Communication device, communication method, and program

Abstract

To allow communication devices to efficiently share information on whether a channel pair during multi-link communication can be simultaneously transmitted and received, and allow the devices to execute efficient multi-link communication.SOLUTION: A communication device has: communication means that can execute in parallel wireless frame communication using a first frequency channel and wireless frame communication using a second frequency channel; and transmission means that transmits, to the other communication device, information that indicates the distance on a frequency axis between the first frequency channel and the second frequency channel, the information indicating a channel distance required for executing in parallel wireless frame transmission using the first frequency channel and wireless frame reception using the second frequency channel in the communication performed by the communication means.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to wireless communication technology. [Background technology]

[0002] With the recent increase in the amount of data being communicated, development of communication technologies such as wireless local area networks (LANs) is progressing. The IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard series is known as a major communication standard for wireless LANs. The IEEE 802.11 standard series includes standards such as IEEE 802.11a / b / g / n / ac / ax. For example, the latest standard, IEEE 802.11ax, uses orthogonal frequency division multiple access (OFDMA) to standardize technology that not only achieves a high peak throughput of up to 9.6 gigabits per second (Gbps) but also improves communication speeds under congested conditions (see Patent Document 1). OFDMA stands for Orthogonal Frequency Division Multiple Access.

[0003] The IEEE802.11be standard is currently being developed as a successor standard that aims to further improve throughput, frequency utilization efficiency, and communication latency.

[0004] IEEE802.11be is considering multi-link communication, in which one access point (AP) establishes multiple links with one station (STA) using frequency bands such as 2.4GHz, 5GHz, and 6GHz, and communicates simultaneously.In addition, due to hardware restrictions on wireless communication devices, consideration is being given to how to handle APs and STAs in multi-link communication when they are unable to receive on one link while transmitting on another link. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-50133 Summary of the Invention [Problem to be solved by the invention]

[0006] To implement efficient multi-link communication, it is necessary for devices performing communication to share information indicating which links can simultaneously transmit and receive data with other links. This is because if a pair of links that cannot send and receive simultaneously are used, the sending and receiving processes must be executed exclusively, which reduces communication efficiency.However, in the past, it had not been decided what information should be shared between devices, or how it should be shared, in order to share information indicating which links can send and receive simultaneously with other links.

[0007] Therefore, the present invention aims to enable communication devices to efficiently share information regarding whether simultaneous transmission and reception of channel pairs during Multi-Link communication is possible, thereby enabling efficient Multi-Link communication to be carried out between devices. [Means for solving the problem]

[0008] In order to achieve the above object, a communication device of the present invention is characterized by having a communication means capable of communicating radio frames using a first frequency channel and communicating radio frames using a second frequency channel in parallel, and a transmission means for transmitting to another communication device information indicating the distance on the frequency axis between the first frequency channel and the second frequency channel, the information indicating the channel distance required to transmit radio frames using the first frequency channel and receive radio frames using the second frequency channel in parallel in communication by the communication means. [Effects of the Invention]

[0009] According to the present invention, it is possible for communication devices to efficiently share information regarding whether simultaneous transmission and reception of channel pairs during Multi-Link communication is possible, thereby enabling efficient Multi-Link communication to be carried out between devices. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a network configuration according to the present invention. [Figure 2] FIG. 2 is a diagram illustrating a hardware configuration of a communication device according to the present invention. [Figure 3] 1 is a block diagram showing a functional configuration of a communication device according to the present invention; [Figure 4] FIG. 10 is a sequence diagram for notifying the channel distance of an STR-enabled link for an association candidate channel in an association response in the first embodiment. [Figure 5] 10 is a diagram illustrating an example of the configuration of an Association Response frame transmitted from an AP 101 to a STA 102 in the first embodiment. [Figure 6] 10 is a flowchart of AP 101 determining the STR possible channel distance in 20 MHz transmission. [Figure 7] 10 is a flowchart for determining whether STR is possible for the pair of channel A and channel B when transmitting at 20 MHz in the AP 101 in the first embodiment. [Figure 8] 10 is a flowchart showing how the AP 101 detects transmission noise during 20 MHz transmission for a pair of channels A and B before communicating with the STA 102 in the second embodiment. [Figure 9] 10 is a flowchart for determining whether STR is possible for the pair of channel A and channel B when transmitting at 20 MHz in the AP 101 in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the configurations shown in the following embodiments are merely examples, and the present invention is not limited to the illustrated configurations.

[0012] (Wireless communication system configuration) 1 shows the configuration of a network in which a communication device 102 (hereinafter, STA102) according to this embodiment participates. The STA102 is a station (STA) that plays a role in participating in the network 100. The communication device 101 (hereinafter, AP101) is an access point (AP) that plays a role in constructing the wireless network 100. The AP101 is capable of communicating with the STA102.

[0013] Each of the AP 101 and the STA 102 can perform wireless communication in accordance with the IEEE 802.11be (EHT) standard. IEEE stands for Institute of Electrical and Electronics Engineers. The AP 101 and the STA 102 can communicate in the 2.4 Hz, 5 GHz, and / or 6 GHz frequency bands. The frequency bands used by each communication device are not limited to these, and different frequency bands, such as the 60 GHz band, may be used. The AP 101 and the STA 102 can also communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz. The bandwidths used by each communication device are not limited to these, and different bandwidths, such as 240 MHz and 4 MHz, may be used.

[0014] The AP 101 and STA 102 perform OFDMA communication compliant with the IEEE802.11be standard, enabling multi-user (MU) communication by multiplexing signals from multiple users. OFDMA stands for Orthogonal Frequency Division Multiple Access. In OFDMA communication, portions of the divided frequency band (RU, Resource Unit) are assigned to each STA without overlapping, and the carrier waves of each STA are orthogonal. This allows the AP to communicate with multiple STAs in parallel within a specified bandwidth.

[0015] Although the AP 101 and the STA 102 are described as being compatible with the IEEE 802.11be standard, they may also be compatible with legacy standards that predate the IEEE 802.11be standard. Specifically, the AP 101 and the STA 102 may be compatible with at least one of the IEEE 802.11a / b / g / n / ac / ax standards. In addition to the IEEE 802.11 series standards, they may also be compatible with other communication standards such as Bluetooth (registered trademark), NFC, UWB, ZigBee, and MBOA. UWB stands for Ultra Wide Band, and MBOA stands for Multi-Band OFDM Alliance. NFC stands for Near Field Communication. UWB includes wireless USB, wireless 1394, WiNET, and the like. They may also be compatible with wired communication standards such as wired LAN. Specific examples of the AP 101 include, but are not limited to, a wireless LAN router, a personal computer (PC), and a smartphone. The AP 101 may also be an information processing device such as a wireless chip capable of performing wireless communication in accordance with the IEEE 802.11be standard. Specific examples of the STAs 102 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, video cameras, and headsets. The STAs 102 may also be information processing devices such as wireless chips capable of performing wireless communication in accordance with the IEEE 802.11be standard. Each communication device can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz.

[0016] In this embodiment, the AP 101 and the STA 102 establish links via multiple frequency channels and perform multi-link communication. In the IEEE 802.11 series of standards, the bandwidth of each channel is defined as 20 MHz. Here, a channel refers to a frequency channel defined in the IEEE 802.11 series of standards, which define multiple channels for each of the 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz frequency bands. By combining or bonding adjacent channels, a single channel may utilize a bandwidth of 40 MHz or more. For example, the AP 101 can establish a link with the STA 102 via a first channel in the 2.4 GHz band and communicate with it. In parallel with this, the STA 102 can establish a link with the AP 101 via a second channel in the 5 GHz band and communicate with it. In this case, the STA 102 maintains a second link via the second channel in parallel with the link via the first channel, thereby performing multi-link communication using Link 103 and Link 104. In this way, the AP 101 can improve the throughput of communication with the STA 102 by establishing links with the STA 102 via multiple channels.

[0017] In multi-link communication, multiple links in different frequency bands may be established between communication devices. For example, the AP 101 and the STA 102 may establish a first link in the 2.4 GHz band, a second link in the 6 GHz band, and a third link in the 5 GHz band. Alternatively, links may be established via multiple different channels within the same frequency band. For example, a link on channel 6 in the 2.4 GHz band may be established as the first link, and a link on channel 1 in the 2.4 GHz band may be established as the second link. Note that multiple links in the same frequency band and links in different frequency bands may be mixed. For example, the AP 101 and the STA 102 may establish a link on channel 6 in the 2.4 GHz band, as well as a link on channel 1 in the 2.4 GHz band and a link on channel 149 in the 5 GHz band. By establishing multiple connections with the STA 102 on different frequencies, the AP 101 can establish communication with the STA 102 in another frequency band (e.g., the 5 GHz band) even when one frequency band (e.g., the 2.4 GHz band) is congested. This makes it possible to prevent a decrease in throughput and communication delays in communication with the STA 102.

[0018] Although the wireless network 100 in Fig. 1 is configured with one AP and one STA, the number and arrangement of the APs and STAs are not limited to this. For example, one or more STAs may be added to the wireless network in Fig. 1. In this case, the frequency band, number of links, and bandwidth of each established link may differ for each STA.

[0019] When performing multi-link communication, the AP 101 and the STA 102 divide a single piece of data and transmit it to the other device via multiple links. The AP 101 and the STA 102 may also be capable of MIMO (Multiple-Input and Multiple-Output) communication. In this case, the AP 101 and the STA 102 each have multiple antennas, and one transmits different signals from each antenna using the same channel. The receiving side simultaneously receives all signals arriving from multiple streams using multiple antennas, and separates and decodes the signals of each stream. By performing MIMO communication in this way, the AP 101 and the STA 102 can communicate more data in the same amount of time than if they did not perform MIMO communication. When performing multi-link communication, the AP 101 and the STA 102 may also perform MIMO communication on some or all of the links.

[0020] (AP and STA configuration) 2 shows an example of the hardware configuration of the AP 101 in this embodiment. The AP 101 has a storage unit 201, a control unit 202, a function unit 203, an input unit 204, an output unit 205, a communication unit 206, and an antenna 207. Note that there may be multiple antennas.

[0021] The storage unit 201 is configured with one or more memories such as ROM and RAM, and stores various information such as computer programs for performing various operations described below and communication parameters for wireless communication. ROM stands for Read Only Memory, and RAM stands for Random Access Memory. In addition to memories such as ROM and RAM, the storage unit 201 may also use storage media such as flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, and DVDs. Furthermore, the storage unit 201 may include multiple memories.

[0022] The control unit 202 is configured with one or more processors, such as a CPU or MPU, and controls the entire AP 101 by executing a computer program stored in the storage unit 201. The control unit 202 may control the entire AP 101 in cooperation with the computer program stored in the storage unit 201 and an OS (Operating System). The control unit 202 also generates data and signals (wireless frames) to be transmitted in communication with other communication devices. The CPU stands for Central Processing Unit, and the MPU stands for Micro Processing Unit. The control unit 202 may also be equipped with multiple processors, such as multi-core processors, and the entire AP 101 may be controlled by the multiple processors.

[0023] Furthermore, the control unit 202 controls the function unit 203 to perform predetermined processes such as wireless communication, image capture, printing, projection, etc. The function unit 203 is hardware that enables the AP 101 to perform predetermined processes.

[0024] The input unit 204 receives various operations from the user. The output unit 205 outputs various types of information to the user via a monitor screen or a speaker. Here, the output from the output unit 205 may be a display on a monitor screen, an audio output from a speaker, a vibration output, or the like. Note that both the input unit 204 and the output unit 205 may be implemented by a single module, such as a touch panel. Furthermore, the input unit 204 and the output unit 205 may be integrated with the AP 101 or may be separate units.

[0025] The communication unit 206 controls wireless communication conforming to the IEEE 802.11be standard. The communication unit 206 may also control wireless communication conforming to other IEEE 802.11 series standards in addition to the IEEE 802.11be standard, and may control wired communication such as a wired LAN. The communication unit 206 controls the antenna 207 to transmit and receive signals generated by the control unit 202 for wireless communication.

[0026] If the AP 101 supports the NFC standard, Bluetooth standard, or the like in addition to the IEEE 802.11be standard, it may control wireless communications in accordance with these communication standards. If the AP 101 can perform wireless communications in accordance with multiple communication standards, it may be configured with separate communication units and antennas compatible with each communication standard. The AP 101 communicates data such as image data, document data, and video data with the STA 102 via the communication unit 206. The antenna 207 may be configured separately from the communication unit 206, or may be configured together with the communication unit 206 as a single module.

[0027] The antenna 207 is an antenna capable of communication in the 2.4 GHz band, the 5 GHz band, and the 6 GHz band. In this embodiment, the AP 101 has one antenna, but it may have three antennas. Alternatively, it may have a different antenna for each frequency band. Furthermore, if the AP 101 has multiple antennas, it may have a communication unit 206 corresponding to each antenna. The STA 102 has the same hardware configuration as the AP 101.

[0028] 3 shows a block diagram of the functional configuration of the AP 101 in this embodiment. The STA 102 has a similar configuration. Here, the AP 101 is assumed to include a wireless LAN control unit 301. The number of wireless LAN control units is not limited to one, and may be two, or three or more. The AP 101 further includes a frame generation unit 302, a transmission time control unit 303, a beacon control unit 304, a UI control unit 305, a storage unit 306, and a wireless antenna 307.

[0029] The wireless LAN control unit 301 includes an antenna and circuit for transmitting and receiving wireless signals to and from other wireless LAN devices, and a program for controlling them. The wireless LAN control unit 301 controls wireless LAN communications based on frames generated by the frame generation unit 302 in accordance with the IEEE 802.11 standard series.

[0030] The frame generation unit 302 generates a wireless control frame to be transmitted by the wireless LAN control unit 301. The contents of the wireless control generated by the frame generation unit 302 may be restricted by settings stored in the storage unit 306. They may also be changed by user settings from the UI control unit 305. Information on the generated frame is sent to the wireless LAN control unit 301 and transmitted to the communication partner.

[0031] The transmission time control unit 303 controls the timing at which to issue an instruction to transmit a frame, in accordance with the time interval received from the beacon control unit 304. In accordance with the instruction from the transmission time control unit 303, the wireless LAN control unit 301 transmits the frame generated by the frame generation unit 302.

[0032] The beacon control unit 304 issues instructions to the frame generation unit 302 and the transmission time control unit 303 regarding the timing of transmitting a beacon and the information to be included in the beacon. When the AP 101 starts operating as an AP, the transmission control unit 303 sets the time for periodically transmitting a beacon. In addition, when the transmission time control unit 303 issues an instruction to transmit a beacon, it also instructs the frame generation unit 302 as to the content to be included in the beacon. The frame generation unit 302 obtains information from the storage unit 306 based on the instruction.

[0033] The UI control unit 305 includes hardware related to a user interface, such as a touch panel or buttons for accepting operations on the AP by a user (not shown), and a program for controlling these. The UI control unit 305 also has a function for presenting information to the user, such as displaying images or outputting audio.

[0034] The storage unit 306 is a storage device that can be configured with a ROM, a RAM, etc., that stores programs and data that the AP runs on.

[0035] Example 1 Figure 4 shows a sequence diagram in which AP 101 notifies STA 102 of the channel distance of links for which STR is possible for association candidate channels. This sequence shows an example in which this notification is made using an Association Response. Here, STR stands for simultaneous transmit and receive, and is defined in the IEEE 802.11 standard. STR means that in a pair of links used in multi-link communication, while transmitting on one link, the other link receives (or vice versa).

[0036] AP101 and STA102 each have a wireless LAN control unit 301 corresponding to each of a plurality of links. In FIG. 4, AP411 of AP101 is the wireless LAN control unit 301 for the first link, AP412 is the wireless LAN control unit 301 for the second link, and AP413 is the wireless LAN control unit 301 for the third link. Also, STA421 of STA102 is the wireless LAN control unit 301 for the first link, STA422 is the wireless LAN control unit 301 for the second link, and STA423 is the wireless LAN control unit 301 for the third link. In this embodiment, as an example, STA421 and AP411 are assumed to perform communication processing via channel 1 in the 2.4 GHz band. STA422 and AP412 are assumed to perform communication processing via channel 5 in the 2.4 GHz band. STA423 and AP413 are assumed to perform communication processing via channel 10 in the 2.4 GHz band.

[0037] The processing of this sequence is started in response to the power-on of each of the AP 101 and the STA 102. Alternatively, at least one of the AP 101 and the STA 102 may start the processing in response to an instruction to start Multi-Link communication from a user or an application. Alternatively, at least one of the AP 101 and the STA 102 may start the processing in response to the amount of data to be communicated with the other device reaching or exceeding a predetermined threshold.

[0038] First, the AP 101 transmits a Beacon including its own network information on channel 1, thereby notifying surrounding STAs of its own network information (S401). Specifically, the network information is the transmission interval at which the AP 101 transmits a beacon and the SSID of the AP 101. SSID stands for Service Set Identifier. In addition, the AP 101 may broadcast its Multi-Link communication capability information as network information by including it in the Beacon.

[0039] When the STA 102 receives the Beacon from the AP 101 transmitted on channel 1, it transmits a Probe Request on channel 1 to inquire about the network information of the AP 101 (S402). The Probe Request includes the SSID of the AP 101. In addition, the STA 102 notifies the AP 101 of its capability information related to Multi-Link communication by including it in the Probe Request.

[0040] When the AP 101 receives the Probe Request, it transmits a Probe Response to the STA 102 via 1ch as a response (S403). If the AP 101 did not include capability information related to Multi-Link communication in the Beacon, it transmits the Probe Response with the capability information included in the Beacon. Alternatively, the AP 101 may include only a portion of the capability information related to Multi-Link communication in the Beacon, and include the remaining information or all of the information in the Probe Response.

[0041] By performing the processes of S401 to S403, the AP 101 and the STA 102 can exchange capability information regarding their respective Multi-Link communications.

[0042] Next, the STA 102 transmits an Association Request to the AP 101 on channel 1 as a connection request to the network formed by the AP 101 (S404). Here, the STA 102 may notify the AP 101 by including its capability information regarding multi-link communication in the Association Request. The STA 102 may determine the capability information to transmit in S404 based on the capability information regarding multi-link communication of the AP 101 detected in at least one of S401 and S403. For example, even if the STA 102 can combine links in the 2.4 GHz band and the 5 GHz band, the AP 101 may only support multi-link communication using multiple links in the 2.4 GHz band. In this case, the STA 102 may transmit only capability information regarding the establishment of multiple links in the 2.4 GHz band as the capability information to be transmitted in this step. In addition, in this embodiment, the STA 102 transmits capability information related to its own Multi-Link communication in S402, but this is not limiting and the capability information may not be transmitted in S402 but may be transmitted only in this step. Alternatively, the STA 102 may include request information requested when performing Multi-Link communication in the Association Request. The request information requested by the STA 102 may be indicated by the capability information related to Multi-Link, or may be indicated by another Element.

[0043] When the AP 101 receives the Association Request, it transmits an Association Response to the STA 102 over 1ch as a response (S405). The transmitted Association Response includes the STR-enabled channel distance for each of one or more transmission bandwidths. The STR-enabled channel distance is information indicating how far apart multiple links used in multi-link communication must be on the frequency axis to enable parallel transmission and reception, i.e., whether STR is possible. In other words, the STR-enabled channel distance is the distance on the frequency axis between the frequency channels used by each of the multiple links used in multi-link communication. For example, if STR is possible when the links are separated by 5ch, the STR-enabled channel distance is 5 (or 5ch). This value differs depending on the device. In this embodiment, the STR-enabled channel distance of the AP 101 is set to a distance of 5ch for a 20MHz bandwidth, a distance of 10ch for a 40MHz bandwidth, a distance of 20ch for an 80MHz bandwidth, and a distance of 40ch for a 160MHz bandwidth. The STR-enabled channel distance may consist of only the distance for a 20 MHz bandwidth, or may additionally include the distance for a bandwidth not included in the above example, such as a 320 MHz bandwidth. Specific details of how the STR-enabled channel distance is included in the Association Response will be described later in the description of FIG. 6. A method for determining the channel distance will be described later in the description of FIG. 7. In this embodiment, the timing for determining each channel distance is immediately before transmitting the Association Response. The timing is not limited to the timing of transmitting the Association Response, but may also be the timing when a Probe Request is received, the timing before a Beacon is sent, or the timing when a change in the communication status is detected. Other timings include, for example, the timing when the transmission power of the AP 101 is changed, the timing when the transmission power from the STA 102 is changed, the timing when the packet loss rate in communication increases or decreases, or the timing when the packet error rate in communication increases or decreases. Alternatively, the channel distances may be determined periodically.If all channel pairs of association candidates are STR-enabled, the STR-enabled channel distance for each transmission bandwidth does not need to be notified. Alternatively, if all channel pairs are not STR-enabled, the STR-enabled channel distance for each transmission bandwidth does not need to be notified.

[0044] The Association Response sent here includes operational information determined by the AP 101 when performing Multi-Link communication with the STA 102. If the STA 102 sent an Association Request including the requested operational information in S404, the AP 101 may send an Association Response including whether or not the request is accepted.

[0045] When the STA 102 receives an Association Response, it can detect the simultaneous transmission and reception performance of the association candidate link from the AP 101's perspective based on the STR channel distance for each transmission bandwidth included in the response. Specifically, if the channels are separated by the STR channel distance for each transmission bandwidth, the AP 101 determines that simultaneous transmission and reception is possible on that channel pair. For example, suppose the association candidate links are 1ch, 5ch, and 6ch, and the STR channel distance for 20 MHz is 5. Then, for the pair of 1ch and 6ch, which are separated by 5ch, it is determined that 20 MHz can be transmitted on one link and 20 MHz can be received on the other link. On the other hand, for the pair of 1ch and 5ch, since the channel distance is less than 5ch, it is determined that 20 MHz cannot be transmitted on one link and 20 MHz cannot be received on the other link. For example, suppose the association candidate links are 1ch, 10ch, and 36ch, and the STR channel distance for 40 MHz is 10. Therefore, for the pair of 10ch and 36ch, which are separated by 26ch, it is determined that one link can transmit at 40MHz while the other link can receive at 20MHz. On the other hand, for the pair of 1ch and 10ch, since the channel distance is less than 10ch, it is determined that one link can transmit at 40MHz while the other link cannot receive at 20MHz. In this example, the receive bandwidth is fixed at 20MHz even though the transmit bandwidth is not 20MHz (it is 40MHz). Note that this receive bandwidth can also be determined by matching it to the transmit bandwidth. For example, suppose the candidate links for association are 1ch, 10ch, and 36ch, and the 40MHz STR possible channel distance is 10. Therefore, for the pair of 10ch and 36ch, which are separated by 26ch, it is determined that one link can transmit at 40MHz while the other link can receive at 40MHz. On the other hand, for the pair of 1ch and 10ch, since the channel distance is less than 10ch, it is determined that it is not possible to transmit 40MHz on one link and receive 40MHz on the other link.

[0046] The STA 102 sends a Reassociation Request to the AP 101 to change the association details determined in the Association Response (S406). For example, the Association Response in S404 associated channels 1, 5, and 10, but it determined that the 20 MHz STR available channel distance was 5, and simultaneous transmission and reception on channels 1 and 5 was not possible. To remedy this, the STA 102 sends a request to the AP 101 to reassociate channels 1, 6, and 11, for example. Alternatively, a Disassociation Request may be sent instead of a Reassociation Request. Alternatively, data transmission may be performed directly without sending a Reassociation Request. In this case, because simultaneous transmission and reception on channels 1 and 5 is not possible, synchronization control is required to prevent one channel from transmitting while the other is receiving, or control is required to detect missed packets and attempt retransmission for accurate reception. Alternatively, processing may be performed to perform communication on channel pairs that cannot be transmitted and received simultaneously, with lower priority or communication that does not require accurate reception. For example, the TID (Traffic IDentifier) ​​assignment may be changed.

[0047] 5 shows an example of the configuration of an Association Response frame sent by the AP 101 to the STA 102. The Capability Information element (501) indicates the optional functions requested or the optional functions supported by the AP itself. The Status Code element (502) indicates whether the request to which the response is directed is successful or unsuccessful. The AID element (503) indicates the association identifier assigned by the AP 101. Element 504 indicates the capability information of the channel on which the AP 101 is transmitting the Association Response frame. For example, when performing communication compliant with IEEE802.11n, an HT Capabilities element (505) is stored in the capability information. Furthermore, for example, when performing communication compliant with IEEE802.11ac, a VHT Capabilities element (506) or the like is stored, but this is not limiting.

[0048] The ML (Multi-Link) element (507) is information indicating that Multi-Link communication is supported. The ML element is not included in the Association Response frame of an AP that does not support Multi-Link communication. Furthermore, the ML element (507) is composed of an Element ID field 511 that identifies the element, a Length field 512 that indicates the data length of the element, and information specific to the element. The element-specific information is composed of Common Info 513 that contains information common to all links, and Per Link Info 514 that contains information specific to each link.

[0049] Reference numerals 521 to 525 indicate information contained in Common Info. MLD MAC Address 521 indicates the MLD (Multi-Link Device) MAC (Medium Access Control) address of the AP 101. 20MHz STR Distance 522 indicates the STR-enabled channel distance, which is the distance between channels that are STR-enabled channels with a transmission bandwidth of 20MHz. For example, if a value of 5 is stored, this indicates that if two channels are 5 channels or more apart, the AP 101 can transmit at 20MHz on one channel and receive at 20MHz on the other channel. 40MHz STR Distance 523 indicates the distance between channels that are STR-enabled channels with a transmission bandwidth of 40MHz. For example, if a value of 10 is stored, this indicates that if two channels are 10 channels or more apart, the AP 101 can transmit at 40MHz on one channel and receive at 20MHz on the other channel. 80MHz STR Distance 524 indicates the distance between channels that are STR-enabled for an 80MHz transmission bandwidth. For example, if a value of 20 is stored, this indicates that if two channels are 20 channels or more apart, the AP 101 can transmit at 80MHz on one channel and receive at 20MHz on the other channel. Other bandwidth ranges, such as 160MHz STR Distance, may also be used. Alternatively, information about high bandwidths not supported by the AP 101 may be omitted. Note that although the distance between channels (ch) is indicated here, the distance between frequencies (Hz) may also be indicated. Note that the receive bandwidth during simultaneous transmission and reception is fixed at 20MHz here, but it may also be the same as the transmit bandwidth. In other words, it is possible to transmit at a 40MHz bandwidth and receive at a 40MHz bandwidth (the same applies to 80MHz and 160MHz).

[0050] By including this information in the Association Response frame, the AP 101 can notify the STA 102 that it supports Multi-Link communication and the STR-enabled channel distance for each transmission bandwidth. The field names and bit positions and sizes are not limited to this example, and similar information may be stored with different field names, in different orders, or with different sizes.

[0051] 6 shows a flowchart for determining the STR-enabled channel distance in 20 MHz transmission by the AP 101. This flowchart is realized by the processor of the control unit 202 of the AP 101 executing a program stored in the storage unit 201.

[0052] First, the AP 101 searches for pairs of Ch[2] and subsequent Ch[1] in order until it finds a pair that allows STR (S601). Here, Ch[n] refers to the nth channel, starting from the smallest frequency, among association candidate channels that are capable of communication in a 20 MHz bandwidth. In this embodiment, the association candidate channels are 1ch, 5ch, 10ch, 36ch, 40ch, 64ch, and 100ch. For example, Ch[1] is 1ch, and Ch[7] is 100ch. In this case, the pair of 1ch and 5ch is checked to see if STR is possible, and if not, the pair of 1ch and 10ch is checked to see if STR is possible, and so on up to the pair of Ch[1] and Ch[7]. The method for determining whether a given channel pair is STR-able in 20MHz transmission is shown in FIG. 7, which will be described later. In this embodiment, it is assumed that 1ch and 10ch are determined to be STR-able.

[0053] Next, the AP 101 determines whether a channel pair capable of STR was found in S601 (S602). If a channel pair was found, the process proceeds to S603. If a channel pair was not found, the AP 101 determines that there is no STR channel distance at 20 MHz, or that the distance is an unrealistically large value, and ends this flow. In this embodiment, a pair of 1ch and 10ch was found, so the process proceeds to S603.

[0054] Next, set the found STR-possible channel pair as Ch[x] and Ch[y] (where x < y) (S603). In this embodiment, x = 1 and y = 3.

[0055] Next, set i = x (S604). In this embodiment, i = 1.

[0056] Next, AP101 determines whether Ch[i + 2] exists as an Association candidate channel and is a channel capable of 20 MHz communication. If it exists, proceed to S606. If it does not exist, end this flow with (Ch[y] - Ch[x]) as the STR-possible channel distance at 20 MHz. In this embodiment, since i = 1, Ch[3] exists as 10ch, so proceed to S606.

[0057] Next, set i = i + 1 and name it j = i + 2 (S606). In this embodiment, i = 2 and j = 3.

[0058] Next, AP101 searches in order for the pairs of Ch[j] and later and Ch[i] until an STR-possible pair is found (S607). In this embodiment, first check whether the pair of Ch[2] and Ch[3], that is, 5ch and 10ch, is STR-possible. If not, check whether the pair of Ch[2] and Ch[4], that is, 5ch and 36ch, is STR-possible, and check this in order up to the pair of Ch[2] and Ch[7]. Assume that in this embodiment, Ch[2] and Ch[4] are determined to be STR-possible.

[0059] Next, AP101 determines at S608 whether a channel pair that can be STR is found at S607 and whether the channel distance of that pair is less than (Ch[y] - Ch[x]). If it is found and less than (Ch[y] - Ch[x]), it proceeds to S609. If not found, or if found but greater than or equal to (Ch[y] - Ch[x]), it proceeds to S605. In this embodiment, since the channel distance of the channel found at S607 is (Ch[4] - Ch[2]) = 36 - 5 = 31 and (Ch[y] - Ch[x]) = 10 - 1 = 9, it proceeds to S605 with i = 2 remaining. By proceeding through S605 and subsequent steps again with i = 2 remaining, it will search for a channel pair that can be STR and has a closer channel distance, specifically Ch[3] = 10. By proceeding through S605 and subsequent steps again with the updated i remaining, it will search for a channel pair that can be STR and has a closer channel distance.

[0060] Next, AP101 sets the channel pair that can be STR and has a closer channel distance, found at S608, as Ch[x], Ch[y] (where x < y) at S609). In this embodiment, assume that finally Ch[1] and Ch[3] are determined to be the channel pair that can be STR and has the closest channel distance. However, in this case, since this channel pair has already been identified at S603, it does not proceed to S609. [[ID=*]]

[0061] Finally, AP101 determines (S610) the channel distance of the found channel pair that can be STR and has the closest channel distance as the STR - possible channel distance at 20 MHz, and ends this flow.

[0062] Although this flowchart has been described with a focus on transmission with a 20 - MHz bandwidth, the STR - possible channel distance can be determined in a similar way for 40 MHz, 80 MHz, etc. In the case of determining the STR - possible channel distance between a total 160 - MHz bandwidth divided into 80 MHz and 80 MHz and another channel, it can be determined by only looking at the 80 MHz that is closer to the other channel. Similarly, for other divided bandwidths, the STR - possible channel distance can be determined.

[0063] 7 shows a flowchart for determining whether STR is possible when transmitting at 20 MHz on the pair of channel A and channel B in AP 101. This flowchart is implemented by the processor of control unit 202 of AP 101 executing a program stored in storage unit 201.

[0064] First, the AP 101 detects the amount of wireless noise (B) received by the AP 101 on channel B when the AP 101 transmits a wireless frame at 20 MHz on channel A (S701). The unit of this wireless noise amount is, for example, dBm. The processing of S701 may detect the amount of wireless noise at a timing when some wireless frame transmission is necessary, or may transmit a dummy frame (a frame whose data content has no meaning) on ​​channel A to detect the amount of wireless noise.

[0065] Next, when the STA 102 transmits a wireless frame at 20 MHz on channel B, the AP 101 detects the RSSI (Received Signal Strength Indicator) (B) received by the AP 101 on channel B at 20 MHz (S702). The unit of this RSSI is, for example, dBm. In the process of S702, the RSSI may be detected when some wireless frame transmission is received, or the STA 102 may be requested in advance to transmit a dummy frame on channel B in order to detect the amount of wireless noise.

[0066] Next, AP 101 detects the amount of wireless noise (A) received by AP 101 on channel A when AP 101 transmits a wireless frame at 20 MHz on channel B (S703). The processing of S703 may detect the amount of wireless noise at a timing when some wireless frame transmission is necessary, or may transmit a dummy frame on channel B to detect the amount of wireless noise.

[0067] Next, when the STA 102 transmits a wireless frame at 20 MHz on channel A, the AP 101 detects the RSSI(A) received by the AP 101 on channel A at 20 MHz (S704). The process of S704 may detect the RSSI when some wireless frame transmission arrives, or may request the STA 102 in advance to transmit a dummy frame on channel A to detect the amount of wireless noise.

[0068] Next, the AP 101 determines whether (RSSI(A) - radio noise amount (A)) and (RSSI(B) - radio noise amount (B)) are each equal to or greater than a predetermined value (S705). If they are equal to or greater than the predetermined value, the process proceeds to S706. If they are less than the predetermined value, the process proceeds to S707. The predetermined value here may be a fixed value, or may be determined appropriately based on the communication state. For example, if the link rate on channel A is higher than a predetermined rate, the predetermined value used for comparison with (RSSI(A) - radio noise amount (A)) is set higher. This is because a higher link rate requires a higher SNR (Signal-to-noise Ratio) for high-quality communication. Alternatively, the determination may be made based on only either the RSSI or the radio noise amount. For example, it may be determined whether RSSI(A) and RSSI(B) are each equal to or greater than a predetermined value, or whether radio noise amount (A) and radio noise amount (B) are each less than a predetermined value.

[0069] Next, in S706, the AP 101 determines that the pair of channel A and channel B is STR-enabled, and ends this flow. Also, in S707, the AP 101 determines that the pair of channel A and channel B is not STR-enabled, and ends this flow.

[0070] The above describes the flowchart for determining whether STR is possible for a pair of channels A and B when transmitting at 20 MHz. The same flow applies when transmitting at 40 MHz or 80 MHz, except that the wireless bandwidth for transmission is changed to 40 MHz or 80 MHz, but the wireless bandwidth for reception is 20 MHz. Alternatively, the wireless bandwidth may be set to match the wireless bandwidth for transmission, or the bandwidth of the association candidate. Since a larger wireless bandwidth requires less SNR for high-quality communication, the predetermined value may be changed accordingly.

[0071] As described above, in this embodiment, the AP 101 transmits an Association Response including its own STR-capable channel distance for each wireless bandwidth. This allows the STA 102 to estimate which channel pairs are STR-capable and which are not in STR-capable in multi-link communication. For the purpose of efficient communication, the STA 102 can change the channel being used, establish a new channel, transmit high-priority data on an STR-capable channel, and so on. Furthermore, in this embodiment, the AP 101 notifies the STA 102 of the STR-capable channels for each wireless frequency bandwidth, but this is not limiting; the STA 102 may also notify the AP 101.

[0072] In this embodiment, the STR-enabled channel is included in the Association Response, but this is not limiting. For example, it may be included in management frames such as Beacon, Probe Request, Probe Response, Association Request, Authentication, and Action.

[0073] Example 2 In the first embodiment, the AP 101 measures the amount of wireless noise and RSSI while communicating with the STA 102, determines the STR-enabled channel distance based on the measured values, and notifies the STA 102. In this embodiment, a form will be described in which the amount of wireless noise related to transmission, among the amount of wireless noise, is measured and stored in advance, and the STR-enabled channel distance is determined based on the amount of wireless noise that has been stored while communicating with the STA 102.

[0074] The parts described with reference to FIGS. 4 to 6 are the same as those in the first embodiment, and therefore the description thereof will be omitted.

[0075] FIG. 8 is a flowchart showing a process in which the AP 101 detects transmission noise during 20 MHz transmission for the pair of channels A and B before communicating with the STA 102. This flowchart is realized by the processor of the control unit 202 of the AP 101 executing a program stored in the storage unit 201.

[0076] First, the AP 101 determines whether there are any transmission powers for which the amount of transmission noise has not yet been detected in S803 to S804 (described later) (S801). If there are, the process proceeds to S802. If there are no transmission powers, the process ends this flow. Because the AP 101 is not yet communicating with the STA 102, it is assumed that the transmission power to the STA 102 has not been determined, and it is necessary to measure the amount of transmission noise in advance at all candidate transmission powers. Alternatively, if the transmission power to the STA 102 has been determined in advance, S801 may be skipped and the process may proceed to S802.

[0077] Next, the AP 101 sets the transmission power in the wireless LAN control unit 301 to the transmission power value determined in S801 for which the amount of transmission noise has not yet been detected (S802).

[0078] Next, when AP 101 transmits a wireless frame at 20 MHz on channel A, AP 101 detects the amount of transmission noise (B) received by AP 101 on channel B and records this together with the transmission power in storage unit 306 (S803). The unit of this transmission noise is, for example, dBm. The processing of S803 may detect the amount of wireless noise at a timing when some wireless frame transmission is necessary, or may transmit a dummy frame on channel A to detect this amount of wireless noise.

[0079] Next, when AP 101 transmits a wireless frame at 20 MHz on channel B, AP 101 detects the amount of transmission noise (A) received by AP 101 on channel A and records this together with the transmission power in storage unit 306 (S804). The unit of this transmission noise amount is, for example, dBm. The processing of S804 may detect the amount of wireless noise at a timing when some wireless frame transmission is necessary, or may transmit a dummy frame on channel A to detect this amount of wireless noise.

[0080] This flow may be executed after AP101 is powered on, or before AP101 reaches the user, for example, before it is shipped from the factory, or the detection results of another similar device may be copied and stored.

[0081] 9 is a flowchart for determining whether STR is possible when transmitting at 20 MHz on the pair of channel A and channel B in AP 101. This flowchart is implemented by the processor of control unit 202 of AP 101 executing a program stored in storage unit 201.

[0082] First, the AP 101 detects from the storage unit 306 the amount of transmission noise (B) received by the AP 101 on channel B when the AP 101 transmits a wireless frame at 20 MHz on channel A (S901). The transmission power associated with the amount of transmission noise (B) is selected to match the transmission power currently set in the AP 101. Alternatively, the transmission power associated with the amount of transmission noise (B) may be a value closest to the transmission power currently set in the AP 101, or the smallest value exceeding the transmission power currently set in the AP 101.

[0083] Next, the AP 101 detects the amount of stationary noise (B) received by the AP 101 on channel B at a timing other than when the AP 101 transmits a wireless frame at 20 MHz on channel A (S902).

[0084] Next, when the STA 102 transmits a wireless frame at 20 MHz on channel B, the AP 101 detects the RSSI (Received Signal Strength Indicator) (B) received by the AP 101 on channel B at 20 MHz (S702).

[0085] Next, AP 101 detects from storage unit 306 the amount of transmission noise (A) received by AP 101 on channel A when AP 101 transmits a wireless frame at 20 MHz on channel B (S904). The amount of transmission noise (A) associated with the amount of transmission noise (A) is selected to match the transmission power currently set in AP 101. Alternatively, the transmission power associated with the amount of transmission noise (A) may be a value closest to the transmission power currently set in AP 101, or the smallest value exceeding the transmission power currently set in AP 101.

[0086] Next, the AP 101 detects the amount of stationary noise (A) received by the AP 101 on channel A at a timing other than when the AP 101 transmits a wireless frame at 20 MHz on channel B (S905).

[0087] Next, when the STA 102 transmits a wireless frame at 20 MHz on channel A, the AP 101 detects the RSSI (Received Signal Strength Indicator) (A) received by the AP 101 on channel A at 20 MHz (S704).

[0088] Next, the AP 101 determines whether (RSSI(A) - transmission noise amount (A) - stationary noise amount (A)) and (RSSI(B) - transmission noise amount (B) - stationary noise amount (B)) are each equal to or greater than a predetermined value (S907). If they are equal to or greater than the predetermined value, the process proceeds to S706. If they are less than the predetermined value, the process proceeds to S707. The predetermined value here may be a fixed value, or may be determined appropriately based on the communication state. For example, if the link rate on channel A is higher than a predetermined rate, the predetermined value used in comparison with (RSSI(A) - transmission noise amount (A) - stationary noise amount (A)) is set to a higher value. This is because a higher link rate requires a higher SNR for high-quality communication. For simplicity, one or more of the RSSI, transmission noise amount, or stationary noise amount may be treated as 0. For example, it may be determined whether RSSI(A) and RSSI(B) are each equal to or greater than a predetermined value, or it may be determined whether the transmission noise amount (A) and the transmission noise amount (B) are each less than a predetermined value.

[0089] S706 and S707 are the same as in the first embodiment, and therefore the explanation will be omitted.

[0090] The above is a description of the flowchart for determining whether STR is possible for a pair of channels A and B when transmitting at 20 MHz. The same flow applies when transmitting at 40 MHz or 80 MHz, but the wireless bandwidth for reception is changed to 40 MHz or 80 MHz, with 20 MHz used as the wireless bandwidth for reception. Alternatively, the wireless bandwidth may be set to match the wireless bandwidth for transmission, or the bandwidth of the association candidate. It may be set to the maximum bandwidth or the minimum bandwidth of the association candidate. Since a larger wireless bandwidth requires less SNR for high-quality communication, the specified value may be changed accordingly.

[0091] As described above, in this embodiment, the AP 101 transmits an Association Response including the STR-capable channel distance for each wireless bandwidth, determined based on the amount of transmission noise measured before communicating with the STA 102. This allows the STA 102 to estimate which channel pairs are STR-capable and which are not in STR-capable in multi-link communication. For the purpose of efficient communication, the STA 102 can change the channel being used, establish a new channel, transmit high-priority data on an STR-capable channel, and so on. Furthermore, in this embodiment, the AP 101 notifies the STA 102 of the STR-capable channels for each wireless frequency bandwidth, but this is not limited thereto; the STA 102 may also notify the AP 101.

[0092] In this embodiment, the STR-enabled channel is included in the Association Response, but this is not limiting. For example, it may be included in management frames such as Beacon, Probe Request, Probe Response, Association Request, Authentication, and Action.

[0093] (Other Examples) The above-described embodiments are merely examples, and the technical scope of the present invention is not limited to these, and the present invention includes various modifications in addition to the above-described embodiments. In the above-described embodiments, the IEEE802.11be standard was used as an example of a wireless LAN standard, but the present invention can also be applied to various standards including legacy standards and successor standards of the IEEE802.11 series (IEEE802.11x), as well as other wireless standards of the same type.

[0094] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions. [Explanation of symbols]

[0095] 100 Network 101 AP 102 Station 103 Multi-Link

Claims

1. A communication device conforming to the IEEE (Institute of Electrical and Electronics Engineers) 802.11 series standard, capable of performing multi-link communication with another communication device via a first link using a first frequency and a second link using a second frequency different from the first frequency, a transmitting means for transmitting, to the other communication device, first information relating to a difference between the first frequency and the second frequency required for STR (simultaneous transmit and receive) communication; A communication device, wherein the difference between the first frequency and the second frequency is indicated by multiplying a predetermined bandwidth by the first information.

2. A communication device as described in claim 1, characterized in that the first information is transmitted in association with the other communication device.

3. The communication device according to claim 1, wherein the first information is included in Common Info included in a Multi-Link element.

4. 4. The communication device according to claim 1, wherein the first information is a difference between a channel used by the first link and a channel used by the second link, which is required for STR communication.

5. the first frequency is a frequency used by a first frequency channel, and the second frequency is a frequency used by a second frequency channel; 5. The communication device according to claim 1, wherein a first frequency band including the first frequency channel is the same frequency band as a second frequency band including the second frequency channel.

6. the first frequency is a frequency used by a first frequency channel, and the second frequency is a frequency used by a second frequency channel; 5. The communication device according to claim 1, wherein a first frequency band including the first frequency channel is a frequency band different from a second frequency band including the second frequency channel.

7. 7. The communication device according to claim 5, wherein the first frequency band is one of a 2.4 GHz band, a 5 GHz band, a 6 GHz band, and a 60 GHz band, and the second frequency band is one of a 2.4 GHz band, a 5 GHz band, a 6 GHz band, and a 60 GHz band.

8. 8. The communication device according to claim 1, wherein the predetermined bandwidth is 20 MHz.

9. The communication device further comprises: noise imparted to the second frequency of the communication device by transmissions on the first frequency of the communication device; noise detected on the second frequency of the communication device when the communication device is not transmitting using the first frequency; and a transmission power detected at the second frequency of the communication device due to transmission by the other communication device using the second frequency; and noise that transmission using the second frequency of the communication device imparts to the first frequency of the communication device; and noise detected on the first frequency of the communication device when the communication device is not transmitting using the second frequency; and a transmission power detected at the first frequency of the communication device due to transmission by the other communication device using the first frequency; and 9. A communication device according to claim 1, further comprising determining means for determining the difference between the first and second frequencies based on one or more of the following values:

10. noise that transmission using the first frequency of the communication device imparts to the second frequency of the communication device; and The noise that the communication device transmits using the second frequency to the first frequency of the communication device is 10. The communication device according to claim 9, wherein the information is stored in the communication device in advance.

11. noise that transmission using the first frequency of the communication device imparts to the second frequency of the communication device; and The noise that the communication device transmits using the second frequency to the first frequency of the communication device is The communication device according to claim 9, wherein the communication device performs the measurement by transmitting a radio frame.

12. A communication method for a communication device conforming to the IEEE 802.11 series standard, capable of performing multi-link communication with another communication device by a first link using a first frequency and a second link using a second frequency different from the first frequency, comprising: a transmitting step of transmitting, to the other communication device, first information relating to a difference between the first frequency and the second frequency required for performing STR (simultaneous transmit and receive) communication; A communication method, wherein the difference between the first frequency and the second frequency is indicated by multiplying a predetermined bandwidth by the first information.

13. A program for causing a computer to operate as the communication device according to any one of claims 1 to 11.

14. A communication device conforming to the IEEE 802.11 series standards that is capable of performing multi-link communication with another communication device via a first link using a first frequency and a second link using a second frequency different from the first frequency, a receiving means for receiving, from the other communication device, first information relating to a difference between the first frequency and the second frequency required for STR (simultaneous transmit and receive) communication; A communication device, wherein the difference between the first frequency and the second frequency is indicated by multiplying a predetermined bandwidth by the first information.

15. A communication device as described in claim 14, characterized in that the first information is received in association with the other communication device.

16. The communication device according to claim 14, wherein the first information is included in common info included in a multi-link element.

17. A communication device described in any one of claims 14 to 16, characterized in that the first information is the difference between the channel used by the first link and the channel used by the second link, which is necessary for STR communication.

18. The first frequency is a frequency used by a first frequency channel, and the second frequency is a frequency used by a second frequency channel; 18. The communication device according to claim 14, wherein a first frequency band including the first frequency channel is the same frequency band as a second frequency band including the second frequency channel.

19. the first frequency is a frequency used by a first frequency channel, the second frequency is a frequency used by a second frequency channel, 18. The communication device according to claim 14, wherein a first frequency band including the first frequency channel is a frequency band different from a second frequency band including the second frequency channel.

20. A communication device as described in claim 18 or 19, characterized in that the first frequency band is any one of the frequency bands of 2.4 GHz band, 5 GHz band, 6 GHz band, and 60 GHz band, and the second frequency band is any one of the frequency bands of 2.4 GHz band, 5 GHz band, 6 GHz band, and 60 GHz band.

21. A communication device described in any one of claims 14 to 20, characterized in that the predetermined bandwidth is 20 MHz.

22. A communication method for a communication device conforming to the IEEE 802.11 series standard, capable of performing multi-link communication with another communication device by a first link using a first frequency and a second link using a second frequency different from the first frequency, comprising: a receiving step of receiving, from the other communication device, first information relating to a difference between the first frequency and the second frequency required for STR (simultaneous transmit and receive) communication; A communication method, wherein the difference between the first frequency and the second frequency is indicated by multiplying a predetermined bandwidth by the first information.

23. A program for operating a computer as a communication device described in any one of claims 14 to 21.

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