COMMUNICATION DEVICE, CONTROL METHOD, AND PROGRAM

Abstract

To suppress communication overhead by properly sending FILS (Fast Initial Link Setup) Discovery frames and / or Unsolicited Probe Response frames.SOLUTION: An AP102 controls not to send FILS Discovery frames and / or Unsolicited Probe Response frames at intervals of 20 TUs (Time Units) or less when performing communication using multiple links established via multiple different channels and controls to send FILS Discovery frames and / or Unsolicited Probe Response frames at intervals of 20 TUs or less when communication using multiple links is not being performed.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to the transmission and reception of information regarding communication in wireless communication. [Background technology]

[0002] The IEEE802.11 series is known as a WLAN communication standard formulated by the IEEE (Institute of Electrical and Electronics Engineers). WLAN is an abbreviation for Wireless Local Area Network. The IEEE802.11 series standards include the IEEE802.11a / b / g / n / ac / ax standards. Patent Document 1 discloses that the IEEE802.11ax standard performs wireless communication using OFDMA (Orthogonal Frequency Division Multiple Access).

[0003] In the IEEE802.11ax standard, in order for an AP to notify a STA of wireless communication information, in addition to a Beacon frame, it can transmit a FILS Discovery frame at a shorter interval than a Beacon frame. It can also transmit an Unsolicited Probe Response frame in addition to or instead of a FILS Discovery frame.

[0004] In order to further improve throughput and frequency utilization efficiency, IEEE is considering the formulation of the IEEE802.11be standard as a new standard in the IEEE802.11 series. The IEEE802.11be standard considers multi-link communication in which one AP establishes multiple links with one STA (Station) in frequency bands such as 2.4GHz, 5GHz, and 6GHz, and communicates simultaneously. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-50133 A Summary of the Invention [Problem to be solved by the invention]

[0006] When an AP that supports multi-link communication executes multi-link communication, the AP can store information about the multi-link communication in a FILS Discovery frame or an Unsolicited Probe Response frame that it transmits. In this case, since the amount of information contained in these frames is large, depending on the frequency at which the frames are transmitted, there is a risk that the communication overhead will become large.

[0007] In view of the above problems, an object of the present invention is to reduce communication overhead by appropriately transmitting a FILS Discovery frame and / or an Unsolicited Probe Response frame. [Means for solving the problem]

[0008] In order to achieve the above object, a communication device of the present invention comprises: The first link is in the 6 GHz band with another communication device, and the second link has a different frequency channel from the first link. an establishing means for establishing a plurality of links; establishes the first link and the second link with the other communication device. If you have, In the first link Control to not transmit FILS Discovery frames and / or Unsolicited Probe Response frames at intervals of 20 TU (Time Unit) or less and a control means for , and wherein the communication device operates only on the first link. case, The control means is The FILS Discovery frame and / or Unsolicited Probe Response frame are to be transmitted at intervals of 20 TU or less. system Control 。 Effect of the Invention

[0009] According to the present invention, by appropriately transmitting a FILS Discovery frame and / or an Unsolicited Probe Response frame, it becomes possible to suppress communication overhead. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram illustrating an example of the configuration of a network in which an AP 102 participates. [Diagram 2] FIG. 2 illustrates an example of the hardware configuration of an AP 102. [Diagram 3] FIG. 2 illustrates an example of the functional configuration of an AP102. [Figure 4] 11 is a sequence diagram showing an example of a process executed when the AP 102 communicates with the STA 103 via a single link. [Diagram 5] 11 is a sequence diagram showing an example of a process executed when the AP 102 communicates with the STA 103 via a plurality of links. [Figure 6] 11 is a sequence diagram showing another example of the processing executed when the AP 102 communicates with the STA 103 via a plurality of links. [Figure 7] 1 is a flow chart illustrating the process performed by the AP 102 when performing multi-link communication or single-link communication. [Figure 8] 10 is a flowchart showing a process performed when the AP 102 performing single link communication transmits a Beacon frame. [Figure 9] 10 is a flowchart showing a process executed when an AP 102 performing multi-link communication transmits a Beacon frame. [Figure 10] 13 is a flowchart showing another process executed when the AP 102 performing multi-link communication transmits a Beacon frame. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment 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] 1 shows the configuration of a network in which an AP (Access Point) 102 according to this embodiment participates. The AP 102 is a communication device that serves to construct a network 101. The network 101 is a wireless network.

[0013] Moreover, the STA (Station) 103 is a communication device that has a role of participating in the network 101. Each communication device is compatible with the IEEE802.11be (EHT) standard and can execute wireless communication conforming to the IEEE802.11be standard via the network 101. Note that IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers. Also, EHT is an abbreviation for Extremely High Throughput. Note that EHT may be interpreted as an abbreviation for Extreme High Throughput. Each communication device can communicate in the frequency bands of 2.4 GHz, 5 GHz, and 6 GHz. The frequency bands used by each communication device are not limited to these, and a different frequency band such as the 60 GHz band may be used. Also, each communication device can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz.

[0014] The AP 102 and the STA 103 can realize multi-user (MU) communication, which multiplexes signals from multiple users, by performing OFDMA communication conforming to the IEEE802.11be standard. OFDMA communication is an abbreviation for Orthogonal Frequency Division Multiple Access. In OFDMA communication, a portion of the divided frequency band (RU, Resource Unit) is assigned to each STA so that they do not overlap, and the carriers assigned to each STA are orthogonal. Therefore, the AP can communicate with multiple STAs in parallel.

[0015] Moreover, the AP 102 and the STA 103 perform multi-link communication by establishing links via multiple frequency channels and communicating. An AP performing multi-link communication is also called an AP MLD (Multi-Link Device). Here, the frequency channel is a frequency channel defined in the IEEE 802.11 series standard, and refers to a frequency channel capable of performing wireless communication conforming to the IEEE 802.11 series standard. In the IEEE 802.11 series standard, multiple frequency channels are defined in each of the 2.4 GHz, 5 GHz, and 6 GHz frequency bands. In addition, in the IEEE 802.11 series standard, the bandwidth of each frequency channel is defined as 20 MHz. Note that a bandwidth of 40 MHz or more may be used in one frequency channel by bonding with an adjacent frequency channel. For example, the AP 102 can establish a first link 104 with the STA 103 via a first frequency channel in the 2.4 GHz band and a second link 105 via a second frequency channel in the 5 GHz band and communicate via both links. In this case, the AP 102 maintains the second link 105 via the second frequency channel in parallel with the first link 104 via the first frequency channel. In this way, the AP 102 can improve the throughput of the communication with the STA 103 by establishing links with the STA 103 via multiple frequency channels. Note that the AP 102 and the STA 103 may establish multiple links with different frequency bands in the multi-link communication. For example, the AP 102 and the STA 103 may establish a third link in the 6 GHz band in addition to the first link 104 in the 2.4 GHz band and the second link 105 in the 5 GHz band. Alternatively, links may be established via multiple different channels included in the same frequency band. For example, the first link 104 via 1ch in the 2.4 GHz band and the second link 105 via 5ch in the 2.4 GHz band may be established. Note that links with the same frequency band and links with different frequency bands may be mixed.For example, the AP 102 and the STA 103 may establish a first link 104 via 1ch in the 2.4GHz band, a second link 105 via 5ch in the 2.4GHz band, and a third link via 36ch in the 5GHz band. By establishing multiple connections with the STA 103 in different frequency bands, the AP 102 can communicate with the STA 103 in another band even when one band is congested, thereby preventing a decrease in throughput in communication with the STA 103.

[0016] In multi-link communication, the multiple links established between the AP 102 and the STA 103 may have at least different frequency channels. Note that in multi-link communication, the channel spacing between the frequency channels of the multiple links established between the AP 102 and the STA 103 may be at least greater than 20 MHz. Note that, in this embodiment, the AP 102 and the STA 103 establish the first link 104 and the second link 105, but three or more links may be established.

[0017] When performing multi-link communication, the AP 102 constructs multiple wireless networks corresponding to the respective links. In this case, the AP 102 has multiple APs internally and operates to construct a wireless network for each of them. The APs that the AP 102 has internally may be one or more physical APs, or multiple virtual APs configured on one physical AP. When multiple links are established on a frequency channel that belongs to a common frequency band, the multiple links may use a common wireless network.

[0018] When performing multi-link communication, the AP 102 and the STA 103 divide one piece of data and transmit it to the other device via multiple links. Alternatively, the AP 102 and the STA 103 may transmit the same data via each of the multiple links, so that the communication via one link serves as a backup communication for the communication via the other link. Specifically, the AP 102 transmits the same data to the STA 103 via a first link via a first frequency channel and a second link via a second frequency channel. In this case, even if an error occurs in the communication via the first link, the STA 103 can receive the data transmitted from the AP 102 because the same data is transmitted via the second link. Alternatively, the AP 102 and the STA 103 may use different links depending on the type of frame or the type of data to be communicated. The AP 102 may transmit, for example, a management frame via the first link and transmit a data frame including data via the second link. Specifically, management frames refer to Beacon frames, Probe Request frames / Response frames, and Association Request frames / Response frames. In addition to these frames, Disassociation frames, Authentication frames, De-Authentication frames, and Action frames are also called management frames. Beacon frames are frames that report network information. Probe Request frames are frames that request network information, and Probe Response frames are the corresponding responses, providing network information. Association Request frames are frames that request a connection, and Association Response frames are the corresponding responses, indicating permission for connection or an error. Disassociation frames are frames that cut off a connection.An authentication frame is a frame that authenticates a remote device, and a de-authentication frame is a frame that interrupts authentication of a remote device and disconnects the connection. An action frame is a frame for performing additional functions other than those described above. The AP 102 and the STA 103 transmit and receive management frames that comply with the IEEE802.11 series standards. Alternatively, when transmitting data related to a captured image, for example, the AP 102 may transmit meta-information such as date, parameters at the time of capturing an image (aperture value and shutter speed), and location information via a first link, and transmit pixel information via a second link.

[0019] Also, the AP 102 and the STA 103 may be capable of performing MIMO (Multiple-Input And Multiple-Output) communication. In this case, the AP 102 and the STA 103 have multiple antennas, and one transmits different signals from each antenna using the same frequency channel. The receiving side simultaneously receives all signals arriving from multiple streams using multiple antennas, and separates and decodes the signals of each stream. In this way, by performing MIMO communication, the AP 102 and the STA 103 can communicate more data in the same time compared to when not performing MIMO communication. Also, the AP 102 and the STA 103 may perform MIMO communication in some links when performing multi-link communication.

[0020] In order to announce network information, the AP 102 may transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame in addition to a Beacon frame. FILS is an abbreviation for Fast Initial Link Setup.

[0021] The AP 102 can include information on multiple APs used by the AP itself in the RNR (Reduced Neighbor Report) element in the FILS Discovery frame. Specifically, the RNR element includes information such as the Operating Class and channel information of each AP, and the transmission timing of the Beacon frame. When the AP 102 is in multi-link operation, the AP 102 can include information on multiple APs used for multi-link in the FILS Discovery frame. Note that the FILS Discovery frame includes less information than the Beacon frame.

[0022] The AP 102 can include the same information as a normal probe response frame in the Unsolicited Probe Response frame. Unlike a normal probe response frame, the Unsolicited Probe Response frame is a frame that the AP 102 transmits autonomously at a predetermined time. The AP 102 that supports multi-link communication can include an RNR element that includes information about the multi-link of the AP 102 in the Unsolicited Probe Response frame. The RNR element includes information common to multiple links established by the AP 102.

[0023] The IEEE802.11ax standard specifies that when an AP operates in the 6 GHz band, the AP may transmit FILS Discovery frames and / or Unsolicited Probe Response frames at intervals of 20 TU. Note that TU is an abbreviation for Time Unit, and 1 TU corresponds to 1 ms. In this case, the AP will transmit FILS Discovery frames and / or Unsolicited Probe Response frames at intervals shorter than the 100 TU transmission interval of Beacon frames.

[0024] When the AP 102 establishes multiple links including the 6 GHz band and is performing multi-link communication, if these frames including information on the multi-link communication are transmitted at intervals of 20 TU, there is a risk of a decrease in communication throughput. Therefore, the AP 102 of the present embodiment suppresses a decrease in communication throughput by appropriately setting the transmission intervals of these frames based on whether multi-link communication is being performed.

[0025] Although the AP 102 and the STA 103 are described as being compatible with the IEEE 802.11be standard, they may also be compatible with at least one of the legacy standards that are standards prior to the IEEE 802.11be standard. The legacy standards are the IEEE 802.11a / b / g / n / ac / ax standards. In this embodiment, at least one of the IEEE 802.11a / b / g / n / ac / ax / be standards is called the IEEE 802.11 series standard. In addition to the IEEE 802.11 series standard, 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. OFDM stands for Orthogonal Frequency Division Multiplexing. NFC stands for Near Field Communication. UWB includes wireless USB, wireless 1394, WiNet, etc. It may also be compatible with communication standards for wired communication such as wired LAN.

[0026] Specific examples of the AP 102 include, but are not limited to, a wireless LAN router and a PC. The AP 102 may be any communication device capable of performing multi-link communication with other communication devices. The AP 102 may also be an information processing device such as a wireless chip capable of performing wireless communication conforming to the IEEE802.11be standard. Specific examples of the STA 103 include, but are not limited to, a camera, a tablet, a smartphone, a PC, a mobile phone, a video camera, and the like. The STA 103 may also be any communication device capable of performing multi-link communication with other communication devices. The STA 103 may also be an information processing device such as a wireless chip capable of performing wireless communication conforming to the IEEE802.11be standard. The network in FIG. 1 is a network configured by one AP and one STA, but the number of APs and STAs is not limited to this. The information processing device such as a wireless chip has an antenna for transmitting the generated signal.

[0027] In this embodiment, the AP 102 is an access point and the STA 103 is a station, but this is not limiting, and both the AP 102 and the STA 103 may be stations. In this case, the AP 102 is a station, but operates as a device having a role of constructing a wireless network for establishing a link with the STA 103.

[0028] 2 shows an example of a hardware configuration of the AP 102. The AP 102 includes 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.

[0029] The storage unit 201 is composed of one or more memories such as a ROM and a 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. As the storage unit 201, in addition to memories such as ROM and RAM, 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 may be used. Furthermore, the storage unit 201 may include multiple memories.

[0030] The control unit 202 is configured with one or more processors such as a CPU or MPU, and controls the entire AP 102 by executing a computer program stored in the storage unit 201. The control unit 202 may control the entire AP 102 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 include multiple processors such as multi-core processors, and the entire AP 102 may be controlled by the multiple processors.

[0031] Furthermore, the control unit 202 controls the functional unit 203 to execute predetermined processes such as wireless communication, imaging, printing, projection, etc. The functional unit 203 is hardware that enables the AP 102 to execute predetermined processes.

[0032] 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 by the output unit 205 may be a display on a monitor screen, a voice output by a speaker, a vibration output, or the like. Note that both the input unit 204 and the output unit 205 may be realized by a single module, such as a touch panel. Also, the input unit 204 and the output unit 205 may be integrated with the AP 102, or may be separate from it.

[0033] The communication unit 206 controls wireless communication conforming to the IEEE802.11be standard. The communication unit 206 may control wireless communication conforming to other IEEE802.11 series standards in addition to the IEEE802.11be standard, or control wired communication such as a wired LAN. The communication unit 206 controls the antenna 207 to transmit and receive signals for wireless communication generated by the control unit 202. The AP 102 may have a plurality of communication units 206. When the AP 102 having a plurality of communication units 206 establishes a plurality of links in multi-link communication, the AP 102 establishes at least one link per communication unit 206. Alternatively, the AP 102 may establish a plurality of links using one communication unit 206. In this case, the communication unit 206 executes communication via a plurality of links by switching a frequency channel that operates in a time-division manner. Note that, when the AP 102 supports the NFC standard, the Bluetooth standard, or the like in addition to the IEEE802.11be standard, the AP 102 may control wireless communication conforming to these communication standards. In addition, when the AP 102 can perform wireless communication conforming to a plurality of communication standards, it may be configured to have a communication unit and an antenna corresponding to each communication standard separately. The AP 102 communicates data such as image data, document data, and video data with the STA 103 via the communication unit 206. The antenna 207 may be configured as a separate unit from the communication unit 206, or may be configured together with the communication unit 206 as a single module.

[0034] 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 102 has one antenna, but may have a different antenna for each frequency band. In addition, when the AP 102 has multiple antennas, it may have a communication unit 206 corresponding to each antenna.

[0035] The STA 103 has the same hardware configuration as the AP 102 .

[0036] 3 shows an example of a functional configuration of the AP 102. The AP 102 includes a multilink control unit 301, a FILS Discovery frame generation unit 302, and an Unsolicited Probe Response frame generation unit 303. The AP 102 further includes a frame transmission interval control unit 304, a Beacon frame generation unit 305, and a frame transmission / reception unit 306.

[0037] The multi-link control unit 301 controls whether the AP 102 performs multi-link communication or single-link communication. Single-link communication is a link in which the AP 102 establishes only a single link. Whether the AP 102 performs multi-link communication may be set by the user, or may be determined by the AP 102 depending on the channel usage status.

[0038] The FILS Discovery frame generation unit 302 generates a FILS Discovery frame in accordance with the multi-link communication in the AP 102 and the frequency band used by the AP 102 .

[0039] The Unsolicited Probe Response frame generation unit 303 generates an Unsolicited Probe Response frame in accordance with the multi-link communication in the AP 102 and the frequency band used by the AP 102 .

[0040] The frame transmission interval control unit 304 controls the transmission intervals of Beacon frames, FILS Discovery frames, and Unsolicited Probe Response frames in the AP 102. The transmission interval of Beacon frames is 100 TU, and FILS Discovery frames and Unsolicited Probe Response frames are transmitted at intervals shorter than 100 TU.

[0041] The Beacon frame generating unit 305 generates a Beacon frame. The Beacon frame includes an Unsolicited Probe Responses Active subfield, which is a flag indicating whether to transmit an Unsolicited Probe Response frame. The Unsolicited Probe Responses Active subfield is included in a Neighbor Report element or an RNR element. The Beacon frame may also include an RNR element that includes information regarding multilink communication of the AP 102.

[0042] The frame transmission / reception unit 306 controls the transmission and reception of management frames, such as Beacon frames, FILS Discovery frames, and Unsolicited Probe Response frames, control frames, and data frames.

[0043] Fig. 4 shows a sequence diagram of the process executed when AP102 communicates with STA103 via a single link. In the example shown in Fig. 4, AP102 executes single-link communication. The process of this sequence is started in response to powering on AP102. Alternatively, it may be started in response to a user's instruction to AP102 to execute single-link communication. AP102 operates AP1 and executes single-link communication with STA103. Note that AP1 operates in the 6 GHz band.

[0044] AP102 transmits a Beacon frame including information about AP1 (S401). Next, since AP102 is communicating in the 6 GHz band, it transmits an Unsolicited Probe Response frame (S402). AP102 transmits the Unsolicited Probe Response frame at 20 TU intervals. When 100 TU has passed since the last time it transmitted a Beacon frame, AP102 transmits a Beacon frame again (S403).

[0045] In this way, when performing single-link communication in the 6 GHz band, the AP 102 transmits Unsolicited Probe Response frames at intervals of 20 TU between transmitting Beacon frames. The Unsolicited Probe Response frames transmitted here do not include information about multiple APs used in multi-link communication, so communication overhead is small. Therefore, the AP 102 transmits Unsolicited Probe Response frames at short intervals of 20 TU. Note that, in this figure, the AP 102 transmits Unsolicited Probe Response frames, but instead of at least one Unsolicited Probe Response frame, it may transmit a FILS Discovery frame.

[0046] Fig. 5 shows a sequence diagram of the process executed when AP102 communicates with STA103 via multiple links. In the example shown in Fig. 5, AP102 executes multi-link communication. The process of this sequence is started in response to powering on AP102. Alternatively, it may be started in response to a user's instruction to AP102 to execute multi-link communication. AP102 operates AP1 and AP2, and executes multi-link communication with STA103. Note that AP1 and AP2 operate in the 6 GHz band, and use different frequency channels.

[0047] AP102 transmits a Beacon frame using AP2 (S501). The Beacon frame transmitted in this step includes an RNR element that includes information common to the links established by AP1 and AP2. Next, AP102 transmits an Unsolicited Probe Response frame including an RNR element using AP2 (S502). AP102 transmits the Unsolicited Probe Response frame at intervals of 50 TU, which is longer than 20 TU. When 100 TU has elapsed since the previous transmission of a Beacon frame, AP102 transmits a Beacon frame again using AP2 (S503). Note that, although the case where AP102 uses AP2 has been described in this sequence, the same process may be performed using AP1.

[0048] In this way, when performing multi-link communication, the AP 102 transmits an Unsolicited Probe Response frame at an interval of 50 TU, which is longer than 20 TU, between transmitting Beacon frames. The Unsolicited Probe Response frame transmitted here contains information about a plurality of APs used in multi-link communication, which increases communication overhead. Therefore, the AP 102 transmits an Unsolicited Probe Response frame at an interval of 50 TU, which is longer than 20 TU. Note that, although the transmission interval of the Unsolicited Probe Response frame is set to 5 OTU in this sequence, it is not limited to this and may be any interval longer than 20 TU. Also, in this figure, the AP 102 transmits an Unsolicited Probe Response frame, but instead of at least one Unsolicited Probe Response frame, a FILS Discovery frame may be transmitted.

[0049] 6 shows another example of a sequence diagram of the process executed when the AP 102 communicates with the STA 103 via multiple links. In the example shown in FIG. 6, the AP 102 executes multi-link communication. The process of this sequence is started in response to the power supply of the AP 102 being turned on. Alternatively, the process may be started in response to a user's instruction to the AP 102 to execute multi-link communication. The AP 102 operates the AP 1 and the AP 2, and executes multi-link communication with the STA 103. Note that the AP 1 and the AP 2 operate in the 6 GHz band, and use different frequency channels.

[0050] AP102 transmits a Beacon frame using AP2 (S601). The Beacon frame transmitted in this step includes an RNR element that includes information common to the links established by AP1 and AP2. When 100 TU has elapsed since the previous transmission of a Beacon frame, AP102 transmits a Beacon frame again using AP2 (S602). Note that, although the case where AP102 uses AP2 has been described in this sequence, similar processing may be performed using AP1. In the example shown in this sequence, AP102 transmits Beacon frames at 100 TU intervals without transmitting an Unsolicited Probe Response frame or a FILS Discovery frame that includes an RNR element.

[0051] In this way, when performing multi-link communication, the AP 102 does not transmit an Unsolicited Probe Response frame or a FILS Discovery frame while transmitting a Beacon frame, thereby suppressing communication overhead.

[0052] FIG. 7 is a flowchart showing a process executed by the control unit 202 reading and executing a computer program stored in the storage unit 201 when the AP 102 executes multi-link communication or single-link communication.

[0053] This flowchart starts in response to power-on of the AP 102. Alternatively, it may start in response to a user's instruction to the AP 102 to start communication.

[0054] First, the AP 102 determines the operation mode of the own device to be multi-link or single-link (S701). Whether the AP 102 performs multi-link communication or single-link communication is determined by the user. Alternatively, the AP 102 may autonomously determine whether to perform multi-link communication or single-link communication based on the state of the frequency channel or frequency band, the size of data to be communicated, etc.

[0055] Next, the AP 102 determines whether an instruction to stop the AP has been received (S702). Specifically, the AP 102 determines whether an instruction to stop operation as an AP has been received from the user. If an instruction to stop has been received, the AP 102 determines Yes in this step, stops operation as an AP, and ends the processing of this flowchart. On the other hand, if an instruction to stop has not been received, the AP 102 determines No in this step, and performs the processing of S703.

[0056] The AP 102 determines whether the AP 102 is performing multi-link communication (S703). If the AP 102 is performing multi-link communication, the AP 102 determines "Yes" in this step and performs processing of S704. On the other hand, if the AP 102 is performing single-link communication, the AP 102 determines "No" in this step and performs processing of S705.

[0057] The AP 102 executes a process for transmitting a Beacon frame during multi-link operation (S704). Details of this step will be described later with reference to FIG.

[0058] If the result of S703 is No, the AP 102 executes a process for transmitting a Beacon frame during single-link operation (S705). Details of this step will be described later with reference to FIG.

[0059] After performing the process of S704 or S705, the AP 102 determines whether or not it has received an instruction to change the operation of the multilink communication (S706). Specifically, the AP 102 determines whether or not it has received an instruction to change the operation of the multilink communication from the user. Alternatively, or in addition, the AP 102 determines whether or not it has received an instruction to change the frequency channel, frequency band, mode, number of links, etc., related to the multilink communication from the user. Note that, instead of receiving these change instructions from the user, the AP 102 may autonomously change the operation based on the state of the ongoing communication, the state of the frequency channel, etc. If the AP 102 has received the change instruction or has determined that it will autonomously change the operation, it determines Yes in this step and performs the process of S701 again. On the other hand, if the AP 102 has not received the change instruction or has determined that it will not autonomously change the operation, it determines No in this step and performs the process of S702.

[0060] As shown in FIG. 7, the AP 102 switches the transmission process of the Beacon frame based on whether it is performing multi-link communication or single-link communication.

[0061] In this flowchart and in Figures 8 to 10 described later, processes other than the transmission process of the Beacon frame, the Unsolicited Probe Response frame, and the FILS Discovery frame are omitted, but this is not limited to this. The AP 102 may perform processes such as transmission and reception of data frames, other management frames, and control frames in parallel with or between each step of Figures 7 to 10.

[0062] FIG. 8 is a flowchart showing a process that is executed by the control unit 202 reading and executing a computer program stored in the storage unit 201 when the AP 102 performing single-link communication transmits a Beacon frame.

[0063] The process of this flowchart starts in response to the AP 102 starting the process of S705 in FIG.

[0064] First, the AP 102 includes in a Beacon frame a Neighbor Report element or an RNR element in which the Unsolicited Probe Responses Active subfield is set to 1 (S801). This enables the AP 102 to announce that it will transmit an Unsolicited Probe Response frame.

[0065] Next, the AP 102 sets the transmission interval for transmitting the Unsolicited Probe Response frame to 20 TU or less (S802). Since the AP 102 is performing single-link communication, information on multiple APs related to multi-link communication is not included in the Unsolicited Probe Response frame. Therefore, even if the transmission interval for the Unsolicited Probe Response frame is set to 20 TU or less, the communication overhead is small.

[0066] Next, the AP 102 judges whether the transmission interval of the Unsolicited Probe Response frame has elapsed since the last transmission of the Beacon frame or the Unsolicited Probe Response frame (S803). If the transmission interval has not elapsed, the AP 102 judges No in this step and performs the process of S807. If the transmission interval has elapsed, the AP 102 judges Yes in this step and performs the process of S804. The AP 102 judges whether the transmission interval of the Beacon frame has elapsed since the last transmission of the Beacon frame (S807). The transmission interval of the Beacon frame of the AP 102 is preset in the AP 102 as 100 TU. Alternatively, an arbitrary transmission interval may be set by the user. If the Beacon transmission interval has elapsed, the AP 102 judges Yes in this step and performs the process of S806. Alternatively, if the Beacon transmission interval has not elapsed, the AP 102 judges No in this step and performs the process of S803 again.

[0067] The AP 102 determines whether the Beacon frame transmission interval has elapsed since the last time the AP 102 transmitted a Beacon frame (S804). If the Beacon transmission interval has elapsed, the AP 102 determines Yes in this step and performs processing in S806. Alternatively, if the Beacon transmission interval has not elapsed, the AP 102 determines No in this step and performs processing in S805.

[0068] The AP 102 transmits an Unsolicited Probe Response frame (S805). After completing the process of S805, the AP 102 performs the determination of S803 again.

[0069] On the other hand, if the result of the determination in S804 is Yes, the AP 102 transmits a Beacon frame (S806). After performing the process of this step, the AP 102 ends the process of this flowchart.

[0070] 8, an Unsolicited Probe Response frame is transmitted, but the present invention is not limited to this and an FILS Discovery frame may be transmitted instead. In this case, the AP 102 skips the process of S801.

[0071] FIG. 9 is a flowchart showing a process that is executed by the control unit 202 reading and executing a computer program stored in the storage unit 201 when the AP 102 performing multi-link communication transmits a Beacon frame.

[0072] The process of this flowchart starts in response to the AP 102 starting the process of S704 in FIG.

[0073] The process of S901 is similar to the process of S801 in FIG.

[0074] Next, the AP 102 judges whether the Beacon frame size is larger than a predetermined threshold when the RNR element including information common to a plurality of links used in multi-link communication is included (S902). Alternatively, the AP 102 judges whether the number of established links is larger than a predetermined threshold in this step. If the AP 102 judges that the Beacon frame size is larger than the predetermined threshold or the number of established links is larger than the predetermined threshold, the AP 102 judges Yes in this step and performs processing of S903. On the other hand, if the AP 102 judges that the Beacon frame size is equal to or smaller than the predetermined threshold or the number of established links is equal to or smaller than the predetermined threshold, the AP 102 judges No in this step and performs processing of S904. Note that, in this step, whether the Beacon frame size or the number of links is judged may be selected by the user or may be preset in the AP 102. Alternatively, the AP 102 may judge both, and if at least one of the judgment results is Yes, the AP 102 may judge Yes in this step. The predetermined threshold value for the Beacon frame and the predetermined threshold value for the number of links may both be preset in the AP 102 or may be set by the user.

[0075] The AP 102 sets the transmission interval of the Unsolicited Probe Response frame to a value greater than 20TU (S903). The transmitted Unsolicited Probe Response frame includes an RNR element that includes information common to a plurality of links used in multi-link communication.

[0076] On the other hand, if the AP 102 determines No in S902, it sets the transmission interval of the Unsolicited Probe Response frame to a value equal to or less than 20 TU (S904). The transmitted Unsolicited Probe Response frame includes an RNR element that includes information common to multiple links used in multi-link communication.

[0077] The processes in S905 to S909 are similar to the processes in S803 to S807 in FIG.

[0078] 9, when the Beacon frame size is equal to or larger than a predetermined threshold, or when the number of links is equal to or larger than a predetermined threshold, the AP 102 sets the transmission interval of the Unsolicited Probe Response frame to be greater than 20 TU. This makes it possible to suppress the transmission frequency of the Unsolicited Probe Response frame including the RNR element that includes information common to multiple links used in multi-link communication, and suppress communication overhead.

[0079] 9, an Unsolicited Probe Response frame is transmitted, but the present invention is not limited to this and an FILS Discovery frame may be transmitted instead. In this case, the AP 102 skips the process of S901.

[0080] Also, the determination in S902 may be skipped and the process in S903 may be performed. In this case, the AP 102 sets the transmission interval of the Unsolicited Probe Response frame to be greater than 20 TU based on the fact that the AP 102 is performing multi-link communication.

[0081] Fig. 10 is a flowchart showing a process different from that shown in Fig. 9, which is executed by the control unit 202 reading and executing a computer program stored in the storage unit 201 when the AP 102 performing multi-link communication transmits a Beacon frame. In the process shown in the flowchart in Fig. 10, the AP 102 does not transmit any Unsolicited Probe Response frames.

[0082] The process of this flowchart starts in response to the AP 102 starting the process of S704 in FIG.

[0083] First, the AP 102 includes in a Beacon frame a Neighbor Report element or an RNR element in which the Unsolicited Probe Responses Active subfield is set to 0 (S1001). This enables the AP 102 to announce that it will not transmit an Unsolicited Probe Response frame.

[0084] In S1002, the AP 102 performs the same process as in S804 in Fig. 8. If the AP 102 determines No in S1002, it performs the process of S1002 again. On the other hand, if the AP 102 determines Yes in S1002, it performs the process of S1003.

[0085] In S1003, the AP 102 performs the same process as in 806 of FIG.

[0086] As described above, as shown in FIG. 10, by not transmitting an Unsolicited Probe Response frame when multi-link communication is being performed, communication overhead can be reduced.

[0087] The AP 102 may suppress transmission of the FILS Discovery frame instead of the Unsolicited Probe Response frame. In this case, the AP 102 skips the process of S1001 in this flow.

[0088] The AP 102 may be a device capable of selecting the process of FIG. 9 or the process of FIG. 10 as a mode, or may be a device capable of executing only one of the processes.

[0089] 7 to 10 may be executed when the AP 102 operates only in the 6 GHz band, and may not be executed when the AP 102 operates in the 2.4 GHz band and / or the 5 GHz band. Alternatively, the AP 102 may execute the processes in FIGS. 7 to 10 based on the fact that at least one AP operates in the 6 GHz band.

[0090] At least a part or all of the flowcharts of AP102 shown in Figures 7 to 10 may be realized by hardware. When realizing by hardware, for example, a specific compiler may be used to generate a dedicated circuit on an FPGA from a computer program for realizing each step, and this may be used. FPGA is an abbreviation for Field Programmable Gate Array. Also, a gate array circuit may be formed in the same manner as an FPGA, and realized as hardware. Also, it may be realized by an ASIC (Application Specific Integrated Circuit).

[0091] The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a 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 implements one or more of the functions. [Explanation of symbols]

[0092] 101 Network 102 AP 103 STA 104,105 Links

Claims

1. 1. A communication device, comprising: an establishment means for establishing a plurality of links including a first link in the 6 GHz band with another communication device and a second link having a frequency channel different from that of the first link; and a control means for controlling not to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval of 20 TU (Time Unit) or less in the first link when the establishing means has established the first link and the second link with the other communication device, When the communication device operates only on the first link, the control means controls the communication device to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval of 20 TU or less on the first link. A communication device comprising:

2. 2. The communication device according to claim 1, wherein the control means performs control so as not to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame in the first link when the establishing means has established the first link and the second link with the other communication device.

3. 2. The communication device according to claim 1, further comprising a transmitting means for transmitting a Beacon frame including an Unsolicited Probe Responses Active subfield having a value of 0 set thereto when the establishing means has established the first link and the second link with the other communication device.

4. 2. The communication device according to claim 1, wherein the control means controls the transmission of a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval greater than 20 TU in the first link when the establishment means has established the first link and the second link with the other communication device.

5. 5. The communication device according to claim 4, further comprising a transmitting means for transmitting a Beacon frame including an Unsolicited Probe Responses Active subfield in which a value of 1 is set.

6. a first determination means for determining whether a size of a Beacon frame transmitted by the transmission means is larger than a predetermined threshold value when the establishment means has established the first link and the second link with the other communication device; the control means performs control so as to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval greater than 20 TUs when the first determination means determines that the size of the Beacon frame is greater than the predetermined threshold; 6. The communication device according to claim 5, wherein when the first determination means determines that the size of the Beacon frame is equal to or smaller than the predetermined threshold, the communication device controls to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval of 20 TU or less.

7. a second determination means for determining whether or not a number of links established by the establishment means is greater than a predetermined threshold value when the establishment means has established a plurality of links including the first link and the second link with the other communication device; the control means performs control so as to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval greater than 20 TUs when the second determination means determines that the number of links is greater than the predetermined threshold; 7. The communication device according to claim 5, wherein when the second determination means determines that the number of links is equal to or less than the predetermined threshold, the communication device controls to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval of 20 TUs or less.

8. 8. The communication device according to claim 4, wherein when the establishing unit has established a plurality of links including the first link and the second link with the other communication device, the FILS Discovery frame includes information regarding a plurality of APs (Access Points) used by the communication device.

9. 9. The communication device according to claim 4, wherein, when communication is being performed using the plurality of links established by the establishing unit, an Unsolicited Probe Response frame includes an RNR (Reduced Neighbor Report) element including information common to the plurality of links.

10. 10. The communication device according to claim 1, wherein the communication device operates only in the 6 GHz band.

11. A communication device described in any one of claims 1 to 9, characterized in that the second link is a link in the 2.4 GHz band or the 5 GHz band.

12. 12. The communication device according to claim 1, wherein the communication using the plurality of links is multi-link communication conforming to the IEEE 802.11be standard.

13. A method for controlling a communication device, comprising: an establishing step of establishing a plurality of links including a first link in the 6 GHz band with another communication device and a second link having a different frequency channel from the first link; a first control step of controlling not to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval of 20 TU (Time Unit) or less in the first link when the first link and the second link are established with the other communication device in the establishing step; a second control step of controlling the communication device to transmit a FILS Discovery frame and / or an Unsolicited Probe Response frame at an interval of 20 TU or less in the first link when the communication device operates only in the first link; 13. A method for controlling a communication device, comprising:

14. A program for causing a computer to function as the communication device control method according to claim 13.

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