Communication device, communication method, and storage medium

Abstract

The present invention provides a communication device, a communication method, and a storage medium. A communication device includes: a establishing unit configured to establish a first connection between the communication device and a first other communication device via one or more links using one or more frequency channels, and establish a second connection between the communication device and a second other communication device via one or more links using one or more frequency channels; a determining unit configured to determine a frequency channel required for a frame transmitted in multicast communication or broadcast communication to reach the first other communication device and the second other communication device, wherein the frequency channel is determined among a plurality of frequency channels used in the links of the first and second connections established by the establishing unit; and a transmitting unit configured to transmit a frame on the frequency channel determined by the determining unit.

Description

Technical Field

[0001] The present invention relates to a communication device for wireless communication. Background Art

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

[0003] The technology discussed in Japanese Unexamined Patent Application Publication No. 2018-50133 achieves an increase in communication speed in a congested situation in addition to achieving a peak throughput of up to 9.6 gigabits per second (Gbps) by using orthogonal frequency division multiple access (OFDMA) defined in IEEE 802.11ax.

[0004] In order to further increase the throughput, a task group has been launched to design the standard IEEE 802.11be as a subsequent standard to the IEEE 802.11ax standard.

[0005] In connection with the IEEE 802.11be standard, a communication technology has been studied in which an access point (AP) establishes multiple links with a station (STA) via multiple different frequency channels.

[0006] In the IEEE 802.11be standard, using the above-mentioned multiple frequency channels, it has been discussed that the AP and the STA establish a connection via multiple channels and perform multi-link communication in parallel therebetween.

[0007] In a case where the AP has established a connection with the STA via multiple frequency channels and the AP sends a frame via multicast communication or broadcast communication, the same frame may be sent to the same STA multiple times. Therefore, via the multi-link connection between the AP and the STA, the frame is redundantly sent to a frequency channel that does not need to receive the frame, that is, the AP sends an unnecessary frame. Summary of the Invention

[0008] Various embodiments of the present invention provide techniques and mechanisms for preventing the transmission of unnecessary frames to a frequency channel that does not need to receive the frames when a communication device is connected to multiple communication devices and the communication device is connected to at least one of the multiple communication devices via multiple frequency channels.

[0009] According to one embodiment, a communication device provided includes: a establishing unit configured to establish a first connection between the communication device and a first other communication device via one or more links using one or more frequency channels, and establish a second connection between the communication device and a second other communication device via one or more links using one or more frequency channels; a determining unit of the communication device further configured to determine a frequency channel required for a frame transmitted in multicast communication or broadcast communication to reach the first other communication device and the second other communication device. The frequency channel is determined from among a plurality of frequency channels used in the links of the first and second connections established by the establishing unit. In addition, the communication device includes a transmitting unit configured to transmit a frame on the frequency channel determined by the determining unit.

[0010] Additional features of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a diagram showing the configuration of a network established by a communication device according to one embodiment.

[0012] Figure 2 is a diagram showing an example of the frequency channel configuration of a network established by a communication device according to one embodiment.

[0013] Figure 3 is a diagram showing the hardware configuration of a communication device according to one embodiment.

[0014] Figure 4 is a diagram showing the functional configuration of a communication device according to one embodiment.

[0015] Figure 5 is a sequence diagram showing an example of processing to be performed in the case of multi-link communication between a communication device and another communication device according to one embodiment.

[0016] Figure 6 is a flowchart for determining a transmission frequency channel group for transmitting a frame according to one embodiment.

[0017] Figure 7 is a flowchart showing the completion of determination of a transmission frequency channel group for transmitting a frame according to one embodiment. DETAILED DESCRIPTION

[0018] Exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The configurations to be described in the following exemplary embodiments are merely examples, and the present invention is not limited to the shown configurations.

[0019] Next, a first exemplary embodiment will be described. Figure 1Shows the configuration of a network established by communication device 102 according to this exemplary embodiment. Communication device 102 is an access point (AP) that functions in establishing network 101. Network 101 is a wireless network.

[0020] Each of communication devices 103 to 106 is a station (STA) that functions in participating in network 101. Each of communication devices 102 to 106 supports the Institute of Electrical and Electronics Engineers (IEEE) 802.11be (Extremely High Throughput (EHT)) standard and can perform wireless communication compliant with the IEEE 802.11be standard via network 101. Each of communication devices 102 to 106 can communicate at frequency bands in the 2.4 GHz, 5 GHz, and 6 GHz bands. The frequency bands used by each of communication devices 102 to 106 are not limited to these bands. For example, different frequency bands such as the 60 GHz band can be used. Each of communication devices 102 to 106 can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz.

[0021] Communication devices 102 to 106 can achieve multi-user (MU) communication of multiplexed signals of multiple users by performing orthogonal frequency division multiple access (OFDMA) communication compliant with the IEEE 802.11be standard. In OFDMA communication, a part of the divided frequency band (resource unit (RU)) is allocated to each STA without overlapping with each other, and the carriers allocated to each STA are orthogonal to each other. Therefore, the AP can communicate with multiple STAs in parallel. Arrows 113 to 116 indicate that communication device 102 has one or more wireless connection links to each of communication devices 103 to 106.

[0022] Figure 2 Shows an example of the frequency channel configuration of the network established by communication device 102. Communication devices 102 to 106 establish links via multiple frequency channels to perform multi-link communication. Here, the frequency channel is a frequency channel defined in the IEEE 802.11 standard series and refers to a frequency channel on which wireless communication compliant with the IEEE 802.11 standard series can be performed. In the IEEE 802.11 standard series, multiple frequency channels are defined in each of the 2.4 GHz, 5 GHz, and 6 GHz bands. In addition, in the IEEE 802.11 standard series, the bandwidth of each frequency channel is defined as 20 MHz. Adjacent channels are bound together to form a bandwidth of greater than or equal to 40 MHz, and a bandwidth of greater than or equal to 40 MHz can be used for one frequency channel.

[0023] The communication device 102 and the communication device 103 are connected via the frequency channel 1ch indicated by the arrow 201 and the frequency channel 48ch indicated by the arrow 204. The communication device 102 and the communication device 104 are connected via the frequency channel 1ch indicated by the arrow 202 and the frequency channel 36ch indicated by the arrow 203. The communication device 102 and the communication device 105 are connected via the frequency channel 48ch indicated by the arrow 205 and the frequency channel 100ch indicated by the arrow 206. The communication device 102 and the communication device 106 are connected via the frequency channel 100ch indicated by the arrow 207. In this way, by establishing links with the communication devices 103 to 106 via multiple frequency channels, the communication device 102 can improve the throughput of communication with the communication devices 103 to 106. Since the communication device 102 has established multiple connections with different frequency channels to the communication devices 103 to 106, even when the predetermined frequency band is congested, the communication device 102 can use other frequency bands to communicate with the communication devices 103 to 106. Therefore, a decrease in the throughput of communication with the communication devices 103 to 106 can be prevented.

[0024] In multi-link communication, the multiple links established between the communication device 102 and each of the communication devices 103 to 106 can be different at least in terms of frequency channels. In multi-link communication, the channel interval between the frequency channels of the multiple links established between the communication device 102 and each of the communication devices 103 to 106 can be at least greater than 20 MHz.

[0025] In the case of performing multi-link communication, the communication device 102 separates one piece of data and sends each separated piece of data to the partner device via multiple links. Alternatively, the communication device 102 can send the same data via multiple links established with any of the communication devices 103 to 106, so that the communication via one of these links can be used as backup communication for the communication via other links.

[0026] Specifically, the communication device 102 transmits the same data to the communication device 104 via a first link using channel 1ch and a second link using channel 36ch. In this case, even if an error occurs, for example, during communication via the first link (channel 1ch), the communication device 104 can receive the data transmitted from the communication device 102 via the second link (channel 36ch). Alternatively, the communication device 102 can selectively use the links according to the type of frame to be transmitted and the type of data. For example, the communication device 102 can transmit management frames via the first link (channel 1ch) and can transmit data frames including data via the second link (channel 36ch). Management frames specifically refer to beacon frames, probe request frames / probe response frames, and association request frames / association response frames. In addition to these frames, disassociation frames, authentication frames, deauthentication frames, and action frames are also referred to as management frames. A beacon frame is a frame that announces network information. A probe request frame is a frame that requests network information, and a probe response frame is a response to the probe request frame and is a frame that provides network information. An association request frame is a frame that requests a connection, and an association response frame is a response to the association request frame and is a frame that indicates whether a connection is allowed or an error in the connection. A disassociation frame is a frame that terminates a connection. An authentication frame is a frame that authenticates a partner device, and a deauthentication frame is a frame that stops authenticating a partner device and terminates the connection. An action frame is a frame used to perform other functions other than the above functions. Each of the communication devices 102 to 106 transmits and receives management frames compliant with the IEEE 802.11 standard series. Alternatively, for example, when the communication device 102 transmits data regarding a captured image, the communication device 102 can transmit meta-information such as a date, parameters (aperture value and shutter speed) at the time of capturing the image, and location information via the first link, and can transmit pixel information via the second link.

[0027] The communication devices 102 to 106 can perform multiple-input and multiple-output (MIMO) communication. In this case, each of the communication devices 102 to 106 has multiple antennas, and the communication device 102 or any one of the communication devices 102 to 106 transmits different signals through their respective antennas using the same frequency channel. The receiver uses multiple antennas to simultaneously receive all signals from multiple streams, separates the signals of each stream, and decodes the separated signals. By performing MIMO communication in this way, the communication devices 102 to 106 can communicate more data within the same time period compared to the case where MIMO communication is not performed. In addition, in the case of multi-link communication, the communication devices 102 to 106 can perform MIMO communication in some of the links.

[0028] In this exemplary embodiment, the communication devices 102 to 106 support the IEEE 802.11be standard. However, in addition to or instead of IEEE 802.11be, they may also support at least one of the legacy standards that are standards prior to the IEEE 802.11be standard. The legacy standards are the IEEE 802.11a / b / g / n / ac / ax standards. In this exemplary embodiment, at least one of the IEEE 802.11a / b / g / n / ac / ax / be standards and their subsequent standards will be referred to as the IEEE 802.11 standard series. In addition to supporting the IEEE 802.11 standard series, the communication devices 102 to 106 may also support other communication standards such as Near Field Communication (NFC), Ultra-Wideband (UWB), Multi-Band Orthogonal Frequency Division Multiplexing Alliance (MBOA). UWB includes, for example, Wireless Universal Serial Bus (USB), Wireless 1394, and Winet. In addition, the communication devices 102 to 106 may support communication standards for wired communication such as wired Local Area Network (LAN).

[0029] Specific examples of the communication device 102 include a Wireless LAN router and a Personal Computer (PC), but the communication device 102 is not limited to these examples. The communication device 102 can be any type of communication device as long as the device can perform multi-link communication with other communication devices. Specific examples of the communication devices 103 to 106 include a camera, a tablet computer, a smart phone, a PC, a mobile phone, and a video camera, but the communication devices 103 to 106 are not limited to these examples. Each of the communication devices 103 to 106 can be any type of communication device as long as the device can perform wireless link communication with other communication devices. Figure 1 and Figure 2 The network 101 shown includes one AP and four STAs, but the number of APs and the number of STAs are not limited to this.

[0030] Figure 3 Shows the hardware configuration of the communication device 102 in this exemplary embodiment. The communication device 102 has a storage unit 301, a control unit 302, a functional unit 303, an input unit 304, an output unit 305, a communication unit 306, and an antenna 307.

[0031] The storage unit 301 includes at least one memory such as a read-only memory (ROM) or a random access memory (RAM), and stores a computer program for performing various operations to be described below, as well as various information such as communication parameters for wireless communication. In addition to memories such as ROM or RAM, storage media such as floppy disks, hard disks, optical disks, magneto-optical disks, compact disk ROMs (CD-ROMs), recordable CDs (CD-Rs), magnetic tapes, non-volatile memory cards, or digital versatile disks (DVDs) can be used as the storage unit 201. The storage unit 301 may include a plurality of memories.

[0032] The control unit 302 includes at least one processor such as a central processing unit (CPU) or a microprocessing unit (MPU), and controls the entire communication device 102 by executing the computer program stored in the storage unit 301. The control unit 302 can control the entire communication device 102 based on the cooperation between the computer program stored in the storage unit 301 and an operating system (OS). In addition, the control unit 302 generates data and signals (wireless frames) to be transmitted in communication with other communication devices. The control unit 302 may include a plurality of processors such as a multi-core processor, and can control the entire communication device 102 by using the plurality of processors.

[0033] In addition, the control unit 302 also performs predetermined processing such as wireless communication, image capture, printing, and projection by controlling the functional unit 303. The functional unit 303 is hardware for the communication device 102 to perform predetermined processing.

[0034] The input unit 304 receives various operations from the user. The output unit 305 provides various outputs to the user via a monitor screen and a speaker. Here, the output from the output unit 305 can be displayed on the monitor screen, can be sound output from the speaker, and vibration output. The input unit 304 and the output unit 305 can be implemented as one module such as a touch panel. The input unit 304 and the output unit 305 can be integrated with the communication device 102 or independent of the communication device 102.

[0035] The communication unit 306 controls wireless communication compliant with the IEEE 802.11be standard. In addition to the IEEE 802.11be standard, the communication unit 306 can also control wireless communication compliant with other standards of the IEEE 802.11 standard series, and can control wired communication using a wired LAN or the like. The communication unit 306 controls the antenna 307 to transmit and receive signals for wireless communication generated by the control unit 302. In the communication device 102, in addition to the IEEE 802.11be standard, it also supports standards such as the NFC standard and In the case of other standards of the standard, the communication device 102 can control wireless communication conforming to these communication standards. When the communication device 102 can perform wireless communication conforming to multiple communication standards, the communication device 102 can be configured to include a communication unit and an antenna for each communication standard. The communication device 102 communicates data such as image data, document data, and video data with the communication device 103 via the communication unit 306. The antenna 307 can be configured independently of the communication unit 306, or can be configured integrally with the communication unit 306 to form a module.

[0036] The antenna 307 can communicate in the 2.4 GHz, 5 GHz, and 6 GHz frequency bands. In the present exemplary embodiment, the communication device 102 includes one antenna, but may have different antennas for each frequency band. When the communication device 102 includes multiple antennas, the communication device 102 can have a communication unit 306 for each antenna.

[0037] Each of the communication devices 103 to 106 has a hardware configuration similar to that of the communication device 102.

[0038] Figure 4 The functional configuration of the communication device 102 according to the present exemplary embodiment is shown. The communication device 102 includes: a capability information generation unit 401 for multi-link communication, an operation information determination unit 402 for multi-link communication, a group addressing frame transmission frequency channel determination unit 403, a connection processing unit 404, and a data transmission / reception unit 406.

[0039] The capability information generation unit 401 is a block that generates capability information regarding multi-link communication performed by the communication device 102. The communication device 102 generates capability information to notify other communication devices of its own capabilities regarding multi-link communication. Here, the capability information refers to the frequency bands, frequency channels, and bandwidths that the communication device 102 can use. The communication device 102 can notify its own capability information to other communication devices, or can only receive the capability information regarding the partner device from other communication devices.

[0040] The operation information determination unit 402 is a block that determines operation information regarding multi-link communication with the partner device based on the capability information related to multi-link communication of its own device and the partner device. The operation information related to multi-link communication refers to the frequency channels, bandwidths, etc. used in the multi-link communication between the communication device 102 and each of the communication devices 103 to 106. The determined operation information may or may not be notified to the partner device.

[0041] The group addressing frame transmission frequency channel determination unit 403 is a block that determines a target frequency channel group to be used for the transmission of group addressing frames. The frequency channels of the target frequency channel group to be used for transmitting group addressing frames are determined based on information about the connection of frequency channels obtained from the capability information generation unit 401 or the connection processing unit 404. Here, a group addressing frame refers to a frame in which the group bit in the media access control (MAC) address to be included in the destination address (DA) of the MAC frame is set to 1. For example, since the group bit is set to 1, a frame transmitted in broadcast communication such as a beacon frame is a type of group addressing frame. Similarly, since the group bit is set to 1, a multicast frame is also a group addressing frame. Group addressing frames are transmitted in multicast communication or broadcast communication.

[0042] The connection processing unit 404 is a block that performs processing for enabling communication devices 103 to 106 acting as STAs to join a network established by the communication device 102. Specifically, for example, the connection processing section 404 causes the communication device 102 to transmit an association response frame as a response to an association request, which is a connection request received from the communication device 103. The communication device 102 may have a connection processing unit 404 for each of the multiple links established by the communication device 102, or may use one connection processing unit 404 in a time-sharing manner.

[0043] The data transmission / reception unit 406 is a block that transmits and receives data frames in multi-link communication based on operation information related to multi-link communication determined by the operation information determination unit 402.

[0044] Each of the communication devices 103 to 106 has a functional structure similar to that of the communication device 102, but there are the following differences.

[0045] Each of the communication devices 103 to 106 includes a request information determination unit (not shown) that replaces the operation information determination unit 402. The request information determination unit is a block that determines request information related to multi-link communication established with a partner device based on capability information related to multi-link communication of its own device and the partner device. Request information related to multi-link communication refers to frequency channels, bandwidths, etc. requested to be used in multi-link communication between the communication device 102 and each of the communication devices 103 to 106. The determined request information may or may not be notified to the partner device.

[0046] Figure 5 It is a sequence diagram showing an example of the processing to be executed when the communication device 102 and the communication device 103 perform multi-link communication.

[0047] An example will be described in which the communication device 102 and the communication device 103 communicate via the first link using channel 1ch in the 2.4 GHz band and perform processing for communication via the second link using channel 36ch in the 5 GHz band.

[0048] When both the communication devices 102 and 103 are powered on, Figure 5 the processing in the shown sequence starts. Alternatively, at least one of the communication devices 102 and 103 may start the processing in response to an instruction from a user or an application to start multi-link communication. Or, at least one of the communication devices 102 and 103 may start the processing when the amount of data to be communicated with a partner device reaches or exceeds a predetermined threshold.

[0049] First, in step S501, the communication device 102 sends a beacon including network information about the communication device 102 using channel 1ch, thereby notifying nearby STAs of the network information. Specifically, the network information is the transmission interval at which the communication device 102 sends the beacon, and the service set identifier (SSID) of the communication device 102. Additionally, the communication device 102 may include the network information in the beacon, thereby advertising the capability information related to multi-link communication of the communication device 102.

[0050] In step S502, when receiving the beacon sent from the communication device 102 via channel 1ch, the communication device 103 sends a probe request via channel 1ch. The probe request includes the SSID of the communication device 103. Additionally, the communication device 103 advertises the capability information related to multi-link communication of the communication device 103.

[0051] In step S503, when receiving the probe request, the communication device 102 sends a probe response to the communication device 103 via channel 1ch. In the case where the capability information related to multi-link communication is not included in the beacon, the communication device 102 sends a probe response including the capability information. Alternatively, the communication device 102 may include only a part of the capability information related to multi-link communication in the beacon and include the remaining information or all the information in the probe response.

[0052] The communication devices 102 and 103 can exchange the capability information related to multi-link communication with each other by performing the processing in steps S501 to S503.

[0053] Next, in step S504, the communication device 103 sends an association request as a connection request to the communication device 102 via channel 1ch. In this case, the communication device 103 may advertise the capability information related to multi-link communication of the communication device 103 by including the capability information related to multi-link communication of the communication device 103 in the association request.

[0054] The communication device 103 may determine the capability information to be transmitted in step S504 based on the multi-link communication-related capability information of the communication device 102 obtained in at least one of step S501 and step S503. For example, assume that the communication device 103 can combine a link in the 2.4 GHz band and a link in the 5 GHz band in multi-link communication, but the communication device 102 only supports multiple links within the 2.4 GHz band. In this case, the communication device 103 may transmit only the capability information of the communication device 103 for establishing multiple links in the 2.4 GHz band as the capability information transmitted in this step. In the present exemplary embodiment, the case where the communication device 103 transmits the multi-link communication-related capability information of the communication device 103 in step S502 has been described. However, this configuration is not limited thereto, and the communication device 103 may transmit the capability information only in step S504 and not in step S502. Alternatively, the communication device 103 may transmit request information for requesting multi-link communication by including the multi-link communication-related capability information in the association request instead of the capability information. The request information requested by the communication device 103 may be indicated by the multi-link communication-related capability information or may be indicated by other elements.

[0055] In step S505, when receiving the association request, the communication device 102 transmits an association response to the communication device 103 via channel 1ch. The association response transmitted in this step includes the operation information determined by the communication device 102 for multi-link communication with the communication device 103. In addition, in the case where the association request including the requested operation information is transmitted by the communication device 103 acting as the STA in step S504, the communication device 102 may transmit an association response including only the approval or rejection of the request.

[0056] In the case where the communication device 103 can perform multi-link communication based on the operation information included in the association response, in step S506, the communication devices 102 and 103 establish a link via channel 1ch and start data communication. In addition, in the case where the operation information regarding the link via channel 36ch is included in the operation information transmitted by the communication device 102, in step S507, the communication devices 102 and 103 also establish a link via channel 36ch and start data communication.

[0057] For the request information requested by the communication device 103 in step S504, in the case where the communication device 102 sends a response indicating approval in step S505, the processing in step S506 is similarly performed. In the case where the request information sent by the communication device 103 in step S504 further includes request information regarding the link via the channel 36ch, the processing in step S507 is performed.

[0058] In the present exemplary embodiment, two links are established by transmitting and receiving frames using one frequency channel. However, the number of links to be established is not limited thereto, and three or more links may be established.

[0059] In the present exemplary embodiment, the case where multi-link communication is started in a state where no link has been established between the communication device 102 and the communication device 103 is described, but the configuration is not limited thereto.

[0060] The communication devices 102 and 103 may start multi-link communication by establishing a new link in addition to the already established link. In this case, if the capability information related to multi-link communication of the communication device 102 acting as an AP has been acquired, the communication device 103 acting as an STA may start from step S504. Alternatively, in the case where the capability information related to multi-link communication of the communication device 103 has been acquired, the communication device 102 may send a signal for causing the communication device 103 to send an association request, and thus the processing may start from step S504. Alternatively, the communication devices 102 and 103 may establish a new link in addition to the multiple already established links. In these cases, Figure 5 the processing in the sequence may start from step S504.

[0061] In the present exemplary embodiment, the case where links are established via multiple frequency channels by transmitting and receiving frames via one frequency channel has been described, but the configuration is not limited thereto. In the case of performing multi-link communication, the communication devices 102 and 103 may disconnect the links that have been established between them via multiple frequency channels by transmitting and receiving frames via one frequency channel.

[0062] As Figure 5 shown, by transmitting and receiving frames via a certain frequency channel (or link), the communication devices 102 and 103 can control the establishment and disconnection of the links via other frequency channels. In addition, by transmitting and receiving frames via a certain frequency channel (or link), the communication devices 102 and 103 can control the establishment and disconnection of the links via multiple frequency channels.

[0063] Similarly, each of communication devices 102 and 104 to 106 can also control the establishment and disconnection of links in other frequency channels by sending and receiving frames via a certain frequency channel (or link).

[0064] In addition, in Figure 5 the sequence of, the sender can include its own Multi-Link Device (MLD) MAC address in at least one management frame sent in the above steps S501 to S505. The MLD MAC address is identification information regarding a communication device that can perform multi-link communication.

[0065] In addition, the sender can include its own MLD MAC address in at least one of the frames other than the management frames sent in steps S501 to S505.

[0066] Figure 6 is a flowchart showing the flow of processing performed when the control unit 302 executes a program stored in the storage unit 301 of the communication device 102. In the present exemplary embodiment, the following example will be described: When the determination of the frequency channel has not been completed, the frequency channel through which the frame is to be sent is determined.

[0067] The processing in this flowchart starts when the communication device 102 sends a group addressing frame. Alternatively, when the connection configuration of the communication device 102 to other communication devices changes, the communication device 102 can start the processing in this flowchart. The case where the connection configuration changes means, for example, the case where the communication device 102 starts connecting to other communication devices using a new link, or the case where the connection to other communication devices is terminated.

[0068] First, in step S601, the communication device 102 determines, in the frequency channel connected to the STA, the frequency channel in which a connection has been established with the STA that does not act as an MLD as the frequency channel through which the frame is to be sent. In other words, the communication device 102 adds this frequency channel to the transmission frequency channel group. Here, an MLD is a communication device that can perform communication with a partner device in parallel via multiple frequency channels. In the present exemplary embodiment, since the communication devices 103 to 106 are all MLDs, no frequency channel is added to the transmission frequency channel group here.

[0069] In step S602, the communication device 102 identifies the STAs connected to the communication device 102 using a single frequency channel, and determines this frequency channel as the frequency channel through which the frame is to be transmitted. In other words, the communication device 102 adds this frequency channel to the transmission frequency channel group. A method for identifying the STAs that have established a connection with the communication device 102 using a single frequency channel will be described below. When the communication device 102 has established a connection with each of the communication devices 103 to 106 via the respective frequency channels, the communication device 102 has obtained the respective MLD MAC addresses of the communication devices 103 to 106.

[0070] Referring to Figure 2 the structural example shown, for example, the communication device 103 has established a connection with the communication device 102 via channels 1ch and 48ch, so the communication device 102 has obtained two MLD MAC addresses from the communication device 103. Therefore, the communication device 103 is not an STA that has established a connection with the communication device 102 via a single frequency channel. At the same time, for example, the communication device 106 has established a connection with the communication device 102 only via channel 100ch, so the communication device 102 has obtained one MLD MAC address of the communication device 106.

[0071] In the present exemplary embodiment, the MLD MAC address or multiple MLD MAC addresses obtained at the time of connection establishment are used as described above, but the structure is not limited thereto. The MLD MAC addresses obtained at different timings can be used to search for the corresponding MLDs. For example, in step S602, the communication device 102 can ask the communication devices to be connected via the respective frequency channels about the MLD MAC addresses of the communication devices to be connected.

[0072] In Figure 2 the structural example shown, the communication device 102 and the communication device 105 have established a connection via channels 48ch and 100ch, and the communication device 102 and the communication device 106 have established a connection via channel 100ch. In Figure 2 this case, since the connection between the communication device 102 and the communication device 105 and the connection between the communication device 102 and the communication device 106 have been established via the shared channel 100ch, the frame is transmitted via channel 100ch.

[0073] A case will be described in which the communication device 102 and the communication device 105 establish a connection via a single frequency channel, the communication device 102 and the communication device 106 establish a connection via two different frequency channels, and these three frequency channels are different from each other. In the case where the above three frequency channels are different from each other, a frame is sent to a single frequency channel. In this way, by determining the frequency channel for sending the frame, the number of frequency channels for sending the frame can be restricted, and the frame can also be reliably sent to the STA that has established a connection via a single frequency channel.

[0074] In step S603, the communication device 102 determines whether the determination of the transmission frequency channel group is completed. The determination method will be described below with reference to Figure 7 and thus the description thereof will be omitted here. If the determination is completed (Yes in step S603), the process of determining the transmission frequency channel group ends.

[0075] If the determination of the transmission frequency channel group is not completed (No in step S603), the process proceeds to step S604. In step S604, the communication device 102 acquires the STAs that do not receive the frames even if the frames are sent in the frequency channels determined in step S601 or step S602. Referring to the Figure 2 construction example shown, since it is determined in step S602 that these frames are sent via channel 100ch, these frames are sent to each of the communication devices 105 and 106. However, these frames are not sent to any of the communication devices 103 and 104, so that the STAs acquired in step S604 are the communication devices 103 and 104.

[0076] In step S605, the communication device 102 adds the frequency channel that can send frames to the largest number of STAs among the STAs acquired in step S604 to the transmission frequency channel group. In other words, in the case where there is the same frequency channel among the frequency channels via which the communication device 102 is connected to the STAs acquired in step S604, the frames are sent via this frequency channel. Referring to the Figure 2 construction example shown, each of the communication devices 103 and 104 has established a connection with the communication device 102 via channel 1ch, so that frames can be sent to the largest number of communication devices (STAs) via channel 1ch. Therefore, channel 1ch is added to the transmission frequency channel group. In other words, since the connection between the communication device 102 and the communication device 104 and the connection between the communication device 102 and the communication device 103 are both established via channel 1ch which is the same frequency channel, the frames are sent via channel 1ch.

[0077] In step S605, the frequency channel through which the frame is to be transmitted is determined. In other words, in step S605, the frequency channel through which the frame is to be transmitted is added to the transmission frequency channel group. After the frequency channel is added to the transmission frequency channel group, the process returns to step S603, and the communication device 102 determines whether the determination of the frequency channel for transmitting the frame is completed. In the present exemplary embodiment, referring to Figure 2 the structural example shown, if the transmission frequency channel group of channel 1ch and 100ch is used to transmit the frame, the frame can be transmitted to the communication devices 103 to 106, and thus, the process of determining the transmission frequency channel group ends.

[0078] In the case where there are two or more frequency channels through which the frame can be transmitted to the maximum number of STAs, one frequency channel can be randomly selected therefrom, one frequency channel can be selected based on the order of the number of channels of the frequency channels, or one frequency channel can be selected by different determination methods. As different determination methods, there is a method that determines the frequency channel while avoiding the frequency channels with severe congestion, the frequency channels used by the STAs operating in the power saving state, and the frequency channels operating in non-simultaneous transmit and receive (non-STR).

[0079] Figure 7 is a flowchart showing the processing flow when the program stored in the storage unit 301 of the communication device 102 is executed by the control unit 302. In this flowchart, the communication device 102 determines whether the determination of the frequency channel group for transmitting the group addressed frame is completed when transmitting the group addressed frame to the communication devices 103 to 106.

[0080] In step S701, the communication device 102 acquires a first MAC address group, which is a group of MAC addresses of STAs, and each STA has established a connection via the frequency channel determined to be used for transmitting the frame. In the present exemplary embodiment, the MLD MAC address is used as the MAC address of the STA.

[0081] In step S702, the communication device 102 acquires a second MAC address group, which is a group of MAC addresses of all STAs that have established connections via all frequency channels. For the first MAC address group and the second MAC address group, the first MAC address group can be acquired in advance instead of when the determination of the frequency channel group for transmitting the frame is completed. For example, the first MAC address group can be acquired when the connection with the STA is established or terminated.

[0082] In step S703, the communication device 102 determines whether the first MAC address group and the second MAC address group are identical to each other. If the communication device 102 determines that the first MAC address group and the second MAC address group are identical to each other (Yes in step S703), the process proceeds to step S704. In step S704, the communication device 102 determines that the determination of the transmission frequency channel group is completed. When it is determined in step S704 that the determination of the frequency channel for transmitting the frame is completed, the process of determining that the determination of the transmission frequency channel group is completed ends without transmitting the frame via a frequency channel other than the determined transmission frequency channel group.

[0083] If the communication device 102 determines that the first MAC address group and the second MAC address group are not identical to each other (No in step S703), the process proceeds to step S705. In step S705, the communication device 102 determines that the determination of the transmission frequency channel group is not completed, and the processing flow in this flowchart ends.

[0084] According to this exemplary embodiment, the communication device 102 can determine the frequency channel for transmitting the frame based on the STA that has not established a connection using the frequency channel of the channel determined to be used for transmitting the frame and the number of frequency channels of the STA that has already established a connection with the STA. In addition, determining the frequency channel for transmitting the frame in the above manner can limit the number of frequency channels for transmitting the frame.

[0085] Figure 7 An example of determining completion using the MAC address is shown, but this exemplary embodiment is not limited thereto, and multi-link information to be shared when the AP and the STA establish a connection can be used. In addition, the MAC address of the STA can be used to determine the completion of the determination of the frequency channel for transmitting the frame.

[0086] In the above exemplary embodiment, Figure 3 shows a communication device having Figure 3 the hardware configuration shown executes Figure 6 and Figure 7 the flowcharts in the respective figures in. However, a wireless chip including Figure 3 the storage unit 301, the control unit 302, and the communication unit 306 shown can execute Figure 6 and Figure 7 the flowcharts in the respective figures in. In other words, the communication device according to this exemplary embodiment can be a wireless chip having Figure 3 the storage unit 301, the control unit 302, and the communication unit 306 shown.

[0087] A storage medium storing program code for implementing the above functions can be provided to a system or device, and a computer (CPU or MPU) of the system or device can read and execute the program code stored in the storage medium. In this case, the program code read from the storage medium itself implements the functions of the above exemplary embodiments, and the storage medium storing the program code is included in the above device.

[0088] Available examples of a recording medium for providing program code include 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 DVD.

[0089] In addition, the above functions can be implemented not only by executing the program code read by a computer, but also by the OS running on the computer performing part or all of the actual processing based on the instructions of the program code.

[0090] In addition, the program code read from the storage medium can be written into a memory included in a function expansion board inserted into the computer or a function expansion unit connected to the computer.

[0091] The CPU included in the function expansion board or the function expansion unit can perform part or all of the actual processing based on the instructions of the program code for implementing the above functions.

[0092] According to various embodiments of the present invention, it can also be achieved by supplying a program for implementing one or more functions of the above exemplary embodiments to a system or device via a network or a storage medium and causing one or more processors in the computer of the system or device to read and execute the program. According to various embodiments of the present invention, it can also be achieved by a circuit (e.g., an application specific integrated circuit (ASIC)) that implements one or more functions.

[0093] According to various embodiments of the present invention, when a communication device is connected to a plurality of communication devices and the communication device is connected to at least one communication device via a plurality of frequency channels, it is possible to prohibit an unnecessary frame from being sent to a frequency channel that does not need to receive the frame.

[0094] Other embodiments

[0095] Various embodiments of the present invention can also be implemented as follows: a computer of a system or device that reads and executes computer-executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be more fully referred to as a "non-transitory computer-readable storage medium") to perform the functions of one or more of the above (multiple) embodiments, and / or the system or device includes one or more circuits (e.g., an application specific integrated circuit (ASIC)) for performing the functions of one or more of the above (multiple) embodiments; and a method executed by the computer of the system or device, e.g., reading and executing computer-executable instructions from a storage medium to perform the functions of one or more of the above (multiple) embodiments, and / or controlling the one or more circuits to perform the functions of one or more of the above (multiple) embodiments. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessing unit (MPU)), and may include a network of separate computers or separate processors to read and execute the computer-executable instructions. The computer-executable instructions may be provided to the computer, for example, from a network or a storage medium. The storage medium may include, for example, one or more of a hard disk, a random access memory (RAM), a read-only memory (ROM), a memory of a distributed computing system, an optical disc (such as a compact disc (CD), a digital versatile disc (DVD), or a Blu-ray disc (BD) TM ), a flash device, and a memory card, etc.

[0096] Embodiments of the present invention can also be implemented by the following method, i.e., providing software (a program) that performs the functions of the above embodiments to a system or device via a network or various storage media, and the method by which a computer or a central processing unit (CPU), a microprocessing unit (MPU) of the system or device reads and executes the program.

[0097] Although exemplary embodiments have been described, it should be understood that the present invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is given the broadest interpretation so as to cover all such modifications as well as equivalent structures and functions.

Claims

1. A communication device, comprising: a establishing unit configured to establish a first connection between the communication device and a first other communication device via one or more links using one or more frequency channels, and establish a second connection between the communication device and a second other communication device via one or more links using one or more frequency channels; a determining unit configured to determine a frequency channel required for a frame transmitted in multicast communication or broadcast communication to reach the first other communication device and the second other communication device, wherein the frequency channel is determined from among a plurality of frequency channels used in the links of the first and second connections established by the establishing unit; and a transmitting unit configured to transmit a frame on the frequency channel determined by the determining unit.

2. The communication device according to claim 1, Among them, in a state where the first connection between the communication device and the first other communication device is established by the establishing unit via a first frequency channel and a second frequency channel and the second connection between the communication device and the second other communication device is established by the establishing unit via a third frequency channel and a fourth frequency channel, the determining unit determines each frequency channel in the first frequency channel and the third frequency channel as the frequency channel for transmitting the frame when the first frequency channel and the third frequency channel are the same, and wherein, the transmitting unit transmits the frame on the first frequency channel and the third frequency channel determined by the determining unit.

3. The communication device according to claim 1, Among them, in a state where the first connection between the communication device and the first other communication device is established by the establishing unit via a first frequency channel and the second connection between the communication device and the second other communication device is established by the establishing unit via a second frequency channel and a third frequency channel, the determining unit determines each frequency channel in the first frequency channel and the second frequency channel as the frequency channel for transmitting the frame when the first frequency channel and the second frequency channel are the same, and the determining unit determines each frequency channel in the first frequency channel and one of the second frequency channel and the third frequency channel as the frequency channel for transmitting the frame when the first frequency channel, the second frequency channel, and the third frequency channel are different from each other, and wherein, the transmitting unit transmits the frame on the frequency channel determined by the determining unit.

4. The communication device according to claim 3, wherein, When the first frequency channel, the second frequency channel, and the third frequency channel are different from each other, and when the second frequency channel is a severely congested frequency channel or a frequency channel in which the second other communication device operates in a power saving state, the determining unit determines to transmit the frame onto the third frequency channel.

5. The communication device according to claim 1, wherein, The frame is a group addressed frame.

6. The communication device according to claim 1, wherein, The communication device performs communication conforming to the IEEE 802.11 standard series.

7. A method for a communication device, the method comprising: establishing a first connection between the communication device and a first other communication device via one or more links using one or more frequency channels, and establishing a second connection between the communication device and a second other communication device via one or more links using one or more frequency channels; Determine a frequency channel required for a frame transmitted in multicast communication or broadcast communication to reach a first other communication device and a second other communication device, where the frequency channel is determined from among a plurality of frequency channels used in the links of the established first and second connections; and Transmit a frame on the determined frequency channel.

8. A non-transitory computer-readable storage medium storing a program for causing a computer to perform a method for a communication device, the method comprising: Establish a first connection between the communication device and a first other communication device using one or more frequency channels via one or more links, and establish a second connection between the communication device and a second other communication device using one or more frequency channels via one or more links; Determine a frequency channel required for a frame transmitted in multicast communication or broadcast communication to reach a first other communication device and a second other communication device, where the frequency channel is determined from among a plurality of frequency channels used in the links of the established first and second connections; and Transmit a frame on the determined frequency channel.

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