traffic volume (6) Communication error information (communication error frequency, number of retransmissions, etc.)
(7) Transmission timing of traffic to be transmitted (8) Allowable delay amount of traffic to be transmitted (step S3):
In step S3, the counter value setting unit 15 of the coordinator device 100 performs wireless communication based on the wireless system information Info_sys output from the wireless system information acquisition/holding unit 13 and the data D_slot_def output from the time slot definition unit 14. Processing is performed to set a counter value Cnt(TrX) (TrX is a variable specifying traffic) for each traffic that the device is about to transmit. Specifically, the counter value setting unit 15 sets the counter value Cnt(TrX) based on the transmission timing of each traffic that the wireless communication device is trying to transmit and the allowable delay amount. The counter value setting unit 15 sets (specifies) the allowable delay amount of each traffic by the number of time slots. For example, when the transmission timing of traffic TrX is time tx, the allowable delay amount of traffic TrX (from time tx) is X1 [ms], and the time slot length defined by data D_slot_def is Tsl [ms] , the counter value setting unit 15 sets the allowable delay amount of the traffic Trx to
Cnt(TrX)=ceil(X1/Tsl)−1
ceil(): ceiling function, ceil(x)=n+1 when n<x≦n+1 (n: integer)
(identified by the number of timeslots). The counter value setting unit 15 sets the value acquired as described above to the counter value Cnt(TrX) of the traffic Trx.

Then, the counter value setting unit 15 outputs data including the transmission timing of each traffic and the counter value Cnt (TrX) to the traffic adjustment processing unit 16 as data D_cnt.

(Step S4):
In step S4, the traffic adjustment processing unit 16 of the coordinator device 100 identifies traffic to be transmitted in each time slot based on the transmission timing of each traffic that the wireless communication device is trying to transmit and the counter value Cnt(TrX). perform traffic conditioning operations to Here, the traffic adjustment processing when the traffic Tr1 to Tr4 are set as follows will be described with reference to FIGS. 7 to 11. FIG. 7 to 11 are diagrams for explaining the process of determining the time slots for transmitting the traffic Tr1 to Tr4 (the process of allocating time slots). It shows the case where . It is assumed that the time slot length is 20 ms. In FIGS. 7 to 11, each traffic is indicated by a rectangle, the allowable delay amount is expressed as Ta(TrX) (allowable delay amount of traffic TrX), and is indicated by an arrow above the rectangle indicating each traffic.
(1) Traffic Tr1:
Source: STA1-1
Transmission timing: time t0
Allowable delay: 40 ms (equivalent to 2 time slots)
Counter value: Cnt (Tr1)=1
(2) Traffic Tr2:
Source: STA1-2
Transmission timing: time t0
Allowable delay: 60 ms (equivalent to 3 time slots)
Counter value: Cnt (Tr2) = 2
(3) Traffic Tr3:
Source: AP1-1
Transmission timing: time t0
Allowable delay: 20 ms (equivalent to one time slot)
Counter value: Cnt (Tr3) = 0
(4) Traffic Tr4:
Source: AP1-1
Transmission timing: time t2
Allowable delay: 40 ms (equivalent to 2 time slots)
Counter value: Cnt (Tr4)=1
The traffic Tr1-Tr4 set as described above corresponds to the state shown in FIG. As shown in FIG. 7, in the first time slot (time slot from time t0 to t1), three traffic Tr1 to Tr3 are candidates for transmission, but the number N of traffic that can be transmitted in one time slot is "1", we need to decide which traffic should be sent in the first time slot.

Therefore, the traffic adjustment processing unit 16 performs processing as follows.
(1A) In the k-th (k: natural number) time slot, if the number of traffic that is a transmission candidate is equal to or less than the number of traffic that can be transmitted in one time slot N (in the case of FIG. 7, N=1), Traffic that is a candidate for transmission is determined as traffic to be transmitted in the k-th time slot.
(1B) In the k-th (k: natural number) time slot, if the number of traffic that is a transmission candidate is greater than the number of traffic that can be transmitted in one time slot N (in the case of FIG. 7, N=1), The traffic that is a transmission candidate is sorted by the counter value Cnt, N pieces of traffic with the smallest counter value are selected (N=1 in the case of FIG. 7), and the selected traffic is transmitted in the k-th time slot. Decide which traffic to use.
(2) For traffic that was a candidate for transmission in the k-th time slot and was not determined as traffic to be transmitted in the k-th time slot, traffic that is a candidate for transmission in the k+1-th time slot , and the counter value Cnt of the traffic concerned is changed to a value obtained by subtracting "1".

The traffic adjustment processing unit 16 repeatedly executes the processes (1A), (1B), and (2) above to determine the traffic to be transmitted in each time slot.

In the case of FIG. 7, in the first time slot, the three traffics Tr1 to Tr3 are candidates for transmission, which is greater than the number of traffic N (=1) that can be transmitted in one time slot. The traffic adjustment processing unit 16 sorts the traffic Tr1 to Tr3 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16 selects N (N=1) in descending order of the counter value. In the case of FIG. 7, the traffic adjustment processing unit 16 selects the traffic Tr3 (Cnt(Tr3)=0) with the smallest counter value, and transmits the traffic Tr3 (source: AP1-1) at the first time slot. The traffic to be transmitted is determined (process (1B)).

In addition, the traffic adjustment processing unit 16 regards the traffic Tr1 and Tr2, which were candidates for transmission in the first time slot and were not determined as traffic to be transmitted in the first time slot, in the second time slot. (time slots from time t1 to t2), and the counter value Cnt of the traffic Tr1 and Tr2 is changed to a value obtained by subtracting "1". That is, the traffic adjustment processing unit 16
Cnt(Tr1)=1-1=0
Cnt(Tr2)=2-1=1
(process (2)).

After the above processing, as shown in FIG. 8, the traffic adjustment processing unit 16 performs processing for determining traffic to be transmitted in the second time slot.

In other words, as shown in FIG. 8, in the second time slot, there are two traffics Tr1 and Tr2 that are candidates for transmission. is also large, the traffic adjustment processing unit 16 sorts the traffic Tr1 to Tr2 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16 selects N (N=1) in descending order of the counter value. In the case of FIG. 8, the traffic adjustment processing unit 16 selects the traffic Tr1 (Cnt(Tr1)=0) with the smallest counter value, and transmits the traffic Tr1 (source: STA1-1) in the second time slot. The traffic to be transmitted is determined (process (1B)).

In addition, the traffic adjustment processing unit 16 performs traffic Tr2, which is a candidate for transmission in the second time slot and has not been determined as traffic to be transmitted in the second time slot, at the third time slot. The traffic Tr2 is changed to a value obtained by subtracting "1" from the counter value Cnt of the traffic Tr2, which is regarded as a transmission candidate traffic in the slot (time slot from time t2 to t3). That is, the traffic adjustment processing unit 16
Cnt(Tr2)=1-1=0
(process (2)).

After the above processing, as shown in FIG. 9, the traffic adjustment processing unit 16 performs processing for determining traffic to be transmitted in the third time slot.

In other words, as shown in FIG. 9, in the third time slot, the two traffics Tr2 and Tr4 are candidates for transmission. is also large, the traffic adjustment processing unit 16 sorts the traffic Tr2 and Tr4 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16 selects N (N=1) in descending order of the counter value. In the case of FIG. 9, the traffic adjustment processing unit 16 selects traffic Tr2 (Cnt(Tr2)=0) with the smallest counter value, and transmits the traffic Tr2 (source: STA1-2) at the third time slot. The traffic to be transmitted is determined (process (1B)).

In addition, the traffic adjustment processing unit 16 performs traffic Tr4, which is a candidate for transmission in the third time slot and has not been determined as traffic to be transmitted in the third time slot, at the fourth time slot. The traffic Tr4 is changed to a value obtained by subtracting "1" from the counter value Cnt of the traffic Tr4, which is regarded as a transmission candidate traffic in the slot (time slot from time t3 to t4). That is, the traffic adjustment processing unit 16
Cnt(Tr4)=1-1=0
(process (2)).

After the above processing, as shown in FIG. 10, the traffic adjustment processing unit 16 performs processing for determining traffic to be transmitted in the fourth time slot.

That is, as shown in FIG. 10, in the fourth time slot, the traffic that is a candidate for transmission is one traffic Tr4, which is equal to or less than the number of traffic N (=1) that can be transmitted in one time slot. Therefore, traffic Tr4, which is a transmission candidate, is determined as traffic to be transmitted in the fourth time slot (process (1A)).

As described above, the traffic adjustment processing unit 16 performs traffic adjustment processing, thereby determining the traffic to be transmitted in the first to fourth time slots.

Then, the traffic adjustment processing unit 16 performs the same processing as above for the fifth and subsequent time slots, thereby specifying the traffic to be transmitted in each time slot. FIG. 11 shows a state (one example) in which traffic to be transmitted in each time slot is determined in the case of such processing. As can be seen from FIG. 11, by executing the traffic adjustment process as described above, all traffic is arranged to be transmitted at timings that are equal to or less than the allowable delay amount.

The traffic adjustment processing unit 16 converts data indicating the result of traffic adjustment processing (for example, data including information for determining which traffic is to be transmitted in which time slot as shown in FIG. 11) into data D_adj. Output to the slot allocation information generation unit 17 .

(Step S5):
In step S5, time slot allocation information generation processing is executed. That is, the time slot allocation information generation unit 17 of the coordinator device 100 performs wireless communication based on the wireless system information Info_sys output from the wireless system information acquisition/holding unit 13 and the data D_adj output from the traffic adjustment processing unit 16. Generate time slot assignment information for use in system 1000 .

The time slot allocation information generator 17 generates data D_slot in a data format composed of a first header H1 and a payload P1, as shown in FIG. 12, for example. That is, the first byte of data D_slot indicates the transmission interval of a series of time slots (240 ms in the case of FIG. 12), and the second byte of data D_slot indicates the number of time slots included in the transmission interval of the time slots ( In the case of FIG. 12, 12) are shown. From the 3rd byte, a node ID is indicated by 1 byte. All devices included in the wireless communication system 1000 have data of a correspondence table between connected devices and node IDs as shown in the right diagram of FIG. , devices assigned to a predetermined time slot (devices permitted to communicate in the predetermined time slot) can be specified.

The time slot allocation information generator 17 generates data D_slot in a data format as shown in FIG. 12, for example. The time slot allocation information generator 17 generates data D_slot based on the data D_adj (traffic adjustment processing result data) output from the traffic adjustment processor 16 . For example, data D_slot shown in FIG. 13 corresponds to result data D_adj of traffic adjustment processing determined by the state shown in FIG.

(Step S6):
In step S6, coordinator device 100 transfers (1) data D_slot_def including time slot definition information and (2) data D_slot including time slot allocation information generated in steps S1 to S5 to first access point AP1-1. , and the first access point AP1-1 receives the data transmitted from the coordinator device 100 (step S601).

The first access point AP1-1 stores the data D_slot_def and the data D_slot received from the coordinator device 100 in the time slot information storage unit 24, and performs RF processing on the wireless terminals STA1-1 and STA1-2. , through antenna Ant1.

The wireless terminal STA1-1 receives the data transmitted from the first access point AP1-1 and stores it in the time slot information storage unit 33 (step S602). The wireless terminal STA1-2 also performs the same processing as the wireless terminal STA1-1, and stores the data transmitted from the first access point AP1-1 (step S603).

The second access point AP2-1 and the wireless terminals STA2-1 and STA2-2 also perform the same processing as described above (steps S604 to S606).

Also, the third access point AP1-3 and the wireless terminals STA3-1 and STA3-2 perform the same processing as described above (steps S607 to S609).

In wireless communication system 1000, data D_slot (time slot allocation information) is periodically transmitted from coordinator apparatus 100 to each access point, and is periodically transmitted from each access point to the wireless system to which the access point belongs. It is transmitted to the wireless terminals, eg, by beacons.

As a result, all devices of the wireless communication system 1000 store and hold (1) data D_slot_def including time slot definition information and (2) data D_slot including time slot assignment information. Then, all the devices (wireless communication devices) of the wireless communication system 1000 each transmit traffic within the time slot indicated by the time slot assignment information according to the data D_slot including the time slot assignment information (for example, Transmit the traffic according to the data D_slot shown in FIG. 11). Thereby, in the wireless communication system 1000, each traffic is transmitted at appropriate timing.

As described above, in the wireless communication system 1000, by using time slots that are commonly defined based on information (information indicating communication status, information indicating communication performance, etc.) of all devices included in the wireless communication system 1000, , one channel can be used by multiple wireless systems in a time division manner. Further, in the wireless communication system 1000, as described above, the counter value considering the transmission timing and the allowable delay amount for the traffic to be transmitted by each communication device is represented by an integer value in units of the time slot length. set a counter value to be transmitted, and based on the counter value, identify the traffic to be transmitted in each time slot. That is, in the wireless communication system 1000, by introducing a counter value represented by an integer value in units of time slot length, the combinatorial optimization problem of at what timing each time slot should be transmitted can be easily solved. method. Then, in the wireless communication system 1000, traffic to be transmitted in each time slot is determined based on the solution thus obtained (solution of the combinatorial optimization problem). Therefore, the wireless communication system 1000 can appropriately control the traffic transmission timing even in a narrow space where many wireless communication devices exist. As a result, the wireless communication system 1000 can perform high-speed and highly accurate wireless communication without degrading wireless communication performance.

In the radio communication system 1000, in the above traffic adjustment processing, the initial value of the counter value of the traffic that each communication device is about to transmit is set to an integer value obtained by converting the allowable delay amount of the traffic into the time slot length. By doing so, it is possible to more appropriately control the transmission timing of traffic.

That is, in the wireless communication system 1000, the initial value of the counter value of the traffic that each communication device is about to transmit is set to the number of time slots corresponding to the allowable delay amount of the traffic, and the transmission timing desired by each communication device is set. In a time slot, it is assigned as transmission candidate traffic. Then, in the radio communication system 1000, (1) if the number of transmission candidate traffics in the relevant time slot is equal to or less than the number of traffics to be transmitted in one time slot, the transmission candidate traffic is determined as the traffic to be transmitted in the relevant time slot. , (2) If the number of traffic candidates for transmission in the relevant time slot is greater than the number of traffic to be transmitted in one time slot, sort by the counter value and select N (N: in one time slot) from the smallest counter value. number of traffic that can be transmitted) are selected, and the selected N traffics are determined as traffic to be transmitted in the relevant time slot.

Then, in the radio communication system 1000, traffic that is a candidate for transmission in a time slot but has not been determined as traffic to be transmitted in that time slot is treated as a candidate for transmission in the next time slot. , to a value obtained by subtracting "1" from the counter value Cnt of the traffic. As a result, when determining the traffic to be transmitted in a certain time slot, by checking the traffic counter value, it is possible to easily grasp by how many time slots the traffic can be shifted backward. . That is, in the wireless communication system 1000, the counter value is decremented by 1 every time the traffic that is a candidate for transmission in the time slot is shifted backward. It can be easily grasped that it can be shifted backward only one time. For example, for traffic whose transmission timing is the start time of the k-th time slot and whose initial value of the counter value (value corresponding to the allowable delay amount) is C0, by the above processing, if the traffic is shifted backward n times (When it is out of the transmission candidates n times), the counter value of the traffic is C0-n. can be used as a transmission candidate for the time slot after only one time), and if it is "0", it is understood that it cannot be shifted any further (if it is shifted any further, the allowable delay amount will be exceeded). can do.

Thus, in the wireless communication system 1000, by introducing a counter value represented by an integer value in units of time slot length and processing as described above, it is preferable to transmit each time slot at which timing. The combinatorial optimization problem of whether or not can be solved by a simple method. Therefore, in the radio communication system 1000, even if there are many radio communication devices included in the radio communication system 1000, it is possible to appropriately determine the traffic transmission timing of each radio communication device.

[Second embodiment]
Next, a second embodiment will be described. Parts similar to those of the above-described embodiment are given the same reference numerals, and detailed description thereof is omitted.

FIG. 14 is a schematic configuration diagram of a wireless communication system 2000 according to the second embodiment.

FIG. 15 is a schematic configuration diagram of a coordinator device 100A according to the second embodiment.

FIG. 16 is a diagram showing the data structure of data D_slot used in the wireless communication system 2000 of the second embodiment.

<2.1: Configuration of wireless communication system>
As shown in FIG. 14, the wireless communication system 2000 of the second embodiment has a configuration in which the coordinator device 100 in the wireless communication system 1000 of the first embodiment is replaced with a coordinator device 100A. 15, the coordinator device 100A of the second embodiment has a configuration in which the traffic adjustment processing unit 16 in the coordinator device 100 of the first embodiment is replaced with a traffic adjustment processing unit 16A. . Otherwise, wireless communication system 2000 is similar to wireless communication system 1000 .

The traffic adjustment processing unit 16A performs processing for selecting which traffic in one time slot when the traffic of transmission candidates cannot be identified only from the result of sorting the counter values. In this respect, the traffic adjustment processor 16A differs from the traffic adjustment processor 16 of the first embodiment. The traffic adjustment processing unit 16A can store and hold data regarding the allowable delay amount of each traffic, and also receives a control signal Ctl_pri for adjusting the priority label.

<2.2: Operation of wireless communication system>
The operation of the radio communication system 2000 configured as above will be described below with reference to the drawings.

For convenience of explanation, a case (one example) in which the upper limit value of the number of traffics transmitted in one time slot in the wireless communication system 2000 is "2" (N=2) will be explained below. Note that the upper limit value N of the number of traffic transmitted in one time slot may be a value other than "2".

Radio communication system 2000 uses data D_slot in the format shown in FIG. As shown in FIG. 16, data D_slot used in this embodiment has a data format obtained by adding a second header H2 to the data format shown in FIGS. The radio communication system 2000 differs from the radio communication system 1000 of the first embodiment in that data D_slot having a data format with a second header H2 added is used.

Then, as shown in FIG. 16, in the second header H2,
(1) Nth slot (1 byte)
(2) Number of nodes (1 byte)
(3) Node ID (bytes for the number of nodes)
can include one or more pieces of data in units of

For example, in the second header H2 shown in FIG. 16,
(1) in the first slot, a device with a node ID of "4" and a device with a node ID of "6" can communicate using a channel used by the wireless communication system;
(2) in the second slot, the device with the node ID of "3" and the device with the node ID of "1" can communicate using the channel used by the wireless communication system;
(3) in the sixth slot, the device with the node ID of "2" and the device with the node ID of "9" can communicate using the channel used by the wireless communication system;
(4) In the eighth slot, it means that the device with the node ID of "1" and the device with the node ID of "3" can communicate using the channel used by the wireless communication system.

In the wireless communication system 2000, by using the data D_slot having the data format defined above, multiple wireless communication devices can communicate using the same channel in one time slot. In the above description, only the case where the number of devices assigned to one time slot is "2" is exemplified. Data may be set in the second header H2 so that the H2 can communicate with the H2.

In radio communication system 2000, coordinator apparatus 100A obtains and holds information necessary for time slot allocation for all devices included in radio communication system 2000. FIG.

Information necessary for time slot allocation is, for example, the following.
(1) Packet generation cycle, packet generation timing (2) Packet size (3) Permissible delay (4) ACK/NACK information (whether handshake communication exists)
(5) Traffic volume (6) Communication error information (communication error frequency, number of retransmissions, etc.)
(7) Transmission timing of traffic to be transmitted (8) Allowable delay amount of traffic to be transmitted (9) Priority label In the second embodiment, from the case of the first embodiment, "(9) Priority Label” is acquired as information necessary for time slot allocation.

The coordinator device 100A acquires the wireless system information Info_sys by collecting the above information from each wireless communication device.

In the wireless communication system 2000 of the second embodiment, the traffic adjustment process (process of step S4), the time slot allocation information generation process (process of step S5), and the transmission process (process of step S6) are performed in the first embodiment. Since the other processes are the same as those in the first embodiment, the above three processes will be described below.

In the following, the case where traffic is selected based on (1) counter value and allowable delay amount and (2) traffic selection based on counter value, allowable delay amount and priority label will be explained separately. do.

(2.2.1: When selecting traffic based on counter value and allowable delay amount)
First, (1) the case of selecting traffic based on the counter value and the allowable delay amount will be described.

(Step S4):
In step S4, the traffic adjustment processing unit 16A of the coordinator device 100A identifies traffic to be transmitted in each time slot based on the transmission timing of each traffic that the wireless communication device is trying to transmit and the counter value Cnt(TrX). perform traffic conditioning operations to Here, the traffic adjustment processing when the traffic Tr1 to Tr5 are set as follows will be described with reference to FIGS. 17 to 20. FIG. 17 to 20 are diagrams for explaining the process of determining the time slots for transmitting the traffic Tr1 to Tr5 (the process of allocating time slots). It shows the case where . It is assumed that the time slot length is 20 ms. 17 to 20, each traffic is indicated by a rectangle, the allowable delay amount is expressed as Ta (TrX) (allowable delay amount of traffic TrX), and is indicated by an arrow above the rectangle indicating each traffic.
(1) Traffic Tr1:
Source: STA1-1
Transmission timing: time ta (time one time slot before time t0)
Allowable delay: 80 ms (equivalent to 4 time slots)
Counter value: Cnt (Tr1)=2
(2) Traffic Tr2:
Source: STA1-2
Transmission timing: time t0
Allowable delay: 60 ms (equivalent to 3 time slots)
Counter value: Cnt (Tr2) = 2
(3) Traffic Tr3:
Source: AP1-1
Transmission timing: time t0
Allowable delay: 20 ms (equivalent to one time slot)
Counter value: Cnt (Tr3) = 0
(4) Traffic Tr4:
Source: STA2-1
Transmission timing: time t0
Allowable delay: 20 ms (equivalent to one time slot)
Counter value: Cnt (Tr4) = 0
(5) Traffic Tr5:
Source: STA2-2
Transmission timing: time t0
Allowable delay: 20 ms (equivalent to one time slot)
Counter value: Cnt (Tr5) = 0
The traffic Tr1-Tr5 set as described above corresponds to the state shown in FIG. As shown in FIG. 17, five traffic Tr1 to Tr5 are candidates for transmission in the first time slot (time slot from time t0 to t1), but the number of traffic N that can be transmitted in one time slot is "2", it is necessary to decide which traffic should be sent in the first time slot.

Therefore, the traffic adjustment processing unit 16A performs processing as follows.
(1A) In the k-th (k: natural number) time slot, if the number of traffic that is a transmission candidate is equal to or less than the number of traffic N (in the case of FIG. 17, N=2) that can be transmitted in one time slot, Traffic that is a candidate for transmission is determined as traffic to be transmitted in the k-th time slot.
(1B) In the k-th (k: natural number) time slot, if the number of traffic that is a transmission candidate is greater than the number of traffic that can be transmitted in one time slot N (in the case of FIG. 17, N=2), The transmission candidate traffic is sorted by the counter value Cnt.
(1B-1) If it is possible to select N pieces of traffic (N=2 in the case of FIG. 17) from the smallest counter value, the N pieces of traffic are determined as traffic to be transmitted in the k-th time slot.
(1B-2) If N (N=2 in the case of FIG. 17) cannot be selected from the smallest counter value, determination is made based on the allowable delay amount of traffic. That is, the traffic to be selected is sorted according to the allowable delay amount, and the traffic is selected in ascending order of the allowable delay amount so that the number of traffic to be selected is N. Then, the selected traffic is determined as traffic to be transmitted in the k-th time slot.
(2) For traffic that was a candidate for transmission in the k-th time slot and was not determined as traffic to be transmitted in the k-th time slot, traffic that is a candidate for transmission in the k+1-th time slot , and the counter value Cnt of the traffic concerned is changed to a value obtained by subtracting "1".

The traffic adjustment processing unit 16A repeats the processes (1A), (1B), (1B-1), (1B-2), and (2) above to determine the traffic to be transmitted in each time slot.

In the case of FIG. 17, in the first time slot, five traffics Tr1 to Tr5 are candidates for transmission, which is larger than the number of traffic N (=2) that can be transmitted in one time slot. The traffic adjustment processing unit 16A sorts the traffic Tr1 to Tr5 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16 selects N (N=2) in descending order of the counter value. In the case of FIG. 17, the traffic adjustment processing unit 16A selects the traffic Tr4 (Cnt(Tr4)=0) and the traffic Tr5 (Cnt(Tr5)=0) having the same value and the smallest counter value, and selects the traffic Tr4 (transmission Source: STA2-1) and traffic Tr5 (source: STA2-2) are determined as traffic to be transmitted in the first time slot (processing (1B)).

In addition, the traffic adjustment processing unit 16A selects the traffic Tr1 to Tr3, which are candidates for transmission in the first time slot and have not been determined as traffic to be transmitted in the first time slot, in the second time slot. (time slots of times t1 to t2), and the counter value Cnt of the traffic Tr1 to Tr3 is changed to a value obtained by subtracting "1". That is, the traffic adjustment processing unit 16
Cnt(Tr1)=2-1=1
Cnt(Tr2)=2-1=1
Cnt(Tr3)=1-1=0
(process (2)).

After the above processing, as shown in FIG. 18, the traffic adjustment processing unit 16A performs processing for determining traffic to be transmitted in the second time slot.

In other words, as shown in FIG. 18, in the second time slot, there are three traffics Tr1 to Tr3 that are candidates for transmission. is also large, the traffic adjustment processing unit 16A sorts the traffic Tr1 to Tr3 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16A determines whether or not N (N=2) can be selected in descending order of the counter value. In the case of FIG. 18, the minimum counter value is Cnt(Tr3) of traffic Tr3=0, but the next smallest counter values are Cnt(Tr1) and Cnt(Tr2). Since it is "1", it is not possible to identify the N (N=2) traffic with the smallest counter value to be selected.

Therefore, the traffic adjustment processing unit 16A determines based on the allowable delay amount of traffic. In other words, the traffic adjustment processing unit 16A sorts the traffic to be selected according to the allowable delay amount, and selects the traffic in descending order of the allowable delay amount so that the number of selected traffic is N. do. In the case of FIG. 18, the allowable delay amount Ta (Tr1) for traffic Tr1 is 80 ms for "4" time slots, the allowable delay amount Ta (Tr2) for traffic Tr2 is 60 ms for "3" time slots, and Ta Since (Tr1)>Ta(Tr2), traffic Tr2 with a smaller allowable delay amount is determined as traffic to be transmitted in the second time slot (process (1B-2)).

That is, in the case of FIG. 18, the traffic adjustment processing unit 16A determines traffic Tr3 and traffic Tr2 as the traffic to be transmitted in the second time slot by the above process.

In addition, the traffic adjustment processing unit 16A processes the traffic Tr1, which is a candidate for transmission in the second time slot and has not been determined as traffic to be transmitted in the second time slot, at the third time slot. The traffic Tr1 is changed to a value obtained by subtracting "1" from the counter value Cnt of the traffic Tr1, which is regarded as a transmission candidate traffic in the slot (time slot from time t2 to t3). That is, the traffic adjustment processing unit 16A
Cnt(Tr1)=1-1=0
(process (2)).

After the above processing, as shown in FIG. 19, the traffic adjustment processing unit 16A performs processing for determining traffic to be transmitted in the third time slot.

That is, as shown in FIG. 19, in the third time slot, the traffic that is a candidate for transmission is one traffic Tr1, which is equal to or less than the number of traffic N (=2) that can be transmitted in one time slot. Therefore, traffic Tr1, which is a transmission candidate, is determined as traffic to be transmitted in the third time slot (process (1A)).

In this manner, the traffic adjustment processing unit 16A performs traffic adjustment processing, thereby determining the traffic to be transmitted in the first to third time slots.

Then, the traffic adjustment processing unit 16A can specify the traffic to be transmitted in each time slot by performing the same processing as described above for the fourth and subsequent time slots. FIG. 20 shows a state (an example) in which traffic to be transmitted in each time slot is determined in the case of such processing. As can be seen from FIG. 20, when the traffic adjustment process is executed as described above, the number of traffic transmitted in one time slot is 2 or less, and the timing at which all traffic is equal to or less than the allowable delay amount. is arranged to be sent by

The traffic adjustment processing unit 16A converts data indicating the result of traffic adjustment processing (for example, data including information for determining which traffic is to be transmitted in which time slot as shown in FIG. 11) into data D_adj. Output to the slot allocation information generation unit 17 .

(Step S5):
In step S5, time slot allocation information generation processing is executed. That is, the time slot allocation information generation unit 17 of the coordinator device 100A performs wireless communication based on the wireless system information Info_sys output from the wireless system information acquisition/holding unit 13 and the data D_adj output from the traffic adjustment processing unit 16. Generate time slot assignment information for use in system 1000 .

The time slot allocation information generator 17 generates data D_slot in a data format as shown in FIG. 16, for example. The time slot allocation information generator 17 generates data D_slot based on the data D_adj (traffic adjustment processing result data) output from the traffic adjustment processor 16A. For example, data D_slot shown in FIG. 16 corresponds to result data D_adj of traffic adjustment processing determined by the state shown in FIG.

(Step S6):
In step S6, the coordinator device 100A transfers (1) data D_slot_def including time slot definition information and (2) data D_slot including time slot allocation information generated in steps S1 to S5 to the first access point AP1-1. , and the first access point AP1-1 receives the data transmitted from the coordinator device 100 (step S601).

The first access point AP1-1 stores the data D_slot_def and the data D_slot received from the coordinator device 100 in the time slot information storage unit 24, and performs RF processing on the wireless terminals STA1-1 and STA1-2. , through antenna Ant1.

The wireless terminal STA1-1 receives the data transmitted from the first access point AP1-1 and stores it in the time slot information storage unit 33 (step S602). The wireless terminal STA1-2 also performs the same processing as the wireless terminal STA1-1, and stores the data transmitted from the first access point AP1-1 (step S603).

The second access point AP2-1 and the wireless terminals STA2-1 and STA2-2 also perform the same processing as described above (steps S604 to S606).

Also, the third access point AP1-3 and the wireless terminals STA3-1 and STA3-2 perform the same processing as described above (steps S607 to S609).

In wireless communication system 1000, data D_slot (time slot allocation information) is periodically transmitted from coordinator apparatus 100 to each access point, and is periodically transmitted from each access point to the wireless system to which the access point belongs. It is transmitted to the wireless terminals, eg, by beacons.

As a result, all devices of the wireless communication system 2000 store and hold (1) data D_slot_def including time slot definition information and (2) data D_slot including time slot allocation information. Then, all the devices (wireless communication devices) of the wireless communication system 2000 each transmit traffic within the time slot indicated by the time slot assignment information according to the data D_slot including the time slot assignment information (for example, Transmit the traffic according to the data D_slot shown in FIG. 20). Thereby, in the wireless communication system 2000, each traffic is transmitted at appropriate timing.

(2.2.2: When selecting traffic based on counter value, allowable delay amount, priority label)
Next, (2) the case where traffic selection is performed based on the counter value, the allowable delay amount, and the priority label will be described.

(Step S4):
In step S4, the traffic adjustment processing unit 16A of the coordinator device 100A identifies traffic to be transmitted in each time slot based on the transmission timing of each traffic that the wireless communication device is trying to transmit and the counter value Cnt(TrX). perform traffic conditioning operations to Here, the traffic adjustment processing when the traffic Tr1 to Tr5 are set as follows will be described with reference to FIGS. 21 to 23. FIG. 21 to 23 are diagrams for explaining the process of determining the time slots for transmitting the traffic Tr1 to Tr5 (the process of allocating time slots). It shows the case where . It is assumed that the time slot length is 20 ms. 21 to 23, each traffic is indicated by a rectangle, the allowable delay amount is expressed as Ta (TrX) (allowable delay amount of traffic TrX), and is indicated by an arrow above the rectangle indicating each traffic.
(1) Traffic Tr1:
Source: STA3-1
Transmission timing: time t0
Allowable delay: 80 ms (equivalent to 4 time slots)
Counter value: Cnt (Tr1)=3
Priority label: PriL=0
(2) Traffic Tr2:
Source: STA1-2
Transmission timing: time t0
Allowable delay: 60 ms (equivalent to 3 time slots)
Counter value: Cnt (Tr2) = 2
Priority label: PriL=5
(3) Traffic Tr3:
Source: AP1-1
Transmission timing: time t0
Allowable delay: 40 ms (equivalent to 2 time slots)
Counter value: Cnt (Tr3)=1
Priority label: PriL=4
(4) Traffic Tr4:
Source: STA2-1
Transmission timing: time t0
Allowable delay: 40 ms (equivalent to 2 time slots)
Counter value: Cnt (Tr4)=1
Priority label: PriL=3
(5) Traffic Tr5:
Source: STA2-2
Transmission timing: time t0
Allowable delay: 20 ms (equivalent to one time slot)
Counter value: Cnt (Tr5) = 0
The traffic Tr1 to Tr5 set as described above corresponds to the state shown in FIG. As shown in FIG. 21, five traffic Tr1 to Tr5 are candidates for transmission in the first time slot (time slot from time t0 to t1), but the number N of traffic that can be transmitted in one time slot is "2", it is necessary to decide which traffic should be sent in the first time slot.

Therefore, the traffic adjustment processing unit 16A performs processing as follows.
(1A) In the k-th (k: natural number) time slot, if the number of traffic that is a transmission candidate is equal to or less than the number of traffic that can be transmitted in one time slot N (in the case of FIG. 21, N=2), Traffic that is a candidate for transmission is determined as traffic to be transmitted in the k-th time slot.
(1B) In the k-th (k: natural number) time slot, if the number of traffic that is a transmission candidate is greater than the number of traffic that can be transmitted in one time slot N (in the case of FIG. 21, N=2), The transmission candidate traffic is sorted by the counter value Cnt.
(1B-1) If N traffic (N=2 in the case of FIG. 21) can be selected from the one with the smallest counter value, the N traffic is determined as the traffic to be transmitted in the k-th time slot.
(1B-2) If N (N=2 in the case of FIG. 21) cannot be selected from the smallest counter value, determination is made based on the allowable delay amount of traffic. That is, the traffic to be selected is sorted by the allowable delay amount.
(1B-2-1) From the result of sorting the allowable delay amounts, if a total of N (N=2 in the case of FIG. 21) traffic to be transmitted in the k-th time slot can be selected, the order with the smallest allowable delay amount is selected. Select the traffic in order to determine a total of N traffics to be transmitted in the kth time slot.
(1B-2-2) If a total of N (N=2 in the case of FIG. 21) traffic to be transmitted in one time slot cannot be selected from the sorted result of the allowable delay amount, the traffic priority label PriL is used for determination. . In other words, the traffic to be selected is sorted by the priority label PriL, and the traffic is selected in descending order of the priority label so that the number of traffic to be selected is N. Then, the selected traffic is determined as traffic to be transmitted in the k-th time slot.

It is assumed that the larger the value of the priority label, the higher the priority of traffic transmission (the traffic that must be transmitted with priority).
(2) For traffic that was a candidate for transmission in the k-th time slot and was not determined as traffic to be transmitted in the k-th time slot, traffic that is a candidate for transmission in the k+1-th time slot , and the counter value Cnt of the traffic concerned is changed to a value obtained by subtracting "1".

The traffic adjustment processing unit 16A processes (1A), (1B), (1B-1), (1B-2), (1B-2-1), (1B-2-2), and (2) above. repeatedly to determine the traffic to send in each timeslot.

In the case of FIG. 21, in the first time slot, five traffics, Tr1 to Tr5, are candidates for transmission. The traffic adjustment processing unit 16A sorts the traffic Tr1 to Tr5 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16A selects N (N=2) from the smaller counter value. In the case of FIG. 21, the counter values of the four traffics Tr2 to Tr5 are "1" (Cnt(Tr2)=Cnt(Tr3)=Cnt(Tr4)=Cnt(Tr5)=1), and the same value is the minimum value. There are 4 traffics of . That is, in this case, N traffics cannot be selected from the result of sorting the counter values. Therefore, the traffic adjustment processing unit 16A sorts according to the allowable delay amount (processing (1B-2)).

As a result of the sorting, as can be seen from FIG.
Ta(Tr2)=Ta(Tr3)=Ta(Tr4)=Ta(Tr5)=40ms
, and N traffics cannot be selected even by sorting results based on the allowable delay amount.

Therefore, the traffic adjustment processing unit 16A sorts by the priority label PriL (processing (1B-2-2)).

As a result of the sorting, as can be seen from FIG.
PriL (Tr2) > PriL (Tr3) > PriL (Tr4) > PriL (Tr5)
Therefore, the traffic adjustment processing unit 16A determines traffic Tr2 and traffic Tr3, which are two traffics with the highest priority label values, as traffic to be transmitted in the first time slot (processing (1B- 2-2)).

In addition, the traffic adjustment processing unit 16A, regarding the traffic Tr1, Tr4, and Tr5, which were candidates for transmission in the first time slot and were not determined as traffic to be transmitted in the first time slot, The counter value Cnt of the traffic Tr1, Tr4, and Tr5 is changed to a value obtained by subtracting "1" from the traffic that is a candidate for transmission in the second time slot (time slot from time t1 to time t2). That is, the traffic adjustment processing unit 16
Cnt(Tr1)=3-1=2
Cnt(Tr4)=1-1=0
Cnt(Tr5)=1-1=0
(process (2)).

After the above processing, as shown in FIG. 22, the traffic adjustment processing unit 16A performs processing for determining traffic to be transmitted in the second time slot.

That is, as shown in FIG. 22, in the second time slot, there are three traffics Tr1, Tr3, and Tr4 that are candidates for transmission, and the number of traffic that can be transmitted in one time slot is N (=2 ), the traffic adjustment processing unit 16A sorts the traffic Tr1, Tr3, and Tr4 by the counter value Cnt (processing (1B)).

Then, the traffic adjustment processing unit 16A determines whether or not N (N=2) can be selected in descending order of the counter value. In the case of FIG. 22, the traffic Tr4 and the traffic Tr5 are the N (N=2) pieces of traffic with the smallest counter value, so the traffic adjustment processing unit 16A adjusts the traffic Tr4 and the traffic Tr5 at the second time. The traffic to be transmitted in the slot is determined (process (1A)).

In addition, the traffic adjustment processing unit 16A processes the traffic Tr1, which is a candidate for transmission in the second time slot and has not been determined as traffic to be transmitted in the second time slot, at the third time slot. The traffic Tr1 is changed to a value obtained by subtracting "1" from the counter value Cnt of the traffic Tr1, which is regarded as a transmission candidate traffic in the slot (time slot from time t2 to t3). That is, the traffic adjustment processing unit 16A
Cnt(Tr1)=2-1=1
(process (2)).

After the above processing, as shown in FIG. 23, the traffic adjustment processing unit 16A performs processing for determining traffic to be transmitted in the third time slot.

In other words, as shown in FIG. 23, in the third time slot, traffic that is a candidate for transmission is one traffic Tr1, which is equal to or less than the number of traffic N (=2) that can be transmitted in one time slot. Therefore, traffic Tr1, which is a transmission candidate, is determined as traffic to be transmitted in the third time slot (process (1A)).

In this manner, the traffic adjustment processing unit 16A performs traffic adjustment processing, thereby determining the traffic to be transmitted in the first to third time slots.

Then, the traffic adjustment processing unit 16A can specify the traffic to be transmitted in each time slot by performing the same processing as described above for the fourth and subsequent time slots.

In the wireless communication system 2000, by executing the traffic adjustment process as described above, the number of traffic transmitted in one time slot is N or less, and at the timing when all the traffic is equal to or less than the allowable delay amount. Can be arranged to be sent.

After the above processing, the wireless communication system 2000 executes the processing of steps S5 and S6 in the same manner as described above.

As described above, the wireless communication system 2000 can appropriately determine the traffic to be transmitted in one time slot by performing the processing as described above. That is, in the wireless communication system 2000, when the number of traffic candidates in one time slot is greater than the upper limit N of the number of traffic that can be transmitted in one time slot,
(1) select traffic to be transmitted in one time slot based on the results sorted by the count value;
(2) if it is not possible to determine N traffic to be transmitted in one time slot according to the result of sorting the count values, further select traffic to be transmitted in one time slot based on the result of sorting according to the allowable delay amount;
(3) If the N traffic to be transmitted in one time slot cannot be determined even by the sorting result of the allowable delay amount, the traffic to be transmitted in one time slot is further selected based on the result of sorting by priority label. do.

Therefore, in the wireless communication system 2000, even if the number of candidate traffics in one time slot is greater than the upper limit N of the number of traffic that can be transmitted in one time slot, transmission is performed in one time slot. It is possible to appropriately select (determine) the traffic to be sent.

Note that if N traffic to be transmitted in one time slot cannot be determined even by the result of sorting by priority label, the radio communication system 2000 further uses another priority label or another criterion (for example, the number of transmission data (Reference data for preferentially selecting a packet (traffic) with a large value) may be used to select (specify) traffic to be transmitted in one time slot.

Also, in the above, the case where the upper limit value N of the number of traffic that can be transmitted in one time slot is "2" has been described, but the present invention is not limited to this, and N may be another number. .

For example, FIG. 24 shows a diagram for explaining traffic selection processing (traffic adjustment processing) when the upper limit value N of the number of traffic that can be transmitted in one time slot is "4".

As shown in FIG. 24, even when N=4 and the number of candidate traffics in one time slot is greater than the upper limit N of the number of traffics that can be transmitted in one time slot, In the traffic adjustment processing unit 16A of the wireless communication system 2000,
(1) sorting by count value (Cnt);
(2) sorting by allowable delay amount;
(3) sorting by priority label;
, it is possible to properly select (specify) traffic to be transmitted in one time slot.

Also, in the wireless communication system 2000, the priority label PriL of each traffic may be changed by the control signal Ctl_pri input to the traffic adjustment processor 16A. For example, when the wireless communication system 2000 is installed in a factory, the priority label PriL of each traffic may be changed by the control signal Ctl_pri according to the operational status of the factory. For example, in a factory, during times when machine tools and robots are in operation, the control signal Ctl_pri is set so that high-priority communications necessary for operating the machine tools and robots are preferentially secured. By controlling the priority of the communication traffic to a high value, and during the time when the machine tools and robots are not in operation, the priority of the communication traffic for operating the machine tools and robots is lowered. It may be controlled to be a value. In other words, when the wireless communication system 2000 is installed in an environment where important communications change depending on the time zone, the priority label of the traffic of the important communication in the wireless communication system 2000 will be a high value depending on the time zone. You may make it control so that it may become. By doing so, the wireless communication system 2000 can control the transmission timing of traffic so that important communications can be reliably performed in a specific time period.

Note that the control signal Ctl_prj may be automatically generated based on predetermined data by a control unit (not shown) of the coordinator device 100A, or may be an interface (not shown) with the outside of the coordinator device 100A. ), and predetermined data (for example, data instructing to change the priority label) may be input and generated based on the data.

[Other embodiments]
In the above embodiment, the case where each wireless system has one access point has been described, but the present invention is not limited to this, and each wireless system may have a plurality of access points.

Also, the communication method used in the wireless communication system described in the above embodiments (including modifications) is included in the present invention.

Further, in the above embodiment, the case where the upper limit value N of the number of traffic transmitted in one time slot is a fixed value has been described, but the present invention is not limited to this. You may change the upper limit N of a number. In this case, for example, the traffic adjustment processing unit can be manually or automatically input with the upper limit value N of the number of traffic to be transmitted, and the traffic adjustment processing unit, in accordance with the input value N, in one time slot An upper limit value N of the number of traffic to be transmitted may be set. This makes it possible to vary the upper limit value N of the number of traffic transmitted in one time slot.

Also, in a wireless communication system, the wireless communication performance is measured when the upper limit value N of the number of traffic to be transmitted in one time slot is set to a predetermined value, and the wireless communication performance is improved according to the measurement result. , the value N may be changed.

Further, in the wireless communication system described in the above embodiments (including modifications), each block may be individually integrated into one chip by a semiconductor device such as an LSI, or may be integrated into one chip so as to include part or all of the block. may be changed.

Although LSI is used here, it may also be called IC, system LSI, super LSI, or ultra LSI depending on the degree of integration.

Further, the method of circuit integration is not limited to LSI, and may be implemented by a dedicated circuit or a general-purpose processor. An FPGA (Field Programmable Gate Array) that can be programmed after the LSI is manufactured, or a reconfigurable processor that can reconfigure the connections and settings of the circuit cells inside the LSI may be used.

Also, part or all of the processing of each functional block in each of the above embodiments may be implemented by a program. Part or all of the processing of each functional block in each of the above embodiments is performed by a central processing unit (CPU) in a computer. A program for performing each process is stored in a storage device such as a hard disk or ROM, and is read from the ROM or RAM and executed.

Further, each process of the above embodiments may be realized by hardware, or may be realized by software (including cases where it is realized together with an OS (operating system), middleware, or a predetermined library). Furthermore, it may be realized by mixed processing of software and hardware.

Further, for example, when the functional units of the above embodiments (including modifications) are implemented by software, the hardware configuration shown in FIG. Each functional unit may be realized by software processing using a hardware configuration connected by a Bus.

Also, the execution order of the processing methods in the above embodiments is not necessarily limited to the description of the above embodiments, and the execution order can be changed without departing from the gist of the invention.

A computer program that causes a computer to execute the method described above and a computer-readable recording medium that records the program are included in the scope of the present invention. Examples of computer-readable recording media include flexible disks, hard disks, CD-ROMs, MOs, DVDs, DVD-ROMs, DVD-RAMs, large-capacity DVDs, next-generation DVDs, and semiconductor memories. .

The computer program is not limited to being recorded on the recording medium, and may be transmitted via an electric communication line, a wireless or wired communication line, a network represented by the Internet, or the like.

The specific configuration of the present invention is not limited to the above-described embodiment, and various changes and modifications are possible without departing from the gist of the invention.

1000, 2000 Wireless communication system 100, 100A Coordinator device SYS1 First wireless system SYS2 Second wireless system SYS3 Third wireless system AP1-1 First access point AP2-1 Second access point AP3-1 Third access point STA1-1 , STA1-2, STA2-1, STA2-2, STA3-1, STA3-2 Wireless terminal 11 First communication interface 12 First communication processing unit 13 Wireless system information acquisition/holding unit 14 Time slot definition unit 15 Counter value setting unit 16, 16A traffic adjustment processing unit 17 time slot allocation information generation unit

Claims (11)

A wireless system each including one or more wireless communication devices, and a wireless communication method used in a wireless communication system including a plurality of the wireless systems,
a time slot defining step of defining a time slot for common use among the plurality of wireless systems, the time slot defining step of determining a slot length and a slot start time of the time slot;
a data collection step of collecting traffic data from the wireless communication device, which is data relating to transmission timing of traffic that the wireless communication device is trying to transmit and data relating to an allowable delay;
Based on the traffic data, for each traffic that the wireless communication device is trying to transmit, a counter value defined by the number of time slots, the counter value represented by an integer value in units of time slot length. a counter value setting step of setting the counter value based on the data on the allowable delay included in the traffic data for each traffic that the wireless communication device is about to transmit; ,
a traffic number setting step of setting the same time slot transmission traffic number, which is the number of traffic transmitted in one time slot;
a determination step of determining whether or not the number of traffic candidates for transmission in one time slot is equal to or less than the same time slot transmission traffic number;
(1) When it is determined in the determination step that the number of traffic candidates for transmission in one time slot is equal to or less than the number of traffic for transmission in the same time slot, all of the traffic candidates for transmission (2) the determination step determines that the number of traffic candidates for transmission in one time slot is not equal to or less than the same time slot transmission traffic number; If it is determined, in one time slot, a counter value sorting process, which is a sorting process for the counter values of the traffic that are candidates for transmission, is performed, and based on the result of the counter value sorting process, the same time a traffic adjustment step of selecting a number of traffic that matches the number of slot transmission traffic and determining the selected traffic as traffic to be transmitted in one time slot;
Communication-related information of at least one of the wireless system and the wireless communication device, comprising: (1) packet generation cycle and/or packet generation timing, (2) packet size and/or traffic volume, and (3) allowable delay amount and the information about the traffic to be transmitted in one time slot, which is determined by the traffic adjustment step, to each of the wireless communication devices included in the plurality of wireless systems. a time slot allocation information generation step for generating time slot allocation information, which is time slot information;
During a period specified by the time slots assigned by the time slot assignment information, the wireless communication device assigned by the time slot assignment information uses the channel used in the wireless communication system, a wireless communication step of performing wireless communication by transmitting traffic determined as traffic to be transmitted in one time slot by the traffic adjustment step;
A wireless communication method comprising: The counter value setting step includes:
setting the initial value of the counter value based on the number of time slots corresponding to the allowable delay amount of traffic to be transmitted by the wireless communication device;
The wireless communication method according to claim 1. The traffic conditioning step includes:
Update the counter value of traffic that is a candidate for traffic to be transmitted in one time slot and has not been selected as traffic to be transmitted in that time slot to a value obtained by subtracting 1;
The wireless communication method according to claim 1 or 2. When it is determined by the determining step that the number of traffic candidates for transmission in one time slot is not equal to or less than the same time slot transmission traffic number,
The traffic conditioning step includes:
In one time slot, the permissible delay amount of the traffic that is a candidate for transmission is sorted, and based on the result of the sorting process of the permissible delay amount and the result of the counter value sorting process , determine the traffic to be transmitted in one timeslot;
The wireless communication method according to any one of claims 1 to 3 . When it is determined by the determining step that the number of traffic candidates for transmission in one time slot is not equal to or less than the same time slot transmission traffic number,
The traffic conditioning step includes:
In one time slot, sorting is performed on priority labels indicating the communication priority of the traffic that is a candidate for transmission, and the results of the sorting of the priority labels and the counter value sorting are performed. determine the traffic to be transmitted in one timeslot based on the results of
The wireless communication method according to any one of claims 1 to 4 . further comprising an input step of inputting data for setting the value of the priority label;
the value of the priority label is set based on the data input by the input step;
The wireless communication method according to claim 5 . The value of the priority label is set to have a higher priority value for traffic with a larger number of transmission data,
The wireless communication method according to claim 5 or 6 . The traffic count setting step includes:
setting the same time slot transmission traffic number, which is the number of traffic to be transmitted in one time slot, to a fixed value;
The wireless communication method according to any one of claims 1 to 7 . The traffic count setting step includes:
setting the same time slot transmission traffic number, which is the number of traffic to be transmitted in one time slot, to a different value between time slots;
The wireless communication method according to any one of claims 1 to 7 . A program for causing a computer to execute the wireless communication method according to any one of claims 1 to 9 . A radio system each including one or a plurality of radio communication devices, a coordinator device used in a radio communication system including a plurality of the radio systems,
a time slot definition unit that defines a time slot for common use among the plurality of wireless systems, the time slot definition unit that determines a slot length and a slot start time of the time slot;
a wireless system information acquisition and holding unit that collects traffic data, which is data on transmission timing of traffic that the wireless communication device is trying to transmit and data on allowable delay, from the wireless communication device;
Based on the traffic data, for each traffic that the wireless communication device is trying to transmit, a counter value defined by the number of time slots, the counter value represented by an integer value in units of time slot length. a counter value setting unit for setting the counter value based on the data on the allowable delay included in the traffic data for each traffic that the wireless communication device is trying to transmit; ,
setting the same time slot transmission traffic number, which is the number of traffic to be transmitted in one time slot;
Determining whether the number of traffic candidates for transmission in one time slot is equal to or less than the same time slot transmission traffic number;
(1) When it is determined that the number of traffic candidates for transmission in one time slot is equal to or less than the number of traffic for transmission in the same time slot, all the traffic candidates for transmission are transmitted. (2) in one time slot, if it is determined that the number of traffic candidates for transmission is not equal to or less than the number of same-time-slot transmission traffic, and performing counter value sorting processing, which is a sorting processing for the counter values of the traffic that are candidates for transmission, and based on the result of the counter value sorting processing, the number of traffic that matches the number of traffic transmitted in the same time slot. and determining the selected traffic as traffic to be transmitted in one time slot;
Communication-related information of at least one of the wireless system and the wireless communication device, comprising: (1) packet generation cycle and/or packet generation timing, (2) packet size and/or traffic volume, and (3) allowable delay amount to each of the wireless communication devices included in the plurality of wireless systems, based on the communication-related information including and the information about the traffic to be transmitted in one time slot determined by the traffic adjustment processing unit a time slot allocation information generator for generating time slot allocation information, which is information on time slots to be allocated;
During a period specified by the time slots assigned by the time slot assignment information, the wireless communication device assigned by the time slot assignment information uses the channel used in the wireless communication system, a first communication processing unit for acquiring data for wireless communication by transmitting traffic determined as traffic to be transmitted in one time slot by the traffic adjustment unit;
a first communication interface for transmitting data acquired by the first communication processing unit to each wireless communication device;
A coordinator device comprising:

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