WO2025243470A1 - Access point and terminal - Google Patents

Abstract

An access point according to one embodiment comprises a wireless communication unit and a management unit. The management unit enables data transmission between a plurality of terminals that are wirelessly connected to the wireless communication unit, and when a first access point, which is one among access points other than an own station, transmits low-latency traffic to and from a wirelessly connected terminal, the management unit causes data to be transmitted between the plurality of terminals while avoiding a period in which the low-latency traffic is transmitted between the first access point and said terminal.

Description

Access points and terminals

The embodiment relates to an access point and a terminal.

In a wireless communication network such as a wireless LAN (local area network), for example, an access point (AP) and a terminal such as a non-AP station (STA) are wirelessly connected. In a wireless communication network, a terminal transmits data wirelessly between APs located in the communication area of the terminal. In addition, a wireless communication network also allows multiple terminals to communicate with each other using P2P (peer-to-peer) communication, transmitting data without using an AP.

The IEEE 802.11be standard is scheduled to specify the TXS (triggered TXOP sharing) function as an extension of the TXOP sharing function. With the TXS function, an AP allocates a portion of its TXOP (channel occupancy period), a transmission opportunity acquired through carrier sensing, to a terminal located in its communication area and shares the acquired TXOP with wirelessly connected terminals. Furthermore, with the TXS function, a terminal that has been allocated a portion of its TXOP by the AP as its communication period can conduct P2P communication with other terminals during the communication period allocated by the AP, and can allocate the communication period allocated by the AP to data transmission with other terminals via P2P communication. This allows terminals to conduct P2P communication with other terminals without setting up a link.

As mentioned above, in a situation where P2P communication is taking place between multiple terminals, for example, if another communication station transmits data near a terminal conducting P2P communication, the data transmission via P2P communication may interfere with the data transmission by the other communication station. In particular, when a communication station other than the terminal conducting P2P communication transmits low-latency traffic, it is necessary to effectively suppress interference of data transmission via P2P communication with the transmission of low-latency traffic, in order to ensure the low latency of the low-latency traffic.

IEEE P802.11-23/294r1 “Channel Usage Enhancement for P2P in UHR”, May, 2023, “https://mentor.ieee.org/802.11/dcn/23/11-23-0294”

The object of the present invention is to provide an access point and terminal that effectively suppress interference of data transmission via P2P communication with low-latency traffic transmission by a communication station other than the terminal performing P2P communication.

In one embodiment of the present invention, an access point includes a wireless communication unit and a management unit. The management unit enables data transmission between multiple terminals wirelessly connected to the wireless communication unit, and when a first access point, which is one of the access points other than the access point itself, transmits low-latency traffic between the first access point and the terminal, the management unit allows data transmission between the multiple terminals while avoiding the period during which low-latency traffic is transmitted between the first access point and the terminal.

The present invention provides an access point and terminal that effectively suppress interference of data transmission via P2P communication with low-latency traffic transmission by a communication station other than the terminal performing P2P communication.

FIG. 1 is a block diagram illustrating an example of a configuration of a communication system according to an embodiment. FIG. 2 is a block diagram illustrating an example of a hardware configuration of a sharing AP according to the embodiment. FIG. 3 is a block diagram illustrating an example of a hardware configuration of a shared AP according to the embodiment. FIG. 4 is a block diagram illustrating an example of a hardware configuration of a terminal according to the embodiment. FIG. 5 is a block diagram illustrating an example of the functional configuration of a sharing AP according to the embodiment. FIG. 6 is a block diagram illustrating an example of the functional configuration of a shared AP according to the embodiment. FIG. 7 is a block diagram illustrating an example of a functional configuration of a terminal according to the embodiment. FIG. 8 is a schematic diagram illustrating an example of a format of a TXS trigger frame generated by a shared AP in an embodiment. Figure 9 is a flowchart showing an example of processing performed by an AP to which multiple terminals performing P2P communication are wirelessly connected when P2P communication is performed between multiple terminals and low-latency traffic is transmitted between the AP and a terminal in an embodiment. Figure 10 is a sequence diagram showing an example of the order of data transmission when P2P communication is performed between multiple terminals and low-latency traffic is transmitted between a terminal and a shared AP in a communication system related to an embodiment. Figure 11 is a sequence diagram showing another example of the order of data transmission when P2P communication is performed between multiple terminals and low-latency traffic is transmitted between a terminal and a shared AP in a communication system related to an embodiment, which is different from Figure 10.

The following describes the embodiments with reference to the drawings. In the following description, components with the same functions and configurations are designated by the same reference numerals.

FIG. 1 is a block diagram showing an example of the configuration of a communication system according to an embodiment. As shown in FIG. 1, communication system 1 includes a sharing AP 10 and shared APs 20-1, 20-2, and 20-3 as access points (APs), and terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B as non-AP stations (STAs). Each of sharing AP 10, shared APs 20-1, 20-2, and 20-3, and terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B functions as a single communication station in communication system 1. Furthermore, a wireless network such as a wireless LAN is formed in communication system 1.

In the following description, the sharing AP 10 will also be referred to as AP0, and the shared APs 20-1, 20-2, and 20-3 will also be referred to as AP1, AP2, and AP3, respectively. Terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B will also be referred to as STA1A, STA1B, STA2, STA3A, and STA3B, respectively. The shared APs 20-1, 20-2, and 20-3 have the same configuration as each other. Therefore, when no particular distinction is required, the shared APs 20-1, 20-2, and 20-3 will also be referred to simply as the shared AP 20. The terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B have the same configuration as each other. For this reason, when no particular distinction is needed, terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B will also be referred to simply as terminal 30.

In the communication system 1, the sharing AP 10 is connected to the network 40 and can communicate with a server (not shown) on the network 40 via wired or wireless connections. The sharing AP 10 can also communicate with each of the shared APs 20 via wired or wireless connections.

The shared APs 20 are installed in locations physically separated from one another, and have different communication areas. The communication area of each shared AP 20 may partially overlap with that of any of the shared APs 20 other than the local station, or there may be no overlapping communication area with any of the shared APs 20 other than the local station. Each shared AP 20 can wirelessly connect to each of the terminals 30 located in its communication area. Each shared AP 20 communicates wirelessly with each of the wirelessly connected terminals 30, for example, in accordance with the IEEE 802.11 standard.

Each of the terminals 30 is a wireless terminal, such as a smartphone, a PC (personal computer), or an IoT (internet of things) device. In the example of FIG. 1, each of the terminals 30-1A and 30-1B is wirelessly connected to the shared AP 20-1 and is capable of wireless communication with the shared AP 20-1. Furthermore, the terminal 30-2 is wirelessly connected to the shared AP 20-2 and is capable of wireless communication with the shared AP 20-2. Furthermore, each of the terminals 30-3A and 30-3B is wirelessly connected to the shared AP 20-3 and is capable of wireless communication with the shared AP 20-3.

Furthermore, in the communication system 1, data can be transmitted between multiple terminals 30 wirelessly connected to a common shared AP 20 without passing through an AP, including the sharing AP 10 and the shared AP 20. Data transmission that occurs directly between multiple terminals 30 is also called "P2P (peer to peer) communication." In the example shown in Figure 1, P2P communication can be performed between terminals 30-1A and 30-1B that are wirelessly connected to a common shared AP 20-1. Furthermore, P2P communication can be performed between terminals 30-3A and 30-3B that are wirelessly connected to a common shared AP 20-3.

In one example, one or more terminals 30 perform multi-link communication using multiple links (channels). In this case, the terminal 30 performing multi-link communication has a non-AP MLD as a multi-link device (MLD) and multiple affiliated STAs (stations). In the terminal 30 performing multi-link communication, one link is set for each of the multiple affiliated STAs, and each affiliated STA is wirelessly connected to either the shared AP 20 or a terminal 30 other than the terminal itself via a corresponding one of the multiple links. In the terminal 30 performing multi-link communication, each of the multiple affiliated STAs may share a connection destination with one of the other affiliated STAs, or may have a connection destination that is different from that of any of the other affiliated STAs.

In the communication system 1, each of the terminals 30 can communicate with the sharing AP 10 via one or more of the shared APs 20 that are capable of wireless communication. Therefore, each of the terminals 30 can communicate with a server on the network 40 via one or more of the corresponding shared APs 20 and the sharing AP 10. In the example shown in FIG. 1, each of the terminals 30-1A and 30-1B is connected to the sharing AP 10 via the shared AP 20-1, the terminal 30-2 is connected to the sharing AP 10 via the shared AP 20-2, and the terminals 30-3A and 30-3B are connected to the sharing AP 10 via the shared AP 20-3.

The connection method between each of the terminals 30 and the sharing AP 10 as described above is also referred to as the "multi-AP connection method." Furthermore, each of the shared APs 20 is also referred to as an "access point belonging" to the sharing AP 10 in the multi-AP connection method. Therefore, the sharing AP 10 is also referred to as the "associated AP," and each of the shared APs 20 is also referred to as the "associated AP." Furthermore, each shared AP 20 refers to the terminal 30 wirelessly connected to itself as a "subordinate terminal." Furthermore, in the multi-AP connection method, one terminal 30 may be wirelessly connected to multiple shared APs 20. In one example, in communication system 1, terminal 30-2 is wirelessly connected to both shared APs 20-1 and 20-2.

Each of the sharing AP 10, shared AP 20, and terminal 30 has wireless communication functions based on, for example, the OSI (open systems interconnection) reference model. In the OSI reference model, wireless communication functions are divided into seven layers (Layer 1: physical layer, Layer 2: data link layer, Layer 3: network layer, Layer 4: transport layer, Layer 5: session layer, Layer 6: presentation layer, and Layer 7: application layer). The data link layer includes an LLC (logical link control) sublayer and a MAC (media access control) sublayer.

FIG. 2 is a block diagram showing an example of the hardware configuration of a sharing AP according to an embodiment. FIG. 2 shows an example in which the sharing AP 10 communicates via wired communication with a server on the network 40, and also communicates wirelessly with each of the shared APs 20. As shown in FIG. 2, the sharing AP 10 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 a processing circuit that controls the overall operation of the sharing AP 10. The ROM 12 is, for example, a non-volatile semiconductor memory. The ROM 12 stores programs and data for controlling the sharing AP 10. The RAM 13 is, for example, a volatile semiconductor memory. The RAM 13 is used as a working area for the CPU 11. The wireless communication module 14 is a circuit used to send and receive data via wireless signals. The wireless communication module 14 is connected to an antenna. The wired communication module 15 is a circuit used to send and receive data via wired signals. In the example shown in Figure 2, the wireless communication module 14 can be connected (wirelessly connected) to the shared APs 20-1, 20-2, and 20-3. The wired communication module 15 can then be connected to the network 40.

Note that when the sharing AP 10 communicates wirelessly with a server on the network 40 and also communicates wired with each of the shared APs 20, the wireless communication module 14 can be connected to the network 40, and the wired communication module 15 can be connected (wirelessly) to the shared APs 20-1, 20-2, and 20-3. Also, when the sharing AP 10 communicates wired with both the server on the network 40 and the shared AP 20, the sharing AP 10 does not have a wireless communication module 14. In this case, the wired communication module 15 can be connected to the network 40 and can be connected (wired) to the shared APs 20-1, 20-2, and 20-3. Also, when the sharing AP 10 communicates wirelessly with both the server on the network 40 and the shared AP 20, the sharing AP 10 does not have a wired communication module 15. In this case, the wireless communication module 14 can be connected to the network 40 and can also be connected (wirelessly) to the shared APs 20-1, 20-2, and 20-3.

FIG. 3 is a block diagram showing an example of the hardware configuration of a shared AP according to an embodiment. FIG. 3 shows an example of a case where a shared AP 20 communicates wirelessly with a sharing AP 10. In one example, each of the shared APs 20-1, 20-2, and 20-3 has the same hardware configuration as the example shown in FIG. 3. As shown in FIG. 3, the shared AP 20 includes, for example, a CPU 21, a ROM 22, a RAM 23, and a wireless communication module 24.

The CPU 21 is a processing circuit that controls the overall operation of the shared AP 20. The ROM 22 is, for example, a non-volatile semiconductor memory. The ROM 22 stores programs and data for controlling the shared AP 20. The RAM 23 is, for example, a volatile semiconductor memory. The RAM 23 is used as a working area for the CPU 21. The wireless communication module 24 is a circuit used to send and receive data via wireless signals. The wireless communication module 24 is connected to an antenna. The wireless communication module 24 can be connected (wirelessly connected) to the sharing AP 10 and to terminals 30 located in the communication area.

If the shared AP 20 communicates with the sharing AP 10 via a wired connection, the shared AP 20 is further provided with a wired communication module (not shown). In this case, the wireless communication module 24 can be connected to a terminal 30 located in the communication area, and the wired communication module can be connected (wired) to the sharing AP 10.

FIG. 4 is a block diagram showing an example of the hardware configuration of a terminal according to an embodiment. In one example, each of terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B has a hardware configuration similar to the example shown in FIG. 4. As shown in FIG. 4, terminal 30 includes, for example, a CPU 31, ROM 32, RAM 33, a wireless communication module 34, a display 35, and storage 36.

The CPU 31 is a processing circuit that controls the overall operation of the terminal 30. The ROM 32 is, for example, a non-volatile semiconductor memory. The ROM 32 stores programs and data for controlling the terminal 30. The RAM 33 is, for example, a volatile semiconductor memory. The RAM 33 is used as a working area for the CPU 31. The wireless communication module 34 is a circuit used to send and receive data via wireless signals. The wireless communication module 34 is connected to an antenna. The wireless communication module 34 can be connected (wirelessly connected) to one or more corresponding shared APs 20. The display 35 is, for example, an LCD (liquid crystal display) or an EL (electro-luminescence) display. The display 35 displays a GUI (graphical user interface) corresponding to application software, etc. The storage 36 is a non-volatile storage device. The storage 36 stores the system software, etc. of the terminal 30.

FIG. 5 is a block diagram showing an example of the functional configuration of a sharing AP according to an embodiment. The following explanation using FIG. 5 will mainly describe the functional configuration of the sharing AP 10 when the sharing AP 10 communicates wirelessly with each of the shared APs 20. As shown in FIG. 5, the sharing AP 10 functions as a computer comprising an upper layer processing unit 110, a management unit 120, a frame processing unit 130, and a transmission/reception unit 140. The upper layer processing unit 110 is a functional block that executes processing corresponding to the LLC sublayer of the second layer and layers 3 to 7. The management unit 120 and frame processing unit 130 are functional blocks that execute processing corresponding to the MAC sublayer of the second layer. The transmission/reception unit 140 is a functional block that executes processing corresponding to the MAC sublayer of the second layer and layer 1. The management unit 120 also includes a transmission period management unit 121, which performs part of the processing performed by the management unit 120.

The upper layer processing unit 110 generates an LLC packet as a data unit containing data, for example, by adding a DSAP (destination service access point) header or an SSAP (source service access point) header to data received from the network 40. The upper layer processing unit 110 then inputs the generated LLC packet to the frame processing unit 130. The upper layer processing unit 110 also extracts data from the LLC packet input from the frame processing unit 130. The upper layer processing unit 110 then transmits the extracted data to the network 40.

The management unit 120 manages the connections (logical connections) between the sharing AP 10 and each of the terminals 30 in the multi-AP connection method. Therefore, the management unit 120 manages the wireless connections between each of the shared APs 20 to which it belongs and the terminals 30 located in the communication area. Furthermore, when P2P communication is performed between multiple terminals 30 wirelessly connected to the shared AP 20, the management unit 120 manages the wireless connections between the multiple terminals 30.

The management unit 120 performs management based on information about the access points (sharing AP 10 and shared AP 20) used in the multi-AP connection method, and information about the terminals 30 (e.g., terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B) connected to the sharing AP 10 using the multi-AP connection method. The information about the access points indicates information about each access point used, such as the identifier, frequency band or channel used, and operational parameters. The information about the terminals 30 indicates information about each terminal 30 connected to the sharing AP 10, such as the identifier of that terminal 30 and the identifier of the shared AP 20 through which the connection to the sharing AP 10 is made. Furthermore, when P2P communication is taking place between multiple terminals 30 wirelessly connected to the shared AP 20, the management unit 120 acquires information about the terminals 30 performing P2P communication and manages the wireless connection between the terminals 30 based on the acquired information.

The management unit 120 inputs management information and control information to the frame processing unit 130. The management information input to the frame processing unit 130 includes management information to be notified to either the shared AP 20 or the terminal 30, and the control information input to the frame processing unit 130 includes control information related to control of the operation of either the shared AP 20 or the terminal 30. In addition, management information and control information are input to the management unit 120 from the frame processing unit 130. The management information input to the management unit 120 includes management information notified from either the shared AP 20 or the terminal 30, and the control information input to the management unit 120 includes control information related to control of the operation of either the sharing AP 10, the shared AP 20, or the terminal 30.

The frame processing unit 130 adds a MAC header to LLC packets, which are data units input from the upper layer processing unit 110, to generate data frames as MAC frames. The frame processing unit 130 also generates management frames containing management information input from the management unit 120, and control frames containing control information input from the management unit 120, as MAC frames. The frame processing unit 130 then outputs the generated MAC frames (data frames, management frames, and control frames) to the transceiver unit 140. The frame processing unit 130 also extracts LLC packets, management information, or control information from the MAC frames (data frames, management frames, and control frames) input from the transceiver unit 140. The frame processing unit 130 then outputs the extracted LLC packets to the upper layer processing unit 110, and inputs the extracted management information and control information to the management unit 120. Management frames include, for example, action frames, beacon frames, and probe response frames, while control frames include, for example, trigger frames.

The transceiver 140 transmits and receives data, management information, control information, etc., via wireless communication to each of the shared APs 20 to which it belongs. The transceiver 140 generates wireless frames by adding preambles, etc., to MAC frames (data frames, management frames, and control frames) input from the frame processing unit 130, and converts the generated wireless frames into wireless signals. The transceiver 140 then transmits (radiates) the converted wireless signals to one of the shared APs 20 via an antenna. The process of converting wireless frames into wireless signals includes, for example, convolutional coding, interleaving, subcarrier modulation, inverse fast Fourier transform, OFDM (orthogonal frequency division multiplexing) modulation, and frequency conversion.

Furthermore, the transceiver 140 converts wireless signals received from one of the shared APs 20 via the antenna into wireless frames. The process of converting wireless signals into wireless frames includes, for example, frequency conversion, OFDM demodulation, fast Fourier transform, subcarrier demodulation, deinterleaving, and Viterbi decoding. Each transceiver 140 extracts a MAC frame from the converted wireless frame and outputs the extracted MAC frame to the frame processor 130. In one example, multiple shared APs (associated APs) 20 belonging to a sharing AP 10 transmit and receive wireless signals to and from the transceiver 140 of the sharing AP 10 using different frequency bands or channels.

The management unit 120 works in cooperation with the shared AP 20 and terminal 30 to which it belongs, to allocate (map) traffic transmitted and received between the sharing AP 10 and terminal 30. This allows traffic such as data transmitted from the sharing AP 10 to be allocated to the shared AP 20 to which it belongs. Based on the traffic allocation results, the management unit 120 instructs the frame processing unit 130 on the destination of the traffic. The frame processing unit 130 then causes the transmission/reception unit 140 to transmit the traffic to the shared AP 20 corresponding to the instruction from the management unit 120.

When the sharing AP 10 communicates with each of the shared APs 20 via wired communication, a data and information processing unit is provided instead of the frame processing unit 130. The data and information processing unit outputs LLC packets, which are data units input from the upper layer processing unit 110, to the transceiver unit 140, and outputs LLC packets input from the transceiver unit 140 to the upper layer processing unit 110. The data and information processing unit also outputs management information and control information input from the management unit 120 to the transceiver unit 140, and inputs management information and control information input from the transceiver unit 140 to the management unit 120.

Furthermore, when the sharing AP 10 communicates with each of the shared APs 20 via a wired network, the transmission/reception unit 140 is connected to each of the shared APs 20 to which it belongs via a wired network, and transmits and receives data, management information, control information, etc. to and from each of the shared APs 20 via the wired network. The transmission/reception unit 140 is configured from a network interface for the wired network.

FIG. 6 is a block diagram showing an example of the functional configuration of a shared AP according to an embodiment. The following explanation using FIG. 6 will mainly describe the functional configuration of the shared AP 20 when the shared AP 20 communicates wirelessly with the sharing AP 10. In one example, each of the shared APs 20-1, 20-2, and 20-3 has the same functional configuration as the example shown in FIG. 6. As shown in FIG. 6, the shared AP 20 functions as a computer equipped with a management unit 210, a frame processing unit 220, a transmission/reception unit 230, and a wireless communication unit 240. The management unit 210 and frame processing unit 220 are functional blocks that perform processing corresponding to the MAC sublayer of the second layer. The transmission/reception unit 230 and the wireless communication unit 240 are functional blocks that perform processing corresponding to the MAC sublayer of the second layer and the first layer. The management unit 210 also includes a TXS management unit 211 and a transmission period management unit 212, and the TXS management unit 211 and the transmission period management unit 212 each perform part of the processing of the management unit 210.

In the multi-AP connection method, the management unit 210 manages wireless connections between the local station and terminals 30 located in the communication area. Furthermore, when P2P communication is performed between multiple terminals 30 wirelessly connected to the local station, the management unit 210 manages the wireless connections between the multiple terminals 30. Furthermore, the management unit 210 performs management based on information about the terminals 30 wirelessly connected to the local station's shared AP 20 in the multi-AP connection method. The information about the terminals 30 indicates, for example, information about identifiers for each terminal 30 wirelessly connected to the local station. Furthermore, when P2P communication is performed between multiple terminals 30 wirelessly connected to the local station, the management unit 210 acquires information about the terminals 30 performing P2P communication, and manages the wireless connections between the terminals 30 based on the acquired information.

The management unit 210 inputs management information and control information to the frame processing unit 220. The management information input to the frame processing unit 220 includes management information to be notified to either the sharing AP 10, a shared AP 20 other than the local station, or a terminal 30, and the control information input to the frame processing unit 220 includes control information related to control of the operation of either the sharing AP 10, a shared AP 20 other than the local station, or a terminal 30. Furthermore, management information and control information are input to the management unit 210 from the frame processing unit 220. The management information input to the management unit 210 includes management information to be notified to either the shared AP 20 of the local station or a terminal 30 wirelessly connected to the local station, and the control information input to the management unit 210 includes control information related to control of the operation of either the shared AP 20 of the local station or a terminal 30 wirelessly connected to the local station.

MAC frames (data frames, management frames, and control frames) are input to the frame processing unit 220 from the transceiver unit 230 and the wireless communication unit 240. If the MAC frame from the transceiver unit 230 contains data, management information, or control information to be transmitted to the wirelessly connected terminal 30, the frame processing unit 220 outputs the MAC frame input from the transceiver unit 230 to the wireless communication unit 240. If the MAC frame from the wireless communication unit 240 contains data, management information, or control information to be transmitted to the sharing AP 10, the frame processing unit 220 outputs the MAC frame input from the wireless communication unit 240 to the transceiver unit 230. Furthermore, if the MAC frame from either the transceiver unit 230 or the wireless communication unit 240 contains management information or control information for the local station, the frame processing unit 220 extracts the management information or control information from the input MAC frame. The frame processing unit 220 then outputs the extracted management information and control information to the management unit 210.

Furthermore, the frame processing unit 220 generates, as MAC frames, a management frame including management information input from the management unit 210, and a control frame including control information input from the management unit 210. If the generated MAC frame includes either management information or control information to be transmitted to the wirelessly connected terminal 30, the frame processing unit 220 outputs the generated MAC frame to the wireless communication unit 240. If the generated MAC frame includes either management information or control information to be transmitted to the sharing AP 10, the frame processing unit 220 outputs the generated MAC frame to the transceiver unit 230.

The transmitter/receiver unit 230 transmits and receives data, management information, control information, etc. to and from the sharing AP 10 via wireless communication. The wireless communication unit 240 also transmits and receives data, management information, control information, etc. to and from the terminal 30 that is wirelessly connected to the local station via wireless communication. The transmitter/receiver unit 230 and the wireless communication unit 240 each add a preamble, etc. to the MAC frame (data frame, management frame, or control frame) input from the frame processing unit 220 to generate a wireless frame and convert the generated wireless frame into a wireless signal. The transmitter/receiver unit 230 transmits (radiates) the converted wireless signal to the sharing AP 10 via the antenna, and the wireless communication unit 240 transmits (radiates) the converted wireless signal to the terminal 30 via the antenna. The conversion process from a wireless frame to a wireless signal is performed as described above.

Furthermore, the transceiver unit 230 converts wireless signals received from the sharing AP 10 via the antenna into wireless frames, and the wireless communication unit 240 converts wireless signals received from the terminal 30 via the antenna into wireless frames. The conversion process from wireless signals to wireless frames is performed as described above. The transceiver unit 230 and the wireless communication unit 240 each extract MAC frames from the converted wireless frames and output the extracted MAC frames to the frame processing unit 220.

Here, it is preferable that the transceiver unit 230 transmits and receives using a frequency band or channel different from that of the wireless communication unit 240. In one example, the transceiver unit 230 may not be provided. In this case, the shared AP 20 performs wireless communication with the sharing AP 10 and each of the wirelessly connected terminals 30 via the wireless communication unit 240.

In the multi-AP connection method, the transmission/reception unit 230 receives instructions from the sharing AP 10 regarding the transmission of traffic (data) between itself and the terminal 30 that is wirelessly connected to itself. The management unit 210 controls data transmission (transmission and reception of data) between itself and the terminal 30 that is wirelessly connected to its shared AP 20 in accordance with the instructions from the sharing AP 10.

When the shared AP 20 communicates with the sharing AP 10 via a wired network, the transceiver 230 is connected to the sharing AP 10 via a wired network, and transmits and receives data, management information, control information, etc. to and from the sharing AP 10 via the wired network. In this case, the transceiver 230 is configured from a network interface for the wired network. The transceiver 230 then inputs the LLC packets, management information, and control information received from the sharing AP 10 to the frame processing unit 220.

The frame processing unit 220 adds a MAC header to the LLC packet, which is a data unit input from the transceiver unit 230, and generates a data frame as a MAC frame. The frame processing unit 220 then inputs the generated data frame to the wireless communication unit 240. When transmitting management information and control information from the transceiver unit 230 to a wirelessly connected terminal 30, the frame processing unit 220 generates a management frame containing management information and a control frame containing control information as MAC frames, and outputs the generated MAC frames to the wireless communication unit 240. When management information and control information for the local station is input from the transceiver unit 230, the frame processing unit 220 outputs the input management information and control information to the management unit 210.

When the shared AP 20 communicates with the sharing AP 10 via a wired connection, the frame processing unit 220 extracts either an LLC packet, management information, or control information from the MAC frame (data frame, management frame, or control frame) from the wireless communication unit 240. The frame processing unit 220 then outputs the extracted LLC packet to the transceiver unit 230. When transmitting the extracted management information and control information to the sharing AP 10, the frame processing unit 220 outputs the management information and control information to the transceiver unit 230. When extracting management information and control information for the local station, the frame processing unit 220 outputs the management information and control information to the management unit 210. When transmitting management information and control information input from the management unit 210 to the sharing AP 10, the frame processing unit 220 outputs the management information and control information from the management unit 210 to the transceiver unit 230.

FIG. 7 is a block diagram showing an example of the functional configuration of a terminal according to an embodiment. In one example, each of terminals 30-1A, 30-1B, 30-2, 30-3A, and 30-3B has the same functional configuration as the example shown in FIG. 7. As shown in FIG. 7, terminal 30 functions as a computer equipped with an upper layer processing unit 310, a management unit 320, a frame processing unit 330, and a wireless communication unit 340. The upper layer processing unit 310 is a functional block that executes processing corresponding to the LLC sublayer of the second layer and layers 3 to 7. The management unit 320 and frame processing unit 330 are functional blocks that execute processing corresponding to the MAC sublayer of the second layer. The wireless communication unit 340 is a functional block that executes processing corresponding to the MAC sublayer of the second layer and layer 1. The management unit 320 also includes a transmission period adjustment unit 321, which performs part of the processing performed by the management unit 320.

The upper layer processing unit 310 generates LLC packets by adding DSAP headers, SSAP headers, etc. to the data. The upper layer processing unit 310 then outputs the generated LLC packets to the frame processing unit 330. The upper layer processing unit 310 also extracts data from the LLC packets input from the frame processing unit 330. The upper layer processing unit 310 then executes an application based on the extracted data. For example, the upper layer processing unit 310 can display application information on the display 35. The upper layer processing unit 310 can also operate based on operations on the input interface.

The management unit 320 manages the connection (logical wireless connection) between the sharing AP 10 and the local terminal 30 in the multi-AP connection method. Therefore, the management unit 320 manages the wireless connection between the local station and the shared AP 20 in whose communication area the local station is located. Furthermore, when the local station performs P2P communication with another terminal 30, the management unit 320 manages the wireless connection between the local station and the terminal 30 performing P2P communication. The management unit 320 performs management based on information about the shared AP 20 that is the wireless connection destination of the local station's terminal 30 in the multi-AP connection method. The information about the shared AP 20 indicates, for example, information about the identifier for each shared AP 20 that is the connection destination of the local station. When the local station performs P2P communication with another terminal 30, the management unit 320 acquires information about the terminal 30 that is the P2P communication destination, and manages the wireless connection between the local station and the terminal 30 performing P2P communication based on the acquired information.

The management unit 320 inputs management information and control information to the frame processing unit 330. The management information input to the frame processing unit 330 includes management information to be notified to either the sharing AP 10, the shared AP 20, or a terminal 30 other than the local station, and the control information input to the frame processing unit 330 includes control information related to controlling the operation of either the sharing AP 10, the shared AP 20, or a terminal 30 other than the local station. In addition, management information and control information are input to the management unit 320 from the frame processing unit 330. The management information input to the management unit 320 includes management information to be notified to the local station, and the control information input to the management unit 320 includes control information related to controlling the operation of the local station.

The frame processing unit 330 adds a MAC header to the LLC packet input from the upper layer processing unit 310 to generate a data frame as a MAC frame. The frame processing unit 330 also generates a management frame containing management information input from the management unit 320, and a control frame containing control information input from the management unit 320, as MAC frames. The frame processing unit 330 then outputs the generated MAC frames to the wireless communication unit 340. The frame processing unit 330 also extracts any of the LLC packet, notification information, control information, etc. from the MAC frame input from the wireless communication unit 340 (data frame, management frame, and control frame). The frame processing unit 330 then outputs the extracted LLC packet to the upper layer processing unit 310, and outputs the extracted notification information and control information to the management unit 320.

The wireless communication unit 340 generates a wireless frame by adding a preamble and the like to the MAC frame input from the frame processing unit 330. The wireless communication unit 340 then converts the generated wireless frame into a wireless signal and transmits (radiates) the converted wireless signal via an antenna to the shared AP 20 to which it is connected. The conversion process from wireless frame to wireless signal is performed as described above. In P2P communication between the wireless communication unit 340 and another terminal 30, the wireless communication unit 340 transmits a wireless signal to the terminal 30 with which it is performing P2P communication.

The wireless communication unit 340 also converts wireless signals received via an antenna from the shared AP 20, which is the destination of the wireless connection, into wireless frames. The conversion process from wireless signals to wireless frames is performed as described above. The wireless communication unit 340 extracts MAC frames from the converted wireless frames and outputs the extracted MAC frames to the frame processing unit 330. In P2P communication between the wireless communication unit 340 and another terminal 30, the wireless communication unit 340 receives wireless signals from the terminal 30 performing P2P communication.

Note that while the example in Figure 7 shows a case where only one wireless communication unit 340 is provided, this is not limited to this. In one example, one or more of the terminals 30 perform multi-link communication, and the terminal 30 performing multi-link communication is provided with multiple wireless communication units 340 as multiple affiliated STAs. In this case, each of the multiple wireless communication units 340 in the terminal 30 is wirelessly connected to one of the shared APs 20 (and other terminals 30) via a corresponding one of the multiple links. Furthermore, in the terminal 30, the management unit 320 and frame processing unit 330 function as a non-AP MLD, and the management unit 320 manages the wireless connection with the connection destination for each of the multiple wireless communication units 340.

In this embodiment, the shared AP 20 and each of the terminals 30 wirelessly connected to the shared AP 20 are capable of performing communication operations based on the TXS (triggered TXOP sharing) function, which is an extension of the TXOP sharing function. Each shared AP 20 uses the TXS function to allocate a portion of the TXOP (channel occupancy period), which is a transmission opportunity acquired by carrier sensing, to terminals located in its communication area. As a result, each shared AP 20 shares the acquired TXOP with the terminals wirelessly connected to it.

Furthermore, a terminal 30 that has been assigned a portion of its TXOP by the shared AP 20 as a communication period can use the TXS function to allocate the communication period (part of the TXOP) assigned by the shared AP 20 to P2P communication with another terminal 30 other than its own station. This allows the terminal 30 that has been assigned a communication period by the shared AP 20 to transmit data with another terminal 30 via P2P communication during the assigned communication period, enabling P2P communication with another terminal without setting up a link. In P2P communication based on the TXS function, a terminal 30 transmits data with another terminal 30 that is wirelessly connected to a common shared AP 20. In the example of Figure 1, P2P communication based on the TXS function is performed between multiple terminals 30-1A and 30-1B that are wirelessly connected to a common shared AP 20-1, and P2P communication is performed between terminals 30-3A and 30-3B that are wirelessly connected to a common shared AP 20-3.

In each shared AP 20, the TXS management unit 211 of the management unit 210 manages TXS information as information related to the TXS function. The TXS information includes, for example, the identifier of the terminal 30 to which part of the acquired TXOP is allocated as a communication period, and information regarding the duration and time range of the communication period allocated to the terminal 30. Furthermore, if the terminal 30 that allocates the communication period (part of the TXOP) performs P2P communication with another terminal 30 during the communication period, the TXS information includes information regarding the identifiers of the multiple terminals 30 that perform P2P communication. The TXS information also includes information regarding constraints on P2P communication, such as information regarding the time range during which P2P communication can be performed.

In the shared AP 20, the TXS management unit 211 outputs the TXS information as control information to the frame processing unit 220. The frame processing unit 220 then generates a trigger frame including the TXS information from the TXS management unit 211 as a control frame (MAC frame) and outputs the trigger frame including the TXS information to the wireless communication unit 240. As a result, the wireless communication unit 240 transmits a wireless signal including the TXS information to terminals 30 wirelessly connected to the wireless station, including the terminal 30 to which part of the TXOP is allocated. Note that a trigger frame including TXS information is also referred to as a "MU-RTS TXS trigger frame" and a "TXS trigger frame."

Figure 8 is a schematic diagram showing an example of the format of a TXS trigger frame generated by a shared AP in an embodiment. As shown in Figure 8, the TXS trigger frame includes a Common Info field and a User Info field. The Common Info field stores information indicating that the trigger frame is a TXS trigger frame. The Common Info field includes a Triggered TXOP Sharing Mode subfield and a TXOP Return subfield in Triggered TXOP Sharing Mode 2.

The Triggered TXOP Sharing Mode subfield stores information regarding whether or not to apply the TXS function, and if the TXS function is applied, stores information regarding whether or not to apply P2P communication. In one example, if the TXS function is not applied, the field value of the Triggered TXOP Sharing Mode subfield is set to 0. In this case, the shared AP 20 does not allocate the acquired TXOP to the wirelessly connected terminal 30. Furthermore, if the TXS function is applied and P2P communication is not applied, the field value of the Triggered TXOP Sharing Mode subfield is set to 1. In this case, the shared AP 20 allocates a portion of the acquired TXOP to the wirelessly connected terminal 30 as a communication enabled period. However, a terminal 30 that has been allocated a portion of the TXOP can transmit data with the wirelessly connected shared AP 20 during the allocated communication period, but will not perform P2P communication with other terminals 30 other than its own station.

Furthermore, when the TXS function and P2P communication are applied, the field value of the Triggered TXOP Sharing Mode subfield is set to 2. In this case, the shared AP 20 allocates a portion of the acquired TXOP to the wirelessly connected terminal 30 as a communication period. Then, the terminal 30 to which a portion of the TXOP has been allocated can transmit data with the wirelessly connected shared AP 20 during the allocated communication period, and can also perform P2P communication with other terminals 30 other than the terminal itself, provided that the field value of the TXOP Return subfield in Triggered TXOP Sharing Mode 2 is 1. However, even if the field value of the Triggered TXOP Sharing Mode subfield is 2, if the field value of the TXOP Return subfield in Triggered TXOP Sharing Mode 2 is other than 1, P2P communication will not take place between multiple terminals 30.

Furthermore, in the TXS trigger frame, at least a portion of the TXS information is stored in the User Info field. The User Info field includes an Allocation Duration subfield and a Reserved subfield. In one example, when P2P communication is applied, information regarding the time range during which P2P communication can be performed is stored in the Allocation Duration subfield or the Reserved subfield.

In one example, information regarding the time range during which P2P communication is possible may be stored in a management frame or control frame separate from the TXS trigger frame. In this case, information regarding the time range during which P2P communication is possible is stored, for example, in a reserved bit in the Information field format (not shown) of the management frame or control frame, or in the User Info field of the trigger frame used by the PSR (parameterized spatial reuse) function. In this case too, information regarding the time range during which P2P communication is possible is transmitted to the terminal 30 wirelessly connected to the shared AP 20 by a wireless signal converted from the management frame or control frame.

In a communication system 1 in which a shared AP 20 and terminals 30, etc., perform communication operations based on the TXS function as in the embodiment, P2P communication may occur between multiple terminals 30α wirelessly connected to AP 20α, one of the shared APs 20, and a situation may arise in which AP (first AP) 20β, a shared AP 20 other than AP 20α, transmits data between terminal 30β to which it is wirelessly connected. Furthermore, a situation may arise in which data transmission occurs between AP 20β and terminal 30β in the vicinity of terminal 30α performing P2P communication, and data transmission occurs between AP 20β and terminal 30β using the same frequency band or the same channel as the P2P communication between terminals 30α. In such a situation, particularly when low-latency traffic is transmitted between AP 20β and terminal 30β, it is necessary to suppress interference of data transmission via P2P communication between terminals 30α with the transmission of low-latency traffic between AP 20β and terminal 30β, from the perspective of ensuring the low latency of the low-latency traffic.

Furthermore, in communication system 1, in addition to P2P communication between terminals 30α and transmission of low-latency traffic between AP 20β and terminal 30β, a situation may arise in which P2P communication is performed between multiple terminals 30γ that are wirelessly connected to AP (second AP) 20γ, which is one of the shared APs 20 other than APs 20α and 20β. In such a situation, it is necessary to suppress interference in data transmission by P2P communication between terminals 30α with respect to transmission of low-latency traffic between AP 20β and terminal 30β, and it is also necessary to suppress interference in data transmission by P2P communication between terminals 30γ. It is also necessary to suppress interference in data transmission by P2P communication between terminals 30γ with respect to data transmission by P2P communication between terminals 30α.

In this embodiment, when P2P communication between terminals 30α, transmission of low-latency traffic between AP 20β and terminal 30β, and P2P communication between terminals 30γ occur, sharing AP 10 cooperates with shared APs 20α, 20β, and 20γ, and terminals 30α, 30β, and 30γ to perform the processing (communication processing) described below. In the following description, AP 20α is also referred to as the "first associated AP," AP 20β is also referred to as the "first AP" and the "second associated AP," and AP 20γ is also referred to as the "second AP" and the "third associated AP." In the following description, it is assumed that P2P communication between terminals 30α and P2P communication between terminals 30γ occur using the same frequency band or the same channel as the transmission of low-latency traffic between AP 20β and terminal 30β. Unless otherwise specified, it is assumed that, in the vicinity of terminal 30α performing P2P communication, low-latency traffic is transmitted between AP 20β and terminal 30β, and P2P communication is also performed between terminals 30γ.

The transmission period management unit 121 of sharing AP 10 cooperates with the transmission period management unit 212 of each of APs 20α and 20β and the transmission period adjustment unit 321 of each of terminals 30α and 30β to adjust the periods during which P2P communication between terminals 30α and low-latency traffic is transmitted between AP 20β and terminal 30β. The transmission period management unit 121 of sharing AP 10 also cooperates with the transmission period management unit 212 of each of APs 20α, 20β, and 20γ and the transmission period adjustment unit 321 of each of terminals 30α, 30β, and 30γ to adjust the periods during which P2P communication between terminals 30α and 30γ is transmitted, and the periods during which low-latency traffic is transmitted between AP 20β and terminal 30β.

FIG. 9 is a flowchart showing an example of processing performed by an AP to which multiple terminals performing P2P communication are wirelessly connected when P2P communication is performed between multiple terminals and when low-latency traffic is transmitted between the AP and the terminals in an embodiment. In the following explanation, the example of processing shown in FIG. 9 is described as processing performed by the transmission period management unit 212 of the AP (first home AP) 20α to which terminal 30α is wirelessly connected, in cooperation with the transmission period management unit 121 of the sharing AP 10 and the transmission period adjustment unit 321 of each terminal 30α, when P2P communication is performed between multiple terminals 30α and low-latency traffic is transmitted between the AP (first AP and second home AP) 20β and terminal 30β. The example of processing shown in FIG. 9 is also described assuming that in addition to P2P communication between terminals 30α, P2P communication may also be performed between multiple terminals 30γ wirelessly connected to the AP (second AP and third home AP) 20γ.

When the processing of the example in Figure 9 begins, the transmission period management unit 212 of AP 20α acquires information related to the transmission of low-latency traffic between AP 20β and terminal 30β (S401). The information related to the transmission of low-latency traffic includes information related to the period for transmitting low-latency traffic. The information related to the transmission of low-latency traffic is notified as management information from AP 20β to AP 20α via sharing AP 10, for example. In one example, the information related to the transmission of low-latency traffic is notified directly from AP 20β to AP 20α without going through sharing AP 10. Furthermore, if terminal 30β is wirelessly connected to AP 20α in addition to AP 20β, the information related to the transmission of low-latency traffic may be notified directly from terminal 30β to AP 20α.

Then, the transmission period management unit 212 of AP 20α determines whether P2P communication is taking place between multiple terminals 30γ (S402). This determines whether P2P communication is taking place between multiple terminals 30γ that are wirelessly connected to AP 20γ, which is a shared AP 20 other than AP 20α. If P2P communication is taking place between terminals 30γ, information regarding the P2P communication between terminals 30γ is notified to AP 20α as management information from AP 20γ via sharing AP 10 or directly from AP 20γ. This causes the transmission period management unit 212 of AP 20α to determine that P2P communication is also taking place between multiple terminals 30γ that are wirelessly connected to APs 20γ other than its own station, apart from P2P communication between terminals 30α. In addition, if one of the terminals 30γ is wirelessly connected to AP 20α in addition to AP 20γ, information regarding P2P communication between the terminals 30γ may be notified directly to AP 20α from one of the terminals 30γ.

If P2P communication is not taking place between terminals 30γ (S402-No), the transmission period management unit 212 of AP 20α cooperates with the transmission period management unit 121 of sharing AP 10 and the transmission period adjustment unit 321 of each terminal 30α to adjust the period for P2P communication between terminals 30α to a time range excluding the period for transmitting low-latency traffic between AP 20β and terminal 30β (S403). This avoids the period for transmitting low-latency traffic between AP 20β and terminal 30β, allowing data to be transmitted between multiple terminals 30α via P2P communication.

Furthermore, in the processing of S403, the transmission period management unit 212 of AP 20α etc. adjusts the order of P2P communication between terminals 30α and the transmission of low-latency traffic between AP 20β and terminal 30β so that the transmission of low-latency traffic between AP 20β and terminal 30β is given priority over P2P communication (data transmission) between terminals 30α. In this case, the order is adjusted so that, for example, data transmission via P2P communication between terminals 30α is carried out after the transmission of low-latency traffic between AP 20β and terminal 30β has finished.

When P2P communication is performed between terminals 30γ (S402-Yes), the transmission period management unit 212 of AP 20α cooperates with the transmission period management unit 121 of sharing AP 10, the transmission period management unit 212 of AP 20γ, and the transmission period adjustment units 321 of terminals 30α and 30γ to adjust the period for P2P communication between terminals 30α and between terminals 30γ to a time range excluding the period for transmitting low-latency traffic between AP 20β and terminal 30β (S404). This allows data to be transmitted via P2P communication between multiple terminals 30α, and data to be transmitted via P2P communication between multiple terminals 30γ other than terminal 30α, avoiding the period for transmitting low-latency traffic between AP 20β and terminal 30β.

Furthermore, in the processing of S404, the transmission period management units 212 of APs 20α and 20γ adjust the order of P2P communication between terminals 30α, P2P communication between terminals 30γ, and transmission of low-latency traffic between AP 20β and terminal 30β so that the transmission of low-latency traffic between AP 20β and terminal 30β is given priority over P2P communication (data transmission) between terminals 30α, and P2P communication (data transmission) between terminals 30γ. In this case, the order is adjusted so that, for example, after the transmission of low-latency traffic between AP 20β and terminal 30β is completed, data transmission via P2P communication between terminals 30α and P2P communication between terminals 30γ takes place.

Furthermore, when P2P communication is performed between terminals 30γ (S402-Yes), the transmission period management unit 212 of AP 20α adjusts the order of P2P communication (data transmission) between terminals 30α and P2P communication (data transmission) between terminals 30γ within a time range excluding the period during which low-latency traffic is transmitted between AP 20β and terminal 30β (S405). In this case, the period during which P2P communication is performed between terminals 30α is adjusted to a time range different from both the period during which low-latency traffic is transmitted between AP 20β and terminal 30β and the period during which P2P communication is performed between terminals 30γ. As a result, data is transmitted via P2P communication between multiple terminals 30α, avoiding the period during which low-latency traffic is transmitted between AP 20β and terminal 30β as well as the period during which terminals 30γ are performing P2P communication (data transmission).

In one example, the order of P2P communication between terminals 30α and between terminals 30γ is set in advance. Then, P2P communication between terminals 30α and between terminals 30γ is performed in the predetermined order. Furthermore, if there are three or more pairs of terminals 30 performing P2P communication with each other, the order of the pairs performing P2P communication may be updated periodically.

In another example, the order of pairs performing P2P communication is set by the transmission period management unit 121 of the sharing AP 10. In this case, the transmission period management unit 121 of the sharing AP 10 acquires, for example, for each of the shared APs 20 to which it belongs, the number of terminals 30 that need to transmit high-priority data (traffic) among the terminals 30 wirelessly connected to that shared AP 20. The transmission period management unit 121 then assigns a higher priority to P2P communication to terminals 30 in a pair that are wirelessly connected to a shared AP 20 that has a greater number of terminals 30 that need to transmit high-priority data. In this case, data transmission via P2P communication is performed in order from the terminal 30 in the pair with the highest priority. The priority of the data to be transmitted is determined, for example, based on the TID (traffic identifier).

In another example, when there are two or more sets of terminals 30 performing P2P communication, the transmission period management unit 121 of the sharing AP 10 adjusts the order of the sets performing P2P communication, as well as the length of time for each of the two or more sets to perform P2P communication. In this case, the earlier a set of terminals 30 performs P2P communication, the longer the length of time for P2P communication may be set, and vice versa.

When the data transmission order is adjusted by the process of the example shown in FIG. 9 , each shared AP 20 notifies the terminals 30 wirelessly connected to it, i.e., the terminals 30 subordinate to it, of the adjusted data transmission order as management information or control information. Each terminal 30 then performs communication operations in accordance with the notified data transmission order. Therefore, data transmission between terminals 30α and low-latency traffic transmission between AP 20β and terminal 30β is performed in accordance with the adjusted data transmission order. Furthermore, when data transmission is performed between terminals 30γ, data transmission between terminals 30α, data transmission between terminals 30γ, and low-latency traffic transmission between AP 20β and terminal 30β is performed in accordance with the adjusted data transmission order.

In one example, the period during which low-latency traffic is transmitted between AP 20β and terminal 30β is notified in advance to each of terminals 30α and 30γ. Then, the transmission period adjustment unit 321 of each terminal 30α avoids the notified period to allow P2P communication between terminals 30α, and the transmission period adjustment unit 321 of each terminal 30γ avoids the notified period to allow P2P communication between terminals 30γ. The period during which low-latency traffic is transmitted between AP 20β and terminal 30β may be notified to each of terminals 30α and 30γ as an R-TWT SP (service period), which is a service period set using the R-TWT function. The period during which low-latency traffic is transmitted between AP 20β and terminal 30β is notified, for example, by transmitting a radio signal converted from either a management frame or a control frame to each of terminals 30α and 30γ.

In another example, low-latency traffic is transmitted periodically between AP 20β and terminal 30β. APs 20α, 20γ and terminals 30α, 30γ, etc. acquire information regarding the period of low-latency traffic transmission between AP 20β and terminal 30β in advance. Based on the information regarding the period of low-latency traffic transmission between AP 20β and terminal 30β, P2P communication is performed between terminals 30α and between terminals 30γ, avoiding the period when low-latency traffic is transmitted between AP 20β and terminal 30β.

In one example, each shared AP 20 notifies the terminals 30 wirelessly connected to it, i.e., the terminals 30 subordinate to it, of the time range (period) during which P2P communication is possible, based on the data transmission order adjusted as described above. As a result, the time range during which P2P communication is possible between terminals 30α is notified by AP 20α, and the time range during which P2P communication is possible between terminals 30γ is notified by AP 20γ. Information regarding the time range during which P2P communication is possible is notified to the subordinate terminals 30 by transmitting a wireless signal converted from either a management frame (e.g., an action frame) or a control frame. When notifying information regarding the time range during which P2P communication is possible using a wireless signal converted from a TXS trigger frame, information regarding the time range during which P2P communication is possible is stored, for example, in the Allocation Duration subfield or the Reserved subfield of the User Info field of the TXS trigger frame.

In another example, until transmission of low-latency traffic between AP 20β and terminal 30β is completed, each of APs 20α and 20γ sets the field value of the TXOP Return subfield in Triggered TXOP Sharing Mode 2 in the Common Info field of the TXS trigger frame to a value other than 1. Then, wireless signals converted from the TXS trigger frame are transmitted from each of APs 20α and 20γ to their subordinate terminals 30, thereby controlling the communication operations of terminals 30α and 30γ so that P2P communication between terminals 30α and 30γ is not performed until transmission of low-latency traffic between AP 20β and terminal 30β is completed.

In another example, one of the terminals 30α can detect the communication status of either AP 20β or terminal 30β. Then, in response to detecting that low-latency traffic is being transmitted between AP 20β and terminal 30β, the transmission period adjustment unit 321 of one of the terminals 30α controls the communication operation of terminal 30α to a state where P2P communication is not performed between terminals 30α. Furthermore, in response to detecting that low-latency traffic is being transmitted between AP 20β and terminal 30β, the transmission period adjustment unit 321 of one of the terminals 30γ may control the communication operation of terminal 30γ to a state where P2P communication is not performed between terminals 30γ.

In one example, provided that AP 20α is located at a specified distance or more from AP 20β, which transmits low-latency traffic between AP 20β and terminal 30β, the transmission period management unit 212 of AP 20α will initiate P2P communication between terminals 30α wirelessly connected to the AP itself, even while low-latency traffic is being transmitted between AP 20β and terminal 30β. In this case, the sharing AP 10 stores information such as the location coordinates of APs 20α and 20β, and the management unit 120 calculates the distance between APs 20α and 20β based on the information on the location coordinates. The management unit 120 of the sharing AP 10 may also obtain information on the received power detected by each of APs 20α and 20β, and calculate the distance between APs 20α and 20β based on the information on the received power.

Figure 10 is a sequence diagram showing an example of the order of data transmission when P2P communication is performed between multiple terminals and low-latency traffic is transmitted between a terminal and a shared AP in a communication system according to an embodiment. In the example of Figure 10, shared AP 20-1 (AP1) corresponds to AP (first associated AP) 20α, and terminals 30-1A (STA1A) and 30-1B (STA1B) wirelessly connected to AP1 correspond to terminal 30α. Shared AP 20-2 (AP2) corresponds to AP (first associated AP and second associated AP) 20β, and terminal 30-2 (STA2) wirelessly connected to AP2 corresponds to terminal 30β. The shared AP 20-3 (AP3) corresponds to the AP (second AP and third home AP) 20γ, and the terminals 30-3A (STA3A) and 30-3B (STA3B) wirelessly connected to AP3 correspond to the terminal 30γ.

In the example shown in Figure 10, P2P communication between STA1A and STA1B, which are wirelessly connected to AP1, and P2P communication between STA3A and STA3B, which are wirelessly connected to AP3, are each carried out while avoiding the period during which low-latency traffic is transmitted between AP2 and STA2. The transmission of low-latency traffic between AP2 and STA2 is given priority over P2P communication between STA1A and STA1B and P2P communication between STA3A and STA3B. Therefore, P2P communication between STA1A and STA1B and P2P communication between STA3A and STA3B are carried out after the transmission of low-latency traffic between AP2 and STA2 has finished.

Furthermore, in the example of Figure 10, the order of P2P communication between STA1A and STA1B and P2P communication between STA3A and STA3B is adjusted within a time range excluding the period during which low-latency traffic is transmitted between AP2 and STA2. P2P communication between STA3A and STA3B is then carried out, avoiding the period during which P2P communication is carried out between STA1A and STA1B, and P2P communication between STA3A and STA3B is carried out after P2P communication between STA1A and STA1B has ended.

FIG. 11 is a sequence diagram showing another example, different from FIG. 10, of the order of data transmission when P2P communication is performed between multiple terminals and when low-latency traffic is transmitted between a terminal and a shared AP in a communication system according to an embodiment. In the example of FIG. 11, as in the example of FIG. 10, AP1 corresponds to AP (first associated AP) 20α, STA1A and STA1B correspond to terminal 30α, AP2 corresponds to AP (first associated AP and second associated AP) 20β, STA2 corresponds to terminal 30β, AP3 corresponds to AP (second associated AP and third associated AP) 20γ, and STA3A and STA3B correspond to terminal 30γ.

In the example of FIG. 11, before information regarding the transmission of low-latency traffic between AP2 and STA2 is notified, the order of data transmission is adjusted so that P2P communication between STA3A and STA3B begins after P2P communication between STA1A and STA1B has ended. In the example of FIG. 11, while data transmission via P2P communication is taking place between STA1A and STA1B, AP2 notifies AP0, the sharing AP10, of information regarding the transmission of low-latency traffic between AP2 and STA2 (S411). AP0 then notifies AP1 and AP3, respectively, of information regarding the transmission of low-latency traffic between AP2 and STA2 (S412, S413).

In the example of Figure 11, low-latency traffic transmission between AP2 and STA2 is given priority over P2P communication between STA3A and STA3B. Therefore, when P2P communication between STA1A and STA1B ends, low-latency traffic transmission between AP2 and STA2 occurs before P2P communication between STA3A and STA3B. In other words, the data transmission order is updated so that P2P communication between STA3A and STA3B occurs after low-latency traffic transmission between AP2 and STA2 ends (S414).

As described above, in the embodiments, when AP 20α, one of the shared APs 20, transmits low-latency traffic between terminal 30β, which is wirelessly connected to AP (first AP) 20β, which is one of the APs other than its own station, the management unit 210, etc. of AP 20α avoids the period during which low-latency traffic is transmitted between AP 20β and terminal 30β, and transmits data between multiple terminals 30α wirelessly connected to its own station. This processing effectively suppresses interference of data transmission by P2P communication between terminals 30α with the transmission of low-latency traffic. This appropriately ensures low latency for the low-latency traffic transmitted between AP 20β and terminal 30β.

Furthermore, in embodiments, the management unit 210 of AP 20α adjusts the order of data transmission between terminals 30α and the order of low-latency traffic transmission between AP 20β and terminal 30β so that low-latency traffic transmission between AP 20β and terminal 30β is prioritized over data transmission between terminals 30α. By prioritizing low-latency traffic transmission over P2P communication between terminals 30α, the low latency of the low-latency traffic transmitted between AP 20β and terminal 30β is further ensured.

Furthermore, in the embodiments, in addition to transmitting low-latency traffic between AP 20β and terminal 30β, when data is transmitted between multiple terminals 30γ wirelessly connected to AP (second AP) 20γ, which is one of the APs other than AP 20β, the management unit 210 of AP 20α adjusts the order of data transmission between terminals 30α and between terminals 30γ within a time range excluding the period during which low-latency traffic is transmitted between AP 20β and terminal 30β. This effectively suppresses interference of P2P communication between terminals 30α with low-latency traffic transmission, as well as interference of P2P communication between terminals 30γ with low-latency traffic transmission. Furthermore, interference of data transmission between terminals 30γ with data transmission between terminals 30α is also effectively suppressed.

The number of shared APs 20 belonging to a sharing AP 10 is not particularly limited, as long as it is plural. In other words, in a multi-AP connection method in which multiple shared APs 20 belong to a sharing AP 10, AP (first belonging AP) 20α, which is one of the shared APs 20, can transmit data between multiple terminals 30α wirelessly connected to its own station, avoiding the period in which low-latency traffic is transmitted between AP (first AP and second belonging AP) 20β, which is one of the APs other than its own station, and terminal 30β.

Furthermore, in the above-described embodiment, the functions of the sharing AP and the shared AP are completely separate, but in some variations, the sharing AP may also have the functions of a shared AP. For example, in a communication system 1 similar to that shown in FIG. 1, the sharing AP 10 may perform the processing of the shared AP 20-1 in addition to the processing described above. In this case, the sharing AP 10 has, as its functional configuration, an upper layer processing unit 110, a management unit 120, a frame processing unit 130, and a transmission/reception unit 140, as well as a management unit 210, a frame processing unit 220, and a wireless communication unit 240.

In a sharing AP 10 with shared AP functionality, the transmitter/receiver 140 transmits and receives data, management information, control information, etc., via wireless or wired communication with each of the shared APs 20 to which it belongs, such as shared AP 20-2. In addition, in the sharing AP 10, the wireless communication unit 240 can transmit and receive data, management information, control information, etc., via wireless communication with each of the terminals 30 located (wirelessly connected) within the communication area. Furthermore, data, management information, control information, etc. are exchanged between the frame processing unit 130 included in the functionality of the sharing AP 10 and the frame processing unit 220 included in the functionality of the shared AP.

In a communication system 1 provided with a sharing AP 10 having the functionality of a shared AP, the sharing AP 10 is capable of performing the same processing as the aforementioned AP 20α. For example, the management unit 210 of the sharing AP 10, as in the above-mentioned embodiment, avoids the period during which low-latency traffic is transmitted between the AP (first AP) 20β, which is one of the APs other than the own station, and the terminal 30β, and transmits data via P2P communication between the multiple terminals 30α wirelessly connected to the own station.

Furthermore, in the above-described embodiments, the connection between the sharing AP 10 and the terminal 30 passes through one shared AP 20, but in one variation, the connection between the sharing AP 10 and the terminal 30 may pass through two or more shared APs. In other words, the processing of the above-described embodiments can also be applied to a multi-AP connection method with a multi-stage configuration in which two or more shared APs 20 are interposed between the sharing AP 10 and the terminal 30. Therefore, even in a multi-AP connection method with a multi-stage configuration, AP 20α, which is one of the APs, transmits data between multiple terminals 30α wirelessly connected to its own station, avoiding the period during which low-latency traffic is transmitted between AP 20β (first AP), which is one of the APs other than its own station, and terminal 30β.

Furthermore, in one variant, multiple sharing APs 10 may be provided in the communication system 1, and the multiple sharing APs 10 may be able to communicate with each other via the network 40. In other words, even if AP 20β belongs to a sharing AP other than the sharing AP 10 to which AP 20α belongs, the processing of the above-mentioned embodiment and the like may be applied. In other words, even if AP 20β belongs to a sharing AP other than the sharing AP 10 to which AP 20α belongs, AP 20α avoids the period during which low-latency traffic is transmitted between AP 20β (first AP) 20β, which is one of the APs other than its own station, and terminal 30β, and transmits data between the multiple terminals 30α wirelessly connected to its own station.

Furthermore, the processes of the above-mentioned embodiments can be stored as a program that can be executed by a processor, which is a computer. Furthermore, a program that executes the above-mentioned processes can be stored and distributed in a storage medium of an external storage device, such as a magnetic disk, optical disk, or semiconductor memory. The processor can then read the program stored in the storage medium of this external storage device, and its operation can be controlled by the read program, thereby executing the processes of the embodiments.

The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the various embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the multiple elements disclosed. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

1...Communication system 10...Sharing AP
11, 21, 31...CPU
12, 22, 32...ROM
13, 23, 33...RAM
14, 24, 34...wireless communication modules 15...wired communication module 20 (20-1, 20-2, 20-3)...shared AP
30 (30-1A, 30-1B, 30-2, 30-3A, 30-3B)...Terminal 35...Display 36...Storage 40...Network 110, 310...Upper layer processing unit 120, 210, 320...Management unit 121, 212...Transmission period management unit 130, 220, 330...Frame processing unit 140, 230...Transmission/reception unit 211...TXS management unit 240, 340...Wireless communication unit 321...Transmission period adjustment unit

Claims (7)

a wireless communication unit;
a management unit that enables data transmission between a plurality of terminals wirelessly connected to the wireless communication unit, and when a first access point, which is one of access points other than the own station, transmits low-latency traffic between the first access point and a terminal wirelessly connected thereto, causes data transmission between the plurality of terminals while avoiding a period during which the low-latency traffic is transmitted between the first access point and the terminal;
An access point comprising: The access point of claim 1, wherein the management unit adjusts the order of the data transmission between the plurality of terminals and the transmission of the low-latency traffic between the first access point and the terminal so that the transmission of the low-latency traffic between the first access point and the terminal is given priority over the data transmission between the plurality of terminals. The access point of claim 1, wherein, in addition to the transmission of the low-latency traffic between the first access point and the terminal, when data transmission is performed between multiple terminals wirelessly connected to a second access point other than the first access point, the management unit adjusts the order of data transmission between the multiple terminals wirelessly connected to the wireless communication unit and the multiple terminals wirelessly connected to the second access point, within a time range excluding the period during which the low-latency traffic is transmitted between the first access point and the terminal. A terminal for use with the access point of any one of claims 1 to 3, comprising:
a wireless communication unit that establishes a wireless connection with the access point and is capable of transmitting data to a terminal other than the own station that is wirelessly connected to the access point;
a management unit that, when transmitting the low-latency traffic between the first access point and the terminal wirelessly connected thereto, causes data transmission between the wireless communication unit and the other terminal, avoiding the period during which the low-latency traffic is transmitted between the first access point and the terminal;
A terminal comprising: An access point to which a plurality of associated access points belong,
an access point comprising: a management unit that, when data transmission is performed between a plurality of terminals wirelessly connected to a first home access point, which is one of the plurality of home access points, and a second home access point, which is another one of the plurality of home access points other than the first home access point, transmits low-latency traffic between the terminals wirelessly connected to the first home access point, avoiding a period during which the low-latency traffic is transmitted between the second home access point and the terminals; The access point of claim 5, wherein the management unit adjusts the order of the data transmission between the plurality of terminals and the transmission of the low-latency traffic between the second access point and the terminal so that the transmission of the low-latency traffic between the second access point and the terminal is given priority over the data transmission between the plurality of terminals wirelessly connected to the first access point. 7. The access point of claim 5 or 6, wherein, in addition to data transmission between the plurality of terminals wirelessly connected to the first access point and the transmission of the low-latency traffic between the second access point and the terminal, when data transmission is performed between a plurality of terminals wirelessly connected to a third access point that is one of the plurality of access points other than the first and second access points, the management unit adjusts an order of data transmission between the plurality of terminals wirelessly connected to the first access point and the plurality of terminals wirelessly connected to the third access point, within a time range excluding the period during which the low-latency traffic is transmitted between the second access point and the terminal.