Communication device, communication method, and storage medium

Abstract

A communication apparatus, a communication method, and a storage medium are disclosed. When a communication apparatus transmits a frame through a multicast communication or a broadcast communication in a state where a connection with one or more other communication apparatuses has been established through a plurality of frequency channels, the communication apparatus determines a frequency channel for transmitting the frame based on whether the one or more other communication apparatuses are operating in a power save state in the plurality of frequency channels, and transmits the frame through the determined frequency channel.

Description

TECHNICAL FIELD

[0001] Aspects of the present application relate to a communication device that performs wireless communication. BACKGROUND

[0002] As a WLAN communication standard established by the Institute of Electrical and Electronics Engineers (IEEE), the IEEE 802.11 series of standards is known. WLAN is an abbreviation for wireless local area network. The IEEE 802.11 series of standards includes, for example, IEEE 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax standards.

[0003] In IEEE 802.11ax, as described in Japanese Patent Application Publication No. 2018-50133, in addition to a high peak throughput of up to 9.6 gigabits per second (Gbps), OFDMA is used to increase communication speed in a congested situation. OFDMA is an abbreviation for orthogonal frequency division multiple access.

[0004] In order to further increase throughput, a task group has been established to develop the standard IEEE 802.11be as a successor standard to IEEE 802.11ax.

[0005] In the IEEE 802.11be standard, a technique is being considered in which one access point (AP) establishes multiple links with one station (STA) through multiple different frequency channels.

[0006] In this way, in the IEEE 802.11be standard, a multi-link communication is being considered in which an AP and a STA establish connections through multiple frequency channels and perform communication in parallel.

[0007] In a case where the AP and the STA have established connections through a first frequency channel and a second frequency channel, the STA can be in a state in which it is able to perform communication through the first frequency channel but is unable to perform communication through the second frequency channel.

[0008] At this time, when the AP transmits a frame to the STA through multicast or broadcast communication, the frame is also transmitted through the second frequency channel.

[0009] Here, for example, since the frame is transmitted through the second frequency channel even by the STA operating in a power saving state, the STA can have to wastefully enter a state in which it is able to perform communication through the second frequency channel.

[0010] Further, for example, in a case where the AP and the STA have established connections through a first frequency channel and a second frequency channel, a communication situation in the second frequency channel can be poor. If a frame is also transmitted through the second frequency channel at this time, a data packet loss can occur, and it can even be necessary to retransmit the frame through the first frequency channel.

[0011] Further, in a case where the AP and the STA have established connection through the first channel, the second channel, and the third channel, for example, the first channel and the second channel can be close to each other. If frames are transmitted through the second channel at this time, such transmission can have an influence on transmission and reception of frames in the first and second channels, and thus a waste period in which frames cannot be transmitted and received through the first channel can occur.

[0012] Thus, in multi-link communication, if frames are transmitted through multicast communication or broadcast communication via all channels, the above-described problem can occur. SUMMARY

[0013] Various embodiments of the present application provide mechanisms and techniques for preventing or reducing transmission of frames through all channels of which a communication apparatus and other communication apparatuses have established connection, when the communication apparatus and the other communication apparatuses have established connection through a plurality of channels.

[0014] According to various embodiments of the present application, a communication apparatus includes: an establishing unit configured to establish connection with one or more other communication apparatuses through a plurality of channels; a determining unit configured to determine a channel for transmitting a frame, based on whether the one or more other communication apparatuses are operating in a power save state in the plurality of channels, when the communication apparatus transmits the frame through multicast communication or broadcast communication in a state where the establishing unit has established connection with the one or more other communication apparatuses through the plurality of channels; and a transmitting unit configured to transmit the frame through the channel determined by the determining unit.

[0015] According to various embodiments of the present application, a communication apparatus includes: an establishing unit configured to establish connection with one or more other communication apparatuses through a plurality of channels; a determining unit configured to determine a channel for transmitting a frame, based on communication situations of the plurality of channels, when the communication apparatus transmits the frame through multicast communication or broadcast communication in a state where the establishing unit has established connection with the one or more other communication apparatuses through the plurality of channels; and a transmitting unit configured to transmit the frame through the channel determined by the determining unit.

[0016] According to another embodiment of the present application, a communication apparatus includes an establishing unit configured to establish a connection with another communication apparatus through a first channel, a second channel, and a third channel, and a transmitting unit configured to, when the communication apparatus transmits a frame through multicast communication or broadcast communication in a state where the establishing unit has established the connection with the other communication apparatus through the first channel, the second channel, and the third channel, transmit the frame through the first channel or the second channel in a case where transmission and reception of the frame can be performed in parallel through the first channel and the second channel, and transmit the frame through the third channel in a case where transmission and reception of the frame cannot be performed in parallel through the first channel and the second channel.

[0017] Other features of the present application will become apparent from the following detailed description of illustrative embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a diagram showing a configuration of a network established by a communication apparatus according to a first exemplary embodiment.

[0019] Figure 2 is a diagram showing an example of a channel configuration of a network established by a communication apparatus according to the first exemplary embodiment.

[0020] Figure 3 is a diagram showing an example of a channel configuration of a network established by a communication apparatus according to the first exemplary embodiment.

[0021] Figure 4 is a diagram showing a hardware configuration of a communication apparatus according to the first exemplary embodiment.

[0022] Figure 5 is a diagram showing a functional configuration of a communication apparatus according to the first exemplary embodiment.

[0023] Figure 6 is a sequence diagram showing an example of a process performed by a communication apparatus and another communication apparatus when performing multi-link communication according to the first exemplary embodiment.

[0024] Figure 7 is a flowchart of a process for determining a transmission channel used when transmitting a frame according to the first exemplary embodiment.

[0025] Figure 8 is a flowchart of a process for determining completion of determination of a transmission channel used when transmitting a frame according to the first exemplary embodiment.

[0026] Figure 9 is a flowchart of a process for determining a transmission channel used when transmitting a frame according to the second exemplary embodiment.

[0027] Figure 10is a flowchart of a process for determining a transmission frequency channel used when transmitting a frame according to the third exemplary embodiment.

[0028] Figure 11 is a diagram showing an example of a configuration of a frequency channel of a network established by a communication apparatus according to the fourth exemplary embodiment.

[0029] Figure 12 is a flowchart of a process for determining a transmission frequency channel used when transmitting a frame according to the fourth exemplary embodiment.

[0030] Figure 13 is a flowchart of a process for determining a transmission frequency channel used when transmitting a frame according to the fourth exemplary embodiment.

[0031] Figure 14 is a flowchart of a process for determining a transmission frequency channel used when transmitting a frame according to the fifth exemplary embodiment. DETAILED DESCRIPTION

[0032] Various exemplary embodiments, features, and aspects of the present application will be described in detail below with reference to the accompanying drawings. Furthermore, the configurations shown in the following exemplary embodiments are merely examples, and the present application should not be construed as being limited to the configurations shown.

[0033] Figure 1 A configuration of a network established by a communication apparatus 102 according to the first exemplary embodiment is shown. The communication apparatus 102 is an access point (AP) for establishing a network 101. Furthermore, the network 101 is a wireless network.

[0034] Further, the communication apparatus 103 is a station (STA) for joining the network 101. Each of the communication apparatuses 102 and 103 is compatible with the IEEE 802.11be (EHT) standard, and is capable of performing wireless communication conforming to the IEEE 802.11be standard through the network 101. Further, IEEE is an abbreviation for Institute of Electrical and Electronics Engineers. Further, EHT is an abbreviation for Extremely High Throughput. Further, EHT can be interpreted as an abbreviation for Extreme High Throughput. Each of the communication apparatuses 102 and 103 is capable of performing communication in a frequency band of 2.4 gigahertz (GHz), 5 GHz, and 6 GHz. The frequency band used by each of the communication apparatuses 102 and 103 is not limited to these bands, and can be a different frequency band, such as 60 GHz. Further, each of the communication apparatuses 102 and 103 is capable of performing communication using a bandwidth of 20 megahertz (MHz), 40 MHz, 80 MHz, 160 MHz, and 320 MHz.

[0035] Further, each of the communication apparatuses 102 and 103 is a multi-link device (MLD). The MLD is a communication apparatus capable of performing communication with a communication partner apparatus in parallel via a plurality of frequency channels (104 and 105).

[0036] The communication apparatuses 102 and 103 are capable of realizing multi-user (MU) communication in which signals from a plurality of users are multiplexed by performing OFDMA communication conforming to the IEEE 802.11be standard. OFDMA is an abbreviation for orthogonal frequency-division multiple access. In OFDMA communication, parts of the divided frequency band (resource units (RUs)) are allocated to respective STAs in a manner not overlapping with each other, and the carriers allocated to the respective STAs are orthogonal. Thus, the AP is capable of performing communication with a plurality of STAs in parallel. Further, each of the communication apparatuses 102 and 103 is a multi-link device (MLD). The multi-link device (MLD) is a communication apparatus capable of performing communication with a communication partner apparatus in parallel via a plurality of frequency channels.

[0037] Figure 2 and Figure 3An example of a frequency channel configuration of a network established by the communication apparatus 102 is shown. The communication apparatuses 102 and 103 establish links through a plurality of frequency channels, thereby performing multi-link communication. Here, a frequency channel is a frequency channel defined by the IEEE 802.11 series standards, and refers to a frequency channel that can be used to perform wireless communication conforming to the IEEE 802.11 series standards. In the IEEE 802.11 series standards, a plurality of frequency channels are defined for each of the 2.4 GHz, 5 GHz, and 6 GHz frequency bands. Further, in the IEEE 802.11 series standards, the bandwidth of each frequency channel is defined as 20 MHz. Further, if bonding with an adjacent frequency channel is performed, a bandwidth of 40 MHz or more can be used in one frequency channel. Referring to Figure 2 , the communication apparatus 102 and the communication apparatus 103 are connected to each other through the frequency channel 1 ch (201) and the frequency channel 48 ch (202). Referring to Figure 3 , the communication apparatus 102 and the communication apparatus 103 are connected to each other through the frequency channel 1 ch (301), the frequency channel 2 ch (302), and the frequency channel 48 ch (303). In this way, the communication apparatus 102 establishes links with the communication apparatus 103 using a plurality of frequency channels, thereby being able to improve the throughput of communication with the communication apparatus 103. Further, the communication apparatus 102 establishes a plurality of connections of different frequency bands with the communication apparatus 103, so that even when congestion occurs in a given frequency band, the communication apparatus 102 is able to perform communication with the communication apparatus 103 in a frequency band other than the given frequency band. Therefore, the communication apparatus 102 is able to prevent a decrease in throughput when communicating with the communication apparatus 103.

[0038] In multi-link communication, the plurality of links respectively established by the communication apparatuses 102 and 103 only need to be different at least in frequency channel. Further, in multi-link communication, the channel spacing between the frequency channels of the plurality of links respectively established by the communication apparatuses 102 and 103 only needs to be greater than at least 20 MHz.

[0039] In the case of performing multi-link communication, the communication apparatus 102 divides one piece of data into a plurality of pieces of data, and transmits the plurality of pieces of data to the communication partner apparatus through a plurality of links. Alternatively, the communication apparatuses 102 and 103 can transmit the same data through each of the plurality of links, thereby setting communication using one link as backup communication of communication using another link. Specifically, it is assumed that the communication apparatus 102 transmits the same data to the communication apparatus 103 through a first link using a frequency channel 1 ch and a second link using a frequency channel 48 ch. In this case, for example, even if an error has occurred in communication using the first link (1 ch), since the communication apparatus 102 is transmitting the same data through the second link (48 ch), the communication apparatus 103 is able to receive data transmitted from the communication apparatus 102. Alternatively, the communication apparatus 102 can use different links depending on the type of frame to be transmitted or the type of data to be transmitted. For example, the communication apparatus 102 can be configured to transmit a management frame through the first link (1 ch) and a data frame including data through the second link (48 ch). Further, the management frame specifically refers to a beacon frame, a probe request frame and a response frame, and an association request frame and a response frame. Further, in addition to these frames, a disassociation frame, an authentication frame, a deauthentication frame, and an action frame are also referred to as management frames. The beacon frame is a frame for announcing information about a network. Further, the probe request frame is a frame for requesting network information, and the probe response frame is a response to the request, and is a frame for providing network information. The association request frame is a frame for requesting connection, and the association response frame is a response to the request, and is a frame for indicating, for example, connection permission or connection error. The disassociation frame is a frame for performing disconnection. The authentication frame is a frame for authenticating a communication partner apparatus, and the deauthentication frame is a frame for interrupting authentication of a communication partner apparatus and performing disconnection. The action frame is a frame for performing an additional function other than the above-described functions. The communication apparatuses 102 and 103 transmit and receive the management frames conforming to the IEEE 802.11 series standards. Alternatively, for example, in the case of transmitting data about a captured image, the communication apparatus 102 can be configured to transmit meta information such as date and time, image capturing parameters (aperture value and shutter speed), and position information through the first link, and image information through the second link.

[0040] Further, the communication apparatuses 102 and 103 can be configured to be capable of performing multiple-input multiple-output (MIMO) communication. In this case, each of the communication apparatuses 102 and 103 includes a plurality of antennas, and one of the communication apparatuses transmits different signals from the respective antennas using the same frequency channel. The receiving-side apparatus receives all the signals received from the plurality of streams using a plurality of antennas at the same time, and separates and decodes the signals of each stream. When MIMO communication is performed in this way, the communication apparatuses 102 and 103 are able to communicate a larger amount of data in the same amount of time compared to the case where MIMO communication is not performed. Further, in the case where multi-link communication is performed, the communication apparatuses 102 and 103 can be configured to perform MIMO communication in some of the links.

[0041] Further, it is assumed that the communication apparatuses 102 and 103 are compatible with the IEEE 802.11be standard, but can be compatible with at least any one of legacy standards that are standards prior to the IEEE 802.11be standard in addition to or instead of the standard. The legacy standards are the IEEE 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax standards. Further, in the first exemplary embodiment, at least any one of the IEEE 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ax, and 802.11be standards and subsequent standards is referred to as an “IEEE 802.11 series standard”. Further, in addition to the IEEE 802.11 series standards, the communication apparatuses 102 and 103 can be compatible with other communication standards, such as NFC, UWB, Zigbee, or MBOA. Further, UWB is an abbreviation for ultra-wide band, and MBOA is an abbreviation for multi-band OFDM alliance. Further, OFDM is an abbreviation for orthogonal frequency division multiplexing. Further, NFC is an abbreviation for near-field communication. For example, UWB includes wireless universal serial bus (USB), wireless 1394, and Winet. Further, the communication apparatuses 102 and 103 can be compatible with a communication standard for wired communication, such as a wired local area network (LAN).

[0042] Specific examples of the communication apparatus 102 include a wireless LAN router and a personal computer (PC), but are not limited thereto. The communication apparatus 102 only needs to be any communication apparatus as long as it is capable of performing multi-link communication with another communication apparatus. Furthermore, specific examples of the communication apparatus 103 include a camera, a tablet, a smartphone, a PC, a mobile phone, and a video camera, but are not limited thereto. The communication apparatus 103 only needs to be a communication apparatus capable of performing wireless multi-link communication with another communication apparatus. Furthermore, although each of the networks shown in Figure 1 , Figure 2 and Figure 3 each network is a network composed of one AP and one STA, the number of APs and the number of STAs are not limited thereto.

[0043] Figure 4 A hardware configuration of the communication apparatus 102 in the first example embodiment is shown. The communication apparatus 102 includes a storage unit 401, a control unit 402, a function unit 403, an input unit 404, an output unit 405, a communication unit 406, and an antenna 407.

[0044] The storage unit 401 is configured with one or more memories, such as a ROM or a RAM, and stores computer programs for executing various operations described below and various information (for example, communication parameters for wireless communication). The ROM is an abbreviation for read-only memory, and the RAM is an abbreviation for random access memory. Furthermore, the storage unit 401 to be used includes, in addition to the memories such as the ROM and the RAM, storage media such as a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a compact disc-ROM (CD-ROM), a writable CD (CD-R), a magnetic tape, a non-volatile memory card, and a digital versatile disk (DVD). Furthermore, the storage unit 401 can include, for example, a plurality of memories.

[0045] The control unit 402 is configured with, for example, one or more processors (for example, a CPU or an MPU), and controls the entire communication apparatus 102 by executing the computer programs stored in the storage unit 401. Furthermore, the control unit 402 can be configured to control the entire communication apparatus 102 by cooperation of the computer programs stored in the storage unit 401 and an operating system (OS). Furthermore, the control unit 402 generates data or a signal (a wireless frame) to be transmitted in communication with another communication apparatus. Furthermore, the CPU is an abbreviation for central processing unit, and the MPU is an abbreviation for micro processing unit. Furthermore, the control unit 402 can be configured to include a plurality of processors (for example, a multi-core processor), and control the entire communication apparatus 102 by the plurality of processors.

[0046] Further, the control unit 402 controls the functional unit 403 to execute predetermined processing such as wireless communication, image capturing, printing, or projection. The functional unit 403 is hardware for the communication device 102 to execute the predetermined processing.

[0047] The input unit 404 performs reception of various operations performed by the user. The output unit 405 performs various output operations to the user through a monitor screen or a speaker. Here, the output operation of the output unit 405 can be, for example, display on the monitor screen, audio output through the speaker, and vibration output. Further, the input unit 404 and the output unit 405 can each be implemented by a single module such as a touch panel. Further, each of the input unit 404 and the output unit 405 can be integrated with the communication device 102, or can be separate from the communication device 102.

[0048] The communication unit 406 performs control of wireless communication conforming to the IEEE 802.11be standard. Further, the communication unit 406 can perform control of wireless communication compatible with another IEEE 802.11 series standard, or control of wired communication such as wired LAN, in addition to the IEEE 802.11be standard. The communication unit 406 controls the antenna 407 to perform transmission and reception of signals of wireless communication generated by the control unit 402. Further, in a case where the communication device 102 is compatible with standards other than the IEEE 802.11be standard, such as the NFC standard or the Bluetooth standard, the communication unit 406 can perform control of wireless communication conforming to these standards. Further, in a case where the communication device 102 is capable of performing wireless communication conforming to a plurality of communication standards, the communication device 102 can be configured to include respective communication units and antennas compatible with respective communication standards. The communication device 102 communicates data such as image data, document data, or video data with the communication device 103 through the communication unit 406. Further, the antenna 407 can be configured as a component separate from the communication unit 406, or can be configured as a single module integrated with the communication unit 406.

[0049] The antenna 407 is an antenna usable for 2.4 GHz, 5 GHz, and 6 GHz band communication. In the first exemplary embodiment, the communication device 102 includes one antenna, but can be configured to include different antennas for respective frequency bands. Further, in a case where the communication device 102 includes a plurality of antennas, the communication device 102 can include a communication unit 406 compatible with respective antennas.

[0050] Further, the communication device 103 has a similar hardware configuration to the communication device 102.

[0051] Figure 5 ​A functional configuration of the communication apparatus 102 in the first exemplary embodiment is shown. The communication apparatus 102 is configured with a capability information generating unit 501 for multi-link communication, an operation information determining unit 502 for multi-link communication, a group-addressed frame transmission channel determining unit 503, a connection processing unit 504, and a data transmission and reception unit 506.

[0052] The capability information generating unit 501 is a block that generates capability information related to multi-link communication with respect to the communication apparatus 102 itself. The communication apparatus 102 generates capability information for communicating capability information related to multi-link communication with respect to the communication apparatus 102 itself to another communication apparatus. Here, the capability information refers to a frequency band, a channel, and a bandwidth that the communication apparatus 102 can use. In addition, with respect to the capability information, the communication apparatus 102 can communicate capability information with respect to the communication apparatus 102 itself to another communication apparatus, or can receive capability information with respect to a communication partner apparatus only from another communication apparatus.

[0053] The operation information determining unit 502 is a block that determines operation information with respect to multi-link communication with a communication partner apparatus based on capability information related to multi-link communication with respect to the communication apparatus 102 itself. The operation information with respect to multi-link communication refers to, for example, a channel and a bandwidth used for multi-link communication between the communication apparatuses 102 and 103. With respect to the operation information, the communication apparatus 102 can be configured to communicate the determined operation information to the communication partner apparatus, or can be configured not to communicate the determined operation information to the communication partner apparatus.

[0054] The group-addressed frame transmission channel determining unit 503 is a block that determines a channel for transmitting a group-addressed frame. The group-addressed frame transmission channel determining unit 503 determines a channel for transmitting a group-addressed frame based on information related to connection of a channel obtained from the capability information generating unit 501 or the connection processing unit 504. Here, a group-addressed frame refers to a frame that includes a media access control (MAC) address in which a group bit of a destination address (DA) included in a MAC frame is "1". For example, a broadcast frame such as a beacon frame is a type of group-addressed frame because its group bit is "1". In addition, a multicast frame is also a group-addressed frame because its group bit is also "1". The group-addressed frame is transmitted by multicast communication or broadcast communication.

[0055] The connection processing unit 504 is a block that performs processing for causing the communication apparatus 103 as a STA to join a network established by the communication apparatus 102. Specifically, for example, the connection processing unit 504 causes the communication apparatus 102 to transmit an association response frame as a response to an association request, which is a connection request received from the communication apparatus 103. Further, the communication apparatus 102 can include a connection processing unit 504 corresponding to each of a plurality of links for which the communication apparatus 102 itself establishes a connection, or can use a single connection processing unit 504 in a time-sharing manner.

[0056] The data transmission and reception unit 506 is a block that performs transmission and reception of data frames in the multi-link communication based on the operation information related to the multi-link communication determined by the operation information determination unit 502.

[0057] Further, the communication apparatus 103 has a similar functional configuration to that of the communication apparatus 102, but differs in the following aspects.

[0058] The communication apparatus 103 includes a request information determination unit (not shown) instead of the operation information determination unit 502. The request information determination unit is a block that determines request information about the multi-link communication with the communication partner apparatus based on each of the capability information about the multi-link communication of the communication apparatus 103 and the communication partner apparatus. The request information about the multi-link communication refers to, for example, a frequency channel and a bandwidth that are requested to be used in the multi-link communication between the communication apparatuses 102 and 103. With regard to the request information, the communication apparatus 103 can be configured to communicate the determined request information to the communication partner apparatus, or can be configured not to communicate the determined request information.

[0059] Figure 6 is a sequence diagram that shows an example of the processing performed by the communication apparatus 102 and the communication apparatus 103 when performing the multi-link communication.

[0060] Figure 6 An example is shown in which the communication apparatus 102 and the communication apparatus 103 perform communication using a frequency channel 1 ch of a frequency band of 2.4 GHz in the first link and perform communication using a frequency channel 36 ch of a frequency band of 5 GHz in the second link.

[0061] In response to the communication apparatuses 102 and 103 both being powered on, the processing in the current sequence is started. Alternatively, at least one of the communication apparatuses 102 and 103 can start the processing in response to an instruction for starting the multi-link communication received from a user or an application. Alternatively, at least one of the communication apparatuses 102 and 103 can start the processing in response to the amount of data to be communicated to the communication partner apparatus becoming greater than or equal to a predetermined threshold value.

[0062] First, in step S601, the communication apparatus 102 transmits a beacon signal including network information about the communication apparatus 102 itself in the channel 1ch, thereby notifying the network information to the STAs in the vicinity. Specifically, the network information is a transmission interval at which the communication apparatus 102 transmits the beacon signal or an SSID of the communication apparatus 102. The SSID is an abbreviation of service set identifier. Further, the communication apparatus 102 can cause the network information to be included in the beacon signal, thereby advertising the capability information about the multi-link communication of the communication apparatus 102.

[0063] In step S602, when receiving the beacon signal transmitted by the communication apparatus 102 in the channel 1ch, the communication apparatus 103 transmits a probe request in the channel 1ch. The probe request includes an SSID of the communication apparatus 103. Further, the communication apparatus 103 transmits the capability information about the multi-link communication of the communication apparatus 103 in addition to the SSID.

[0064] Upon receiving the probe request, in step S603, the communication apparatus 102 transmits a probe response to the communication apparatus 103 in the channel 1ch as a response thereto. In a case where the communication apparatus 102 does not cause the capability information about the multi-link communication to be included in the beacon signal, the communication apparatus 102 causes the capability information to be included in the probe response, and then transmits the probe response. Alternatively, the communication apparatus 102 can be configured to cause only some of the capability information about the multi-link communication to be included in the beacon signal, and to cause the remaining capability information or all of the capability information to be included in the probe response.

[0065] When the processes in steps S601 to S603 are executed, the communication apparatuses 102 and 103 are able to exchange the respective capability information about the multi-link communication of the communication apparatuses 102 and 103.

[0066] Next, in step S604, the communication apparatus 103 transmits an association request as a connection request to the communication apparatus 102 in the channel 1ch. In this case, the communication apparatus 103 can cause the capability information about the multi-link communication to be included in the association request, and then communicate the capability information about the multi-link communication of the communication apparatus 103.

[0067] Here, the capability information on the multi-link communication is, for example, a multi-link element. Further, the communication apparatus 103 can determine the capability information to be transmitted in step S604 based on the capability information on the multi-link communication of the communication apparatus 102 acquired in at least one of steps S601 and S603. For example, even in a case where the communication apparatus 103 is capable of using a 2.4 GHz band and a 5 GHz band combined link in the multi-link communication, it is assumed that the communication apparatus 102 is compatible only with a plurality of links in the 2.4 GHz band. In this case, the communication apparatus 103 can transmit only the capability information on the establishment of a plurality of links in the 2.4 GHz band as the capability information to be transmitted in step S604. Further, although in the first example embodiment, the communication apparatus 103 transmits the capability information on the multi-link communication of the communication apparatus 103 itself in step S602, the first example embodiment is not limited to this, and the communication apparatus 103 can be configured not to transmit the capability information in step S602 and can be configured to transmit the capability information only in step S604. Alternatively, the communication apparatus 103 can cause the capability information on the multi-link communication to be included in the association request, thereby transmitting request information for making a request at the time of performing the multi-link communication instead of the capability information. The request information for the communication apparatus 103 to make a request can be represented by the capability information on the multi-link communication or can be represented by another element.

[0068] Upon receiving the association request, the communication apparatus 102 transmits an association response as a response thereto to the communication apparatus 103 in the channel 1 ch in step S605. The association response transmitted in step S605 includes operation information for performing the multi-link communication with the communication apparatus 103 determined by the communication apparatus 102. Further, in a case where the communication apparatus 103 as the STA has transmitted the association request including a request for the operation information in step S604, the communication apparatus 102 can transmit the association response including only permission or rejection of the request.

[0069] In a case where the communication apparatus 103 is capable of performing the multi-link communication using the operation information included in the association response, the communication apparatuses 102 and 103 establish a link using the channel 1 ch and then start data communication in step S606. Further, in this case, in a case where the operation information for using a link of the channel 36 ch is included in the operation information transmitted by the communication apparatus 102, the communication apparatuses 102 and 103 also establish a link using the channel 36 ch and then start data transmission in step S607.

[0070] Further, in a case where the communication apparatus 102 has displayed the permission to the communication apparatus 103 with respect to the request information transmitted in step S604 in step S605, the processing in step S606 is also performed in a similar manner. Further, in a case where the request information regarding the link using the frequency channel 36ch is also included in the request information transmitted by the communication apparatus 103 in step S604, the processing in step S607 is performed.

[0071] Although two links are established by transmitting and receiving frames in one frequency channel in the first example embodiment, the first example embodiment is not limited to this, and three or more links can be established.

[0072] Further, although the case where the communication apparatuses 102 and 103 start the multi-link communication in a state where no link has been established between the communication apparatuses 102 and 103 is described in the first example embodiment, the first example embodiment is not limited to this.

[0073] In addition to the already established links, the communication apparatuses 102 and 103 can establish a new link, and then start the multi-link communication. In this case, in a case where the communication apparatus 103 as the STA has acquired the capability information regarding the multi-link communication of the communication apparatus 102 functioning as the AP, the communication apparatus 103 can start the processing from step S604. Alternatively, in a case where the communication apparatus 102 has acquired the capability information regarding the multi-link communication of the communication apparatus 103, the communication apparatus 102 can transmit a signal for causing the communication apparatus 103 to transmit an association request, thereby enabling the communication apparatus 103 to start the processing from step S604. Alternatively, in addition to the already established multiple links, the communication apparatuses 102 and 103 can establish a new link. In these cases, the processing can be started from step S604 Figure 6 the sequence illustrated.

[0074] Further, although the case where the links using multiple frequency channels are established by transmitting and receiving frames in one frequency channel has been described in the first example embodiment, the first example embodiment is not limited to this. In a case where the multi-link communication is performed, the communication apparatuses 102 and 103 can cut off the already established links using multiple frequency channels by transmitting and receiving frames using one frequency channel.

[0075] As described above with reference to Figure 6 the communication apparatuses 102 and 103 can control the establishment or cut-off of the link in another frequency channel by transmitting and receiving frames via a given frequency channel (or link). Further, the communication apparatuses 102 and 103 can control the establishment or cut-off of the links in multiple frequency channels by transmitting and receiving frames via a given frequency channel (or link).

[0076] Further, in Figure 6In the illustrated sequence, the transmission device can cause a multiple link device (MLD) MAC address of the transmission device itself to be included in at least one of the above-described management frames transmitted in steps S601 to S605. The MLD MAC address is identification information about a communication device capable of performing multi-link communication.

[0077] Further, the transmission device can cause the MLD MAC address of the transmission device itself to be included in at least one of frames other than the management frames transmitted in steps S601 to S605.

[0078] Figure 7 is a flowchart showing a flow of processing performed by the control unit 402 executing a program stored in the storage unit 401 of the communication device 102. In the first example embodiment, an example is shown in which the AP determines a channel for transmitting a frame based on whether there is a channel on which a STA is operating in a power saving state. Here, the channel on which the STA is operating in the power saving state refers to a channel on which transmission and reception of frames cannot be performed. Further, the STA stores information indicating that the STA has entered the power saving state in a data frame, and transmits the data frame to the AP.

[0079] The present flowchart starts when the communication device 102 transmits a group addressed frame. Alternatively, the present flowchart can start when a connection configuration between the communication device 102 and another communication device has changed. The connection configuration has changed when, for example, a connection with another communication device has been started in a new link, or when a connection with another communication device has been cut off.

[0080] In step S701, the communication device 102 determines whether there is a channel on which a STA is operating in a power saving state.

[0081] Next, if it is determined in step S701 that there is a channel on which a STA is operating in a power saving state (YES in step S701), in step S702, the communication device 102 determines a channel on which a STA is not operating in a power saving state as a channel for transmitting a frame.

[0082] For ease of explanation, reference is made to Figure 2For example, if it is determined that the communication apparatus 103 is operating in the power save state in the channel 1 ch, the communication apparatus 102 determines the channel 48 ch as the channel for transmitting the frame, and thus does not transmit the frame in the channel 1 ch. If it is determined in step S701 that there is no channel in which a STA is operating in the power save state (NO in step S701), in step S703, the communication apparatus 102 determines the channel for transmitting the frame by a predetermined method. In step S703, the communication apparatus 102 can select one channel as the channel for transmitting the frame in a random manner, can select the channel for transmitting the frame based on the order of the channel numbers, or can select the channel by a different determination method. As the different determination method, for example, the communication apparatus 102 can select the channel that can be used for transmitting the frame to the largest number of STAs. Further, the communication apparatus 102 can select the channel in which the degree of congestion is low, or can select the channel while avoiding the channel of the non-STR. The channel of the non-STR will be described in detail in the third example embodiment to be described below. Further, in the case where there are a plurality of channels in which a STA is operating in the power save state, the communication apparatus 102 can also determine the channel for transmitting the frame by the above-described method.

[0083] After the channel for transmitting the frame is selected in step S702 or S703, next, in step S704, the communication apparatus 102 determines whether the determination of the channel for transmitting the frame is completed for all STAs that have established a connection with the AP. The detailed flow of step S704 will be described below with reference to Figure 8 If it is determined in step S704 that the determination of the channel for transmitting the frame is completed (YES in step S704), the communication apparatus 102 ends the processing in this flowchart. If it is determined in step S704 that the determination of the channel for transmitting the frame is not completed (NO in step S704), the communication apparatus 102 returns the processing to step S701, and thus selects the channel for transmitting the frame.

[0084] As described above, according to the first example embodiment, in the case where there is a channel in which a STA is operating in the power save state, the communication apparatus 102 can select the channel for transmitting the frame while avoiding the existing channel. Further, by avoiding the existing channel, the communication apparatus 102 can prevent or reduce the processing for starting the communication apparatus in which some functions are in the power save state and bringing such a communication apparatus into a state capable of receiving the frame.

[0085] Figure 8is a flowchart showing a flow of processing executed by the control unit 402 executing a program stored in the storage unit 401 of the communication apparatus 102. In this flowchart, the AP determines whether a group addressing frame is transmitted to a STA with which the AP has established a connection when the channel for transmitting the group addressing frame has been determined. In the first example embodiment, an example is described in which the AP determines the channel for transmitting the group addressing frame in a case where one AP and one STA have established a connection with each other through two channels. However, in a case where the AP and a plurality of STAs have established a connection with each other through a plurality of channels, some STAs can not be able to receive a frame if the AP transmits the frame in the channel determined in step S702 or S703. Therefore, the communication apparatus 102 uses this flowchart to determine whether there are no STAs that do not receive the frame.

[0086] In each channel through which the communication apparatus 102 has established a connection with the communication apparatus 103, the communication apparatus 102 has acquired the MLD MAC address of the communication apparatus 103 at the time of establishing the connection. For ease of explanation, with reference to the configuration example shown in FIG. 8B, for example, since the communication apparatus 103 is connecting to the communication apparatus 102 in channel 1 ch and channel 48 ch, the communication apparatus 102 has acquired two MLD MAC addresses from the communication apparatus 103. Figure 2

[0087] In step S801, the communication apparatus 102 acquires a first MAC address group that is the MAC address of a STA with which the communication apparatus 102 has established a connection in the determined channel for transmitting a frame. In the first example embodiment, the MLD MAC address is used as the MAC address of each STA.

[0088] Next, in step S802, the communication apparatus 102 acquires a second MAC address group that is the MAC address of all STAs with which the communication apparatus 102 has established a connection in all channels. Further, the communication apparatus 102 can not acquire the first MAC address group and the second MAC address group at the timing at which the determination of the group of channels for transmitting a frame is completed, but the communication apparatus 102 can acquire the first MAC address group in advance. For example, the communication apparatus 102 can acquire the first MAC address group when a new connection is established with a STA or when a connection with a STA is cut off.

[0089] ​Next, in step S803, the communication apparatus 102 determines whether the first MAC address group and the second MAC address group coincide with each other. If it is determined in step S803 that the first MAC address group and the second MAC address group coincide with each other (YES in step S804), in step S804, the communication apparatus 102 determines that the determination of the frequency channel for transmitting the frame has been completed. When it is determined in step S804 that the determination of the frequency channel for transmitting the frame has been completed, the communication apparatus 102 ends the determination procedure of the frequency channel for transmitting the frame without transmitting the frame in a frequency channel other than the determined frequency channel for transmitting the frame.

[0090] If it is determined in step S803 that the first MAC address group and the second MAC address group do not coincide with each other (NO in step S804), in step S805, the communication apparatus 102 determines that the determination of the frequency channel for transmitting the frame has not been completed, and then ends the determination procedure of the frequency channel for transmitting the frame.

[0091] Further, although an example in which the communication apparatus 102 determines the completion of the determination using the MAC address is described in Figure 8 the first example embodiment, the communication apparatus 102 can determine the completion of the determination using multi-link information shared by the AP and the STA at the time of establishing the connection. Further, the communication apparatus 102 can determine the completion of the determination of the frequency channel for transmitting the frame using the MAC address of the STA.

[0092] In the first example embodiment, an example in which, in a state in which the AP and the STA have established the connection through a plurality of frequency channels, the AP avoids an existing frequency channel if there is a frequency channel in which the STA operates in a power saving state is described. In the second example embodiment, an example in which, among the frequency channels in which the AP and the STA have established the connection, the AP determines the frequency channel for transmitting the frame while avoiding a frequency channel in which the degree of congestion is high is described.

[0093] Figure 9 is a flowchart showing a procedure of processing performed by the control unit 402 executing a program stored in the storage unit 401 of the communication apparatus 102.

[0094] In step S901, the communication apparatus 102 determines whether there is a frequency channel in which the degree of congestion is high among the frequency channels in which the communication apparatus 102 has established the connection with the communication apparatus 103.

[0095] If it is determined in step S901 that there is a frequency channel in which the degree of congestion is high (YES in step S901), in step S902, the communication apparatus 102 determines the frequency channel for transmitting the frame from among the frequency channels other than the frequency channel in which the degree of congestion is high. For convenience of explanation, reference is made to Figure 2For example, if it is determined that channel 1 ch is a channel with a high degree of congestion, the communication apparatus 102 determines channel 48 ch as a channel for transmitting a frame, and thus does not transmit a frame in channel 1 ch. If it is determined in step S901 that there is no channel with a high degree of congestion (NO in step S901), in step S903, the communication apparatus 102 determines a channel for transmitting a frame by a predetermined method. In step S903, the communication apparatus 102 can select one channel as a channel for transmitting a frame in a random manner, can select a channel for transmitting a frame based on the order of channel numbers, or can select a channel by a different determination method. As the different determination method, for example, the communication apparatus 102 can select a channel that can be used to transmit a frame to the largest number of STAs. Further, as with the first example embodiment, the communication apparatus 102 can select a channel in which an STA is not operating in a power save state, or can select a channel other than a channel of an STR. The channel of an STR is described in detail in the third example embodiment described below. Further, in a case where there are a plurality of channels with poor communication conditions and a high degree of congestion, the communication apparatus 102 can also determine a channel for transmitting a frame by the above-described method.

[0096] For example, with respect to the degree of congestion of a channel, the communication apparatus 102 counts the number of probe requests in which a response is received among probe requests transmitted in each channel, and thus can estimate the degree of congestion of each channel. Further, the communication apparatus 102 can count the number of beacon signals observed in each channel within a predetermined period, and thus estimate the degree of congestion of each channel. Further, the communication apparatus 102 can estimate the degree of congestion of each channel by, for example, counting the number of times of carrier sensing within a predetermined period or information exchange with another AP. Further, the communication apparatus 102 can estimate the degree of congestion of each channel by a noise level obtained in a state where no signal is received. In a case where an STA estimates the degree of congestion, the STA communicates information on the degree of congestion obtained by calculation to an AP, and the AP estimates the degree of congestion of each channel based on the information on the degree of congestion received from the STA.

[0097] The flow in step S904 and subsequent steps is similar to that described with reference to Figure 7 The flow in step S704 and subsequent steps is similar, and thus, the description thereof is not repeated here.

[0098] As described above, according to the second example embodiment, the communication apparatus 102 can determine a channel for transmitting a frame while avoiding a channel with a high degree of congestion in a link between an AP and an STA. By avoiding a channel with a high degree of congestion, the communication apparatus 102 can prevent or reduce packet loss, and prevent or reduce retransmission processing of a packet that occurs upon packet loss.

[0099] In a second example embodiment, an example is described in which, in a state in which the AP and the STA have established connection through a plurality of frequency channels, the AP determines a frequency channel for transmitting a frame while avoiding a frequency channel in which the degree of congestion is high. In a third example embodiment, an example is described in which, when the AP and the STA establish connection through a plurality of frequency channels, the AP determines a frequency channel for transmitting a frame while avoiding a frequency channel that becomes non-STR in the case where the transmission of the frame is performed. Here, STR is an abbreviation for simultaneous transmit and receive. Hereinafter, a frequency channel that is not STR is referred to as a "non-STR frequency channel".

[0100] Further, the non-STR frequency channel refers to a group of frequency channels that are in a state in which data cannot be received in a second frequency channel during the transmission of data in a first frequency channel. Further, the non-STR frequency channel also refers to a group of frequency channels that are in a state in which data cannot be transmitted in a second frequency channel during the reception of data in a first frequency channel. For example, in the case where the frequencies or channels of the first frequency channel and the second frequency channel are close to each other, these frequencies or channels can influence each other such that the first frequency channel and the second frequency channel can become unusable for transmission and reception, and can become non-STR. Further, for example, in the case where the transmission of a frame to be transmitted in the first frequency channel has a large transmission output, such a large transmission output can influence the second frequency channel such that the first frequency channel and the second frequency channel can become non-STR. In the first frequency channel and the second frequency channel that become non-STR, when the transmission and reception of data are performed, it can be necessary to perform synchronization processing of the transmission and reception in a manner that prevents the transmission and reception from overlapping each other in the respective links.

[0101] Figure 10 is a flowchart showing a flow of processing performed by the control unit 402 that executes a program stored in the storage unit 401 of the communication device 102.

[0102] In step S1001, the communication device 102 determines whether a frequency channel that becomes non-STR when the transmission of a frame is performed is present.

[0103] If, in step S1001, it is determined that a frequency channel that becomes non-STR when the transmission of a frame is performed is present (YES in step S1001), in step S1002, the communication device 102 determines a frequency channel for transmitting a frame from among the frequency channels other than the non-STR frequency channel. For example, for convenience of explanation, reference is made to Figure 3 In the case where, when the transmission of a frame is determined in the frequency channel 1 ch, the frequency channel 1 ch and the frequency channel 2 ch become non-STR, the communication device 102 determines the frequency channel 48 ch as the frequency channel for transmitting a frame, and thus does not transmit a frame in the frequency channel 1 ch and the frequency channel 2 ch.

[0104] If, in step S1001, it is determined that no channel becomes non-STR during frame transmission ("No" in step S1001), then in step S1003, the communication device 102 determines the channel for transmitting the frame using a predetermined method. In step S1003, the communication device 102 may randomly select a channel for transmitting the frame, select a channel based on the order of the number of channels, or select a channel using different determination methods. As a different determination method, the communication device 102 may select a channel capable of transmitting frames to a maximum number of STAs. Furthermore, similar to the first exemplary embodiment, the communication device 102 may select a channel where the STAs are not operating in power-saving mode, or, similar to the second exemplary embodiment, the communication device 102 may select a channel with low congestion. Furthermore, if in step S1001 it is determined that only non-STR channels exist, the communication device 102 may determine the channel for transmitting the frame from the non-STR channels using the method described above.

[0105] The process in step S1004 and subsequent steps is the same as Figure 7 The process of step S704 shown is similar to that of the subsequent steps, so it will not be described again.

[0106] Furthermore, although in the third exemplary embodiment, as described... Figure 3 The example shown illustrates a scenario where an AP and a STA have established connections via three channels, but the third exemplary embodiment is not limited to this. Furthermore, if STA1 has already established connections with the AP via channels 1ch and 10ch, and STA2 has already established connections with the AP via channels 2ch and 11ch, and a frame is to be transmitted in channel 1ch, then channel 1ch is a non-STR channel relative to the AP, but can be an STR channel relative to the STA. In this case, the communication device 102 can also determine the channel for transmitting the frame using the method described above.

[0107] As described above, according to the third exemplary embodiment, the communication device 102 is able to determine the channel for transmitting frames while avoiding channels that may become non-STRs when performing frame transmission.

[0108] Furthermore, since the communication device 102 can avoid channels that may become non-STRs, the communication device 102 can prevent or reduce the execution of synchronization processes to prevent transmission and reception from overlapping in each link.

[0109] In the first example embodiment, an example is described in which, in a state in which the AP and the STA establish a connection through a plurality of channels, if there is a channel on which the STA operates in a power save state, the AP avoids using the channel. In the fourth example embodiment, an example is described in which, when the AP prevents or reduces transmission of frames via a channel on which the STA operates in a power save state, the AP determines a channel for transmitting the frames while reducing the number of channels for transmitting the frames.

[0110] Figure 11 An example of a configuration of channels of a network established by the communication apparatus 1102 is shown.

[0111] The communication apparatuses 1102 to 1106 establish links through a plurality of channels and then perform multi-link communication. Here, a channel is a channel defined by the IEEE 802.11 series standards, and refers to a channel that can be used to perform wireless communication conforming to the IEEE 802.11 series standards. Furthermore, if bonding with an adjacent channel is performed, a bandwidth of 40 MHz or more can be used for one channel. Furthermore, the communication apparatus 1102 has the same configuration as the above-described communication apparatus 102, as shown in FIGS. 11A and 11B. Figure 4 and Figure 5

[0112] Referring to FIG. 11C, Figure 11 The communication apparatus 1102 and the communication apparatus 1103 have established a connection through a channel 1 ch (1107) and a channel 48 ch (1110). Furthermore, the communication apparatus 1103 on the channel 1 ch (1107) is in a power save state, and the communication apparatus 1103 on the channel 48 ch (1110) is not in a power save state. The communication apparatus 1102 and the communication apparatus 1104 have established a connection through a channel 1 ch (1108) and a channel 100 ch (1112). Furthermore, the communication apparatus 1104 on the channel 1 ch (1108) and the communication apparatus 1104 on the channel 100 ch (1112) are not in a power save state. The communication apparatus 1102 and the communication apparatus 1105 have established a connection through a channel 1 ch (1109) and a channel 48 ch (1111). Furthermore, the communication apparatus 1105 on the channel 1 ch (1109) and the communication apparatus 1105 on the channel 48 ch (1111) are in a power save state. The communication apparatus 1102 and the communication apparatus 1106 have established a connection through a channel 100 ch (1113). Furthermore, the communication apparatus 1106 on the channel 100 ch (1113) is not in a power save state.

[0113] ​In this way, the communication apparatus 1102 has established links with the communication apparatuses 1103 to 1106 using a plurality of frequency channels, and thus can increase throughput in communication with the communication apparatuses 1103 to 1106. Further, since the communication apparatus 1102 has established a plurality of connections with the communication apparatuses 1103 to 1106 in which the frequency bands are different, the communication apparatus 1102 can communicate with the communication apparatuses 1103 to 1106 through other frequency bands, for example, even in a case where the frequency bands are crowded. Thus, the communication apparatus 1102 can prevent throughput from decreasing in communication with the communication apparatuses 1103 to 1106.

[0114] The STA in the power save state transitions to a state in which communication can be performed by the STA returning from the power save state or by the AP causing the STA to return from the power save state.

[0115] Further, the STA notifies the AP that the STA has returned from the power save state by, for example, transmitting a data frame to the AP in which "0" is stored in a power management subfield of a frame control field of a MAC header. Further, the AP causes the STA to return from the power save state by, for example, transmitting a beacon frame to the STA in which "1" is stored in a bitmap control field of a traffic indication map (TIM) element.

[0116] Figure 12 is a flowchart showing a flow of processing performed by the control unit 402 executing a program stored in the storage unit 401 of the communication apparatus 1102. In the fourth example embodiment, an example is described in which, when the AP blocks or reduces transmission of frames through a frequency channel in which a STA operates in a power save state, the AP determines a frequency channel for transmitting a frame while reducing the number of frequency channels for transmitting frames. Here, the frequency channel in which the STA operates in the power save state refers to a frequency channel through which transmission and reception of frames cannot be performed.

[0117] This flowchart starts by the communication apparatus 1102 transmitting a group addressed frame. Alternatively, this flowchart can start when a connection configuration between the communication apparatus 1102 and another communication apparatus has changed. The connection configuration has changed when, for example, a connection with another communication apparatus has started in a new link, when a connection with another communication apparatus has been cut off, or when a power save state in a frequency channel in a connection process has changed.

[0118] First, in step S1201, the communication apparatus 1102 sets all frequency channels in which the communication apparatus 1102 has established a connection with a STA as a transmission channel candidate group. In the fourth example embodiment, the transmission channel candidate group is set in accordance with the frequency channel configuration example shown in FIG. 10. Figure 11 According to the frequency channel configuration example shown in FIG. 10, the frequency channels 1 ch, 48 ch, and 100 ch are set as the transmission channel candidate group.

[0119] Next, in step S1202, the communication apparatus 1102 sets the number of STAs with which the communication apparatus 1102 has established connection to "x". In the fourth example embodiment, according to the channel configuration example illustrated in FIG. 11, since there are four communication apparatuses 1103 to 1106, "4" is assigned to "x". The communication apparatus 1102 can acquire the number of STAs with which the communication apparatus 1102 has established connection by counting the number of MLDMAC addresses with which it has established connection. Further, the communication apparatus capable of performing multi-link communication stores a multi-link capability element as capability information on multi-link communication in a management frame, and transmits the management frame. The number of STA MAC addresses corresponding to the number of STAs with which it has established connection in each link is included in the STA Info field of the multi-link capability element. Figure 11

[0120] For example, since the communication apparatus 1103 performs communication through two links, two STA MAC addresses are included. Assuming that the case where a plurality of STA MAC addresses are included in the above-described manner indicates the same apparatus, the communication apparatus 1102 can acquire the number of STAs by counting the number of MAC addresses of STAs with which it has established connection in each channel.

[0121] Next, in step S1203, the communication apparatus 1102 assigns "1" to "j", and in step S1204, the communication apparatus 1102 determines whether the total number of STAs in the STAs with which it has established connection that are in the power save state on the channel ch[j] is "x". If it is determined in step S1204 that the total number is "x" (YES in step S1204), the communication apparatus 1102 advances the process to step S1206, and if it is determined that the total number is not "x" (NO in step S1204), the communication apparatus 1102 advances the process to step S1205. Here, ch[j] denotes a channel included in the transmission channel candidate group, and is the jth channel in ascending order of channel number. For example, in the case where the transmission channel candidate group includes channels 1ch, 48ch, and 100ch, ch[1] denotes 1ch, ch[2] denotes 48ch, and ch[3] denotes 100ch. In the fourth example embodiment, since "j" is equal to "1", according to the channel configuration example illustrated in FIG. 11, the number of STAs in the power save state in the channel ch[1] which is the channel 1ch is 2, and thus is not consistent with x=4, so that the communication apparatus 1102 advances the process to step S1205. Figure 11

[0122] ​​Next, in step S1205, the communication apparatus 1102 determines whether "j" is the number of frequency channels included in the transmission channel candidate group. If it is determined that "j" is the number of frequency channels included in the transmission channel candidate group (YES in step S1205), the communication apparatus 1102 advances the process to step S1210. If it is determined that "j" is not the number of frequency channels included in the transmission channel candidate group (NO in step S1205), the communication apparatus 1102 advances the process to step S1209. In the fourth exemplary embodiment, since "j" is equal to "1" and the transmission channel candidate group includes three frequency channels 1ch, 48ch, and 100ch, in step S1209, the communication apparatus 1102 assigns "j+1" to "j".

[0123] When the flow proceeds in this way, even when "j" is equal to "2" or "j" is equal to "3", according to Figure 11 the frequency channel configuration example shown in FIG. 12, the total number of STAs in the power save state is at most 2, and thus is not consistent with x=4, so that the determination result in step S1204 is NO, and the communication apparatus 1102 advances the process to step S1205. Assume that, when "j" is equal to "3", the communication apparatus 1102 has advanced the process to step S1205.

[0124] When "j" is equal to "3", in step S1205, the communication apparatus 1102 determines whether "j" is the number of frequency channels included in the transmission channel candidate group. Since "j" is currently equal to "3" and the number of frequency channels included in the transmission channel candidate group is 3, the communication apparatus 1102 advances the process to step S1210.

[0125] Next, in step S1210, the communication apparatus 1102 determines whether "x" is consistent with "0". If it is determined that "x" is consistent with "0" in step S1210 (YES in step S1210), the communication apparatus 1102 ends the process in this flowchart. The communication apparatus 1102 transmits a frame to the transmission channel candidate group determined at this time. If it is determined that "x" is not consistent with "0" in step S1210 (NO in step S1210), the communication apparatus 1102 advances the process to step S1211. Since "x" is currently equal to "4", it is not consistent with "0", the communication apparatus 1102 advances the process to step S1211, and the communication apparatus 1102 assigns "x-1" to "x". Since "x" is currently 4, the communication apparatus 1102 sets "x=3", and then advances the process to step S1203.

[0126] Next, in step S1203, the communication apparatus 1102 assigns "1" to "j", and then advances the process to step S1204 and subsequent steps again. However, according toFigure 11 The channel configuration example shown is inconsistent with x = 3 because the number of STAs in the power save state is at most 2, so the determination result in step S1204 is "No", as a result, the communication apparatus 1102 advances the process to step S1211.

[0127] Next, in step S1211, the communication apparatus 1102 sets "x = 2", and then in step S1203, the communication apparatus 1102 assigns "1" to "j", and then advances the process to step S1204.

[0128] In step S1204, the communication apparatus 1102 determines whether the total number of STAs in the power save state on the channel ch[j] among the STAs with which a connection is established is "x". In the fourth exemplary embodiment, because "j" is currently equal to "1", the total number of STAs is determined to be "2" in accordance with Figure 11 The channel configuration example shown is inconsistent with x = 3 because the number of STAs in the power save state is at most 2, so the determination result in step S1204 is "No", as a result, the communication apparatus 1102 advances the process to step S1211.

[0129] In step S1206, the communication apparatus 1102 removes the channel ch[j] from the transmission channel candidate group.

[0130] Here, the channel ch[1], that is, the channel 1 ch is removed from the transmission channel candidate group.

[0131] Next, in step S1207, if the frame is transmitted to all channels included in the transmission channel candidate group, the communication apparatus 1102 determines whether the frame has reached all STAs with which a connection is established. Details of the process in step S1207 are described below with reference to Figure 13 Details of the process in step S1207 are described below with reference to

[0132] If it is determined in step S1207 that the frame has reached all STAs (Yes in step S1207), the communication apparatus 1102 advances the process to step S1205, and if it is determined that the frame has not reached all STAs (No in step S1207), the communication apparatus 1102 advances the process to step S1208. According to Figure 11The channel configuration example shown, since the communication apparatus 1102 has removed channel 1 ch from the transmission channel candidate group in step S1206, the transmission channel candidate group consists of channel 48 ch and channel 100 ch. Assuming that transmission to channel 48 ch is performed, frames reach the communication apparatuses 1103 and 1105, and assuming that transmission to channel 100 ch is performed, frames reach the communication apparatuses 1104 and 1106. Therefore, since the frames reach all STAs with which a connection is established in a case where the frames are transmitted to all channels included in the transmission channel candidate group, the communication apparatus 1102 advances the process to step S1205. In this way, the communication apparatus 1102 excludes from the transmission channel candidate group a channel on which the number of STAs in the power save state is the largest and in which, if a frame is transmitted, the frame reaches all STAs. The above-described process makes it possible to prevent or reduce unnecessary frame transmission or unnecessary processing for causing an STA in the power save state to transition to the awake state.

[0133] When the flow proceeds in this way, since the number of STAs in the power save state in channel 48 ch or channel 100 ch does not exceed 1, the determination result in step S1204 becomes "No" in a case where x = 2. Assuming that when "j" is equal to "2", the communication apparatus 1102 has advanced the process to step S1205.

[0134] Since "j = 2" coincides with the number of channels included in the current transmission channel candidate group (48 ch and 100 ch), the communication apparatus 1102 advances the process to step S1210, and in step S1210, the communication apparatus 1102 determines whether "x" coincides with "0". Since the current "x" is equal to "2", the communication apparatus 1102 determines that "x" does not coincide with "0", and then advances the process to step S1211. In step S1211, the communication apparatus 1102 sets "x = 1", and then advances the process to step S1203, and in step S1203, the communication apparatus 1102 sets "j = 1", and then advances the process to step S1204.

[0135] In step S1204, the communication apparatus 1102 determines whether the total number of STAs in the power save state on channel ch[j] among the STAs with which a connection is established is "x". At present, the transmission channel candidate group consists of channel 48 ch and 100 ch, and therefore channel ch[1] is channel 48 ch and channel ch[2] is channel 100 ch. According to the channel configuration example shown, since the number of STAs in the power save state in channel ch[1] (i.e., channel 48 ch) is 1, it coincides with "x = 1", and the communication apparatus 1102 advances the process to step S1206. Figure 11 In step S1206, the communication apparatus 1102 removes channel 1 ch from the transmission channel candidate group. The channel configuration example shown, since the communication apparatus 1102 has removed channel 1 ch from the transmission channel candidate group in step S1206, the transmission channel candidate group consists of channel 48 ch and channel 100 ch. Assuming that transmission to channel 48 ch is performed, frames reach the communication apparatuses 1103 and 1105, and assuming that transmission to channel 100 ch is performed, frames reach the communication apparatuses 1104 and 1106. Therefore, since the frames reach all STAs with which a connection is established in a case where the frames are transmitted to all channels included in the transmission channel candidate group, the communication apparatus 1102 advances the process to step S1205. In this way, the communication apparatus 1102 excludes from the transmission channel candidate group a channel on which the number of STAs in the power save state is the largest and in which, if a frame is transmitted, the frame reaches all STAs. The above-described process makes it possible to prevent or reduce unnecessary frame transmission or unnecessary processing for causing an STA in the power save state to transition to the awake state.

[0136] In step S1206, the communication apparatus 1102 removes the channel ch[j] from the transmission channel candidate group.

[0137] Here, the channel ch[l] (i.e., the channel 48ch) is removed from the transmission channel candidate group.

[0138] Next, in step S1207, if the frame is transmitted to all channels included in the transmission channel candidate group, the communication apparatus 1102 determines whether the frame reaches all STAs with which a connection is established. Details of the processing in step S1207 are described below with reference to Figure 13 The details of the processing in step S1207 are described below with reference to Figure 11 According to the channel configuration example shown in FIG. 10, the transmission channel candidate group consists of only the channel 100ch, and it is assumed that the transmission to the channel 100ch is performed, the frame reaches the communication apparatuses 1104 and 1106. Therefore, since the frame does not reach all STAs with which a connection is established in the case where the frame is transmitted to all channels included in the transmission channel candidate group, the communication apparatus 1102 advances the processing to step S1208.

[0139] Since it is determined in step S1207 that the frame does not reach all STAs, in step S1208, the communication apparatus 1102 adds the channel removed in step S1206 to the transmission channel candidate group. Here, the channel 48ch is added to the transmission channel candidate group, so that the transmission channel candidate group consists of the channels 48ch and 100ch.

[0140] When the flow proceeds in this way, in step S1204, the communication apparatus 1102 extracts the channel in which "x" is equal to "0", i.e., there is no STA in the power save state, and if there is a channel in which there is no STA in the power save state, the communication apparatus 1102 determines whether the frame transmission in the channel can be omitted.

[0141] Next, in step S1210, the communication apparatus 1102 determines whether "x" coincides with "0". Since "x" is equal to "0" at present, it coincides with "0", the communication apparatus 1102 ends the processing in the present flowchart.

[0142] By performing the above-described processing, in the fourth exemplary embodiment, the channels 48ch and 100ch are determined as the transmission channel candidate group, so that the communication apparatus 1102 transmits the frame to the determined channels. Further, since the communication apparatus 1102 does not transmit the frame to the channel which has not been determined, in the fourth exemplary embodiment, the communication apparatus 1102 does not transmit the frame to the channel 1ch.

[0143] Figure 13is a flowchart showing a flow of processing performed by the control unit 402 executing a program stored in the storage unit 401 of the communication apparatus 1102. In the fourth example embodiment, an example is described in which, if a frame is transmitted to the transmission channel candidate group, the AP determines whether the frame reaches all STAs that are connecting to the AP. Figure 13 the flowchart corresponds to Figure 12 the processing in step S1207 shown in Figure 14 the processing in step S1405 shown in.

[0144] When the processing in step S1207 shown in Figure 12 is executed, the present flowchart is started.

[0145] First, in step S1301, the communication apparatus 1102 assigns "1" to "i".

[0146] Next, in step S1302, for the array Dev of elements of which the number is M, the communication apparatus 1102 assigns "0" to the respective elements Dev[1], Dev[2],..., Dev[M]. Here, M is the number of STAs that have established connection with the communication apparatus 1102. According to the channel configuration example shown in Figure 11 , since the communication apparatus 1102 is connecting to the communication apparatuses 1103 to 1106, M is equal to "4". Further, each element Dev[k] is associated with an STA that has established connection. For example, the element Dev[1] is associated with the communication apparatus 1103, the element Dev[2] is associated with the communication apparatus 1104, the element Dev[3] is associated with the communication apparatus 1105, and the element Dev[4] is associated with the communication apparatus 1106. The above association can be performed in such a manner that the elements starting with Dev[1] are associated with the STAs arranged in the alphabetical order of the MAC addresses in the order, are associated with the STAs in the order in which the association is performed, or are associated with the STAs in a random manner without a specific order.

[0147] Next, in step S1303, if a frame is transmitted through the channel ch[i], the communication apparatus 1102 assigns "1" to the element Dev[k] corresponding to all STAs to which the frame reaches. For example, in the case where the transmission channel candidate group is composed of the channels 48ch and 100ch, according to the channel configuration example shown in Figure 11 , the channel ch[1] indicates the channel 48ch. Since the frame transmitted in the channel 48ch reaches the communication apparatus 1103 and the communication apparatus 1105, the communication apparatus 1102 assigns "1" to the associated elements Dev[1] and Dev[3].

[0148] Next, in step S1304, the communication apparatus 1102 determines whether "i" is smaller than the number of frequency channels included in the transmission channel candidate group. If it is determined in step S1304 that "i" is smaller than the number of frequency channels included in the transmission channel candidate group (YES in step S1304), the communication apparatus 1102 advances the process to step S1305. If it is determined in step S1304 that "i" is not smaller than the number of frequency channels included in the transmission channel candidate group (NO in step S1304), the communication apparatus 1102 advances the process to step S1306. In the fourth exemplary embodiment, currently "i" is equal to "1", and in the case where the transmission channel candidate group is composed of the frequency channel 48ch and the frequency channel 100ch, the number of frequency channels is 2, so the communication apparatus 1102 advances the process to step S1305.

[0149] If it is determined in step S1304 that "i" is smaller than the number of frequency channels included in the transmission channel candidate group, in step S1305, the communication apparatus 1102 assigns "i+1" to "i".

[0150] Next, in step S1303, if a frame is transmitted through the frequency channel ch[i], the communication apparatus 1102 assigns "1" to the element Dev[k] corresponding to all STAs to which the frame arrives. For example, in the case where the transmission channel candidate group is composed of the frequency channel 48ch and the frequency channel 100ch, "i" is equal to "2", and according to the frequency channel configuration example shown in FIG. 10, the frequency channel ch[2] indicates the frequency channel 100ch. Since the frame arrives at the communication apparatus 1104 and the communication apparatus 1106 in the case where the frame is transmitted in the frequency channel 100ch, the communication apparatus 1102 assigns "1" to the associated elements Dev[2] and Dev[4]. Figure 11

[0151] Next, in step S1304, the communication apparatus 1102 determines whether "i" is smaller than the number of frequency channels included in the transmission channel candidate group. Since "i" is equal to "2", and in the case where the transmission channel candidate group is composed of the frequency channel 48ch and the frequency channel 100ch, the number of frequency channels is 2 (NO in step S1304), the communication apparatus 1102 advances the process to step S1306.

[0152] ​Next, in step S1306, the communication apparatus 1102 determines whether all elements of the array Dev are "1". If it is determined in step S1306 that at least one element of the array Dev is not "1" ("No" in step S1306), the communication apparatus 1102 advances the process to step S1308. If it is determined in step S1306 that all elements of the array Dev are "1" ("Yes" in step S1306), the communication apparatus 1102 advances the process to step S1307. In the fourth exemplary embodiment, since all elements Dev[1], Dev[2], Dev[3], and Dev[4] are made "1" by the process in step S1303, the communication apparatus 1102 advances the process to step S1307 in which the communication apparatus 1102 determines that the frame reaches all STAs with which a connection is established, and then ends the process in this flowchart.

[0153] On the other hand, in step S1308, if the frame is transmitted to the transmission channel candidate group, the communication apparatus 1102 determines that the frame does not reach all STAs, and then ends the process in this flowchart.

[0154] According to the fourth exemplary embodiment, the communication apparatus 1102 checks whether it is possible to preferentially omit transmission in channels starting from a channel in which the number of STAs in the power save state is the largest. In a case where it is possible to omit transmission in a channel, omission of transmission of a frame in the channel can prevent or reduce unnecessary frame transmission or unnecessary processing to cause an STA in the power save state to transition to the awake state.

[0155] In the fourth exemplary embodiment, an example is described in which, with respect to channels with which the AP and the STA have established a connection, the AP checks whether it is possible to preferentially omit transmission in channels starting from a channel in which the number of STAs in the power save state is the largest. In the fifth exemplary embodiment, an example is described in which, with respect to channels with which the AP and the STA have established a connection, the AP checks all transmission patterns and determines a channel for transmitting a frame while preventing or reducing transmission of a frame to a channel in which an STA operates in the power save state.

[0156] Figure 14 is a flowchart showing a process flow executed by the control unit 402 executing a program stored in the storage unit 401 of the communication apparatus 1102. In the fifth exemplary embodiment, an example is described in which the AP determines a channel for transmitting a frame so as to minimize the number of STAs in the power save state to which the frame is transmitted.

[0157] This flowchart begins with communication device 1102 sending a group addressing frame. Optionally, this flowchart may begin when the connection configuration between communication device 1102 and another communication device has changed. A change in connection configuration means, for example, when a connection with another communication device has begun in a new link, when a connection with another communication device has been terminated, or when the power-saving state of a channel in the process of connection has changed.

[0158] First, in step S1401, the communication device 1102 assigns the number of channels in which the communication device 1102 has established a connection with the STA to "N". According to Figure 11 The channel configuration example shown has three channels: channel 1ch, channel 48ch, and channel 100ch.

[0159] Next, in step S1402, the communication device 1102 exports all transmission modes for all channels with established connections and selects a new mode from the exported channels. Regarding the modes used to transmit frames, the communication device 1102 exports modes whose quantity corresponds to "(2^N) - 1".

[0160] according to Figure 11 The channel configuration example shown assumes seven modes since the established connections are on channels 1ch, 48ch, and 100ch. The first mode is sending frames on channels 1ch, 48ch, and 100ch. The second mode is sending frames on channels 1ch and 48ch but not on channel 100ch. The third mode is sending frames on channel 1ch, not on channel 48ch, and on channel 100ch. The fourth mode is sending frames on channel 1ch, not on channel 48ch, and not on channel 100ch. The fifth mode is not sending frames on channel 1ch, but sending frames on channels 48ch and 100ch. The sixth mode is not sending frames on channel 1ch, but sending frames on channel 48ch and not on channel 100ch. The seventh mode is not sending frames on channels 1ch and 48ch, but sending frames on channel 100ch. Furthermore, regarding the mode of not sending frames in any channel, since it is obvious that the frames do not reach any of the STAS, such a mode need not be considered. In the fifth exemplary embodiment, firstly, it is assumed that the aforementioned first mode has already been selected.

[0161] Next, in step S1403, the communication apparatus 1102 determines whether the mode selected in step S1402 is an unchecked mode. If it is determined that the mode selected in step S1402 is an unchecked mode (YES in step S1403), the communication apparatus 1102 advances the process to step S1404. If it is determined that there is no unchecked mode (NO in step S1403), the communication apparatus 1102 advances the process to step S1407.

[0162] If it is determined in step S1403 that an unchecked mode is selected, in step S1404, the communication apparatus 1102 determines the transmission channel group of the selected mode as a transmission channel candidate group. In the fifth exemplary embodiment, since the first mode is selected first, the transmission channel candidate group is composed of the channels 1ch, 48ch, and 100ch.

[0163] In step S1405, if a frame is transmitted to all channels included in the transmission channel candidate group selected in step S1404, the communication apparatus 1102 determines whether the frame reaches all STAs with which a connection is established. The details of the process in step S1405 are similar to those described with reference to Figure 13 FIG. 14.

[0164] If it is determined in step S1405 that the frame reaches all STAs (YES in step S1405), the communication apparatus 1102 advances the process to step S1406. If it is determined in step S1405 that the frame does not reach all STAs (NO in step S1405), the communication apparatus 1102 advances the process to step S1402. In the fifth exemplary embodiment, since the frame reaches all the communication apparatuses 1103 to 1106 if the frame is transmitted in the channels 1ch, 48ch, and 100ch using the first mode, the communication apparatus 1102 advances the process to step S1406.

[0165] Next, in step S1406, the communication apparatus 1102 stores, in the storage unit 401, the mode selected in step S1402 and the number of STAs in the power save state at that time that serve as transmission destinations. In the case of the first mode, according to Figure 11 the channel configuration example shown in FIG. 14, since the number of STAs in the power save state is 2, the communication apparatus 1102 stores "2" as the number of STAs in the power save state that serve as transmission destinations.

[0166] When the flow proceeds in this way and the number of modes selected in step S1402 is gradually increased, if it is determined in step S1403 that all modes, i.e., the first mode to the seventh mode described above, have been checked, the communication apparatus 1102 advances the process to step S1407.

[0167] In step S1407, the communication apparatus 1102 selects, as a transmission channel group, a mode in which the number of STAs in the power save state as a transmission destination becomes the least, from the modes stored in step S1406. Further, in a case where there are a plurality of modes in which the number of STAs in the power save state as a transmission destination becomes the least in step S1406, the communication apparatus 1102 selects a mode in which the number of channels for transmitting frames is less, as a transmission channel, and then ends the process in this flowchart.

[0168] In the fifth example embodiment, the communication apparatus 1102 prevents or reduces transmission of frames to a channel on which a STA operates in the power save state, and determines a channel for transmitting frames while reducing the number of channels for transmitting frames. Performing the above-described process can prevent or reduce unnecessary frame transmission or is unnecessary processing for causing a STA in the power save state to transition to the awake state.

[0169] Further, although in the fifth example embodiment, an example is described in which the AP prevents or reduces transmission of frames to a channel on which a STA operates in the power save state, and determines a channel for transmitting frames while reducing the number of channels for transmitting frames, the fifth example embodiment is not limited thereto. The fifth example embodiment can also be applied to a case where the AP prevents or reduces transmission of frames to a channel in which the degree of congestion is high, as in the second example embodiment.

[0170] Although in the above-described example embodiments, an example is described in which the AP has Figure 4 The communication apparatus having the hardware configuration illustrated in Figures 7 to 10 and Figures 12 to 14 the flowchart illustrated in Figure 4 The wireless chip including the storage unit, the control unit, and the communication unit illustrated in Figure 4 may also be configured to perform the process in the above-described flowchart. Thus, the communication apparatus according to each example embodiment can be a wireless chip including the storage unit, the control unit, and the communication unit illustrated in

[0171] Further, a configuration can be employed in which a storage medium storing program code of software for implementing the above-described functions is provided to a system or an apparatus, and a computer (central processing unit (CPU) or micro processing unit (MPU)) of the system or the apparatus reads out and executes the program code stored in the storage medium. In this case, the program code read out from the storage medium realizes the functions of the above-described example embodiments, and the storage medium storing the program code configures the above-described apparatus.

[0172] The storage medium for providing the program code includes, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a non-volatile memory card, a ROM, and a digital versatile disk (DVD).

[0173] Further, not only a configuration in which the program code read out by the computer is executed to realize the above-described functions is employed, but also an operating system running on the computer can perform part or all of the actual processing operations based on the instructions of the program code to realize the above-described functions. OS is an abbreviation for operating system.

[0174] Further, the program code read out from the storage medium can be written into a memory included in a function expansion card inserted into the computer or a function expansion unit connected to the computer.

[0175] Then, the CPU included in the function expansion card or the function expansion unit can perform part or all of the actual processing operations based on the instructions of the program code to realize the above-described functions.

[0176] Each of the example embodiments of the present application can also be realized by a circuit (for example, an application specific integrated circuit (ASIC)) that realizes one or more functions of the above-described example embodiments, by executing a process for providing a program for realizing one or more functions of the above-described example embodiments to a system or an apparatus through a network or a storage medium, and causing one or more processors included in a computer of the system or the apparatus to read out and execute the program.

[0177] According to each of the example embodiments of the present application, when a communication apparatus and other communication apparatuses have established connections through a plurality of frequency channels, frame transmission through all of the frequency channels through which the connections have been established can be prevented or reduced.

[0178] Other Embodiments

[0179] The various embodiments of the present application can also be implemented by a method of providing software (program) for performing the functions of the above-described embodiments to a system or an apparatus through a network or various storage media, and a method of reading and executing the program by a computer or a central processing unit (CPU) micro processing unit (MPU) of the system or the apparatus.

[0180] While exemplary embodiments of the present application have been described, it is to be understood that the application is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A communication apparatus comprising: a communication unit configured to communicate an association frame with another communication apparatus, the association frame being used to establish a first link through a first frequency channel, a second link through a second frequency channel, and a third link through a third frequency channel; and a transmission unit configured to transmit a frame through a multicast communication or a broadcast communication, wherein, in a case where the first link and the second link are a pair of non-simultaneous transmission and reception (non-STR) links, the frame is transmitted through the third link, and the frame is not transmitted through the first link or the second link.

2. The communication apparatus according to claim 1, wherein The frame is a group addressed frame.

3. The communication apparatus according to claim 1, wherein The communication apparatus performs communication compliant with IEEE 802.11 series standards.

4. The communication apparatus according to claim 1, wherein For the first link and the second link being a pair of non-STR links, data cannot be received through the first link while data is transmitted through the second link.

5. The communication apparatus according to claim 1, wherein The third link has a simultaneous transmission and reception (STR) relationship with the first link and the second link.

6. The communication apparatus according to claim 2, wherein The group addressed frame is a management frame. 7.A communication method for a communication apparatus, the communication method comprising: communicating an association frame with another communication apparatus, the association frame being used to establish a first link through a first frequency channel, a second link through a second frequency channel, and a third link through a third frequency channel; and transmitting a frame through a multicast communication or a broadcast communication, wherein, in a case where the first link and the second link are a pair of non-simultaneous transmission and reception (non-STR) links, the frame is transmitted through the third link, and the frame is not transmitted through the first link or the second link. 8.A non-transitory computer-readable storage medium storing computer-executable instructions that, when executed by a computer, cause the computer to perform a method for a communication apparatus, the method comprising: communicating an association frame with another communication apparatus, the association frame being used to establish a first link through a first frequency channel, a second link through a second frequency channel, and a third link through a third frequency channel; and transmitting a frame through a multicast communication or a broadcast communication, wherein, in a case where the first link and the second link are a pair of non-simultaneous transmission and reception (non-STR) links, the frame is transmitted through the third link, and the frame is not transmitted through the first link or the second link.

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