Communication device, control method, and computer-readable storage medium

Abstract

Communication apparatus, control method, and computer-readable storage medium. The communication apparatus performs communication by establishing a first radio link with a partner apparatus using a first frequency; determines whether or not interference with a specific radio wave occurs in the first radio link; in a case where it is determined that interference occurs in the first radio link, controls to perform first processing in a case where communication can be performed by establishing a plurality of radio links with the partner apparatus, and controls to perform second processing in a case where communication cannot be performed by establishing a plurality of radio links with the partner apparatus, thereby continuing communication that has been performed in the first radio link using a second radio link established using a second frequency different from the first frequency.

Description

Technical Field

[0001] This invention relates to communication devices, control methods, and computer-readable storage media, and particularly to communication control technology in wireless communication. Background Technology

[0002] With the recent increase in the amount of data to be communicated, communication technologies such as Wireless Local Area Networks (LANs) have been developed. The Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard family is well-known as the primary wireless LAN communication standard. The IEEE 802.11 standard family includes standards such as IEEE 802.11a / b / g / n / ac / ax. For example, the latest IEEE 802.11ax standard standard standardizes a technology that uses Orthogonal Frequency Division Multiple Access (OFDMA) to achieve a peak throughput of up to 9.6 gigabits per second (Gbps) and improves communication speed under congested conditions (see Reference 1).

[0003] On the other hand, to further improve throughput, frequency utilization efficiency, and communication latency, a task group was formed as a successor to IEEE 802.11ax (referred to as IEEE 802.11be). In IEEE 802.11be, a technique has been investigated that allows communication devices (e.g., access points (APs)) to simultaneously transmit radio signals to a single STA (station) using frequency bands including the 2.4 GHz, 5 GHz, and 6 GHz bands. This improves throughput compared to using a single frequency band according to conventional standards. Furthermore, latency can be reduced by selectively using, for example, certain uncongested bands from multiple bands. Additionally, using multiple frequency bands simultaneously allows for more efficient use of radio frequency space than increasing bandwidth within a single band.

[0004] Citation List

[0005] Patent documents

[0006] Reference 1: Japanese Patent Application No. 2018-050133

[0007] Reference 2: Japanese Patent Application No. 2019-036776 Summary of the Invention

[0008] Technical issues

[0009] This invention provides a method for efficiently performing channel setting control when using multiple frequency bands simultaneously, and more generally, when using multiple channels of one or more frequency bands simultaneously.

[0010] Solution to the problem

[0011] According to one aspect of the present invention, a communication apparatus is provided, comprising a communication unit for performing communication by establishing a first radio link with a counterpart device using a first frequency, a determining unit for determining whether interference with a specific radio wave occurs in the first radio link, and a control unit for controlling, in the case that interference is determined to occur in the first radio link, to perform a first process if communication can be performed by establishing multiple radio links with the counterpart device, and to perform a second process if communication cannot be performed by establishing multiple radio links with the counterpart device, thereby continuing communication performed in the first radio link using a second radio link established at a second frequency different from the first frequency.

[0012] Beneficial effects of the invention

[0013] According to the present invention, channel setting control can be performed efficiently when multiple channels in one or more frequency bands are used simultaneously.

[0014] Other features and advantages of the invention will become clear from the following description with reference to the accompanying drawings. Note that throughout the drawings, the same reference numerals denote the same or similar parts. Attached Figure Description

[0015] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the specification, serve to explain the principles of the invention.

[0016] Figure 1 This is a view that displays an instance of the network configuration;

[0017] Figure 2 This is a block diagram illustrating an example of the functional configuration of the AP and STA;

[0018] Figure 3 This is a block diagram illustrating an example of the hardware configuration of the AP and STA;

[0019] Figure 4 This is a flowchart illustrating an example of the processing procedures performed at the start of communication;

[0020] Figure 5 This is a timing diagram illustrating an example of a communication process;

[0021] Figure 6 This is a view showing an example of a multi-band element format;

[0022] Figure 7 This is a view that shows instances of the band ID field;

[0023] Figure 8 This is a flowchart illustrating a first instance of the processing procedures performed after communication begins;

[0024] Figure 9 This is a view showing an example of the format of the channel switching announcement elements;

[0025] Figure 10 This is a view showing an example of a radio frequency change notification format including the BSSID;

[0026] Figure 11 This is a flowchart illustrating a second instance of the processing procedure performed after communication begins. Detailed Implementation

[0027] The embodiments will now be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the invention. Multiple features are described in the embodiments, but this does not limit the invention to requiring all of these features, and multiple such features can be suitably combined. Furthermore, in the drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions thereof are omitted.

[0028] (Network Configuration)

[0029] Figure 1 An example of the configuration of a wireless communication network according to this embodiment is shown. The wireless communication network is configured to include an access point (AP 102) and a terminal (STA 103). Both communication devices are communication devices capable of performing wireless communication conforming to the IEEE 802.11be standard, and can even be configured to perform wireless communication conforming to standards established prior to the IEEE 802.11be standard. Figure 1 In this configuration, AP 102 can establish a connection with STA 103 (as a counterpart device) located within a nearly circular area 101 centered on AP 102, and perform wireless communication (transmission / reception of radio signals). AP 102 can, for example, form a wireless communication network within area 101. Note that area 101 can cover a wider range or only a narrower range. Figure 1A wireless communication network comprising one AP and one STA is shown as an example. Each of these communication devices can have two or more. Additionally, for example, STAs conforming only to standards prior to IEEE 802.11be can exist in the network and can connect to AP 102 to perform communication. Note that AP 102 and STA 103 can communicate with each other by simultaneously using multiple radio bands or by selectively using some of the multiple radio bands. Note that when using two or more radio bands simultaneously, multiple radio links can be established between AP 102 and STA 103 to perform communication.

[0030] (AP and STA configuration)

[0031] Figure 2 This is a block diagram illustrating the functional configuration of AP 102 and STA 103. Each of AP 102 and STA 103 includes a first wireless LAN control unit 201, a second wireless LAN control unit 206, and a third wireless LAN control unit 207, configured to control wireless LAN communications in three frequency bands, including, for example, 2.4 GHz, 5 GHz, and 6 GHz bands. However, these are merely examples. For instance, wireless LAN control with respect to multiple frequency bands can be performed using a common wireless LAN control unit, and two or fewer wireless LAN control units can be prepared. Furthermore, to handle more frequency bands or to perform more distributed communication control within a single frequency band, four or more wireless LAN control units can be prepared. These wireless LAN control units perform wireless LAN communication control according to various procedures defined in the IEEE 802.11 standard family. Note that in this embodiment, these wireless LAN control units conform to the IEEE 802.11be standard. Each wireless LAN control unit can be implemented using an antenna, circuitry, and a program configured to control them, the antenna and circuitry being configured to send / receive radio signals to / from another communication device with wireless LAN communication capabilities.

[0032] AP 102 and STA 103 each also include a frame generation unit 202, a frame analysis unit 203, a UI control unit 204, and a storage unit 205.

[0033] Frame generation unit 202 generates radio frames to be transmitted by each of the aforementioned wireless LAN control units. The radio frames are configured to include predetermined control information, regardless of whether user data is included. The content of the control information generated by frame generation unit 202 can be limited by settings stored in storage unit 205. Furthermore, the content of the control information can be changed by user settings from UI control unit 204. Frame analysis unit 203 interprets the frames received by the wireless LAN control units and extracts the data included in the frames. If the received frames include content related to wireless LAN control, this content will be reflected on each wireless LAN control unit. When frame analysis unit 203 extracts the control information included in a frame received by one of the wireless LAN control units, other wireless LAN control units that have not received the frame can perform control based on that control information.

[0034] The UI control unit 204 is implemented through hardware associated with a user interface and a program configured to control them, such as a touch panel and buttons for accepting user operations on AP 102 and STA 103. Note that the UI control unit 204 also has the function of presenting information to the user (e.g., image display or audio output). The storage unit 205 is a storage device that can be implemented by ROM and RAM, which are configured to store data and programs for operating the AP.

[0035] Figure 3 This is a block diagram illustrating the hardware configuration of AP 102 and STA 103. As an example of the hardware configuration, each of AP 102 and STA 103 includes a storage unit 301, a control unit 302, a function unit 303, an input unit 304, an output unit 305, a communication unit 306, and radio antennas 307 to 309.

[0036] Storage unit 301 is formed by either or both of ROM and RAM, and stores programs configured to perform various operations described later, as well as various information such as communication parameters for wireless communication. Here, "ROM" is an abbreviation for Read-Only Memory, and "RAM" is an abbreviation for Random Access Memory. Note that storage unit 301 can be used not only with memories such as ROM or RAM, but also with storage media such as floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, or DVDs.

[0037] The control unit 302 is formed by, for example, at least one processor (such as a CPU or MPU), an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a field-programmable gate array (FPGA), etc. Here, "CPU" is an abbreviation for Central Processing Unit, and "MPU" is an abbreviation for Microprocessor Unit. The control unit 302 executes the program stored in the storage unit 301, thereby controlling the entire device (e.g., AP 102 or STA 103). Note that the control unit 302 can control the entire AP 102 through the cooperation of the program stored in the storage unit 301 and the operating system (OS).

[0038] Furthermore, the control unit 302 controls the functional unit 303 and performs predetermined processes such as imaging, printing, or projection. The functional unit 303 is the hardware that performs the predetermined processes on the AP 102 / STA 103. For example, if the AP 102 / STA 103 is a camera, then the functional unit 303 is an imaging unit and performs imaging processing. Similarly, for example, if the AP 102 / STA 103 is a printer, then the functional unit 303 is a printing unit and performs printing processing. Furthermore, for example, if the AP 102 / STA 103 is a projector, then the functional unit 303 is a projection unit and performs projection processing. The data processed by the functional unit 303 may be data stored in the storage unit 301, or it may be data communicated with another AP or STA via the communication unit 306, described later.

[0039] Input unit 304 accepts various operations from the user. Output unit 305 performs various outputs to the user. Here, the output of output unit 305 includes at least one of, for example, display on a screen, audio output from a speaker, and vibration output. Note that both input unit 304 and output unit 305 can be implemented by a single module, like a touch panel. Furthermore, each of input unit 304 and output unit 305 can be incorporated into AP 102 / STA 103, or can be configured for external attachment.

[0040] Communication unit 306 controls wireless communication or controls IP communication conforming to the IEEE 802.11 family of standards. Communication unit 306 is a so-called radio chip, which may itself include one or more processors or memories. In this embodiment, communication unit 306 can perform processing conforming to at least the IEEE 802.11be standard. Additionally, communication unit 306 controls antennas 307 to 309 and transmits / receives radio signals for wireless communication. AP 102 / STA 103 communicates with another communication device via communication unit 306, providing content such as image data, document data, or video data. Each of antennas 307 to 309 is an antenna configured to transmit / receive radio signals in, for example, one of the 2.4 GHz band, 5 GHz band, and 6 GHz band. Note that there is no particular limitation on the frequency bands (and combinations thereof) processed by antennas 307 to 309. Each of antennas 307 to 309 can be a single antenna or can be configured to include two or more antennas to perform multiple-input multiple-output (MIMO) transmission / reception. Figure 3 At least three antennas 307 to 309 are shown. However, the invention is not limited thereto. For example, when using a multi-band antenna supporting at least two of the aforementioned frequency bands, the AP 102 / STA 103 may include only one or two antennas. Alternatively, the AP 102 / STA 103 may include more antennas.

[0041] (Processing procedure)

[0042] In this embodiment, AP 102 and STA 103 can be connected in each of the 2.4 GHz band, 5 GHz band, and 6 GHz band, and they perform wireless communication using at least one of these bands. In this case, a configuration can be made such that if interference is detected in a certain band, communication between AP 102 and STA 103 in that band is restricted. For example, if interference is detected in a predetermined band, AP 102 switches communication from the predetermined band to another band. This process will be described below.

[0043] Figure 4 An example of the communication initiation process performed by AP 102 (or STA 103 in some cases) in this embodiment is shown. Figure 4 The processing shown can be implemented by executing a program stored in the storage unit 301 through a control unit 302, such as AP 102 (or STA 103 in some cases). Note that it is possible to prepare to implement... Figure 4 The processing shown can be performed by dedicated hardware, or, for example, by the communication unit 306 of AP 102 (or STA 103 in some cases), through a chip or the like disposed in the communication unit 306. Figure 4 The processing shown. Figure 5 An example of the communication process between AP 102 and STA 103 according to this embodiment is shown. Note that it is assumed here that management frames (e.g., signals for connection processing) are transmitted / received only in the 2.4 GHz band. That is, control frames in the 2.4 GHz band control connection and disconnection in other bands. Since there is no unnecessary transmission / reception of control frames in each band, radio resources can be used efficiently. Note that this is an example, and control frame transmission / reception can be performed in the 5 GHz band or the 6 GHz band. For example, in a state where the 2.4 GHz band is unavailable, control frame transmission / reception can be performed in the 5 GHz band or the 6 GHz band. In any case, for example, when communication control in some bands is controlled by control frames transmitted / received in another band, radio resources can be used efficiently.

[0044] First, AP 102 determines which frequency bands are available (step S401). In one example, AP 102 can determine the available frequency bands based on the congestion level of the surrounding radio environment. For example, AP 102 can determine that frequency bands with a congestion level of a predetermined value or higher cannot be used. AP 102 can determine that frequency bands with a congestion level below the predetermined value are available. In this case, for example, AP 102 can add up the number of responses received for each probe request sent in each frequency band and estimate the congestion level of the frequency band. AP 102 can add up the number of beacons observed in each frequency band within a predetermined time period to estimate the congestion level of the frequency band. AP 102 can estimate the congestion level of each frequency band by adding up the number of carrier detections within the predetermined time period or by exchanging information with another AP. Alternatively, AP 102 can determine the available frequency bands based on an index different from the congestion level of each frequency band. For example, determining that frequency bands with noise levels below a predetermined level in a no-signal state are available, thereby determining the available frequency bands. Note that in the following text, it is assumed that AP 102 determines that the 2.4GHz band, 5GHz band, and 6GHz band are all available.

[0045] After determining the available frequency bands, AP 102 uses, for example, beacon frames to transmit available frequency band information (steps S401 and S501). Here, for example, the available frequency band information is added to the frequency band ID of the multi-band element of the beacon frame and transmitted. Note that AP 102 transmits beacon frames periodically according to the beacon interval in one of the available frequency bands. The beacon interval is typically 100 milliseconds, but is not limited to this. The available frequency band information may include information indicating the frequency band used to transmit the beacon frame, or it may not include information about the frequency band. For example, a beacon transmitted in the 2.4 GHz band may include information indicating the 5 GHz and 6 GHz bands as available frequency band information. Similarly, a beacon transmitted in the 5 GHz band may include information indicating the 2.4 GHz and 6 GHz bands as available frequency band information, and a beacon transmitted in the 6 GHz band may include information indicating the 2.4 GHz and 5 GHz bands as available frequency band information.

[0046] Note that available frequency band information can be included in a frame different from the beacon frame. For example, available frequency band information can be included in a probe response, authentication response, association response, or reassociation response sent by AP 102. Furthermore, STA 103 can send a probe request, authentication request, association request, or reassociation request to AP 102 that includes its own available frequency band information.

[0047] Available frequency band information can be obtained from Figure 6 The multi-band element format is shown. Here, the part associated with this embodiment is band ID 604. Note that the remaining parts are the same as in the conventional standard, and their description will be omitted here. In this embodiment, the value representing the information of available band combinations is redefined as the value stored in band ID 604. For example, as Figure 7As shown, the value "8" stored in band ID 604 is defined as a value representing a combination of the 2.4 GHz and 5 GHz bands. Furthermore, the value "9" is defined as a value representing a combination of the 2.4 GHz and 6 GHz bands, the value "10" is defined as a value representing a combination of the 5 GHz and 6 GHz bands, and the value "11" is defined as a value representing a combination of the 2.4 GHz, 5 GHz, and 6 GHz bands. Note that this is merely an example, and, for example, any values ​​or information fields defined in association with available bands can be used. For example, multiple multi-band elements can be added to the beacon. For instance, if the 2.4 GHz band, 5 GHz band, and 6 GHz band are determined to be available bands, then a multi-band element including three band IDs 604 (stored with values ​​"2", "4", and "7" respectively) is added to the beacon.

[0048] When adding multiple multi-band elements to a beacon, AP 102 can store information about the operable radio bands by combining the Operating Class 605 and the Channel Number 606. For example, in Europe, if AP 102 is used in Channel = 5, Channel = 36, and Channel = 220, the Operating Class 605 and Channel Number 606 can be set as follows: First, in the multi-band element indicating operation in the 2.4 GHz band, the value of Band ID 604 is set to "2", the value of Operating Class 605 is set to "30", and the value of Channel Number 606 is set to "5". Furthermore, in the multi-band element indicating operation in the 5 GHz band, the value of Band ID 604 is set to "4", the value of Operating Class 605 is set to "5", and the value of Channel Number 606 is set to "36". Furthermore, in the multi-band element indicating its operation in the 6 GHz band, the value of band ID 604 is set to "7", the value of operation class 605 is set to "19", and the value of channel number 606 is set to "220". This can even indicate, for example, the use of different radio channels within the same band by AP 102. For example, multiple multi-band elements are prepared when using channel = 5, channel = 36, and channel = 136 to represent information about available channels. Note that in the following text, the symbol "ch" can be used to indicate the number of a specific radio channel. For example, the radio channel with channel = 36 can be represented as "36ch" without special specification.

[0049] AP 102 establishes a connection with STA 103 based on the available frequency band information transmitted (step S403). For example, STA 103 uses one of the frequency bands available to it to send a probe request and begins a scanning operation (S502). Note that in this embodiment, it is assumed that STA 103 sends a probe request in the 2.4 GHz frequency band. In response to the probe request, STA 103 receives a probe response from AP 102 using the frequency band used to send the probe request (S503). In this example, STA 103 can detect the frequency that AP 102 can process and the radio channel operating at that frequency based on the value of the frequency band ID included in the probe response. Afterwards, STA 103 sends an authentication request to AP 102 (S504) and receives an authentication response from AP 102 (S505). Subsequently, when STA 103 sends an association request to AP 102 (S506) and receives an association response from AP 102 (S507), a connection is established between AP 102 and STA 103. Note that in this embodiment, the case of establishing a connection in an unencrypted state will be described. However, the invention is not limited to this. In order to establish a secure connection using encryption between AP 102 and STA 103, communication processing such as Wi-Fi Protected Access (WPA) or WPA2 (not shown) can be performed afterward. Furthermore, in order to perform WPA3 processing, SAE Commit and SAE Confirmation can be sent when sending / receiving authentication requests. In this case, a four-way handshake can be performed after sending / receiving the association request and association response. STA 103 can establish a connection in two or more available frequency bands. For example, if there are three available frequency bands, two or all of them can be used to establish a connection. For example, the STA 103 can transmit probe requests not only in the 2.4 GHz band, but also in the 5 GHz band or the 6 GHz band.

[0050] After a connection is established, AP 102 and STA 103 can determine the transmission / reception parameters (steps S404 and S508). If multiple connections are established, the transmission / reception parameters are information used to determine how to distribute transmission / reception data to each connection. For example, the amount of data distributed can be determined based on the maximum throughput available in each frequency band or by actually transmitting / receiving test packets and calculating the current throughput. This value can be changed as needed. For example, after a predetermined period of data transmission / reception, the amount of data distributed for the next predetermined period can be determined based on the actual amount of data transmitted / received. Additionally, the frequency bands for transmitting / receiving control packets and data packets can be separated. For example, it can be set up such that management frames for control are transmitted / received in the 2.4 GHz frequency band, and data frames are transmitted / received in the 5 GHz and 6 GHz frequency bands. Furthermore, for example, in communications used for applications such as Mixed Reality or Augmented Reality, the frequency bands for transmitting / receiving information for application control can be separated from the frequency bands for transmitting / receiving other information. For example, location information, attitude information, and delay control information can be transmitted / received in the 2.4 GHz band, and content information and occlusion information for obstructing visible objects can be transmitted / received in the 5 GHz or 6 GHz band. Additionally, when transmitting / receiving camera images, metadata such as date / time data or photo parameters can be transmitted / received in the 2.4 GHz band, and pixel information can be transmitted / received in both the 5 GHz and 6 GHz bands. Transmit / receive parameter determination processing can be omitted. For example, different streams can be transmitted / received independently in connections corresponding to specific frequency bands.

[0051] Subsequently, AP 102 and STA 103 transmit / receive data using the determined transmit / receive parameters (steps S405, S511, S512, S521, S522, S531, and S532). Here, the state in which data transmission / reception can be performed is referred to as the state in which a radio link is established. At this point, it is assumed that the radio link is established in 5 channels of the 2.4 GHz band, 36 channels of the 5 GHz band, and 220 channels of the 6 GHz band.

[0052] Here, in the 5 GHz band, it is assumed that this band is used for weather observation radar or military radar. Therefore, interference to them must be suppressed. Thus, the standard IEEE 802.11 series defines an interference avoidance technique called Dynamic Frequency Selection (DFS) for communication in the 5 GHz band (see Reference 2). According to DFS, interference with radio waves for another specific application purpose, such as weather observation radar, can be prevented. Similarly, even in other frequency bands besides the 5 GHz band, it can be assumed that radio waves are used for applications where interference should be avoided. In an example, it is assumed that if a predetermined communication with high priority is being performed, interference with that predetermined communication should be avoided. In this case, the following process can be performed. The high-priority communication is for a predetermined application such as an emergency call. By analyzing the header of the radio frame, AP 102 or STA 103 can identify that this communication is being performed. Interference avoidance via DFS can also be performed in these frequencies. However, during channel switching via DFS, it is necessary to confirm whether interference has occurred within 60 seconds in the switched channel. Therefore, the time before communication is restored is long.

[0053] In this embodiment, if AP 102 (or STA 103 in some cases) can establish multiple radio links in multiple frequency bands (or multiple channels of one or more frequency bands), then processing is performed to continue communication while effectively avoiding interference. That is, if it is determined, for example, by detecting radio waves for a specific application purpose that interference will occur in one of the multiple available frequency bands, then communication continues in another frequency band. For example, AP 102 (or STA 103 in some cases) performs processing using a frequency band different from the frequency band where interference will occur, without switching the settings of available frequency bands.

[0054] Figure 8 An example of the processing procedures performed in each radio link after communication has begun is shown. Figure 8 The processing shown can be implemented by a control unit 302, such as AP 102 (or in some cases STA 103), executing a program stored in storage unit 301. Note that it can be prepared for implementation. Figure 8 The processing shown can be performed by dedicated hardware, or, for example, by the communication unit 306 of AP 102 (or STA 103 in some cases), through a chip or the like disposed in the communication unit 306. Figure 8 The process is illustrated here. An example of the process in a 36-channel radio link in the 5 GHz band will be described. However, this is merely an example; the same process can be performed even in the 2.4 GHz or 6 GHz bands. Note that this process is performed on a link-by-link basis. That is, if, for example, multiple radio links are established in different channels in the 5 GHz band, the process is performed simultaneously on the radio links. Figure 8 The processing shown.

[0055] First, AP 102 determines whether interference with another specific radio wave (radio wave of a specific radio system) has occurred in 36ch (step S801). AP 102 performs this determination by, for example, executing specific radar detection processing (such as DFS function). When it is determined that interference with the specific radio wave has occurred in 36ch ("Yes" in step S801), AP 102 proceeds to step S802. On the other hand, if it is not determined that interference with the specific radio wave has occurred in 36ch ("No" in step S801), AP 102 continues to monitor for interference.

[0056] In step S802, AP 102 determines whether it can communicate in a multi-link environment. If AP 102 can communicate in a multi-link environment ("Yes" in step S802), AP 102 proceeds to step S804. If AP 102 cannot communicate in a multi-link environment ("No" in step S802), AP 102 proceeds to step S803. This determination in step S802 can be achieved, for example, by determining whether AP 102 includes a configuration that enables multi-link communication in at least one of its hardware and software. For example, if multi-link communication is physically unavailable, such as when each radio antenna configured in AP 102 corresponds only to a single frequency band, AP 102 determines that multi-link communication cannot be performed ("No" in step S802). Furthermore, if AP 102 does not have sufficient available RAM and multi-link communication is not possible, AP 102 determines that multi-link communication cannot be performed ("No" in step S802). Note that standards such as antenna performance or RAM are merely examples, and other standards may also be used. For instance, if the peer device (STA 103) connected to AP 102 does not have multilink communication capability, it can be determined that multilink communication with the peer device is not possible. In this case, if the peer device (STA 103) connected to AP 102 has multilink communication capability, it can be determined that multilink communication with the peer device is possible. If this determination standard is used, AP 102 can perform different processing for each peer device (one of steps S803 and S804 described later). Furthermore, if the result changes depending on the peer device, AP 102 can perform the processing of steps S803 and S804. Note that whether the connected peer device (STA 103) has multilink communication capability can be obtained, for example, from the device capability information (Capability Information) sent by the peer device at the time of connection. The presence / absence of this capability can be determined based on whether the peer device is able to perform communication corresponding to a specific standard (e.g., the IEEE 802.11be standard).

[0057] If a predetermined determination result is obtained independently of the following situations, such as always determining that multi-link communication cannot be performed due to factors such as the antenna, or always determining that multi-link communication can be performed due to sufficient resources such as the antenna and RAM, then step S802 can be omitted. In this case, if it is always determined that multi-link communication cannot be performed, step S803 is performed instead of step S804. Alternatively, if it is always determined that multi-link communication can be performed, step S804 is performed instead of step S803. Note that in this embodiment, AP 102 establishes radio links with STA 103 in the 2.4 GHz band, 5 GHz band, and 6 GHz band, and determines in step S802 that multi-link communication can be performed.

[0058] Step S803 is a process performed when AP 102 cannot perform multi-link communication. In this case, since AP 102 is only connected to STA 103 in 36 channels of the 5GHz band, it is necessary to change the channel used from that channel to another channel. Therefore, AP 102 sends a radio frequency change notification to STA 103 to change the radio frequency to be used. For example, AP 102 sends a radio frame that includes elements called Channel Switch Announcement as defined in the IEEE 802.11 standard series. Figure 9 The structure of this element is shown. Figure 9 In the field shown, new channel number 904 stores a value indicating the radio channel number to be used after the change. Therefore, after the channel to be used changes to the channel represented by the value stored in new channel number 904, AP 102 and STA 103 continue communicating. Note that although an example of notifying a radio frequency change via a channel switch announcement element is described here, this notification can also be achieved using another element. For example, the Extended Channel Switch Announcement element can be used to notify of a radio frequency change.

[0059] Step S804 is a process performed when AP 102 is capable of multi-link communication. In this case, AP 102 can establish a radio link with STA 103 using channels other than 36 channels in the 5 GHz band. Therefore, AP 102 sends the network identifier (BSSID) of the Basic Service Set (BSS) to STA 103 and performs communication within the BSS, which operates at high communication quality radio frequencies in the available frequencies. For example, AP 102 can notify STA 103 of the BSSID corresponding to the radio frequency with the highest communication quality among the available frequencies. AP 102 can specify radio frequencies in the available frequencies with communication quality exceeding a predetermined value and notify STA 103 of the BSSID corresponding to randomly selected radio frequencies or radio frequencies that meet specific criteria (e.g., the lowest frequency among the radio frequencies). Here, high communication quality radio frequencies can be specified based on values ​​that directly represent radio quality (e.g., signal-to-noise ratio (SNR) or received signal strength indicator (RSSI)). However, the invention is not limited to this; radio frequencies with a high estimated communication quality can be specified. For example, the fewer the number of established connections, the fewer communications to be performed, and the lower the frequency of interference, the higher the estimated communication quality of the radio frequency. Therefore, radio frequencies can be selected based on these conditions. In an example, a radio frequency with zero established connections can be selected. Additionally, a radio frequency that is not the target of DFS can be selected. Radio frequencies can be selected by combining these factors.

[0060] AP 102 can further add BSSID information to the channel handover announcement element, for example (e.g.) Figure 10(As shown) and sends a radio frame including the element to STA 103 to perform this notification. AP 102 can perform this notification by adding the BSSID to another existing element and sending that element, or by including the BSSID in an element that is not currently defined and sending that element. Note that in this embodiment, an example of a notification corresponding to a BSSID of a radio frequency is described. However, the invention is not limited to this, and any information that allows STA 103 to specify the radio frequency that AP 102 can perform communication can be notified to STA 103. For example, an Extended Service Set ID (ESSID) or a Media Access Control (MAC) address can be notified to STA 103. In this way, AP 102 can notify STA 103 to perform communication in 36ch of the 5GHz band in a radio link on another channel. Note that in step S804, information indicating the channel in which a radio link between AP 102 and STA 103 has not been established can be notified. In this situation, STA 103 can establish a new radio link outside the currently established radio link based on received information such as BSSID, and switch communication to the newly established radio link.

[0061] As described above, in an environment where multiple radio links among multiple radio frequencies are available, if interference to a specific radio wave occurs in a predetermined frequency band, information specifying a high-quality wireless frequency among the multiple wireless frequencies is sent from AP 102 to STA 103. When communication continues using the specified radio frequency, communication can continue while preventing interference in the radio link during the communication state, without performing radio frequency change processing in AP 102. That is, in the event of interference in communication in some frequency bands of multiple available frequency bands, communication is performed in another frequency band of multiple frequency bands, thereby easily continuing communication while preventing interference. In addition, when switching the frequency band to be used among the multiple available frequency bands, the time before communication can continue can be shortened. For example, in a conventional DFS, after switching radio frequencies based on interference detection, it is necessary to scan and confirm whether there is no interference in the radio frequency of the switching destination within 60 seconds. On the other hand, in this embodiment, since interference detection is performed repeatedly in other available frequency bands in advance, a post-switching scan is not performed, and communication can continue in the available frequency bands.

[0062] Note that the above process illustrates an example where, in the frequency band where interference occurs, AP 102 notifies STA 103 of information specifying another available frequency band. On the other hand, in the case where multiple radio links are established in multiple frequency bands, when the interfering radio link is disconnected, communication can continue using a radio link in another frequency band that remains open while preventing further interference. (Refer to...) Figure 11 Describe the processing procedure. Note that... Figure 11 The process shown can be implemented by executing a program stored in the storage unit 301 through a control unit 302, such as AP 102 (or STA 103 in some cases). Additionally, preparations can be made for implementation. Figure 11 The processing shown can be performed by dedicated hardware, or, for example, by the communication unit 306 of AP102 (or in some cases STA 103), through a chip or the like disposed in the communication unit 306. Figure 11 The processing shown.

[0063] Steps S801 to S803 and Figure 8The process shown is the same, and its description will be omitted. AP 102 determines whether there is a radio link with STA 103 other than the radio link being processed (step S1101). For example, AP 102 determines whether to connect to STA 103 using a channel other than, for example, 36 channels in the 5GHz band. In this embodiment, AP 102 establishes a connection with STA 103 in 5 channels of the 2.4GHz band or 220 channels of the 6GHz band. Therefore, in the processing for 36 channels of the 5GHz band, AP 102 determines that there is a radio link established with STA 103 other than the radio link being processed ("Yes" in step S1101). In this case, AP 102 disconnects the radio link for 36 channels of the 5GHz band without notifying STA 103 of the changed radio link information (step S1102). At this time, other radio links remain unchanged and are not disconnected. Therefore, even if a radio link is disconnected, another radio link is established between AP 102 and STA 103. Therefore, communication can continue. Note that if data is being communicated in the radio link of the target being processed, the data can be discarded or sent / received via another radio link. On the other hand, in processing for 36 channels in the 5GHz band, if no connection to STA103 is established in any other radio link besides 36 channels ("No" in step S1101), AP 102 will proceed to step S803 to perform a switch of the radio frequency to be used. In this case, if, for example, DFS is met, a predetermined time period is generated to determine whether interference with a specific radio wave occurs in the switched channel. Note that in this case, a new communication link can be established by sending the BSSID, just like... Figure 8 As in step S804 of the example. As described above, if multiple radio links are established in multiple frequency bands (or multiple radio channels), AP 102 and STA 103 can easily prevent interference by disconnecting communication in the channel where radio waves interfering with the specific application purpose are occurring. Furthermore, at this time, communication can continue using another connected channel, allowing for efficient and continuous communication without performing channel switching processing.

[0064] Note that the above description refers to the process performed by AP 102, but STA 103 can also perform this process. That is, when AP 102 determines that interference with radio waves for a specific application purpose has occurred, the process performed by AP 102 can also be performed by STA 103. Therefore, in the case where AP 102 does not detect interference but STA 103 detects interference, communication can continue while appropriately changing the frequency band used to suppress interference. Furthermore, in the above process, for example, if communication continues in the 2.4GHz band or the 6GHz band based on the occurrence of interference in channel 36 of the 5GHz band, the use of the 5GHz band is stopped. At this time, the availability of another channel in the 5GHz band can be determined. For example, if it is determined that other channels in the 5GHz band besides channel 36 can be used, then the radio link is established using that channel. Therefore, for example, if interference with a specific radio wave occurs in the 2.4GHz band or the 6GHz band thereafter, the 5GHz band can be used as a candidate for an available frequency band. Additionally, for example, the presence / absence of interference can be continuously estimated during periods when communication in the 36th channel of the 5GHz band is not being performed, and it can be determined based on the estimation results whether the 36th channel of the 5GHz band should be reserved as a usable channel.

[0065] Furthermore, in step S1102, within a predetermined time period following the disconnection of the radio link in the 36th channel of the 5GHz band, AP 102 (or STA 103) can monitor for any interference with the specific radio wave. If no interference with the specific radio wave occurs within this predetermined time, AP 102 (or STA 103) can re-establish the radio link in the 36th channel of the 5GHz band. In this case, AP 102 (or STA 103) can transmit (send and / or receive) signals for re-establishing the radio link in the 36th channel of the 5GHz band in the 2.4GHz band or 6GHz band where communication continues.

[0066] As described above, when interference is detected in the first radio link during communication, and if the device supports multi-link communication, AP 102 (or STA 103) performs a first process, such as notifying the BSSID or disconnecting the first radio link. Conversely, if the device does not support multi-link communication, AP 102 (or STA 103) performs a second process, such as sending a radio frame including a channel switching notification element. In both cases, communication performed on the first radio link continues using a second radio link on a different frequency band (channel) than the first radio link. Therefore, AP 102 / STA 103, which has the capability to establish multiple radio links, can quickly and efficiently continue communication using multiple radio links without changing the available frequency band settings. On the other hand, although channel switching takes a relatively long time, AP 102 / STA 103, which does not have the capability to establish multiple radio links, can also continue communication by switching the channel to be used.

[0067] Note that the above embodiments assume wireless communication conforming to the IEEE 802.11 standard series. However, the present invention is not limited thereto. That is, the above technology can be applied to wireless communication devices capable of establishing multiple radio links with a counterpart device simultaneously using different frequency bands (channels). For example, if the communication device has the function of establishing multiple radio links to perform communication when interference is determined to occur, then the radio link to be used to continue communication is specified among the multiple radio links, and information such as the network identifier of the radio link is notified to the counterpart device. On the other hand, if the communication device does not have the function of establishing multiple radio links to perform communication, then information indicating the changed channel is notified to the counterpart device. Therefore, if multiple radio links can be used, communication can be continued quickly and efficiently using multiple radio links while avoiding interference.

[0068] Furthermore, the above embodiments describe an example of continuing communication by changing the channel based on the occurrence of interference. However, the present invention is not limited thereto. For example, the above processing can be performed based on the quality degradation of the radio link in the communication state. That is, the above processing can be performed in any situation where the radio link in the communication state should be changed. In this case, if multiple radio links can be established, processing different from conventional channel switching (e.g., processing such as notifying BSSID) is performed to utilize this capability. Therefore, in various situations where the radio link in the communication state needs to be switched, the communication device (AP 102 / STA 103) capable of using multi-link functionality can efficiently continue communication.

[0069] The present invention can be implemented by providing a program for implementing one or more functions of the above embodiments to a system or device via a network or storage medium, and causing one or more processors in the computer of the system or device to read and execute the program. The present invention can also be implemented by circuitry (e.g., an ASIC) for implementing one or more functions.

[0070] This invention is not limited to the embodiments described above, and various modifications and variations can be made within the spirit and scope of this invention. Therefore, in order to inform the public of the scope of this invention, the following claims are made.

Claims

1. A communication device capable of establishing multiple radio links with a counterpart device, including a first radio link and a second radio link, each of the first radio link and the second radio link using a different channel, the communication device comprising: The first communication unit is used to perform communication with the other device in the first radio link; The second communication unit is used to communicate with the other device in the second radio link; A communication control unit is used to establish multiple radio links with the other device, including the first radio link and the second radio link, based on communication with the associated frame of the other device in the first radio link, and to control communication with the other device in the multiple radio links. A detection unit for detecting predetermined radar radio waves; as well as The disconnection unit is used to disconnect the first radio link when a first radio link and a second radio link have been established with the other device and a predetermined radar radio wave is detected in the channel used for communication performed in the first radio link, wherein... If the detection unit detects a predetermined radar radio wave in the first radio link, the disconnection unit disconnects the first radio link without notifying the other device via the first communication unit to switch to a second radio frame on a different channel than the channel used for communication with the other device in the first radio link. The communication control unit, after disconnecting the first radio link, controls the continuation of such communication using a second radio link, which is the communication performed with the other device on the first radio link.

2. The communication device according to claim 1, wherein, If a first radio link is established with the other device and a predetermined radar radio wave is detected in the channel used for communication with the other device in the first radio link, the communication control unit switches the frequency used for communication in the first radio link to a second channel and controls the use of the second channel to continue communication with the other device in the first radio link.

3. The communication device according to claim 1, wherein, If a first radio link is established with the other device and a predetermined radar radio wave is detected in the channel used for communication with the other device in the first radio link, the communication control unit establishes a second radio link with the other device using a second channel and controls the use of the second radio link to continue communication with the other device performed in the first radio link.

4. The communication device according to claim 1, wherein, If a first radio link and a second radio link have already been established with the other device, the disconnection unit disconnects the first radio link without performing the process of switching channels used to communicate with the other device in the first radio link.

5. The communication device according to claim 2, wherein, The communication control unit selects a channel that is not a target of dynamic frequency selection as the second channel.

6. The communication device according to claim 2, wherein, If a first radio link is established with the other device and a predetermined radar radio wave is detected in the channel used for communication with the other device in the first radio link, the communication control unit performs control to send a radio frame to the other device, the radio frame indicating that the channel used for communication with the other device in the first radio link be switched to a second channel.

7. The communication device according to claim 1, wherein, The radio frame includes channel switching announcement elements conforming to the IEEE 802.11 standard series.

8. The communication device according to claim 1, wherein, The communication control unit controls the execution of communications in accordance with the IEEE 802.11 standard series.

9. A control method for a communication device, the communication device being capable of establishing multiple radio links with a counterpart device, including a first radio link and a second radio link, each of the first radio link and the second radio link using a different channel, the method comprising: To communicate with the other device in the first radio link; To communicate with the other device in the second radio link; Based on the communication of the associated frames with the other device in the first radio link, multiple radio links including the first radio link and the second radio link are established with the other device, and communication with the other device in the multiple radio links is controlled. Detect predetermined radar radio waves; as well as If a first radio link and a second radio link have been established with the other device, and a predetermined radar radio wave is detected in the channel used for communication performed in the first radio link, the first radio link is disconnected, wherein... Upon detection of a predetermined radar radio wave in the first radio link, the first radio link is disconnected without notifying the other device to switch to a second radio frame on a different channel than the channel used for communication with the other device in the first radio link. After disconnecting the first radio link, control is activated to continue such communication using the second radio link, which was performed with the other device in the first radio link.

10. A computer-readable storage medium storing a program configured to cause a computer to perform the steps of the method of claim 9.

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