Communication device, control method, and program

Abstract

When a link on a plurality of different frequency channels is established with another communication device based on a connection request received from the other communication device, the communication device establishes a link on a frequency channel in a millimeter wave band when the link to be established identified based on at least information included in the connection request is only a link on a frequency channel in the millimeter wave band. Control is performed that links on a plurality of different frequency channels are not established based on the connection request.

Description

Technical Field

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

[0002] In recent years, with the increase in the amount of data transmitted, the development of communication technologies such as wireless local area networks (LANs) has been promoted. As the main communication standard for wireless LANs, a series of Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards are known. The series of IEEE 802.11 standards includes standards such as IEEE 802.11a / b / g / n / ac / ax.

[0003] The IEEE 802.11be standard, which is a successor standard to IEEE 802.11ax, is being developed. As a new feature of the IEEE 802.11be standard, functions such as multi-link communication are being studied, in which an access point (AP) and a station (STA) establish multiple links on different frequency channels and communicate in parallel. Patent Document 1 describes a mechanism for establishing multiple links for multi-link communication.

[0004] Citation List

[0005] Patent Document

[0006] PTL 1: Japanese Patent Laid-Open No. 2021-103805 Summary of the Invention

[0007] Technical Problem

[0008] The Ultra High Throughput (EHT) Task Group (TG) is considering operating communication devices compliant with the IEEE 802.11be standard in frequency bands such as the 2.4 GHz band, the 4.9 and 5 GHz bands, and the 6 GHz band. TG is an abbreviation for Task Group. Research on a successor standard to IEEE 802.11be has also started. The Ultra High Reliability (UHR) Study Group (SG) researching the successor standard is considering using frequency bands in millimeter wave bands such as the 45 GHz band and the 60 GHz band to increase the communication throughput of communication devices compliant with the successor standard. SG is an abbreviation for Study Group. The 45 GHz band, the 60 GHz band, etc. are characterized in that they can ensure a wide bandwidth and thus can increase the throughput, but are also characterized in that communication is prone to interruption due to the strong directivity of radio waves. The millimeter wave band thus has a problem that communication is prone to interruption.

[0009] Solution to the Problem

[0010] The present invention has been made in view of at least one of the problems described above. An object of the present invention is to provide a mechanism for establishing a communication link in a frequency band different from the millimeter wave band in addition to a communication link in the millimeter wave band when performing multi-link communication using the communication link in the millimeter wave band.

[0011] A communication device according to an aspect of the present invention includes a control component that is configured to establish a link on a plurality of different frequency channels with another communication device based on a connection request received from the other communication device. When the link to be established identified at least based on the information included in the connection request is only a link on a frequency channel in the millimeter wave band, the control component does not establish a link on a plurality of different frequency channels based on the connection request.

[0012] Advantageous Effects of the Invention

[0013] In this aspect of the present invention, when performing multi-link communication using a communication link in the millimeter wave band, in addition to the communication link in the millimeter wave band, a communication link in a frequency band different from the millimeter wave band can also be established. Therefore, in a propagation environment where communication in the millimeter wave band is not interrupted, high-throughput communication can be expected, and in the case of an interruption, it can be expected that communication continues using the communication link in a different frequency band.

[0014] Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. In the drawings, the same or similar components are denoted by the same reference numerals. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings incorporated in and constituting a part of the specification illustrate embodiments of the present invention and, together with the description, are used to explain the principles of the present invention.

[0016] Figure 1 is a diagram illustrating an exemplary configuration of a network.

[0017] Figure 2 is a diagram illustrating an exemplary hardware configuration of a communication device (AP / STA).

[0018] Figure 3 is a diagram illustrating an example functional configuration of a communication device (AP / STA).

[0019] Figure 4 is a flowchart illustrating an example of control in an AP.

[0020] Figure 5 is a sequence diagram illustrating an example of connection processing.

[0021] Figure 6 is a schematic diagram illustrating an exemplary multi-link element.

[0022] Figure 7 It is a flowchart illustrating an example of control in an STA according to the second embodiment.

[0023] Figure 8 It is a schematic diagram illustrating an exemplary MBO-OCE.

[0024] Figure 9 It is a schematic diagram illustrating an exemplary probe request multi-link element.

[0025] Figure 10 It is a sequence diagram illustrating an example of connection processing according to the third embodiment. Detailed Description of the Embodiment

[0026] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the invention claimed. Although multiple features are described in the embodiments, not all features are essential for the invention, and the features can be combined in any way. In the drawings, the same or similar components are denoted by the same reference numerals and repeated descriptions will be omitted.

[0027] <First Embodiment>

[0028] Figure 1 An exemplary configuration of a network according to this embodiment is illustrated. The network of this embodiment includes an access point device (hereinafter also simply referred to as an AP, AP STA, or access point) and a station device (hereinafter also simply referred to as an STA, non-AP STA, or station). Hereinafter, AP 101 and STA 102 will be collectively referred to as communication devices.

[0029] AP 101 is configured to be capable of transmitting radio frames compliant with a successor standard to the IEEE 802.11be standard, which is designed to achieve a maximum transmission rate of 46.08 Gbps. The successor standard is designed to achieve a maximum transmission rate of 90 Gbps to 100 Gbps or higher. Similarly, STA 102 is configured to be capable of transmitting radio frames compliant with the successor standard. IEEE is an abbreviation for Institute of Electrical and Electronics Engineers. The main features of this successor standard to 802.11be include AP coordination and support for reliable communication and low-latency communication. Based on the above, in this embodiment, the successor standard that is a successor to IEEE 802.11be and is designed to achieve a maximum transmission rate of 90 Gbps to 100 Gbps or higher will also be referred to as IEEE 802.11 Ultra-High Reliability (UHR). The radio frames transmitted according to the successor standard will also be referred to as UHR PPDUs. PPDU is an abbreviation for PLCP Protocol Data Unit, and PLCP is an abbreviation for Physical Layer Convergence Protocol.

[0030] The names IEEE 802.11UHR and UHR standard are given for convenience based on the goals to be achieved by the successor standard and the main features of the standard. Once the standard is finalized, the successor standard may be given a different name. Note that this specification and the appended claims are essentially applicable to communication devices that are compliant with the successor standard to the 802.11be standard and support communication in the millimeter-wave frequency band and multi-link communication (described below).

[0031] Figure 1 A wireless communication network including one AP and one STA is illustrated as an example, but the number of these devices can be greater than the number illustrated. Although AP 101 and STA 101 are configured to support communication (transmission and reception) of UHR PPDUs, they can be configured to support communication of PPDUs compliant with legacy standards prior to the UHR standard. Specifically, AP 101 and STA 102 can be configured to support the transmission and reception of PPDUs compliant with, for example, the IEEE 802.11a / b / g / n / ac / ax / be standards.

[0032] Each communication device is configured to be capable of communicating on operating frequency channels in frequency bands such as the 2.4 GHz band, 3.6 GHz band, 5 GHz band, and 6 GHz band, as well as the 45 GHz band and 60 GHz band, which are referred to as the millimeter-wave band. The frequency bands used by each communication device are not limited to those described above, and different frequency bands (such as the Sub-1GHz band) can be used. In this embodiment, for the purpose of explanation, the frequency band from Sub-1GHz to 10GHz or lower will be uniformly defined as the low-frequency band. However, the definition of the low-frequency band is not limited to this. Among the frequency bands below or equal to 10GHz, only the frequently used frequency bands (such as 2.4GHz, 5GHz, and 6GHz) can be defined as the low-frequency band.

[0033] AP 101 and STA 102 can communicate using bandwidths of 20MHz, 40MHz, 80MHz, 160MHz, 320MHz, 540MHz, 640MHz, 1080MHz, and 2160MHz. The bandwidth used by each communication device is not limited to this, and different bandwidths (such as 240MHz and 480MHz) can be used. Each communication device can be configured such that a bandwidth of 1080MHz or greater can be used only in the millimeter-wave frequency band.

[0034] AP 101 and STA 102 can also be configured to support wireless communication based on other communication standards such as Bluetooth (registered trademark), NFC, and Bluetooth (registered trademark) Low Energy (LE). NFC is an abbreviation for Near Field Communication. AP 101 and STA 102 can be configured to support wired communication using an Ethernet (registered trademark) cable or wired communication using optical fiber. Examples of AP 101 include but are not limited to wireless LAN routers and personal computers (PCs). AP 101 and STA 102 can be information processing devices such as wireless chips that support the transmission and reception of UHR PPDU. Examples of STA 102 include but are not limited to cameras, tablets, smart phones, PCs, mobile phones, video cameras, and wearable devices (such as smart glasses).

[0035] AP 101 and STA 102 can perform multi-link communication involving establishing communication links and communicating through multiple frequency channels. Hereinafter, the communication link will also be simply referred to as a link. An AP that performs multi-link communication will also be referred to as an AP multi-link device (MLD). For example, AP 101 can establish link 103 with STA 102 through a first frequency channel in the 5 GHz band and communicate. In parallel with this, AP 101 and STA 102 can establish link 104 through a second frequency channel in the 60 GHz band and communicate, for example. In this case, STA 102 performs multi-link communication that involves communicating through the second frequency channel in the second link 104 in parallel with communicating through the first frequency channel in link 103. Therefore, by establishing links on multiple different frequency channels with STA 102, AP 101 can increase the throughput in the communication with STA 102.

[0036] For each network in which a link in multi-link communication can be established, each link is assigned a link ID. Assume, for example, that STA 102 participates in the networks in the 5 GHz band and the 60 GHz band among the networks created by AP 101. When the link in the 5 GHz band established between AP 101 and STA 102 is represented by 103, the common link ID = 1 is assigned to this link. Similarly, when the link in the 60 GHz band established between AP 101 and STA 102 is represented by 104, the link ID = 2 is assigned to this link. These values are merely examples. Different values can be assigned to these links, or link IDs can be assigned to each established link or to each STA.

[0037] In the series of IEEE 802.11 standards, the minimum unit of the bandwidth of each frequency channel in the 2.4 GHz band / 5 GHz band / 6 GHz band is defined as 20 MHz. The minimum unit of the bandwidth of each frequency channel in the 45 GHz band is defined as 540 MHz, and the minimum unit of the bandwidth of each frequency channel in the 60 GHz band is defined as 1080 MHz or 2160 MHz. Here, the frequency channel refers to the frequency channel defined in the series of IEEE 802.11 standards. In these standards, multiple frequency channels are defined for each of the frequency bands such as the 2.4 GHz band, 5 GHz band, 6 GHz band, 45 GHz band, and 60 GHz band. By binding to adjacent frequency channels, a bandwidth of 40 MHz or more can be used in one frequency channel. For example, in the 2.4 GHz band / 5 GHz band / 6 GHz band, frequency widths such as 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, 480 MHz, and 640 MHz can be used.

[0038] Despite some limitations, each communication device can be configured to establish multiple links in different frequency bands in multi-link communication. For example, in addition to link 103 in the 5 GHz band and link 104 in the 60 GHz band, AP 101 and STA 102 can also be configured to establish a third link in the 45 GHz band. Alternatively, despite some limitations, AP 101 and STA 102 can be configured to establish links through multiple different channels included in the same frequency band. For example, AP 101 and STA 102 can be configured to establish multiple communication links for multi-link communication with W52 and 36ch in the 5 GHz band as the first link and W53 and 60ch in the 5 GHz band as the second link.

[0039] Despite some limitations, links in the same frequency band and links in different frequency bands can coexist. For example, in addition to establishing link 103 through channel 2 in the 60 GHz band, AP 101 and STA 102 can also establish a link through channel 35 in the 60 GHz band and a link through channel 15 in the 6 GHz band.

[0040] Now, the advantages of establishing multiple links will be described. When AP 101 and STA 102 establish multiple links on different channels, even if one channel is congested, AP 101 can communicate with STA 102 on another channel. Therefore, in the communication with STA 102, a reduction in throughput and communication delay can be prevented.

[0041] Next, the constraints on multi-link communication in this embodiment will be briefly described. For example, the 45 GHz band and the 60 GHz band, which are millimeter-wave bands, are characterized by the ability to increase throughput because a wide bandwidth can be ensured, but they are also characterized by the fact that communication is easily interrupted due to the strong directivity of radio waves. For example, Figure 1 The reference numeral 110 in indicates the communication area in the 60 GHz band. When the user having STA 102 moves from one room to another room, the communication through link 104 in the 60 GHz band may be interrupted. Figure 1 The reference numeral 100 in indicates the communication area in the 5 GHz band. The radio waves in the 5 GHz band are characterized in that they are less attenuated by moisture and obstacles than millimeter waves, they are more likely to bypass obstacles and propagate due to diffraction than millimeter waves, and they have a wider communication area than the communication area in the millimeter-wave band. Therefore, even when the user having STA 102 moves from one room to another room, communication can be stably performed.

[0042] In view of the features described above, this embodiment provides a mechanism for setting up multi-link communication such that when multi-link communication is established, it includes at least one or more links in a frequency band different from the millimeter-wave band. In other words, this embodiment provides a mechanism for suppressing the establishment of multi-link communication only in the millimeter-wave band. Now, this mechanism will be described in detail.

[0043] <Hardware Configuration of Communication Device>

[0044] Figure 2 An exemplary hardware configuration of a communication device (AP and STA) is illustrated. As an exemplary hardware configuration, the communication device includes a storage unit 201, a control unit 202, a functional unit 203, an input unit 204, an output unit 205, a communication unit 206, and antennas 207 to 209.

[0045] The storage unit 201 is composed of one or both of a ROM and a RAM. The storage unit 201 stores programs for performing various operations (described below) and also stores various types of information such as communication parameters for wireless communication. RAM is an abbreviation for Random Access Memory, and ROM is an abbreviation for Read Only Memory. In addition to memories such as ROM and RAM, storage media such as hard disks or non-volatile storage devices such as solid-state drives (SSDs) can be used as the storage unit 201.

[0046] The control unit 202 is composed of, for example, a processor such as a CPU or an MPU, an application-specific integrated circuit (ASIC), a digital signal processor (DSP), or a field-programmable gate array (FPGA). CPU is an abbreviation for Central Processing Unit, and MPU is an abbreviation for Micro Processing Unit. The control unit 202 controls the entire device by executing the programs stored in the storage unit 201 and operating hardware circuits such as ASICs. The control unit 202 can be configured to control the entire device by working together with the programs stored in the storage unit 201 and the operating system (OS).

[0047] The control unit 202 controls the functional unit 203 to perform predetermined processes such as imaging, printing, and projection. The functional unit 203 is hardware for the device to perform predetermined processes. For example, when the communication device is a camera (such as a digital still camera) or a smart phone including a camera, the functional unit 203 is an imaging unit and performs imaging processing of surrounding images through a camera unit (not shown) included in the communication device. Also, for example, when the communication device is a printer, the functional unit 203 is a printing unit and performs printing processing on a sheet such as paper based on print data obtained from the outside through wireless communication. For example, when the communication device is a projector or smart glasses, the functional unit 203 is a projection unit and performs projection processing of image data or video data obtained from the outside through wireless communication. In the case of smart glasses, the projection surface is, for example, the retina of the end user. The data processed by the functional unit 203 can be data stored in the storage unit 201 or data transmitted and received with other APs or STAs through the communication unit 206 (described below). A communication device such as AP 101 can also provide a network storage function such as network attached storage (NAS). This function is provided as a web service such as a network storage service to other communication devices. For example, a communication device such as an STA connects to the network storage service provided by, for example, APs 101 to 103 using a protocol such as SMB, FTP, or WebDAV. A communication device such as an STA uploads a file to the storage service or downloads a file from the storage device. Data communication such as upload and download is achieved by transmitting and receiving UHR PPDUs between devices.

[0048] The input unit 204 accepts various operations from the user. The output unit 205 performs various types of output to the user. The output performed by the output unit 205 includes, for example, at least one of display on the screen, audio output from the speaker, and vibration output. A single module can provide both the input unit 204 and the output unit 205, such as a touchpad.

[0049] The communication unit 206 controls wireless communication conforming to the IEEE 802.11 standard series and controls IP communication. In this embodiment, the communication unit 206 can transmit and receive UHR PPDUs, which are radio frames of the UHR standard, and PPDUs conforming to the standards before the UHR standard, in cooperation with antennas 207 to 209. Antennas 207 to 209 are antennas capable of transmitting and receiving signals in at least one of frequency bands such as the sub-GHz band, 2.4 GHz band, 5 GHz band, 6 GHz band, 7 GHz band, and 60 GHz band.

[0050] When the communication device complies with, for example, the NFC standard, Bluetooth standard, or wired communication standard described above, the communication unit 206 can be configured to control wireless communication or wired communication that complies with these communication standards. When the communication device is capable of performing wireless communication that complies with multiple communication standards, the communication device can be configured to include separate communication units and antennas corresponding to different communication standards. Antennas 207 to 209 are antennas capable of communicating in the 2.4 GHz band, 5 GHz band, 6 GHz band, 45 GHz band, and 60 GHz band. Although STA 102 includes three antennas in this embodiment, it can include two antennas or can include different antennas for each frequency band. When STA 102 includes multiple antennas, STA 102 can include a communication unit 206 corresponding to each antenna.

[0051] The antenna included in AP 101 and supporting millimeter waves is a phased array antenna in order to perform beamforming communication with a STA (such as STA102). When performing downlink communication with STA 102 through the link 104 in 60 GHz shown in Figure 1 , AP 101 adjusts the phase of the current flowing through the phased array antenna and transmits radio waves with directivity in the direction of STA 102. This process allows radio waves in the millimeter wave band, which are easily attenuated, to be efficiently transmitted to STA102. Like the AP, the STA can also use a phased array antenna as an antenna supporting millimeter waves. The STA can be configured to have multiple antennas supporting millimeter waves at multiple positions (such as on the side surface and the rear surface of the STA's housing and on the display side of the STA) in order to widen the angle at which radio waves can be transmitted and received.

[0052] Now, the functional configuration of the communication device will be described using Figure 3 Communication devices such as AP 101 and STA 102 include functional units such as a multi-link control unit 301, a multi-link communication setting UI unit 302, a frame generation unit 305, and a frame transmission and reception unit 306.

[0053] The multi-link control unit 301 is a functional block configured to control communication start processing for establishing one or more links used by the communication device in wireless communication with the other device, link addition and deletion processing after communication starts, and communication end processing for deleting all links. The connection processing includes authentication processing, association processing, and four-way handshake (4WHS) processing. The other device of AP 101 is a STA such as STA 102, and the other device of STA 102 is an AP such as AP101.

[0054] The multi-link communication setting user interface (UI) unit 302 provides a setting screen as a UI that allows a user to enter settings for multi-link communication. The UI unit 302 is a functional block that accepts user operations on the setting screen through the input unit 204 and stores the settings in the storage unit 201 as operation settings of the communication device.

[0055] The frame generation unit 305 is a block that generates a UHR PPDU as a radio frame for external communication. The frame transmission and reception unit 306 transmits the radio frame generated by the frame generation unit 305 and receives radio frames from the device at the other end. The STA 102 transmits a probe request frame, an association request frame, and a data frame to the AP. The STA 102 also transmits an authentication request frame and other frames for connection processing to the AP.

[0056] The AP 101 transmits a beacon frame, a probe response frame, an association response frame, and a data frame to the STA 102. The AP 101 also transmits an association request frame, an authentication request frame, and other frames for connection processing to the STA.

[0057] <Connection processing>

[0058] Now, the connection processing according to the first embodiment will be described using the Figure 4 flowchart in. Figure 4 The flowchart in outlines the process of the connection processing performed by the AP 101 and a STA (such as the STA 102) as the other device. Figure 4 Each step in is repeatedly executed when the AP 101 is providing the functions of the AP.

[0059] Each step shown in each flowchart is executed when the processor of the control unit 202 in the AP 101 executes a computer program stored in the storage unit 201. Some processes such as transmission and modulation are implemented when the processor of the control unit 202 works together with various processors, ASICs, DSPs, and FGPAs that make up the communication unit 206 and also with the ASICs, DSPs, and FGPAs that make up the control unit 202. When it is necessary to clarify the main body of the execution process, the process will be described with any one of the functional units shown in Figure 3 as the main body.

[0060] In S401, the AP 101 determines whether a connection request has been received from a STA (such as the STA 102). If a connection request has been received, then the AP 101 advances the process to S402, and if a connection request has not been received, then the AP 101 waits for a connection request. A connection request from a STA is, for example, an association request frame. When such a frame is received, the AP 101 determines that a connection request has been received.

[0061] In S402, the multi-link control unit 301 determines whether the STA requests a multi-link connection. Specifically, if the received connection request frame includes a multi-link element, then the control unit 301 determines that the STA requests a multi-link connection. On the other hand, if the received connection request frame does not include a multi-link element, then the control unit 301 determines that the STA does not request a multi-link connection.

[0062] The multi-link element may include information for identifying other links. Now, [description will be provided using] Figure 6 to describe the multi-link element. Figure 6 is a schematic diagram for explaining the multi-link element.

[0063] The multi-link element includes an "Element ID" 601, a "Length" 602, and an "Element ID Extension" 603. The multi-link element also includes a "Multi-link Control" 604, a "Common Information" 605, and a "Per STA Profile" 606. In this embodiment, the number of "Per STA Profile" 606 is equal to the number obtained by subtracting one from the number of links configured between the STA and the AP.

[0064] The "Element ID" 601 and the "Element ID Extension" 603 store information for identifying this element as a multi-link element. In this embodiment, the Information Element in which the "Element ID" 601 stores "255" and the "Element ID Extension" 603 stores "107" is a multi-link element. However, the present invention is not limited thereto. Hereinafter, the Information Element will be abbreviated and also simply referred to as IE.

[0065] The "Length" 602 stores the length of the entire multi-link element.

[0066] The "Multi-link Control" 604 includes a bitmap indicating what information is included in the "Common Information" field (described below) and a "Type" field indicating the type of the multi-link element. Moreover, based on the value indicated by the "Multi-link Control", it is indicated whether, for example, an MLD MAC address is included in the multi-link element.

[0067] The "Common Information" field 605 includes information common to all links. The "Per STA Profile" 606 may or may not be included in the multi-link element, depending on the type in the above-described "Multi-link Control" 604. The "Per STA Profile" 606 includes information for each link.

[0068] Details of the "per STA profile" 606 will now be described. The "per STA profile" 606 includes a "sub-element ID" 611, a "length 612", and "data" 613. The "sub-element ID" 611 is set to indicate that the "per STA profile" 606 is "1" for the "per STA profile". The length of the entire "per STA profile" is set in the "length" 612. Further details regarding each link are set in the "data" 613.

[0069] The "data" 613 includes a "STA control" field 621, "STA information" 622, "capability information" 623, and "element 1" 624-1 to "element N" 624-N. The "data" 613 also includes a Non-Inferitance element 625.

[0070] The "STA control" field 621 includes a "link ID" 631, a "complete profile" 632, a "MAC address presence" 633, and other fields. The "link ID" 631 indicates the link ID. For example, in this embodiment, the "link ID" 631 stores 1 when indicating link 103 in Figure 1 and stores 2 when indicating link 104 in Figure 1

[0071] The "complete profile" 632 stores a flag indicating whether to provide the entire information about the link. For example, when the ML probe request transmitted by STA102 specifies a request for the entire information about the link to the AP, the AP 101 sets the "complete profile" 632 to 1. The AP 101 then includes in the fields following 622 the details unique to each link included in the beacon etc. transmitted over the link.

[0072] When the "complete profile" 632 is set to 0, the communication device may omit some or all of the information stored in the "element 1" to "element N".

[0073] The "MAC address presence" 633 stores information indicating whether to include information indicating the MAC address. The other fields following 633 are fields indicating whether to include other individual information (such as beacon interval information). That is, the field 621 indicates the type of data stored in the "STA information" 622 and thereafter.

[0074] In this embodiment, when transmitting a probe request / response, the AP 101 and the STA 102 transmit a MAC frame including a multi-link element in which the "complete profile" 632 is set to 0.

[0075] When transmitting an ML probe response, the AP 101 transmits a MAC frame including a multi-link element in which the "complete profile" 632 is set to 1.

[0076] The ML probe request / response is a MAC frame that is transmitted to obtain information about APs / STAs in other frequency bands operating in a multi-link. Note that instead of the "complete profile" 632, the ML probe request stores a "complete profile request" indicating that detailed information is to be requested. Details will be described later.

[0077] "Element 1" 624-1 to "Element N" 624-N store element information unique to each link.

[0078] Examples of 624-1 to 624-N will now be described. Assume that a communication device supporting operation in both the millimeter-wave band and the 5 GHz band includes a multi-link element in a MAC frame transmitted in the 5 GHz band. For example, the communication device may include information about the millimeter wave and information about other links in 624-1 to 624-N for 5 GHz. Here, for example, an antenna sector ID pattern element indicating the result of beamforming performed using the millimeter wave may be stored in one of 624-1 to 624-N. An antenna sector ID pattern element indicating the sector number selected in the SLS may be stored in one of 624-1 to 624-N. Note that the SLS will be described later. The sector number is the result obtained by beamforming performed using the millimeter wave. "Element 1" to "Element N" indicating individual information about each link may include various other information.

[0079] STA 102 receives from the AP an ML probe response including a multi-link element in which information about each link provided by the AP is stored in the "per STA profile" field 606. This process allows STA 102 to obtain information about each link provided by the AP.

[0080] Referring again to Figure 4 , although in S402 an example is described of determining whether a multi-link element has been added to a radio frame of a connection request, the configuration is not limited thereto. The AP 101 may be configured to determine a request for a multi-link connection when a multi-link element has been added and includes information about other links. The radio frame of the connection request is an association request frame or a re-association request frame. This frame includes a link ID as information for identifying a link, and the AP 101 can identify the operating frequency band and channel of the corresponding link from the link ID. That is, the AP 101 can identify the operating frequency band in which the link of the connection request is operating.

[0081] First, the case where a multi-link connection has not been determined to be requested will be described. In S405, the AP 101 performs connection processing using the link on the wireless communication channel through which the connection request has been received. When the connection processing is completed, application data (such as video, moving images, and sound) can be transmitted between the AP 101 and the STA (such as STA 102) that has transmitted the connection request. If an error occurs during a series of connection processing, the AP 101 notifies the STA of information indicating the nature of the error.

[0082] The AP 101 can be configured such that if the wireless communication channel on which the connection request has been received is a wireless communication channel in the millimeter-wave band, the AP 101 can reject a connection request on only the millimeter-wave channel.

[0083] The PPDU in the millimeter-wave band conforming to the UHR standard and the PPDU in the millimeter-wave band conforming to the 802.11ay standard established in 2021 can have different formats. In view of this situation, the AP 101 can be configured to allow a connection request only when it is determined that the format of the connection request frame conforms to the 802.11ay format assuming single communication using millimeter waves. That is, when a connection request conforming to 802.11ay is received, a link in a single millimeter-wave band can be established.

[0084] In this case, the AP 101 can reject a connection request that has been transmitted in a PPDU conforming to the UHR format that allows multi-link communication and attempts to establish a single connection using only millimeter waves.

[0085] Next, the processing performed when the control unit 301 determines that multi-link communication has been requested will be described. In S403, the control unit 301 determines whether the frequency band in which the connection request has been received is the millimeter-wave frequency band. If it is determined that the frequency band in which the connection request has been received is the millimeter-wave frequency band such as the 45 GHz band or the 60 GHz band, the control unit 301 advances the processing to S404. On the other hand, if it is determined that the frequency band in which the connection request has been received is not the millimeter-wave frequency band such as the 45 GHz band or the 60 GHz band (that is, if it is determined that the frequency band is a low-frequency band), the control unit 301 advances the processing to S407.

[0086] In S404, the control unit 301 determines whether the other link to be connected indicated by the connection request includes a link operating in a frequency band different from the millimeter wave band (i.e., the low frequency band). If it is determined that the other link to be connected includes a link operating in a frequency band different from the millimeter wave band (i.e., the low frequency band), the control unit 301 advances the process to S407. On the other hand, if it is determined that the other link to be connected does not include a link operating in a frequency band different from the millimeter wave band (i.e., the low frequency band), the control unit 301 advances the process to S406. The link not operating in the low frequency band means that all the links to be connected indicated by the connection request operate in the millimeter wave band.

[0087] In S406, the control unit 301 transmits a response indicating that the connection is rejected to the STA that has transmitted the connection request.

[0088] In S407, the control unit 301 performs connection processing for multi-link communication. When the connection processing is completed, a series of processes ends. The details of the connection processing will be described later using Figure 5 the sequence diagram in

[0089] This embodiment assumes that when rejecting a connection, the AP 101 responds with an association response frame in which a status code indicating rejection is set, as a response to the association request frame. However, the response is not limited to this. The AP 101 may return a rejection status code in a certain radio frame. To reject a connection retry from the STA 102, the AP 101 may notify the STA 102 of a probe response including connection rejection for a certain period of time, as a response to the probe request transmitted from the STA 102. The ML probe response as a response to the ML probe request may include information the same as or similar to the information described above. This can be done by further adding an IE such as MBO-OCE defined by the Wi-Fi (registered trademark) Alliance to a response frame such as the probe response. By including an attribute such as "association not allowed indication" in the IE, the AP 101 can notify the STA 102 of the connection rejection. MBO-OCE is an abbreviation for Multiband Operations-Optimized Connectivity information element.

[0090] Now, the configuration of MBO-OCE will be described in detail using Figure 8 the following. Figure 8It is a schematic diagram for explaining MBO-OCE. The MBO-OCE IE includes "Element ID" 801, "Length" 802, "OUI" 803, "OUI Type" 804, and "MBO Attribute" 805. MBO-OCE is an IE in which "0xDD" is set for "Element ID" 801, "0x50-6F-9A" is set for "OUI" 803, and "0x16" is set for "OUI Type".

[0091] "0xDD" of the "Element ID" indicates vendor-specific information in IEEE 802.11. "0x50-6F-9A" of the "OUI" indicates that this IE is related to the Wi-Fi Alliance. OUI is the abbreviation of Organizationally Unique Identifier, and "0x50-6F-9A" indicates the vendor ID assigned by the Wi-Fi Alliance. The type information for identifying further details is stored in the "OUI Type", and "0x16" indicates that this element is the MBO-OCE IE.

[0092] "Length" 802 indicates the length of the entire IE. "MBO Attribute" 805 includes "Attribute ID" 811, "Attribute Length" 812, and "Reason Code" 813. In this embodiment, the AP 101 sets "0x04" for the "MBO Attribute" 805. "0x04" indicates that the attribute is the "Association Not Allowed" attribute. This attribute indicates that the connection will be rejected. "Attribute Length" 812 indicates the length of the attribute. The subsequent "Reacon Code" 813 stores the information indicating the reason for not allowing the connection. In this embodiment, for example, 0x01 can indicate an unspecified reason.

[0093] Now it will use Figure 5 The sequence diagram in Figure 5 to describe each step of the communication including the processes before and after connection handling.

[0094] The AP 101 can operate an affiliated AP on each of three or more channels including at least one or more millimeter-wave bands and one or more low-frequency bands. For explanation, Figure 5 illustrates an example in which the AP 101 operates an affiliated AP belonging to the AP MLD on a channel in the 60GHz band and a channel in the 5GHz band.

[0095] The AP 101 transmits beacons (S5011 and S5012) in the 60GHz band which is a millimeter-wave band and the 5GHz band which is a low-frequency band.

[0096] STA 102 also transmits a DMG beacon in the 60 GHz band (S5011). DMG is an abbreviation for Directional MultiGigabit.

[0097] Based on the transmission and reception of the DMG beacon, AP 101 and STA 102 perform sector-level sweeping (SLS) in the 60 GHz band (S5021). By performing SLS, AP 101 and STA 102 estimate their relative positions. Based on the estimated values, AP 101 and STA 102 each set the antenna directivity in the direction of the other device and transmit a probe request and a probe response in the 60 GHz band (S5031 and S5041).

[0098] STA 102 and AP 101 also transmit a probe request and a probe response in the 5 GHz band (S5032 and S5042).

[0099] Due to space limitations, the following description illustrates an example of the setting process for performing multi-link communication on the operating channel in the 5 GHz band. However, the present invention is not limited thereto. If STA 102 discovers the opposite AP 101 on the operating channel in the 60 GHz band, then the setting process for multi-link communication can be performed on the operating channel in the 60 GHz band.

[0100] Next, STA 102 and AP 101 transmit an ML probe request (S5052) and an ML probe response (S5062) to obtain information about each link. The ML probe request includes a probe request multi-link element. In S5052 and S5062, frames are exchanged to obtain detailed link information that cannot be obtained from the probe response. For example, if this connection is not the first connection and parameters have been exchanged during a previous connection, then the frame exchange in S5052 and S5062 can be skipped. Here, STA 102 and AP 101 transmit an ML probe request (S5052) including a multi-link element and an ML probe response (S5062) including a multi-link element.

[0101] STA 102 includes a probe request multi-link element in the ML probe request, and the probe request multi-link element is a multi-link element of a type different from the Figure 6 multi-link element shown in Figure 9 . Now, the probe request multi-link element will be described using Figure 6 . The description of configurations that are the same as or similar to the configuration shown in Figure 6It differs in that it includes a "Full Profile Request" 932 that requests a full profile, rather than a "Full Profile" 632, and omits the field corresponding to 633. By setting the "Full Profile Request" 932 to "1", the STA 102 indicates that it wants to request detailed information about the attached AP.

[0102] In response to the ML Probe Request, the AP 101 sets the "Full Profile" of the multi-link element to 1 and transmits an ML Probe Response that stores detailed information about each link to the STA 102. In Figure 5 In the example shown in, the AP 101 transmits a response in S6062 that includes detailed information about the attached AP operating in the 60 GHz band. If the AP 101 is operating an attached AP in other operating frequency bands, the AP 101 transmits an ML Probe Response that further includes detailed information about these attached APs.

[0103] The multi-link element can be included in the probe requests, probe responses, and beacons described above. When the multi-link element is included in the probe requests and probe responses described above, communication devices such as APs and STAs set the "Full Profile" to 0. In this case, some information is omitted compared to when the "Full Profile" is set to 1. This enables information indicating, for example, that multi-link communication is possible to be notified to the STA 102 without significantly increasing the size of the data to be included in the beacon or response. Beacons and probe requests / responses are used in the preliminary scanning process. Therefore, it is possible to notify the other device in the preliminary scanning stage whether multi-link communication is possible, for example.

[0104] Next, the AP 101 and the STA 102 perform each step of authentication to perform authentication between the AP 101 and the STA 102 (S5072).

[0105] Next, the STA 102 transmits an association request as a connection request to the AP (S5082). The connection request transmitted here can be a re-association request.

[0106] The STA 102 includes information in the association request that identifies the link to be connected through which multi-link communication is to be established. In this embodiment, by using the multi-link element described with reference to Figure 6 The STA 102 notifies the AP of the link ID of the link for which connection is requested. More specifically, by storing multiple link IDs of the link to be connected in the "Per STA Profile" of the multi-link element, the STA102 indicates the link for which connection establishment is requested.

[0107] Upon receiving the association request, the AP 101 responds with an association response (S5092).

[0108] AP 101 can accept the setup process of multi-link communication on a radio channel in a millimeter-wave band (such as the 60 GHz band). In this case, an association request as an authentication request is transmitted on the radio channel in the millimeter-wave band. Here, AP 101 determines a reference Figure 4 whether the link to be connected described is only a link in the millimeter-wave band. This process can prevent multi-link configuration only in the millimeter-wave band.

[0109] Next, AP 101 and STA 102 perform a communication parameter determination process (S510). For example, based on pre-stored connection information, STA 102 performs a 4-way handshake to generate a key for encrypted communication, and determines the operating frequency band, radio channel, and bandwidth of each link used in the communication with AP 101. The communication parameter determination process may include a communication parameter sharing process using a protocol for parameter exchange (such as Wi-Fi Sinple Config (WSC) or Device Provisioning Protocol (DPP)). The communication parameter determination process may include an encryption key sharing process between the AP and the STA based on Opportunistic Wireless Encryption (OWE).

[0110] When the authentication and the parameter determination process including key exchange for encryption and determination of the operating frequency used in each link are completed, STA 102 and AP 101 become ready to transmit data frames.

[0111] When ready to transmit data frames, AP 101 and STA 102 transmit application data such as video, moving images, and sound (S5111, S5121, S5112, and S5122). Through the process described above, a connection for multi-link communication can be established between AP 101 and STA 102.

[0112] As described above, when receiving a connection request for a multi-link connection from STA 102, AP 101 can prevent a multi-link connection configured only by links in the millimeter-wave band. Therefore, in a multi-link connection, a link in the low-frequency band is always included and this can improve the reliability of communication between the AP and the STA. If it is determined that the frame format of a connection request for a single connection that is not a multi-link conforms to the IEEE 802.11ay format assuming single communication using millimeter waves, then a connection through one link in the millimeter-wave band can be permitted. Therefore, it is possible to connect STAs and APs that support the existing millimeter-wave band in, for example, IEEE 802.11ay but do not support multi-link communication without any problems.

[0113] <Second Embodiment>

[0114] In the first embodiment, an example in which the AP 101 determines whether to permit a connection has been described. In the second embodiment, a mechanism in which, based on the link information received by the STA 102, the link used in multi-link communication always includes a link in the low frequency band will be described.

[0115] For example, the hardware configuration and functional configuration of the communication device according to the second embodiment and the process of using Figure 5 the multi-link connection described are the same as or similar to those in the first embodiment. Descriptions of the processing that is the same as or similar to that in the first embodiment will now be omitted where appropriate.

[0116] The second embodiment is different from the first embodiment in that a restriction is imposed when the STA 102 selects a link to be used in multi-link communication. The connection processing according to the second embodiment will now be described in detail using Figure 7 the flowchart in. Figure 7 The flowchart in outlines the process of the connection processing performed by the STA 102 and an AP (such as the AP 101) as the other device. Figure 4 The steps in are executed when a connection to the AP is necessary (such as when the wireless communication function of the STA 102 changes from the disabled state to the enabled state, or when the connection to the currently connected AP is interrupted and another AP is searched for again).

[0117] Each step shown in the flowchart is executed when a processor of the control unit 202 in the STA 102 executes a computer program stored in the storage unit 201. Some processes such as transmission and modulation are implemented when the processor of the control unit 202 works together with various processors, ASICs, DSPs, and FGPAs that make up the communication unit 206 and also with the ASICs, DSPs, and FGPAs that make up the control unit 202. When it is necessary to clarify the main body of the execution processing, the processing will be described with any one of the functional units shown in Figure 3 as the main body.

[0118] In S700, the STA 102 performs a scanning process of searching for an AP in the low frequency band. There are two types of scanning processes: active scanning and passive scanning. This embodiment assumes that both types of scanning processes are performed. In active scanning, the STA102 transmits a probe request and receives a probe response as a response thereto in order to confirm the presence of an AP in the vicinity.

[0119] In passive scanning, the STA 102 receives a beacon or a FILS discovery frame transmitted by a neighboring AP in order to confirm the presence of an AP in the vicinity. FILS is an abbreviation for Fast Initial Link Set up.

[0120] Another technique for passive scanning is to perform processing such as listening for probe responses transmitted by neighboring APs to another STA. STA 102 confirms the presence of neighboring APs by performing these two types of scanning processes at regular intervals (such as every 100 ms) on the channels in the 2.4 GHz band and 5 GHz band supported by STA 102. Moreover, STA 102 confirms the presence of neighboring APs operating in the 6 GHz band by performing these two types of scanning processes at regular intervals (such as every 100 ms) on the preferred scanning channels defined by 6 GHz.

[0121] STA 102 generates a list that lists the APs whose presence has been confirmed by scanning as connection candidates. This list stores information indicating whether the information obtained from the AP includes multi-link elements and information about its content.

[0122] In S701, STA 102 determines whether a connection destination has been identified from the list of connection destination candidates obtained as a result of scanning. Specifically, if an AP whose connection history is managed by the OS of STA 102 (i.e., an AP to which STA 102 has been connected in the past) is found on the list, then that AP is identified as the connection destination. The output unit 205 may be configured to display a list of connection destination candidates (not shown) to accept user operations on the list such that the connection destination is identified.

[0123] The list of connection candidates also lists APs other than those that can receive beacons or probe responses through the scanning process. The list of connection candidates may list APs included in the multi-BSSID element added to the beacon or probe response, or APs based on the BSSID included in the reduced neighbor report element. BSSID is an abbreviation for Basic Service Set Identifie. Hereinafter, the reduced neighbor report element may be abbreviated as the RNR element.

[0124] The list of connection candidates may list information about AP MLDs identified based on the AP MLD ID included in the multi-link element, or may list the AP information received in the FILS discovery frame. Regarding an AP whose information has been received indirectly from a neighboring AP, a determination as to whether to list the AP as a connection candidate may be made after confirming the presence of the AP. Specifically, an AP can be added to the list of connection candidates only when the presence of the AP is confirmed again by scanning on the channel, or only when a probe request specifying the SSID of the AP is transmitted and a response is received. SSID is an abbreviation for Service SetIdentifier (service set identifier).

[0125] In S702, the STA 102 determines whether the identified connection destination is an MLD AP. Specifically, the STA 102 refers to the list of connection candidates and determines whether the multi-link element is included in the information obtained from the identified connection destination AP. Next, if it is determined that the multi-link element is included, then the STA 102 determines that the identified connection destination is an AP MLD and advances the process to S703. On the other hand, if it is determined that the multi-link element is not included, then the STA 102 determines that the identified connection destination is not an AP MLD and advances the process to S706.

[0126] In S703, the control unit 301 of the STA 102 selects the link to be used in the multi-link communication with the identified connection destination and performs the connection process. Specifically, the control unit 301 of the STA 102 transmits the ML probe request described in S5052 to the identified connection destination, receives the ML probe response, and obtains the detailed information about the other links that can be used in the multi-link communication. The control unit 301 of the STA 102 also obtains the information about the RNR element included in the ML probe response, for example.

[0127] In the RNR element transmitted by the AP MLD, the information about one or more attached APs corresponding to the AP MLD and the information about the neighboring APs are listed. This information includes the information about the operating frequency band of the attached AP and the information about the radio channel. Other information such as the identification information about the SSID may also be included.

[0128] In order to distinguish the neighboring APs from the attached APs that can be selected as the links for the multi-link communication, the MLD ID is associated with the information about the attached APs. The link with the MLD ID specified as 0 indicates the other links that can be used in the multi-link communication.

[0129] Based on the obtained information, the STA 102 generates a list associating the link ID, the operating frequency band, and the radio channel of the attached APs to be provided to the AP MLD that is the identified connection destination. This list will be described using Table 1. Here, as an example, the list generated when the AP MLD that is the identified connection destination supports five frequency bands is illustrated.

[0130] [Table 1]

[0131] Link ID Operating frequency band Channel 1 2.4 GHz 6ch 2 5 GHz 36ch 3 6 GHz 15ch 4 45 GHz 2ch 5 60 GHz 1ch

[0132] The control unit 301 selects two or more links as candidate connection links based on, for example, the channel on which the ML detection request has been transmitted, information about the frequency band supported by the control unit 301 and allowing the STA to operate, and hardware constraints such as the number of antennas. The STA 102 includes one or more links corresponding to the low frequency band among the candidate connection links. That is, in the present embodiment, control is performed so as not to perform multi-link connection processing for the combination of link IDs "4" and "5".

[0133] After the selection of the candidate connection links is completed, multi-link setting processing is attempted. Specifically, the control unit 301 performs Figure 5 the authentication processing shown in. The control unit 301 then transmits an association request including a multi-link element in which information indicating the link IDs corresponding to the selected candidate connections is stored. Then, Figure 5 the connection processing shown in is performed. The link IDs stored in the multi-link element included in the association request are used as information for identifying the links through which the connection is to be established. When the STA 102 can establish one link in the low frequency band and one link in the millimeter wave band, the STA 102 selects a plurality of links having a combination of the low frequency band and the millimeter wave band as candidate connection links.

[0134] In S704, the control unit 301 determines whether the connection has been successful. If a series of connection processing is completed and the connection is successful, then the control unit 301 ends the series of connection processing. If an error occurs in any step of the series of connection processing, then the control unit 301 determines that the connection is not successful and advances the processing to S705. In S705, the determination unit 301 determines whether another combination can be selected, and if it is determined that another combination can be selected, then the determination unit 301 advances the processing to S703 and retries the multi-link connection processing using that combination. For example, the determination unit 301 selects a combination of low frequency bands such as the 2.4 GHz and 5 GHz bands as candidate connection links and retries the connection processing. On the other hand, the determination unit 301 determines whether another combination can be selected, and if it is determined that another combination cannot be selected, then the determination unit 301 advances the processing to S706.

[0135] In S706, the STA 102 performs single-link connection processing in any frequency band classified as the low frequency band. In S707, the STA 102 determines whether the connection has been successful. If the connection has been successful, then the STA 102 ends the series of processing, while if the connection has failed, then the STA 102 advances the processing to S708. If it is determined in S702 that the identified connection destination is not the AP MLD, then the STA 102 may perform single-link connection processing on the channel of the identified connection destination.

[0136] The processing to be executed when STA 102 cannot connect to the AP during the scan in the low frequency band will be described in S708 and its subsequent steps.

[0137] In S708 and S709, STA 102 performs a scan in the millimeter wave frequency band and processing for identifying a connection destination. The description of this processing is omitted because it is the same as or similar to the processing in S701 and S702. In this processing, a list of APs discovered by the scan in the millimeter wave frequency band and neighboring APs obtained from the discovered APs is generated, and a connection destination is appropriately identified from this list. If no connection destination is identified, then STA 102 advances the processing to S700 and executes a scan process to search for other connection candidates.

[0138] In S710, the control unit 301 determines whether the identified connection destination is the AP MLD. The processing executed here is the same as or similar to the processing in S702. If it is determined that the identified connection destination is the AP MLD, then the control unit 301 advances the processing to S711, while if it is determined that the identified connection destination is not the AP MLD, then the control unit 301 advances the processing to S712.

[0139] In S711, STA 102 performs a single-link connection process for the channel of the identified connection destination. For example, a connection candidate that is not the AP MLD discovered by using millimeter wave scanning is expected to be an AP compliant with IEEE 802.11ay. Therefore, STA 102 only needs to perform a single-link connection according to the connection process of IEEE 802.11ay.

[0140] In S712, the control unit 301 determines whether the connection candidate link includes a link in the low frequency band. If it is determined that the connection candidate link includes a link in the low frequency band, then the control unit 301 advances the processing to S713. On the other hand, if it is determined that the connection candidate link does not include a link in the low frequency band, then the control unit 301 does not connect to the identified connection destination and executes a scan process for other connection candidate APs. This processing of not connecting to the identified connection destination means that when the connection candidate link of the connection candidate AP is only a link in the millimeter wave frequency band, the control unit 301 controls STA 102 not to transmit a connection request to this AP.

[0141] Further details of the determination process will now be described. By using the ML probe request / response and RNR elements described in S703, the control unit 301 generates a list associating the link ID, operating frequency band, and radio channel provided by the AP MLD that will be the connection destination. If a link in the low-frequency band is on the list, the control unit 301 determines that the connection candidate links include the link in the low-frequency band. If a link in the low-frequency band is not on the list, the control unit 301 determines that the connection candidate links do not include the link in the low-frequency band. For example, when generating the list of connection candidates shown in Table 1, the control unit 301 advances the process to S713.

[0142] In S713, the control unit 301 selects two or more links that always include the low-frequency band and performs connection processing for multi-link communication. Specifically, the control unit 301 transmits an association request including a multi-link element in which information indicating the link ID corresponding to the selected connection candidate is stored. This is followed by the Figure 5 connection processing shown in. In the selection of connection candidate links, STA 102 gives priority to selecting a plurality of links that combine the low-frequency band and the millimeter-wave band.

[0143] In S714, STA 102 determines whether the connection has been successful. If the connection has failed, then STA 102 scans for additional connection candidates, and if the connection has been successful, then STA 102 ends the series of connection processing.

[0144] Through the processing described above, when STA 102 performs multi-link communication with AP 101 including a link in the millimeter-wave band, STA 102 can transmit a connection request in a form that always includes a link in the low-frequency band.

[0145] In this embodiment, an example has been described in which the scanning of connection candidates in the low-frequency band is followed by the scanning of connection candidates in the millimeter-wave band. However, the present invention is not limited to this. The scanning in the low-frequency band can be performed simultaneously with the scanning of connection candidates in the millimeter-wave band. By accepting a user operation on the scanning setting screen (not shown) provided to the communication setting UI unit 302, the frequency band in which the scanning is to be performed can be determined.

[0146] <Third Embodiment>

[0147] In the first and second embodiments, examples in which connection requests in the millimeter wave band can be accepted have been described. In the third embodiment, a mechanism configured to receive connection requests including the low frequency band under more simplified control will be described. Specifically, the mechanism is configured not to allow connection requests in the millimeter wave band and to accept connection requests only in frequency bands classified as the low frequency band. This embodiment focuses on the fact that multi-link communication can be set in such a way that the link through which the connection request is transmitted is the primary link of the multi-link communication.

[0148] The processing will now be described in detail using Figure 10 Sequence diagrams. Figure 10 FIG. is a sequence diagram for explaining the third embodiment. Figure 10 Corresponding to the Figure 5 sequence diagram described in the first embodiment, and the same or similar processing will be denoted by the same reference numerals.

[0149] Differences from Figure 5 are that an MBO-OCE including an "association not allowed indication" attribute is added to the DMG beacon and probe response transmitted by the AP 101 in the millimeter wave band. Specifically, the AP 101 includes an MBO-OCE including an "association not allowed indication" attribute in the DMG beacon to be transmitted to the STA, and transmits the DMG beacon to the STA (S10011). Further, the AP 101 includes an MBO-OCE including an "association not allowed indication" attribute in the probe response to be transmitted in the millimeter wave band, and transmits the probe response (S10041). The AP 101 also includes an MBO-OCE including an "association not allowed indication" attribute in the ML probe response to be transmitted in the millimeter wave band.

[0150] The above-described processing allows the AP 101 to notify the STA (such as the STA 102) in advance that connection requests cannot be made in the millimeter wave band. At the same time, the AP 101 performs control to appropriately transmit, for example, the DMG beacon. Therefore, as in the first embodiment, for example, the antenna pointing angle can be set in advance in the SLS phase.

[0151] When an association request is received from the STA through a channel in the millimeter wave band, the AP 101 responds with an association response frame in which a status code indicating rejection is set (S10081, S10091). This processing makes it possible to prohibit the setting process of multi-link communication in the millimeter wave band.

[0152] Finally, the STA 102 of the third embodiment transmits a connection request for setting multi-link communication through a channel in a frequency band classified as a low-frequency band. In this case, the STA 102 transmits the connection request to the AP 101 through an antenna for communicating at 2.4 GHz or 5 GHz. In the selection of connection candidate links, the STA 102 gives priority to selecting a plurality of links that combine the low-frequency band and the millimeter-wave band.

[0153] As described above, in the third embodiment, it is possible to disallow a connection request in the millimeter-wave band and accept a connection request only in a frequency band classified as a low-frequency band. Therefore, multi-link communication in which the low-frequency band is always included as the primary link is set.

[0154] <Modification>

[0155] In the third embodiment, a mechanism has been described in which when performing multi-link communication using a communication link in the millimeter-wave band, a communication link in a frequency band different from the millimeter-wave band is established in addition to the communication link in the millimeter-wave band. On the other hand, depending on how the user uses the STA 102, there may be a case where it is not desired to establish multi-link communication using millimeter waves. In view of this, an operation setting for whether to establish multi-link communication including millimeter waves can be set through a setting screen. In this case, the setting UI unit 302 of the STA 102 displays a communication setting screen (not shown) for accepting an operation setting for whether to establish multi-link communication including millimeter waves. By operating the communication setting screen, the user who owns the STA 102 gives an instruction to change the operation setting. When accepting the change instruction, the setting UI unit 302 changes the operation setting to be stored in the storage unit 201 based on the change instruction.

[0156] When the operation setting for establishing multi-link communication including millimeter waves is stored, the STA 102 performs a connection process that is the same as or similar to the connection process in the third embodiment. On the other hand, when the operation setting for not establishing multi-link communication including millimeter waves is stored, the STA 102 selects only a link classified as a link in the low-frequency band as the link used in multi-link communication. With the above-described modification, it is possible to flexibly control the establishment of a connection in consideration of, for example, a user who does not wish to establish multi-link communication in the millimeter-wave band.

[0157] (Other Embodiments)

[0158] The present invention can also be implemented by a program that executes one or more functions described above being supplied to a system or device via a network or a storage medium and one or more processors in a computer of the system or device reading and executing the program. The present invention can also be implemented by a circuit (e.g., ASIC) that executes one or more functions.

[0159] The present invention is not limited to the embodiments described above, and various changes and modifications can be made thereto without departing from the spirit and scope of the present invention. The appended claims are attached to disclose the scope of the present invention.

[0160] This application claims priority based on Japanese Patent Application No. 2022-182934 filed on November 15, 2022, the entire contents of which are hereby incorporated herein by reference.

Claims

1. A communication device, comprising: A control component, which is configured to establish a link on multiple different frequency channels with another communication device based on a connection request received from the other communication device. Wherein, when the link to be established identified at least based on the information included in the connection request is only a link on a frequency channel in the millimeter-wave band, the control component does not establish a link on multiple different frequency channels based on the connection request.

2. The communication device according to claim 1, wherein, When the link to be established is only a link on a frequency channel in the millimeter-wave band, the control component transmits a response indicating rejection of the connection request.

3. The communication device according to claim 1 or claim 2, further comprising: A first antenna, which is used for communication in the millimeter-wave band; And A second antenna, which is used for communication in a frequency band different from the millimeter-wave band.

4. The communication device according to claim 3, wherein, The first antenna is a phased array antenna.

5. The communication device according to any one of claims 1 to 4, wherein When a connection request conforming to IEEE802.11ay is received from another communication device, the control component performs control to establish a single link with the other communication device based on the connection request.

6. A communication device, comprising: An acquisition component, which is configured to acquire information about the frequency channels of a communication link provided by another communication device; And A control component, which is configured to transmit a connection request for establishing multiple links with the other communication device, Wherein, when a link on a frequency channel in the millimeter-wave band is included in the multiple links to be established with the other communication device, the control component transmits a connection request in which the multiple links at least include links on frequency channels in a frequency band different from the millimeter-wave band.

7. The communication device according to any one of claims 1 to 6, wherein, The frequency band different from the millimeter-wave band is a frequency band below 10 GHz.

8. The communication device according to any one of claims 1 to 7, wherein, The frequency band different from the millimeter-wave band at least includes the 5 GHz band.

9. The communication device according to claim 6, further comprising: A first antenna, which is used for communication in the millimeter-wave band; And A second antenna, which is used for communication in a frequency band different from the millimeter-wave band.

10. The communication device according to claim 9, wherein, The connection request is transmitted to the outside through the second antenna.

11. A control method for a communication device, the control method comprising: A control step of establishing a link on multiple different frequency channels with another communication device based on a connection request received from the other communication device, Wherein, when the link to be established identified at least based on the information included in the connection request is only a link on a frequency channel in the millimeter-wave band, the control step performs control not to establish a link on multiple different frequency channels based on the connection request.

12. A control method for a communication device, the control method comprising: An acquisition step of acquiring information about the frequency channels of a communication link provided by another communication device; And A control step of transmitting a connection request for establishing multiple links with the other communication device. Wherein, when a link on a frequency channel in a millimeter wave band is included in a plurality of links to be established with the other communication device, the control step transmits a connection request in which the plurality of links include at least a link on a frequency channel in a frequency band different from the millimeter wave band.

13. A program that causes a computer to execute the control method of the communication device according to claim 11 or 12.

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