WO2024034051A1

WO2024034051A1 - Access point, wireless terminal device, and communication system

Info

Publication number: WO2024034051A1
Application number: PCT/JP2022/030557
Authority: WO
Inventors: 朗岸田; 健悟永田; 裕介淺井; 泰司鷹取
Original assignee: 日本電信電話株式会社
Priority date: 2022-08-10
Filing date: 2022-08-10
Publication date: 2024-02-15

Abstract

An access point according to an embodiment of the present invention comprises a first wireless signal processing unit and a first management unit. The first management unit uses the first wireless signal processing unit to establish a first link to the first wireless terminal device and a second link to the second wireless terminal device and sets a service period at a first cycle. The first management unit sets a transmission suppression period for providing a data transmission opportunity to the first wireless terminal device and suppressing or prohibiting data transmission by the second wireless terminal device in the service period and suppressing or prohibiting data transmission by the first wireless terminal device outside of the service period.

Description

Access points, wireless terminal devices, and communication systems

Embodiments relate to an access point, a wireless terminal device, and a communication system.

A wireless LAN (Local Area Network) is known as a communication system that wirelessly connects a base station and a wireless terminal device. By using a wireless LAN, a wireless terminal device can access a network via an access point within a communication area.

The challenge is to suppress delays in traffic transmitted wirelessly.

The access point of the embodiment includes a first wireless signal processing unit and a first management unit. The first management unit uses a first wireless signal processing unit to establish a first link with the first wireless terminal device and a second link with the second wireless terminal device, and Set the service period at the cycle of. The first management unit provides the first wireless terminal device with an opportunity to transmit data within the service period, and suppresses or prohibits the second wireless terminal device from transmitting data, and outside the service period, A transmission suppression period for suppressing or prohibiting data transmission by the first wireless terminal device is set.

The access point of the embodiment can suppress delays in traffic transmitted wirelessly.

FIG. 1 is a block diagram showing an example of the configuration of a communication system according to the first embodiment. FIG. 2 is a table showing an example of link management information of an access point included in the communication system according to the first embodiment. FIG. 3 is a time chart showing an overview of the rTWT function of the communication system according to the first embodiment. FIG. 4 is a block diagram illustrating an example of the hardware configuration of an access point included in the communication system according to the first embodiment. FIG. 5 is a block diagram illustrating an example of the hardware configuration of a wireless terminal device included in the communication system according to the first embodiment. FIG. 6 is a block diagram illustrating an example of a functional configuration of an access point included in the communication system according to the first embodiment. FIG. 7 is a block diagram illustrating an example of a functional configuration of a wireless terminal device included in the communication system according to the first embodiment. FIG. 8 is a block diagram illustrating an example of a configuration of a channel access function of an access point included in the communication system according to the first embodiment. FIG. 9 is a flowchart illustrating an example of a method for setting up the rTWT function of the communication system according to the first embodiment. FIG. 10 is a schematic diagram showing an example of the format of a beacon frame transmitted by an access point included in the communication system according to the first embodiment. FIG. 11 is a flowchart illustrating an example of a frame exchange method using the rTWT function of the communication system according to the first embodiment. FIG. 12 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system according to the first embodiment. FIG. 13 is a schematic diagram showing an example of parameters used to set a transmission suppression period by an access point included in the communication system according to the first embodiment. FIG. 14 is a block diagram illustrating an example of the functional configuration of an access point included in the communication system according to the second embodiment. FIG. 15 is a schematic diagram illustrating an example of the format of a transmission prohibited frame transmitted by an access point included in the communication system according to the second embodiment. FIG. 16 is a flowchart illustrating an example of a frame exchange method using the rTWT function of the communication system according to the second embodiment. FIG. 17 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system according to the second embodiment. FIG. 18 is a block diagram illustrating an example of the functional configuration of an access point included in the communication system according to the third embodiment. FIG. 19 is a flowchart illustrating an example of a frame exchange method of the communication system included in the communication system according to the third embodiment. FIG. 20 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system according to the third embodiment. FIG. 21 is a block diagram illustrating an example of the functional configuration of an access point included in the communication system according to the fourth embodiment. FIG. 22 is a block diagram illustrating an example of the functional configuration of a wireless terminal device included in the communication system according to the fourth embodiment. FIG. 23 is a flowchart illustrating an example of a frame exchange method using the rTWT function of the communication system according to the fourth embodiment. FIG. 24 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system according to the fourth embodiment. FIG. 25 is a block diagram illustrating an example of the functional configuration of a wireless terminal device included in the communication system according to the fifth embodiment. FIG. 26 is a flowchart illustrating an example of a frame exchange method of the communication system according to the fifth embodiment. FIG. 27 is a time chart showing a specific example of the frame exchange method of the communication system according to the fifth embodiment.

Each embodiment will be described below with reference to the drawings. Each embodiment exemplifies an apparatus or method for embodying the technical idea of the invention. The drawings may be schematic or conceptual. In the following description, common reference numerals are added to components having the same function and configuration.

<1> First Embodiment The communication system 1 according to the first embodiment provides a wireless terminal device that has been assigned a service period in which traffic requiring low delay can be exchanged preferentially. A period is provided outside the period in which traffic transmission is suppressed. Details of the communication system 1 according to the first embodiment will be described below.

<1-1> Configuration <1-1-1> Overall configuration of communication system 1 FIG. 1 is a block diagram showing an example of the configuration of communication system 1 according to the first embodiment. As shown in FIG. 1, the communication system 1 includes an access point AP and a wireless terminal device WTA.

The access point AP is a wireless LAN base station. The access point AP is configured to be able to communicate wirelessly with the wireless terminal device WTA, and is configured to be able to communicate with a server (not shown) on the network NW. The access point AP supports rTWT (restricted-Target Wake Time) function. The rTWT function is a function that allocates a service period in which traffic requiring low delay can be exchanged preferentially to a predetermined wireless terminal device WTA. Hereinafter, such a service period will be referred to as "rTWT service period SP", and traffic that requires low delay will be referred to as "low delay traffic".

The wireless terminal device WTA is a wireless terminal such as a smartphone or a PC (Personal Computer). The wireless terminal device WTA is configured to be able to communicate with a server on the network NW via the access point AP. Below, the wireless terminal device WTA that supports the rTWT function is referred to as the "EHT (Extremely High Throughput) terminal STA1", and the wireless terminal device WTA that does not support the rTWT function is referred to as the "legacy terminal STA2". call.

Communication between the access point AP and the wireless terminal device WTA is based on, for example, the IEEE802.11 standard. The IEEE 802.11 standard has a wireless communication function based on the OSI (Open Systems Interconnection) reference model. In the OSI reference model, wireless communication functions are divided into seven layers (1st layer: physical layer, 2nd layer: data link layer, 3rd layer: network layer, 4th layer: transport layer, 5th layer: session layer, Layer 6: Presentation layer; Layer 7: Application layer). The data link layer includes an LLC (Logical Link Control) sublayer and a MAC (Media Access Control) sublayer.

The access point AP manages a plurality of wirelessly connected wireless terminal devices WTA using link management information. FIG. 2 is a table showing an example of link management information of the access point AP according to the first embodiment. As shown in FIG. 2, the link management information includes, for example, information regarding "link ID", "link", "channel ID", and "rTWT function".

The "Link ID" item indicates the identifier of the link associated with the STA function of the access point AP and the wireless terminal device WTA. In this example, the link management information records information on the EHT terminal STA1 and the legacy terminal STA2.

The "Link" item indicates whether a link has been established with the associated link ID. This example shows that the access point AP has established links with each of the EHT terminal STA1 and the legacy terminal STA2 (FIG. 2: Yes).

The "Channel ID" item indicates the identifier of the channel used for the link. In this example, a common channel CH1 is assigned to each of the EHT terminal STA1 and the legacy terminal STA2.

The "rTWT function" item indicates whether or not the rTWT function is enabled. In this example, the rTWT function of the EHT terminal STA1 is enabled (FIG. 2: enabled). On the other hand, the rTWT function of the legacy terminal STA2 is disabled (FIG. 2: disabled).

In this specification, as explained above, the channel CH1 is shared by the EHT terminal STA1 and the legacy terminal STA2, and the access point AP uses the rTWT function to communicate wirelessly with each of the EHT terminal STA1 and the legacy terminal STA2. The case of communication will be explained.

(Overview of rTWT function)
FIG. 3 is a time chart showing an overview of the rTWT function of the communication system 1 according to the first embodiment. As shown in FIG. 3, the access point AP using the rTWT function sets a constant cycle (hereinafter referred to as a "TWT cycle"). FIG. 3 shows consecutive TWT intervals TI<1> and TI<2> among the TWT periods.

Each TWT interval TI corresponds to one TWT period. Each TWT interval TI includes an rTWT service period SP and a period OSP. The period OSP corresponds to a period that does not overlap with the rTWT service period SP, that is, outside the rTWT service period SP (outside the rTWT service period). Hereinafter, the start time of the rTWT service period SP will be referred to as "rTWT start time TS." The rTWT service period SP is determined by the rTWT start time TS and the rTWT duration period TD. The rTWT duration period TD indicates the length of the rTWT service period SP starting from the rTWT start time TS. The wireless terminal device WTA can recognize the time based on the rTWT start time TS and the TWT cycle (TWT interval TI) as the rTWT start time of the next rTWT service period SP. That is, the TWT interval TI corresponds to the interval between rTWT start times TS of adjacent rTWT service periods SP.

In the rTWT service period SP, the access point AP gives a frame exchange opportunity preferentially to the EHT terminal STA1, and sets a transmission suppression period QI to the legacy terminal STA2. A frame exchange opportunity corresponds to an opportunity for traffic (data) to be transmitted by frame exchange. The transmission suppression period QI corresponds to a period in which traffic transmission by the legacy terminal STA2 is suppressed. The transmission suppression period QI overlaps with the rTWT service period SP. Further, the transmission suppression period QI is set to be the same length as the rTWT service period SP or shorter than that. The access point AP can set the rTWT start time TS and rTWT duration TD for each link.

For example, the EHT terminal STA1 transmits low-latency traffic based on reception of a trigger frame within the rTWT service period SP. The access point AP may transmit a trigger frame to the EHT terminal STA1 at the rTWT start time TS. In the rTWT service period SP, the EHT terminal STA1 can preferentially transmit low-latency traffic, and can improve the latency of low-latency traffic. On the other hand, in the period OSP, each of the EHT terminal STA1 and the legacy terminal STA2 can obtain a frame exchange opportunity. The rTWT function in the first embodiment further sets a period outside the rTWT service period in which frame exchange by the EHT terminal STA1 is suppressed. Details of this operation will be described later.

Note that the TWT period is preferably set in accordance with the transmission period of low-delay traffic of the wireless terminal device WTA. Initial settings for rTWT functionality may be determined in various ways. For example, the initial settings of the rTWT function may use traffic attributes such as traffic occurrence interval and data amount notified from an application that generates low-latency traffic. In this case, the access point AP acquires the attributes of the corresponding traffic by notifying the server on the network NW of the type of traffic. Then, the access point AP determines the initial settings of the rTWT function based on the acquired traffic attributes.

<1-1-2> Hardware configuration of communication system 1 (Hardware configuration of access point AP)
FIG. 4 is a block diagram showing an example of the hardware configuration of the access point AP included in the communication system 1 according to the first embodiment. As shown in FIG. 4, the access point AP includes, for example, a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, a wireless communication module 14, and a wired communication module 15. .

The CPU 11 is an integrated circuit that can execute various programs, and controls the overall operation of the access point AP. The ROM 12 is a nonvolatile semiconductor memory, and stores programs, control data, etc. for controlling the access point AP. The RAM 13 is, for example, a volatile semiconductor memory, and is used as a work area for the CPU 11. The wireless communication module 14 is a circuit used for transmitting and receiving data using wireless signals, and is configured to be connectable to an antenna. The wired communication module 15 is a circuit used for transmitting and receiving data using wired signals, and is configured to be connectable to the network NW. Note that the access point AP may have other hardware configurations. For example, when the access point AP is wirelessly connected to the network NW, the wired communication module 15 may be omitted from the access point AP.

(Hardware configuration of wireless terminal device WTA)
FIG. 5 is a block diagram showing an example of the hardware configuration of the wireless terminal device WTA included in the communication system 1 according to the first embodiment. As shown in FIG. 5, the wireless terminal device WTA includes, for example, a CPU 21, a ROM 22, a RAM 23, a wireless communication module 24, a display 25, and a storage 26.

The CPU 21 is an integrated circuit capable of executing various programs, and controls the overall operation of the wireless terminal device WTA. The ROM 22 is a nonvolatile semiconductor memory, and stores programs, control data, etc. for controlling the wireless terminal device WTA. The RAM 23 is, for example, a volatile semiconductor memory, and is used as a work area for the CPU 21. The wireless communication module 24 is a circuit used for transmitting and receiving data using wireless signals, and is configured to be connectable to an antenna. The display 25 displays, for example, a GUI (Graphical User Interface) corresponding to application software. The display 25 may have a function as an input interface for the wireless terminal device WTA. The storage 26 is a nonvolatile storage device, and stores, for example, system software of the wireless terminal device WTA. Note that the wireless terminal device WTA may have other hardware configurations. For example, when the wireless terminal device WTA is an IoT (Internet of Things) terminal or the like, the display 25 may be omitted from the wireless terminal device WTA.

<1-1-3> Functional configuration of communication system 1 (Functional configuration of access point AP)
FIG. 6 is a block diagram showing an example of the functional configuration of the access point AP included in the communication system 1 according to the first embodiment. As shown in FIG. 6, the access point AP functions as a computer including, for example, an LLC processing section 110, a data processing section 120, a management section 130, a MAC frame processing section 140, and a wireless signal processing section 150. The LLC processing unit 110 is a functional block that executes processing corresponding to the LLC sublayer of the second layer and the third to seventh layers. The data processing unit 120, the management unit 130, and the MAC frame processing unit 140 are functional blocks that execute processing corresponding to the MAC sublayer of the second layer. The wireless signal processing unit 150 is a functional block that executes processing corresponding to the MAC sublayer of the second layer and the first layer.

The LLC processing unit 110 generates an LLC packet by adding, for example, a DSAP (Destination Service Access Point) header, a SSAP (Source Service Access Point) header, etc. to the data received from the network NW. The LLC processing unit 110 then inputs the generated LLC packet to the data processing unit 120. Further, the LLC processing unit 110 extracts data from the LLC packet input from the data processing unit 120. The LLC processing unit 110 then transmits the extracted data to the network NW.

The data processing unit 120 adds a MAC header to the LLC packet input from the LLC processing unit 110 to generate a MAC frame. The data processing unit 120 then inputs the generated MAC frame to the MAC frame processing unit 140. Furthermore, the data processing unit 120 extracts LLC packets from the MAC frame input from the MAC frame processing unit 140. The data processing unit 120 then inputs the extracted LLC packet to the LLC processing unit 110. A MAC frame containing data is also called a "data frame."

The management unit 130 manages the state of the link between the access point AP and the wireless terminal device WTA. Between the management unit 130 and the MAC frame processing unit 140, MAC frames containing management information regarding links, rTWT functions, etc. are input and output. A MAC frame containing management information is also called a "management frame." The management unit 130 includes, for example, link management information 131, a link control unit 132, a beacon management unit 133, and a transmission period management unit 134.

The link management information 131 includes information regarding the link between the access point AP and the wireless terminal device WTA that is wirelessly connected. The link management information 131 includes, for example, the information shown in FIG. 2. Further, the link management information 131 may include information regarding the settings of the rTWT function, such as the rTWT start time TS and the rTWT duration TD.

The link control unit 132 controls the establishment of a link between the access point AP and the wireless terminal device WTA. For example, the link control unit 132 executes an association process and a subsequent authentication process in response to a connection request from the wireless terminal device WTA. The link control unit 132 can control the state of the link established with the wireless terminal device WTA.

The beacon management unit 133 manages information transmitted by the access point AP as a beacon. Specifically, the beacon management unit 133 periodically generates a management frame including management information regarding the rTWT function, for example. The beacon management unit 133 then inputs the generated management frame to the MAC frame processing unit 140. That is, the beacon management unit 133 notifies the wireless terminal device WTA of the rTWT start time TS and the rTWT duration TD. The management frame generated by the beacon management unit 133 is also called a "beacon frame."

The transmission period management unit 134 manages the transmission suppression period RP. The transmission suppression period RP corresponds to a period during which frame exchange by the EHT terminal STA1 is suppressed when using the rTWT function. For example, the transmission period management unit 134 sets a transmission suppression period RP after the rTWT service period SP of each TWT interval TI.

The MAC frame processing unit 140 inputs the MAC frame input from the data processing unit 120 or the management unit 130 to the radio signal processing unit 150 corresponding to the link associated with the MAC frame. Further, the MAC frame processing section 140 inputs the MAC frame input from the radio signal processing section 150 to the data processing section 120 or the management section 130 depending on the type of the MAC frame. Specifically, the MAC frame processing unit 140 inputs the MAC frame to the data processing unit 120 when the MAC frame is a data frame. The MAC frame processing unit 140 inputs the MAC frame to the management unit 130 when the MAC frame is a management frame.

The radio signal processing unit 150 executes carrier sense. Carrier sense is a process for checking channel status. If the channel is busy, the radio signal processing unit 150 continues carrier sensing. When the channel is in an idle state, the radio signal processing unit 150 adds a preamble and the like to the MAC frame input from the MAC frame processing unit 140 to generate a radio frame. Then, the wireless signal processing unit 150 converts the generated wireless frame into a wireless signal (wireless medium), and radiates (transmits) the converted wireless signal via the antenna. The conversion process from a radio frame to a radio signal includes, for example, one of convolutional encoding processing, interleaving processing, subcarrier modulation processing, inverse fast Fourier transform processing, OFDM (Orthogonal Frequency Division Multiplexing) modulation processing, and frequency conversion processing. include. Furthermore, the radio signal processing unit 150 converts a radio signal received via an antenna into a radio frame. The conversion process from a radio signal to a radio frame includes, for example, any one of frequency conversion process, OFDM demodulation process, fast Fourier transform process, subcarrier demodulation process, deinterleaving process, and Viterbi decoding process. Then, the radio signal processing unit 150 extracts a MAC frame from the converted radio frame, and inputs the extracted MAC frame to the MAC frame processing unit 140. The wireless signal processing unit 150 may be referred to as an "STA function". The access point AP may include a plurality of radio signal processing units 150 each handling a different channel CH.

(Functional configuration of wireless terminal device WTA)
FIG. 7 is a block diagram showing an example of the functional configuration of the wireless terminal device WTA included in the communication system 1 according to the first embodiment. As shown in FIG. 7, the wireless terminal device WTA is a computer including, for example, an application execution unit 200, an LLC processing unit 210, a data processing unit 220, a management unit 230, a MAC frame processing unit 240, and a wireless signal processing unit 250. Function. The application execution unit 200 is a functional block that executes processing corresponding to the seventh layer. The LLC processing unit 210 is a functional block that executes processing corresponding to the LLC sublayer of the second layer and the third to sixth layers. The data processing section 220, the management section 230, and the MAC frame processing section 240 are functional blocks that execute processing corresponding to the MAC sublayer of the second layer. The wireless signal processing unit 250 is a functional block that executes processing corresponding to the MAC sublayer of the second layer and the first layer.

The application execution unit 200 executes an application based on data input from the LLC processing unit 210. Further, the application execution unit 200 inputs data to the LLC processing unit 210. For example, the application execution unit 200 can display application information on the display 25. Further, the application execution unit 200 can operate based on the operation of the input interface.

The LLC processing unit 210 adds a DSAP header, an SSAP header, etc. to the data input from the application execution unit 200, and generates an LLC packet. The LLC processing unit 210 then inputs the generated LLC packet to the data processing unit 220. Further, the LLC processing unit 210 extracts data from the LLC packet input from the data processing unit 120. The LLC processing unit 210 then inputs the extracted data to the application execution unit 200.

The data processing unit 220 adds a MAC header to the LLC packet input from the LLC processing unit 210 to generate a MAC frame. The data processing unit 220 then inputs the generated MAC frame to the MAC frame processing unit 240. Furthermore, the data processing unit 220 extracts LLC packets from the MAC frame input from the MAC frame processing unit 240. The data processing unit 220 then inputs the extracted LLC packet to the LLC processing unit 210.

The management unit 230 manages the state of the link between the access point AP and the wireless terminal device WTA. Between the management unit 230 and the MAC frame processing unit 240, MAC frames containing management information regarding links, rTWT functions, etc. are input and output. The management unit 230 includes, for example, link management information 231, a link control unit 232, and a beacon processing unit 233.

The link management information 231 includes information regarding the link between the wireless terminal device WTA and the wirelessly connected access point AP. The link management information 231 may also include information regarding the settings of the rTWT function (rTWT start time TS, rTWT duration TD, etc.).

The link control unit 232 controls the establishment of a link between the access point AP and the wireless terminal device WTA. For example, the link control unit 232 executes an association process and a subsequent authentication process when transmitting a connection request to the access point AP. The link control unit 232 can control the state of the link established with the access point AP.

The beacon processing unit 233 processes information included in the beacon received from the access point AP. Specifically, the beacon processing unit 233 extracts management information regarding the rTWT function from the beacon frame input from the MAC frame processing unit 240. Then, the beacon processing unit 233 associates the rTWT start time TS and the rTWT duration TD among the extracted management information regarding the rTWT function with the link to which the rTWT function is applied, and adds the rTWT function to the link management information 231, for example. Record. In other words, the beacon processing unit 233 extracts the period during which low-latency traffic is transmitted (rTWT service period SP) from the received beacon, and reflects it in the link management information 231. The beacon processing unit 233 may notify the data processing unit 220 of management information regarding the rTWT function.

The MAC frame processing unit 240 inputs the MAC frame input from the data processing unit 220 or the management unit 230 to the radio signal processing unit 250 corresponding to the link associated with the MAC frame. Furthermore, the MAC frame processing section 240 inputs the MAC frame input from the radio signal processing section 250 to the data processing section 220, the management section 230, or the radio signal processing section 250, depending on the type of the MAC frame. Specifically, the MAC frame processing unit 240 inputs the MAC frame to the data processing unit 220 when the MAC frame is a data frame. The MAC frame processing unit 240 inputs the MAC frame to the management unit 230 when the MAC frame is a management frame. For example, when the MAC frame is a beacon frame, the MAC frame processing unit 240 inputs the beacon frame to the beacon processing unit 233. The MAC frame processing section 240 outputs corresponding data to the radio signal processing section 250 when the MAC frame is a trigger frame. The trigger frame is a frame used when the access point AP requests the wireless terminal device WTA to transmit traffic.

The radio signal processing unit 250 executes carrier sense processing. If the channel is busy, the radio signal processing unit 250 continues carrier sense processing. When the channel is in an idle state, the radio signal processing unit 250 adds a preamble and the like to the MAC frame input from the MAC frame processing unit 240 to generate a radio frame. Then, the wireless signal processing unit 250 converts the generated wireless frame into a wireless signal (wireless medium), and radiates (transmits) the converted wireless signal via the antenna. The conversion process from a radio frame to a radio signal includes, for example, any one of convolutional encoding processing, interleaving processing, subcarrier modulation processing, inverse fast Fourier transform processing, OFDM modulation processing, and frequency conversion processing. Furthermore, the radio signal processing unit 250 converts a radio signal received via an antenna into a radio frame. The conversion process from a radio signal to a radio frame includes, for example, any one of frequency conversion process, OFDM demodulation process, fast Fourier transform process, subcarrier demodulation process, deinterleaving process, and Viterbi decoding process. Then, the radio signal processing unit 250 extracts a MAC frame from the converted radio frame, and inputs the extracted MAC frame to the MAC frame processing unit 240. The wireless signal processing unit 250 may be referred to as "STA function". The wireless terminal device WTA may include a plurality of wireless signal processing units 250 each handling a different channel CH.

(Configuration of channel access function of access point AP)
FIG. 8 is a block diagram illustrating an example of a configuration of a channel access function of the access point AP according to the first embodiment. As shown in FIG. 6, the wireless signal processing unit 150 of the access point AP includes, for example, a classification unit 151,

queues

152A, 152B, 152C, and 152D, carrier

sense execution units

153A, 153B, 153C, and 153D, and an internal collision management unit. 154 included.

When the MAC frame input from the MAC frame processing unit 240 is a data frame, the classification unit 151 classifies the data frame into a plurality of access categories based on the traffic type (TID) included in the MAC header. Examples of the traffic types include "VO (Voice)," "VI (Video)," "BE (Best Effort)," "BK (Background)," and "LL (Low Latency)." Then, the classification unit 151 inputs the data frame to the corresponding queue 152 among the plurality of

queues

152A, 152B, 152C, and 152D. In this example, the classification unit 151 inputs data frames corresponding to access categories VO, VI, BE, and BK to

queues

152A, 152B, 152C, and 152D, respectively. Furthermore, when the MAC frame input from the MAC frame processing unit 140 is a high priority frame such as a trigger frame, the classification unit 151 inputs the high priority frame to the internal collision management unit 154 without going through the queue 152, for example. .

Each of the plurality of

queues

152A, 152B, 152C, and 152D buffers input data frames. In this example,

multiple queues

152A, 152B, 152C, and 152D buffer data frames corresponding to access categories VO, VI, BE, and BK, respectively.

Each of the plurality of carrier

sense execution units

153A, 153B, 153C, and 153D is associated with the plurality of

queues

152A, 152B, 152C, and 152D, respectively. Each of the plurality of carrier

sense execution units

153A, 153B, 153C, and 153D executes carrier sense based on CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) according to preset access parameters. Access parameters are set for each access category, and are set, for example, so that wireless signal transmission is prioritized in the order of "VO", "VI", "BE", and "BK". If it is determined that the channel is in an idle state for a predetermined period of time, each of the plurality of carrier

sense execution units

153A, 153B, 153C, and 153D acquires the right to transmit a data frame and ends carrier sense. When it is determined that the channel is busy, each of the plurality of carrier

sense execution units

153A, 153B, 153C, and 153D stops acquiring the transmission right and ends carrier sense. The carrier sense execution unit 153 that has acquired the transmission right extracts the data frame from the associated queue 152 and outputs the extracted data frame to the internal collision management unit 154.

The internal collision management unit 154 prevents transmission collisions when a plurality of carrier sense execution units 153 acquire transmission rights at the same time. Specifically, when a plurality of data frames are input at the same time, the internal collision management unit 154 outputs a data frame of an access category with a high priority priority. The data frame output from the internal collision management unit 154 is converted into a radio frame and transmitted via an antenna.

When a high-priority frame such as a trigger frame is input, the radio signal processing unit 150 performs carrier sensing and transmits a radio signal including the high-priority frame via an antenna. Since carrier sensing is performed on high-priority frames without going through the queue 152, they can be processed with lower delay than other traffic. The radio signal processing unit 150 may temporarily stop carrier sensing of other queues 152 when transmitting a high priority frame. Furthermore, the radio signal processing unit 150 may generate a trigger frame based on the rTWT start time TS notified from the management unit 130.

As access parameters used in carrier sense, for example, CW (Contention Window) min, CWmax, AIFS (Arbitration Inter Frame Space), and TXOP (Transmission Opportunity) Limit are used. The contention window is a parameter used to determine the transmission waiting time for collision avoidance. CWmin and CWmax indicate the minimum and maximum values of the contention window, respectively. AIFS (Arbitration Inter Frame Space) indicates a fixed transmission waiting time set for each access category for collision avoidance control with a priority control function. TXOP corresponds to the channel occupancy time. TXOPLimit indicates the upper limit value of TXOP. The shorter the CWmin and CWmax, the easier it is for the queue 152 to obtain the transmission right. The priority of the queue 152 becomes higher as the AIFS becomes smaller. The amount of data transmitted with one transmission right increases as the value of TXOPLimit increases.

Note that the configuration regarding the channel access function of the wireless terminal device WTA is equivalent to the configuration regarding the channel access function of the access point AP. Although this specification exemplifies a case where the channel access function is implemented in the radio signal processing unit 150, the channel access function may also be implemented in the MAC frame processing unit 140. The access parameters may be called EDCA (Enhanced Distributed Channel Access) parameters.

<1-2> Operation <1-2-1> Method for setting up the rTWT function FIG. 9 is a flowchart showing an example of a method for setting up the rTWT function of the communication system 1 according to the first embodiment. A method for setting up the rTWT function will be described below with reference to FIG. The setup of the rTWT function is executed, for example, by transmitting and receiving management frames between the management unit 130 of the access point AP and the management unit 230 of the wireless terminal device WTA.

First, the EHT terminal STA1 notifies the access point AP of low-latency traffic transmission (S1). At this time, the EHT terminal STA1 also transmits, for example, information regarding the low-delay traffic generation cycle to the access point AP.

When the access point AP is notified of the transmission of low-latency traffic from the EHT terminal STA1, it sets up the rTWT function (S2). In setting up the rTWT function, the management unit 130 sets the rTWT start time TS, rTWT duration TD, and TWT cycle in accordance with the generation cycle of low-latency traffic, for example. The access point AP may obtain the low-latency traffic generation cycle using any method. For example, the access point AP may obtain information such as a data generation cycle set for an application that generates low-latency traffic from the wireless terminal device WTA, and use the information to set up the rTWT function.

When the setup of the rTWT function is completed, the access point AP updates the link management information 131 based on the established rTWT function setting (S3).

When the update of the link management information 131 is completed, the access point AP notifies the wireless terminal device WTA that the setup of the rTWT function is completed (S4). At this time, the access point AP also transmits the rTWT function settings (for example, rTWT service period SP, etc.) to the wireless terminal device WTA.

When the wireless terminal device WTA receives a notification that the setup of the rTWT function is completed from the access point AP, it updates the link management information 231 based on the notified setting of the rTWT function (S5). As a result, the link management information is updated in both the access point AP and the wireless terminal device WTA, and the setup of the rTWT function is completed. Thereafter, the access point AP and the wireless terminal device WTA can perform data communication using the rTWT function.

Note that the setup of the rTWT function may be performed at the time of link establishment. The change in the settings of the rTWT function may be executed by the access point AP or by the wireless terminal device WTA. The timing at which the access point AP acquires information on the wireless terminal device WTA (low-latency traffic generation cycle, etc.) used for setting the rTWT function is not particularly limited. The access point AP may notify the completion of setup of the rTWT function using a beacon. That is, the access point AP may notify the wireless terminal device WTA of the rTWT function setting using a beacon.

(Beacon frame format)
FIG. 10 is a schematic diagram showing an example of the format of a beacon frame transmitted by the access point AP included in the communication system 1 according to the first embodiment. As shown in FIG. 10, the beacon frame includes, for example, an rTWT start time TS, an rTWT duration TD, and a transmission suppression period QI as management information used in the rTWT function.

Upon receiving the beacon, the beacon processing unit 233 of each wireless terminal device WTA acquires the rTWT start time TS, rTWT duration TD, and transmission suppression period QI, and notifies the wireless signal processing unit 250 of the information. Thereby, the access point AP can voluntarily suppress the transmission of uplink data within the rTWT service period SP to the legacy terminal STA2 included in the plurality of wireless terminal devices WTA that are wirelessly connected. On the other hand, the wireless terminal device WTA to which communication is not assigned within the configured rTWT service period SP (that is, the EHT terminal STA1 that is not a member of the rTWT service period SP concerned) is configured by receiving the beacon. It is possible to suppress spontaneous transmission within the rTWT service period SP.

Note that the information indicating the transmission suppression period QI included in the beacon frame may be omitted when the rTWT continuation period TD and the transmission suppression period QI are the same length. In this case, the wireless terminal device WTA sets the period indicated by the input rTWT start time TS and rTWT duration TD as the transmission suppression period QI. That is, the radio signal processing unit 250 of the wireless terminal device WTA may suppress the transmission of traffic during the rTWT service period SP based on the rTWT start time TS and the rTWT duration period TD.

Additionally, the beacon frame may store management information used in the rTWT function for each identifier AID of the wireless terminal device WTA. The wireless terminal device WTA can refer to the AID and determine whether the management information is for its own station. Furthermore, the access point AP may manage management information used in the rTWT function for each group of wireless terminal devices WTA. In this case, the access point AP transmits a beacon that includes information on a set of an identifier of a group of wireless terminal devices WTA that share management information and an rTWT setting associated with the group.

<1-2-2> Frame Exchange Method FIG. 11 is a flowchart showing an example of a frame exchange method using the rTWT function of the communication system 1 according to the first embodiment. Below, with reference to FIG. 11, a frame exchange method using the rTWT function of the communication system 1 according to the first embodiment will be described, focusing on one TWT interval TI.

When the rTWT service period SP starts (start), frame exchange is performed preferentially between the access point AP and the EHT terminal STA1 (S11). During the rTWT service period SP, the traffic transmission of the legacy terminal STA2 is suppressed or prohibited because the transmission suppression period QI is set. Furthermore, the access point AP can record the transmission period (uplink/downlink/bidirectional) used by the EHT terminal STA1 during the rTWT service period SP.

When the frame exchange in the rTWT service period SP is completed, the access point AP calculates the period α (S12). The period α is calculated, for example, based on the information on the transmission period recorded in S11. A detailed example of the method for calculating the period α will be described later.

When the rTWT service period SP ends, a transmission suppression period RP starts, suppressing frame exchange between the access point AP and the EHT terminal STA1 for a period α, and preventing frame exchange between the access point AP and the legacy terminal STA2. It is executed (S13).

When the transmission suppression period RP ends, the period OSP starts. Then, each of the EHT terminal STA1 and the legacy terminal STA2 executes frame exchange with the access point AP under the same conditions (S14). When the period OSP ends (end), the access point AP completes the series of processes shown in FIG. 11 and starts processing the next rTWT service period SP.

(Specific example of frame replacement method)
FIG. 12 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system 1 according to the first embodiment. FIG. 12 shows the respective operations of the access point AP, the EHT terminal STA1, and the legacy terminal STA2 in one TWT interval TI. As shown in FIG. 12, in the TWT interval TI, for example, the rTWT service period SP, the transmission suppression period RP, and the period OSP are arranged in this order.

In the rTWT service period SP, frame exchange is performed between the EHT terminal STA1 and the access point AP. That is, in the rTWT service period SP, the EHT terminal STA1 can transmit low-latency traffic to the access point AP. Further, the transmission suppression period QI is set to overlap with the entire rTWT service period SP. As a result, during the rTWT service period SP, frame exchange between the legacy terminal STA2 and the access point AP is suppressed or prohibited, and frame exchange between the EHT terminal STA1 and the access point AP is prioritized.

The length of the transmission suppression period RP corresponds to the period α calculated by the access point AP. During the transmission suppression period RP, frame exchange between the EHT terminal STA1 and the access point AP is suppressed or prohibited. On the other hand, frame exchange between the legacy terminal STA2 and the access point AP is possible during the transmission suppression period RP. As a result, frame exchange between the legacy terminal STA2 and the access point AP is prioritized during the transmission suppression period RP.

In the period OSP, frame exchanges between the EHT terminal STA1 and the access point AP and frame exchanges between the legacy terminal STA2 and the access point AP are performed in accordance with the transmission right acquisition order according to predetermined access parameters. Ru. In the period OSP of this example, frame exchange is executed in the order of legacy terminal STA2 and EHT terminal STA1. It may be changed based on the traffic amount of the device WTA, etc.

Note that the transmission suppression period RP may be arranged to divide the period OSP. The period OSP may be associated with a period outside the rTWT service period SP and outside the transmission suppression period RP.

(How to set the transmission suppression period)
FIG. 13 is a schematic diagram showing an example of parameters used to set the transmission suppression period RP by the access point AP included in the communication system 1 according to the first embodiment. Each of (1) to (4) in FIG. 13 corresponds to the conditions used to calculate the period α, and shows the respective operations of the access point AP and the EHT terminal STA1 during the rTWT service period SP. The access point AP uses any of the first to fourth conditions explained below to determine the length of the rTWT service period SP or the frame exchange with the EHT terminal STA1 performed within the rTWT service period SP. The length of the transmission suppression period RP (period α) is set based on the length of the period.

The first condition will be explained with reference to (1) in FIG. When using the first condition, the access point AP calculates a value obtained by multiplying the length t1 of the rTWT service period SP by a predetermined coefficient as the period α. That is, the access point AP using the first condition calculates "α=t1×β" in the process of S12. The first condition does not depend on the length of the period or the number of times frame exchange is performed in the rTWT service period SP.

The second condition will be explained with reference to (2) in FIG. When using the second condition, the access point AP calculates a value obtained by multiplying the total time required for frame exchange between the access point AP and the EHT terminal STA1 by a predetermined coefficient γ during the rTWT service period SP using CSMA/CA. is calculated as period α. For example, the time required for frame exchange between the access point AP and the EHT terminal STA1 using CSMA/CA is the time required for the frame exchange between the access point AP and the EHT terminal STA1. This corresponds to the time t2 from the time to when the EHT terminal STA1 receives a confirmation frame ACK indicating successful reception of the MSDU by the access point AP. MSDU is a unit of data handled by the LLC layer. When frame exchange is performed twice in the rTWT service period SP, the access point AP using the second condition calculates "α=(t2a+t2b)×γ" in the process of S12. That is, the second condition is based on the interval between the MSDU transmission start time and the confirmation frame ACK reception completion time.

The third condition will be explained with reference to (3) in FIG. When using the third condition, the access point AP exchanges frames between the access point AP and the EHT terminal STA1 using CSMA/CA using RTS (Request To Send) and CTS (Clear To Send) during the rTWT service period SP. The period α is calculated by multiplying the total time required by a predetermined coefficient δ. For example, the time required for frame exchange between the access point AP and the EHT terminal STA1 using CSMA/CA using RTS and CTS is as follows: corresponds to the time t3 until the end of the transmission of the confirmation frame ACK indicating successful reception of the MSDU associated with the RTS. When frame exchange is performed twice in the rTWT service period SP, the access point AP using the third condition calculates “α=(t3a+t3b)×δ” in the process of S12. That is, the third condition is based on the interval between the RTS transmission start time and the confirmation frame ACK reception completion time.

The fourth condition will be explained with reference to (4) in FIG. When using the fourth condition, the access point AP calculates a value obtained by multiplying the total time required for frame exchange between the access point AP and the EHT terminal STA1 by a predetermined coefficient ε during the rTWT service period SP using the trigger frame TF. is calculated as period α. For example, the time required for frame exchange between the access point AP and the EHT terminal STA1 using the trigger frame TF is as follows. corresponds to the time t4 until the transmission of the confirmation frame ACK indicating successful reception of the MSDU associated with the MSDU is completed. When frame exchange is performed twice in the rTWT service period SP, the access point AP using the fourth condition calculates "α=(t4a+t4b)×ε" in the process of S12. That is, the fourth condition is based on the interval between the transmission start time of the trigger frame TF and the reception completion time of the confirmation frame ACK.

<1-3> Effects of the first embodiment According to the communication system 1 according to the first embodiment, delays in traffic transmitted wirelessly can be suppressed. Details of the effects of the first embodiment will be described below.

In wireless communication systems, the rTWT function is known as a function that preferentially secures transmission opportunities for low-latency traffic. The access point AP that uses the rTWT function has an rTWT service period SP that allows the EHT terminal STA1 to transmit low-latency traffic, and a transmission suppression that prohibits the transmission of traffic (data) by the legacy terminal STA2 that does not support the rTWT function. The schedule is made so as to overlap with the period QI. If the transmission suppression period QI matches the length of the rTWT service period SP, the legacy terminal STA2 cannot transmit data during the rTWT service period SP even if it holds data in the transmission queue. Furthermore, outside the rTWT service period SP, the EHT terminal STA1 and the legacy terminal STA2 equally perform contention operations for acquiring the channel transmission right, which may cause unfair opportunities to acquire the transmission right.

Therefore, after the rTWT service period SP ends, the communication system 1 according to the first embodiment sets a transmission suppression period RP for suppressing frame transmission for a certain period for the EHT terminal STA1. By setting the transmission suppression period RP, a transmission opportunity is secured for the legacy terminal STA2 that does not support the rTWT function. For example, the access point AP sets the length of the transmission suppression period RP (period α) based on the transmission period (uplink/downlink/bidirectional) used by the subordinate EHT terminal STA1 during the rTWT service period SP. obtain.

As a result, during the transmission suppression period RP, the legacy terminal STA2, which was unable to communicate during the rTWT service period SP, avoids competition for channel access rights with the EHT terminal STA1, which communicated with priority during the rTWT service period SP. can do. In other words, the communication system 1 according to the first embodiment maintains fairness in transmission opportunities between the wireless terminal device WTA that uses the rTWT function and the wireless terminal device WTA that does not use the rTWT function, and reduces traffic by the legacy terminal STA2. It is possible to secure transmission opportunities. Therefore, the communication system 1 according to the first embodiment can suppress delays in traffic transmitted wirelessly in each of the EHT terminal STA1 and the legacy terminal STA2.

Note that if the EHT terminal STA1 does not perform frame exchange during the rTWT service period SP, the transmission suppression period RP in the TWT interval TI may be omitted. In this case, the access point AP uses, for example, any of the second to fourth conditions explained using FIG. 13 to calculate the period α.

<2> Second Embodiment In the communication system 1 according to the second embodiment, the access point AP sets a transmission suppression period RPa by transmitting a radio frame instructing prohibition of transmission to the STA1 of the low delay group. Details of the communication system 1 according to the second embodiment will be described below.

<2-1> Configuration The hardware configuration of the communication system 1 according to the second embodiment is the same as that of the communication system 1 according to the first embodiment. The communication system 1 according to the second embodiment differs from the communication system 1 according to the first embodiment in the functional configuration of the access point AP.

(Functional configuration of access point APa)
FIG. 14 is a block diagram illustrating an example of a functional configuration of an access point APa included in the communication system 1 according to the second embodiment. As shown in FIG. 14, the access point APa functions as a computer including, for example, an LLC processing section 110, a data processing section 120, a management section 130a, a MAC frame processing section 140, and a wireless signal processing section 150. The management section 130a includes link management information 131, a link control section 132, a beacon management section 133, a transmission period management section 134, and a transmission prohibited frame generation section 135.

The transmission prohibited frame generation unit 135 generates a transmission prohibited frame. The transmission prohibited frame is a high priority frame, for example, a trigger frame. The transmission prohibition frame instructs the wireless terminal device WTA (EHT terminal STA1) that communicated during the rTWT service period SP to prohibit frame exchange for a certain period of time outside the rTWT service period SP. This fixed period is based on, for example, the period α calculated by the transmission period management unit 134. Then, the transmission prohibited frame generation unit 135 transmits the generated transmission prohibited frame to the EHT terminal STA1 via the MAC frame processing unit 140 and the wireless signal processing unit 150.

Note that in the second embodiment, the transmission period management unit 134 may perform timer management after the transmission prohibited frame is transmitted by the transmission prohibited frame generation unit 135. The other functional configurations of the communication system 1 according to the second embodiment are the same as those of the communication system 1 according to the first embodiment.

(Format of transmission prohibited frame)
FIG. 15 is a schematic diagram illustrating an example of the format of a transmission prohibited frame transmitted by the access point APa included in the communication system 1 according to the second embodiment. FIG. 15 illustrates a case where the transmission prohibited frame is a trigger frame. As shown in FIG. 15, the plurality of fields included in the transmission prohibited frame are, for example, a frame control field, a duration field, an address field (RA and TA), a common information field, a user information list field, a padding field, and an FCS ( Frame Check Sequence) field.

The frame control field stores various control information. For example, the frame control field includes information indicating the frame type of the wireless frame. The duration field indicates the scheduled period of time during which the wireless line will be used. The address field indicates the BSSID, source address, destination address, sender terminal address, receiver terminal address, etc. The common information field includes information indicating the trigger frame type and the like. The user information list field includes, for example, "AID" and "RU (Resource Unit) Allocation." The wireless terminal device WTA recognizes from the AID that the assignment is for its own station. Furthermore, the wireless terminal device WTA recognizes the allocated resources based on the RU allocation. Padding is an area for adjusting the data length of a radio frame. The FCS field stores an error detection code for the MAC header and frame body field, and is used to determine whether or not there is an error in the data frame.

When the trigger frame is used as a transmission prohibited frame, the allocation of communication resources (frequency, transmission timing, period) to the specific wireless terminal device WTA is set to "0". As a result, communication of the specific wireless terminal device WTA (EHT terminal STA1) is prohibited for a certain period (transmission suppression period RPa). Note that the transmission prohibited frame may be a frame (for example, an EHT action frame or a uniquely defined frame) that can be referenced by the wireless terminal devices WTA of the group that share the rTWT service period SP.

<2-2> Frame Exchange Method FIG. 16 is a flowchart showing an example of a frame exchange method using the rTWT function of the communication system 1 according to the second embodiment. Below, with reference to FIG. 16, a frame exchange method using the rTWT function of the communication system 1 according to the second embodiment will be described, focusing on one TWT interval TI.

When the rTWT service period SP starts (start), frame exchange is performed preferentially between the access point APa and the EHT terminal STA1, similarly to the access point AP of the first embodiment (S11).

When the frame exchange in the rTWT service period SP is completed, the access point APa calculates the period α similarly to the access point AP of the first embodiment (S12).

When the rTWT service period SP ends, the transmission suppression period RPa starts. Then, the access point APa transmits to the EHT terminal STA1 a transmission prohibition frame with a duration (duration of the transmission suppression period RPa)=α (S21). Specifically, the transmission period management unit 134 notifies the transmission prohibited frame generation unit 135 of the period α during which the EHT terminal STA1 is prohibited from exchanging frames. Then, the transmission prohibited frame generation unit 135 generates a transmission prohibited frame with duration=α based on the information notified to the transmission period management unit 134. Then, the transmission prohibited frame generation unit 135 transmits the generated transmission prohibited frame to the EHT terminal STA1 via the MAC frame processing unit 140 and the wireless signal processing unit 150. In other words, the EHT terminal STA1 that has received the transmission prohibited frame sets a NAV (Network Allocation Vector: transmission prohibited period) and suppresses (prohibits) transmission during the period α indicated by the duration value.

As a result, during the transmission suppression period RPa, frame exchange between the access point APa and the EHT terminal STA1 is prohibited for the period α, and frame exchange is executed between the access point APa and the legacy terminal STA2 (S22).

When the transmission suppression period RPa ends, the period OSP starts. Then, similarly to the first embodiment, each of the EHT terminal STA1 and the legacy terminal STA2 executes frame exchange with the access point APa under the same conditions (S14). When the period OSP ends (ends), the access point APa completes the series of processes shown in FIG. 16 and starts the process of the next rTWT service period SP.

Note that the transmission timing of the transmission prohibited frame in the process of S21 is, for example, the end time of the rTWT service period SP. In order to transmit the transmission prohibited frame at the end time of the rTWT service period SP, the access point APa may have the radio signal processing unit 150 transmit the transmission prohibited frame using the access category with the highest priority. Alternatively, the access point APa may transmit the transmission prohibited frame using a preferential transmission means different from the access category.

(Specific example of frame replacement method)
FIG. 17 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system 1 according to the second embodiment. FIG. 17 extracts and displays the rTWT service period SP and transmission suppression period RPa included in one TWT interval TI, and shows the respective operations of the access point APa, the EHT terminal STA1, and the legacy terminal STA2.

As shown in FIG. 17, during the rTWT service period SP, frame exchange may be performed between the EHT terminal STA1 and the access point APa, similarly to the first embodiment. Furthermore, during the transmission suppression period QI set in the rTWT service period SP, the legacy terminal STA2 defers frame transmission, that is, is on standby.

When the rTWT service period SP ends, the access point APa transmits a transmission prohibition frame to the EHT terminal STA1. Then, the NAV is set in the EHT terminal STA1 that received the transmission prohibited frame. The period during which the NAV is set for the EHT terminal STA1 corresponds to the transmission suppression period RPa. Then, during the transmission suppression period RPa, the legacy terminal STA2 may exchange frames with the access point APa. Thereby, during the transmission suppression period RPa, priority is given to frame exchange between the legacy terminal STA2 and the access point APa. Other operations of the communication system 1 according to the second embodiment are the same as those of the communication system 1 according to the first embodiment.

<2-3> Effects of the second embodiment As explained above, the communication system 1 according to the second embodiment has a transmission suppression period RPa in which frame exchange by the EHT terminal STA1 is suppressed based on the transmission prohibited frame. Set. As a result, the communication system 1 according to the second embodiment can maintain fairness in transmission opportunities between the wireless terminal device WTA that uses the rTWT function and the wireless terminal device WTA that does not use the rTWT function. Therefore, similarly to the first embodiment, the communication system 1 according to the second embodiment can suppress delays in traffic transmitted wirelessly in each of the EHT terminal STA1 and the legacy terminal STA2.

<3> Third Embodiment In the communication system 1 according to the third embodiment, the EHT terminal STA1 uses the RTS (Request To Send)/CTS (Clear To Send) procedure, and the access point AP responds to the RTS of the EHT terminal STA1. The transmission suppression period RPb is set by providing a period during which the response is omitted. Below, details of the communication system 1 according to the third embodiment will be explained.

<3-1> Configuration The hardware configuration of the communication system 1 according to the third embodiment is the same as the communication system 1 according to the first embodiment. The communication system 1 according to the third embodiment differs from the communication system 1 according to the first embodiment in the functional configuration of the access point AP.

(Functional configuration of access point APb)
FIG. 18 is a block diagram showing an example of the functional configuration of the access point APb included in the communication system 1 according to the third embodiment. As shown in FIG. 18, the access point APb functions as a computer including, for example, an LLC processing section 110, a data processing section 120, a management section 130b, a MAC frame processing section 140, and a wireless signal processing section 150. The management section 130b includes link management information 131, a link control section 132, a beacon management section 133, a transmission period management section 134, and a transmission prohibited terminal determination section 136.

The transmission prohibited terminal determination unit 136 checks the type of the wireless terminal device WTA that transmitted the RTS received by the access point APb during the transmission suppression period RPb notified by the transmission period management unit 134. Then, when the transmission prohibited terminal determination unit 136 receives the RTS transmitted by the EHT terminal STA1, it omits the CTS response to the EHT terminal STA1. On the other hand, when receiving the RTS transmitted by the legacy terminal STA2, the transmission-prohibited terminal determination unit 136 causes the CTS for the legacy terminal STA2 to be transmitted via the MAC frame processing unit 140 and the radio signal processing unit 150.

Note that the management unit 130b uses RTS/CTS to transmit uplink data during the transmission suppression period RPb following the rTWT service period SP to the wireless terminal device WTA (EHT terminal STA1) that communicated during the rTWT service period SP. may be required to be used. The transmission prohibited terminal determining unit 136 may return a CTS to the RTS of the EHT terminal STA1 and permit the EHT terminal STA1 to communicate if there is sufficient communication resources during the transmission suppression period RPb. In the transmission suppression period RPb following the rTWT service period SP, the RTS/CTS procedure is used only for the wireless terminal device WTA (EHT terminal STA1) that communicated in the rTWT service period SP, and the legacy terminal STA2 uses the RTS/CTS procedure. It is also possible to communicate with the access point APb without using any means. The other functional configurations of the communication system 1 according to the third embodiment are the same as those of the communication system 1 according to the first embodiment.

<3-2> Frame Exchange Method FIG. 19 is a flowchart showing an example of a frame exchange method using the rTWT function of the communication system 1 according to the third embodiment. Below, with reference to FIG. 19, a frame exchange method using the rTWT function of the communication system 1 according to the first embodiment will be described, focusing on one TWT interval TI.

When the rTWT service period SP starts (start), frames are exchanged preferentially between the access point APb and the EHT terminal STA1, similarly to the access point AP of the first embodiment (S11).

When the frame exchange in the rTWT service period SP is completed, the access point APb calculates the period α similarly to the access point AP of the first embodiment (S12).

When the rTWT service period SP ends, a transmission suppression period RPb starts. Then, during the period α, the EHT terminal STA1 uses the RTS/CTS procedure, and the access point APb executes frame exchange with the legacy terminal STA2 with a setting that does not return CTS in response to the RTS of the EHT terminal STA1 (S31 ).

When the transmission suppression period RPb ends, the period OSP starts. Then, similarly to the access point AP of the first embodiment, each of the EHT terminal STA1 and the legacy terminal STA2 executes frame exchange with the access point APb under the same conditions (S14). When the period OSP ends (end), the access point APb completes the series of processes shown in FIG. 19 and starts the process of the next rTWT service period SP.

(Specific example of frame replacement method)
FIG. 20 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system 1 according to the third embodiment. FIG. 20 extracts and displays the rTWT service period SP and transmission suppression period RPb included in one TWT interval TI, and shows the respective operations of the access point APb, the EHT terminal STA1, and the legacy terminal STA2.

As shown in FIG. 20, during the rTWT service period SP, frame exchange may be performed between the EHT terminal STA1 and the access point APb, similar to the first embodiment. Furthermore, during the transmission suppression period QI set in the rTWT service period SP, the legacy terminal STA2 defers frame transmission, that is, is on standby.

When the rTWT service period SP ends, the access point APb sets a transmission suppression period RPb. During the transmission suppression period RPb, the EHT terminal STA1 may transmit RTS to the access point APb according to predetermined access parameters. However, the access point APb ignores the RTS from the EHT terminal STA1 and omits the transmission of the CTS to the EHT terminal STA1 during the transmission suppression period RPb. On the other hand, the access point APb transmits a CTS in response to the RTS from the legacy terminal STA2 during the transmission suppression period RPb. Then, the legacy terminal STA2 that received the CTS transmits data (MSDU) to the access point APb.

In this way, during the transmission suppression period RPb, the legacy terminal STA2 can exchange frames with the access point APb. Therefore, during the transmission suppression period RPb, priority is given to frame exchange between the legacy terminal STA2 and the access point APb.

Note that the legacy terminal STA2 may communicate with the access point APb using means other than the RTS/CTS procedure during the transmission suppression period RPb. For example, the legacy terminal STA2 may use the method described using FIGS. 12 and 17 to exchange frames with the access point APb during the transmission suppression period RPb. Other operations of the communication system 1 according to the third embodiment are the same as those of the communication system 1 according to the first embodiment.

<3-3> Effects of the third embodiment As explained above, in the communication system 1 according to the third embodiment, the access point APb determines the wireless terminal device WTA with which the frame is to be exchanged, so that the EHT terminal A transmission suppression period RPb is set to suppress frame exchange by STA1. As a result, the communication system 1 according to the third embodiment can maintain fairness in transmission opportunities with the wireless terminal device WTA that does not use the rTWT function. Therefore, similarly to the first embodiment, the communication system 1 according to the third embodiment can suppress delays in traffic transmitted wirelessly in each of the EHT terminal STA1 and the legacy terminal STA2.

Note that during the transmission suppression period RPb, a CTS reply to the RTS transmitted from the EHT terminal STA1 that executed frame exchange during the rTWT service period SP may be permitted. In this case, the response frequency of CTS to RTS during the transmission suppression period RPb may be set lower in the EHT terminal STA1 than in the legacy terminal STA2.

<4> Fourth Embodiment In the communication system 1 according to the fourth embodiment, the EHT terminal STA1 transmits uplink data by using access parameters with a low priority for transmitting uplink data during the period notified from the access point AP. Set a suppression period RPc. Details of the communication system 1 according to the fourth embodiment will be described below.

<4-1> Configuration The hardware configuration of the communication system 1 according to the fourth embodiment is the same as the communication system 1 according to the first embodiment. The communication system 1 according to the fourth embodiment is different from the communication system 1 according to the first embodiment in the functional configurations of the access point AP and the wireless terminal device WTA.

(Functional configuration of access point APc)
FIG. 21 is a block diagram showing an example of the functional configuration of the access point APc included in the communication system 1 according to the fourth embodiment. As shown in FIG. 21, the access point APc functions as a computer including, for example, an LLC processing section 110, a data processing section 120, a management section 130c, a MAC frame processing section 140, and a wireless signal processing section 150. The management section 130c includes link management information 131, a link control section 132, a beacon management section 133, a transmission period management section 134, and an rTWT setting notification section 137.

The rTWT setting notification unit 137 manages parameters to be set in the EHT terminal STA1 during the transmission suppression period RPc. Then, the rTWT setting notification unit 137 notifies the EHT terminal STA1 of the parameters using a predetermined method. This predetermined method may be to generate a control frame including parameters and transmit it to the EHT terminal STA1, or may cause the beacon management unit 133 to transmit a beacon including the parameters. This parameter is a parameter arbitrarily determined by the access point APc, and is, for example, an access parameter such as AIFS or CW for determining a backoff value. During the transmission suppression period RPc, the access parameters applied to the EHT terminal STA1 are, for example, conditions that are more disadvantageous than the wireless terminal device WTA with which it is not communicating during the rTWT service period SP, and the access parameters applied to the EHT terminal STA1 are The access parameters are set to have lower priority than the access parameters set in .

(Functional configuration of wireless terminal device WTAa)
FIG. 22 is a block diagram showing an example of the functional configuration of the wireless terminal device WTAa included in the communication system 1 according to the fourth embodiment. As shown in FIG. 22, the wireless terminal device WTAa is a computer including, for example, an application execution unit 200, an LLC processing unit 210, a data processing unit 220, a management unit 230a, a MAC frame processing unit 240, and a wireless signal processing unit 250. Function. The management unit 230a includes, for example, link management information 231, a link control unit 232a, a beacon processing unit 233, and a transmission period management unit 234.

The transmission period management unit 234 manages information on the transmission suppression period RPc notified from the access point APc and the access parameters of the EHT terminal STA1 applied during the transmission suppression period RPc. The transmission period management unit 234 instructs the link control unit 232a to change the access parameters during the transmission suppression period RPc based on the management information of the rTWT function recorded in the link management information 231. The link control unit 232a changes the access parameters during the transmission suppression period RPc based on instructions from the transmission period management unit 234. In other words, the transmission period management section 234 causes the link control section 232a to change the parameters for acquiring the channel transmission right, based on the information on the transmission suppression period RPc notified from the access point APc. The other functional configurations of the communication system 1 according to the fourth embodiment are the same as those of the communication system 1 according to the first embodiment.

<4-2> Frame Exchange Method FIG. 23 is a flowchart showing an example of a frame exchange method using the rTWT function of the communication system according to the fourth embodiment. Below, with reference to FIG. 23, a frame exchange method using the rTWT function of the communication system 1 according to the fourth embodiment will be described, focusing on one TWT interval TI.

When the rTWT service period SP starts (start), frame exchange is performed preferentially between the access point APc and the EHT terminal STA1, similarly to the access point AP of the first embodiment (S11).

When the frame exchange in the rTWT service period SP is completed, the access point APc calculates the period α similarly to the access point AP of the first embodiment (S12).

When the rTWT service period SP ends, a transmission suppression period RPc starts. Then, during the period α, frames are exchanged with each of the EHT terminal STA1 and the legacy terminal STA2 with the access parameter of the EHT terminal STA1 set to have lower priority than that of the legacy terminal STA2 (S41). That is, during the transmission suppression period RPc, access parameters that are more advantageous to the legacy terminal STA2 that has not performed frame exchange are applied to the EHT terminal STA1 that has performed frame exchange during the rTWT service period SP. Therefore, during the transmission suppression period RPc, the legacy terminal STA2 becomes easier to acquire the channel transmission right than the EHT terminal STA1 with which it communicated during the rTWT service period SP. Note that in the process of S41, the access point APc may set the access parameters of the EHT terminal STA1 that did not perform frame exchange in the immediately preceding rTWT service period SP to the same priority level as the legacy terminal STA2.

When the transmission suppression period RPc ends, the period OSP starts. Then, similarly to the access point AP of the first embodiment, each of the EHT terminal STA1 and the legacy terminal STA2 executes frame exchange with the access point APc under the same conditions (S14). When the period OSP ends (end), the access point APc completes the series of processes shown in FIG. 23 and starts the process of the next rTWT service period SP.

Note that the access point APc may notify the EHT terminal STA1 of the access parameters temporarily applied during the transmission suppression period RPc by sequentially transmitting control frames. However, the access parameters temporarily applied during the transmission suppression period RPc may be notified to the EHT terminal STA1 at the time of setting up the rTWT function (for example, the process of S7 in FIG. 9). That is, the access point APc may transmit a frame including access parameters temporarily applied during the transmission suppression period RPc to the EHT terminal STA1 before the start of the transmission suppression period RPc.

As explained above, the EHT terminal STA1 in the fourth embodiment receives the first information including the information of the periodic rTWT service period SP from the access point APc, and can transmit data in the rTWT service period SP. . Then, the EHT terminal STA1 receives second information including information on the transmission suppression period RPc outside the rTWT service period SP from the access point APc, and can suppress or prohibit data transmission during the transmission suppression period RPc.

(Specific example of frame replacement method)
FIG. 24 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system according to the fourth embodiment. FIG. 24 extracts and displays the rTWT service period SP and transmission suppression period RPc included in one TWT interval TI, and shows the respective operations of the access point APc, the EHT terminal STA1, and the legacy terminal STA2.

As shown in FIG. 24, during the rTWT service period SP, frame exchange may be performed between the EHT terminal STA1 and the access point APc, similar to the access point AP of the first embodiment. Furthermore, during the transmission suppression period QI set in the rTWT service period SP, the legacy terminal STA2 defers frame transmission.

When the rTWT service period SP ends, a transmission suppression period RPc that has been set in advance between the access point APc and the EHT terminal STA1 starts. During the transmission suppression period RPc, the EHT terminal STA1 attempts to acquire the transmission right according to an access parameter that has lower priority than the legacy terminal STA2. On the other hand, the legacy terminal STA2 attempts to acquire the transmission right according to the access parameter with higher priority than the EHT terminal STA1. Therefore, during the transmission suppression period RPc, it becomes easier for the legacy terminal STA2 to acquire the transmission right than the EHT terminal STA1.

Specifically, in this example, when the transmission suppression period RPc starts, the DIFS+backoff count (A) of the EHT terminal STA1 and the DIFS+backoff count (B) of the legacy terminal STA2 start. Then, since the backoff value of the EHT terminal STA1 is set larger than the backoff value of the legacy terminal STA2, the legacy terminal STA2 obtains the transmission right first and transmits the MSDU to the access point APc. EHT terminal STA1 is set to NAV while legacy terminal STA2 is performing frame exchange with access point APc.

When the confirmation frame ACK based on the completion of transmission of the MSDU is transmitted, the DIFS + leftover backoff count (C) of the EHT terminal STA1 and the DIFS + backoff count (D) of the legacy terminal STA2 start. . In this example, since the leftover backoff value of the EHT terminal STA1 is larger than the backoff value of the legacy terminal STA2, the legacy terminal STA2 obtains the transmission right again and transmits the MSDU to the access point APc. EHT terminal STA1 is set to NAV while legacy terminal STA2 is performing frame exchange with access point APc.

When the confirmation frame ACK based on the completion of transmission of the MSDU is transmitted, the DIFS + leftover backoff count (E) of the EHT terminal STA1 and the DIFS + backoff count (F) of the legacy terminal STA2 start. . In this example, since the leftover backoff value of the EHT terminal STA1 is now smaller than the backoff value of the legacy terminal STA2, the EHT terminal STA1 obtains the transmission right and transmits the MSDU to the access point APc. Legacy terminal STA2 is set to NAV while EHT terminal STA1 is performing a frame exchange with access point APc.

As explained above, during the transmission suppression period RPc, the frequency of frame exchange between the legacy terminal STA2 and the access point APc is higher than the frequency of frame exchange between the EHT terminal STA1 and the access point APc. That is, during the transmission suppression period RPc, frame exchange of the legacy terminal STA2 is executed with priority. Note that the low priority setting of the access parameter may be realized not by the magnitude of the backoff value but by other parameters. Other operations of the communication system 1 according to the fourth embodiment are the same as those of the communication system 1 according to the first embodiment.

<4-3> Effects of the fourth embodiment As explained above, in the communication system 1 according to the fourth embodiment, the EHT terminal STA1 lowers the priority of the access parameter after the rTWT service period SP, A transmission suppression period RPc is set to suppress frame exchange by the EHT terminal STA1. As a result, the communication system 1 according to the fourth embodiment can maintain fairness in transmission opportunities with the wireless terminal device WTA that does not use the rTWT function. Therefore, similarly to the first embodiment, the communication system 1 according to the fourth embodiment can suppress delays in traffic transmitted wirelessly in each of the EHT terminal STA1 and the legacy terminal STA2.

Note that in the fourth embodiment, a case has been described in which the access parameters (EDCA parameters) are set to low priority in order to reduce the transmission frequency of the EHT terminal STA1 during the transmission suppression period RPc, but the present invention is not limited to this. Instead of the access parameters, parameters arbitrarily determined by the access point APc may be used. In the fourth embodiment, it is sufficient that the EHT terminal STA1 can communicate with a lower priority setting than the legacy terminal STA2 based on parameters arbitrarily determined by the access point APc during the transmission suppression period RPc.

<5> Fifth Embodiment The communication system 1 according to the fifth embodiment sets a transmission suppression period RPd by prohibiting the EHT terminal STA1 from exchanging frames during the period notified from the access point AP. Details of the communication system 1 according to the fifth embodiment will be described below.

<5-1> Configuration The hardware configuration of the communication system 1 according to the fifth embodiment is the same as the communication system 1 according to the fourth embodiment. The communication system 1 according to the fifth embodiment differs from the communication system 1 according to the fourth embodiment in the functional configuration of the wireless terminal device WTA.

(Functional configuration of wireless terminal device WTAb)
FIG. 25 is a block diagram illustrating an example of the functional configuration of the wireless terminal device WTAb included in the communication system 1 according to the fifth embodiment. As shown in FIG. 22, the wireless terminal device WTAb is a computer including, for example, an application execution unit 200, an LLC processing unit 210, a data processing unit 220, a management unit 230b, a MAC frame processing unit 240, and a wireless signal processing unit 250. Function. The management unit 230b includes, for example, link management information 231, a link control unit 232b, a beacon processing unit 233, and a transmission period management unit 234a.

The transmission period management unit 234a manages information on the transmission suppression period RPd notified from the access point APc. The transmission period management section 234a notifies the link control section 232b of the transmission suppression period RPd based on the management information of the rTWT function recorded in the link management information 231. The link control unit 232b suppresses (prohibits) frame exchange during the transmission suppression period RPd of the EHT terminal STA1 based on instructions from the transmission period management unit 234a. The transmission period management section 234a may perform timer management of the operation of the transmission suppression period RPd by the link control section 232b. The other functional configurations of the communication system 1 according to the fifth embodiment are the same as those of the communication system 1 according to the fourth embodiment.

<5-2> Frame Exchange Method FIG. 26 is a flowchart showing an example of a frame exchange method using the rTWT function of the communication system 1 according to the fifth embodiment. Below, with reference to FIG. 26, a frame exchange method using the rTWT function of the communication system 1 according to the fifth embodiment will be described, focusing on one TWT interval TI.

When the rTWT service period SP ends, a transmission suppression period RPd starts. Then, during the period α, the access point APc executes frame exchange with the legacy terminal STA2 while the EHT terminal STA1 suppresses frame exchange based on the information of the transmission suppression period RPd notified from the access point APc. (S51). Note that the access point APc can notify the EHT terminal STA1 of the period α applied to the transmission suppression period RPd by sequentially transmitting control frames. However, the period α may be set based on statistical values and notified to the EHT terminal STA1 at the time of setting up the rTWT function.

When the transmission suppression period RPd ends, the period OSP starts. Then, similarly to the first embodiment, each of the EHT terminal STA1 and the legacy terminal STA2 executes frame exchange with the access point APc under the same conditions (S14). When the period OSP ends (ends), the access point APc completes the series of processes shown in FIG. 26 and starts the process of the next rTWT service period SP.

(Specific example of frame replacement method)
FIG. 27 is a time chart showing a specific example of a frame exchange method using the rTWT function of the communication system 1 according to the fifth embodiment. FIG. 27 extracts and displays the rTWT service period SP and transmission suppression period RPd included in one TWT interval TI, and shows the respective operations of the access point APc, the EHT terminal STA1, and the legacy terminal STA2.

As shown in FIG. 27, during the rTWT service period SP, frame exchange may be performed between the EHT terminal STA1 and the access point APc, similar to the first embodiment. Furthermore, during the transmission suppression period QI set in the rTWT service period SP, the legacy terminal STA2 defers frame transmission, that is, is on standby.

When the rTWT service period SP ends, the EHT terminal STA1 spontaneously enters a transmission suppression state (for example, NAV) based on the transmission suppression period RPd notified in advance from the access point APc. On the other hand, the legacy terminal STA2 may perform frame exchange with the access point APc during the transmission suppression period RPd. Therefore, during the transmission suppression period RPd, priority is given to frame exchange between the legacy terminal STA2 and the access point APc. Other operations of the communication system 1 according to the fifth embodiment are the same as those of the communication system 1 according to the fourth embodiment.

<5-3> Effects of the fifth embodiment As explained above, in the communication system 1 according to the fifth embodiment, the EHT terminal STA1 voluntarily suppresses frame exchange after the rTWT service period SP. , sets the transmission suppression period RPd. As a result, the communication system 1 according to the fifth embodiment can maintain fairness in transmission opportunities between the wireless terminal device WTA that uses the rTWT function and the wireless terminal device WTA that does not use the rTWT function. Therefore, similarly to the first embodiment, the communication system 1 according to the fifth embodiment can suppress delays in traffic transmitted wirelessly in each of the EHT terminal STA1 and the legacy terminal STA2.

<6> Others In the above embodiment, the access point AP calculates the period α of the transmission suppression period RP based on the communication performance within the rTWT service period SP in one period of the TWT period (TWT interval TI). However, it is not limited to this. The access point AP may calculate the period α based on statistical values of communication results of a plurality of rTWT service periods SP. In the above embodiment, the case where the transmission suppression period RP is set immediately after the rTWT service period SP is illustrated, but the rTWT service period SP and the transmission suppression period RP may be separated. When the transmission suppression period RP is set based on the communication performance of the most recent rTWT service period SP, the transmission suppression period RP is set after the rTWT service period SP.

The access point AP may establish multi-links with the wireless terminal device WTA using multiple channels. Each of the access point AP and the wireless terminal device WTA may include a plurality of wireless signal processing units (STA functions) each corresponding to a plurality of channels. When a multi-link is established, a multi-link association request and a multi-link association process are executed using one of the multiple STA functions instead of the processes of S3 and S4 shown in FIG. 9, respectively. . Note that when establishing a multi-link, authentication and association processing of other links making up the multi-link may be performed using one link that is first established with the access point AP. When using multi-links, the communication system 1 can dynamically determine on which link frame exchange will be performed every rTWT service period SP. In multilink, one or more STA functions can be assigned to one traffic type. The association between traffic and STA functions is set, for example, so that the amount of traffic (amount of data) is equalized among a plurality of links forming a multilink. The present invention is not limited to this, and traffic of similar types (priority/non-priority, etc.) may be collected on a specific link forming a multi-link.

In the information communication system 1, the CPU 11 included in the access point AP and the CPU 21 included in the wireless terminal device WTA may be other circuits. For example, each of the access point AP and the wireless terminal device WTA may include an MPU (Micro Processing Unit) instead of the CPU. Each of the processes described in the embodiments may be implemented by dedicated hardware. The respective processes of the access point AP and the wireless terminal device WTA may include a mixture of processes executed by software and processes executed by hardware, or may include only one of them. The set of data processing unit 120, management unit 130, and MAC frame processing unit 140 included in the access point AP may be called a “link management unit”. Similarly, the set of data processing unit 220, management unit 230, and MAC frame processing unit 240 included in the wireless terminal device WTA may be referred to as a “link management unit”.

In the above embodiment, the flowchart used to explain the operation is just an example. For each operation described in the embodiment, the order of processing may be changed to the extent possible, or other processing may be added. For example, the link setup method described in the first embodiment is just an example. Furthermore, the format of the radio frame described in the first embodiment is just an example. In the information communication system 1, other formats may be used as long as they can perform the operations described in the embodiments. A wireless communication standard different from the IEEE802.11 standard may be used for wireless communication between the access point AP and the wireless terminal device WTA.

Note that the present invention is not limited to the above-described embodiments, and can be variously modified at the implementation stage without departing from the gist thereof. Moreover, each embodiment may be implemented in combination as appropriate, and in that case, the combined effect can be obtained. Furthermore, the embodiments described above include various inventions, and various inventions can be extracted by combinations selected from the plurality of disclosed constituent features. For example, if a problem can be solved and an effect can be obtained even if some constituent features are deleted from all the constituent features shown in the embodiment, the configuration from which these constituent features are deleted can be extracted as an invention.

1...Communication system AP...Access point 11...CPU
12...ROM
13...RAM
14... Wireless communication module 15... Wired communication module 110... LLC processing unit 120... Data processing unit 130... Management unit 131... Link management information 132... Link control unit 133... Beacon management unit 134... Transmission period management unit 135... Transmission prohibited frame Generation unit 136... Transmission prohibited terminal determination unit 137... rTWT setting notification unit 140... MAC frame processing unit 150... Radio signal processing unit 151... Classification unit 152... Queue 153... Carrier sense execution unit 154... Internal collision management unit WTA... Wireless terminal Device 21...CPU
22...ROM
23...RAM
24...Wireless communication module 25...Display 26...Storage 200...Application execution unit 210...LLC processing unit 220...Data processing unit 230...Management unit 231...Link management information 232...Link control unit 233...Beacon processing unit 234...Transmission period management Unit 240...MAC frame processing unit 250...Radio signal processing unit STA1...EHT terminal STA2...Legacy terminal

Claims

a first wireless signal processing unit;
A first link with the first wireless terminal device and a second link with the second wireless terminal device are established using the first wireless signal processing unit, and a service period is established in a first cycle. a first management department that sets up the
The first management unit provides an opportunity to transmit data to the first wireless terminal device and suppresses or prohibits data transmission by the second wireless terminal device within the service period, and setting a transmission suppression period for suppressing or prohibiting data transmission by the first wireless terminal device outside the period;
access point.
The first management unit uses the wireless signal processing unit to transmit a first frame instructing prohibition of data transmission during the transmission suppression period to the first wireless terminal device at the start of the transmission suppression period. send to,
The access point according to claim 1.
The first management unit is configured not to transmit a CTS (Clear To Send) in response to an RTS (Request To Send) received from the first wireless terminal device during the transmission suppression period.
The access point according to claim 1.
The first management unit determines the length of the transmission suppression period based on the length of the service period or the length of a frame exchange period with the first wireless terminal device executed within the service period. setting the
The access point according to claim 1.
The first management unit transmits a second frame including information about the transmission suppression period to the first wireless terminal device using the first radio signal processing unit before the start of the transmission suppression period. Send,
The access point according to claim 1.
The access point according to claim 5,
The first wireless terminal device,
The first wireless terminal device includes a second wireless signal processing unit and a second wireless signal processing unit that uses the second wireless signal processing unit to establish the first link and manages a state of the first link. 2 management departments,
The second management unit determines the access parameters of the first link during the transmission suppression period based on the information included in the second frame received by the first wireless terminal device. setting lower priority than the access parameter of the first link outside the period and outside the transmission suppression period;
Communications system.
The access point according to claim 5,
The first wireless terminal device,
The first wireless terminal device includes a second wireless signal processing unit and a second wireless signal processing unit that uses the second wireless signal processing unit to establish the first link and manages a state of the first link. 2 management departments,
The second management unit controls the transmission of data using the first link during the transmission suppression period based on the information included in the second frame received by the first wireless terminal device. prohibit,
Communications system.
a wireless signal processing unit;
a management unit that establishes a link with an access point using the wireless signal processing unit and manages the state of the link,
The management department is
receiving first information including periodic service period information from the access point, and transmitting data using the link during the service period;
receiving second information including information on a transmission suppression period outside the service period from the access point, and suppressing or prohibiting data transmission using the link during the transmission suppression period;
Wireless terminal equipment.
The management unit sets an access parameter of the link during the transmission suppression period to a lower priority than an access parameter of the link outside the service period and outside the transmission suppression period, based on the second information.
The wireless terminal device according to claim 8.
The management unit prohibits data transmission using the link during the transmission suppression period based on the second information.
The wireless terminal device according to claim 8.