Radio frame transmission method and apparatus, and radio frame reception method and apparatus

Abstract

To provide a radio frame transmission method and an apparatus, and provide a radio frame reception method and an apparatus.SOLUTION: First information for identifying a first MLD in an MLE is contained in a radio frame, and thus, and the information on the first MLD is acquired from the MLE on the basis of the first information after a receiver of the radio frame receives the radio frame. In a method, a first AP generates the radio frame containing the MLE, the MLE transports information of the first MLD, the MLE contains the first information, the first information identifies the first MLD, and the first AP transmits the radio frame. The present application is applied to a next generation Wi-Fi protocol of an IEEE802.ax, e.g., a radio local area network system for supporting 802.11be (or called as EHT protocol) and the other protocol of 802.11 family.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to Chinese Patent Application No. 202111116089.4, entitled “RADIO FRAME SENDING METHOD AND APPARATUS, AND RADIO FRAME RECEIVING METHOD AND APPARATUS,” filed with the State Intellectual Property Office of the People's Republic of China on September 23, 2021, the entire contents of which are incorporated by reference.

[0002] [Technical field] The present application relates to the field of wireless technology, and in particular to a method and apparatus for transmitting wireless frames and a method and apparatus for receiving wireless frames. [Background technology]

[0003] With the development of wireless technology, more and more wireless devices support multi-link communication. For example, the devices support simultaneous communication in the 2.4 gigahertz (GHz), 5 GHz, and 6 GHz frequency bands, or support communication on different channels of the same frequency band. This improves the communication speed between the devices. Such devices are generally called multi-link devices (MLD). A multi-link device may be a multi-link access point device or a multi-link station device.

[0004] Currently, during communication between multi-link devices, one multi-link device may transmit a radio frame containing a multi-link element (MLE) to another multi-link device. For example, the transmitter of the radio frame is an access point (AP) in a multi-link access point device. The AP may feed back a probe response frame in response to a probe request frame of a station (STA). By default, the MLE included in the probe response frame corresponds to the multi-link access point device to which the AP that transmits the probe response frame belongs, meaning that the information carried in the MLE is the station information of the multi-link access point device to which the AP that transmits the probe response frame belongs.

[0005] However, since the AP only feeds back information of the MLD where the AP is located in the wireless frame, the communication efficiency is low. When the AP needs to feed back information of other MLDs in the wireless frame, for example, when the probe request frame of the STA requests information of the MLD including the AP corresponding to the nontransmitted basic service set identifier (nontransmitted BSSID) on the link where the AP is located, how the AP feeds back the wireless frame is a technical problem that needs to be urgently solved. Summary of the Invention

[0006] This application provides a radio frame transmitting method and device, and a radio frame receiving method and device, in which first information for identifying a first MLD in an MLE is included in the radio frame, so that a receiver of the radio frame obtains the information of the first MLD from the MLE based on the first information after receiving the radio frame.

[0007] A first aspect of this application provides a wireless frame transmission method applied to WLAN communication. The method is executed by a first access point (AP), or the method is executed by a component (e.g., a processor, a chip, or a chip system) of the first AP. In the first aspect and a possible implementation manner of the first aspect, an example in which the method is executed by the first AP is used for explanation. In the method, the first AP generates a wireless frame including an MLE, the MLE carries information of a first MLD, the MLE includes first information, the first information identifies the first MLD, and the first AP transmits the wireless frame.

[0008] Based on the above technical solution, in a WLAN communication process, a wireless frame transmitted by a first AP includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Thus, after receiving the wireless frame, the receiver of the wireless frame may obtain the information of the first MLD from the MLE based on the first information. In other words, after receiving the wireless frame, the receiver of the wireless frame may determine that the MLE corresponds to the first MLD based on the first information. Thus, the receiver of the wireless frame may obtain information of stations on multiple links where the first MLD is located based on the MLE, so that the receiver of the wireless frame communicates with the first MLD.

[0009] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency.

[0010] A second aspect of the embodiment of this application provides a wireless frame receiving method applied to WLAN communication. The method is executed by a station (STA), or the method is executed by a component of the STA (e.g., a processor, a chip, or a chip system). In the second aspect and a possible implementation manner of the second aspect, an example in which the method is executed by the STA is used for explanation. In the method, the STA receives a wireless frame from a first access point AP, the wireless frame includes a multilink element MLE, the MLE carries information of a first multilink device MLD, the MLE includes first information, the first information identifies the first MLD, and the STA obtains the information of the first MLD from the MLE based on the first information.

[0011] Based on the above technical solution, in a WLAN communication process, a STA functions as a receiver of a wireless frame. A wireless frame received by a STA from a first AP includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Thus, after receiving the wireless frame, the receiver of the wireless frame may obtain the information of the first MLD from the MLE based on the first information. In other words, after receiving the wireless frame, the receiver of the wireless frame may determine that the MLE corresponds to the first MLD based on the first information. Thus, the receiver of the wireless frame may obtain information of stations on multiple links where the first MLD is located based on the MLE, so that the receiver of the wireless frame communicates with the first MLD.

[0012] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency.

[0013] A third aspect of an embodiment of this application provides a radio frame transmitting device applied to WLAN communication. The device may specifically be a first AP, or a component of the first AP (e.g., a processor, a chip, or a chip system). The first AP includes a transceiver unit and a processing unit. The processing unit is configured to generate a radio frame, the radio frame includes a multilink element MLE, the MLE carries information of a first multilink device MLD, the MLE includes first information, and the first information identifies the first MLD. The transceiver unit is configured to transmit the radio frame for the first AP.

[0014] Based on the above technical solution, in a WLAN communication process, a radio frame transmitted by a transceiver unit includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Thus, after receiving the radio frame, a receiver of the radio frame may obtain the information of the first MLD from the MLE based on the first information. In other words, after receiving the radio frame, a receiver of the radio frame may determine that the MLE corresponds to the first MLD based on the first information. Thus, a receiver of the radio frame may obtain information of a station on a plurality of links where the first MLD is located based on the MLE, so that the receiver of the radio frame communicates with the first MLD.

[0015] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency.

[0016] A fourth aspect of an embodiment of this application provides a wireless frame receiving apparatus used in WLAN communication. The apparatus may specifically be an STA or a component of an STA (e.g., a processor, a chip, or a chip system). The apparatus includes a transceiver unit and a processing unit. The transceiver unit is configured to receive a wireless frame from a first access point AP, the wireless frame including a multilink element MLE, the MLE carrying information of a first multilink device MLD, the MLE including first information, the first information identifying the first MLD. The processing unit is configured to obtain the information of the first MLD from the MLE based on the first information.

[0017] Based on the above technical solution, in a WLAN communication process, a wireless frame receiving device functions as a receiver of a wireless frame. A wireless frame received by a transceiver unit in the receiving device includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Thus, the receiver of the wireless frame may obtain the information of the first MLD from the MLE based on the first information after receiving the wireless frame. In other words, after receiving the wireless frame, the receiver of the wireless frame may determine that the MLE corresponds to the first MLD based on the first information. Thus, the receiver of the wireless frame may obtain information of stations on multiple links where the first MLD is located based on the MLE, so that the receiver of the wireless frame communicates with the first MLD.

[0018] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency.

[0019] In one possible implementation of the first to fourth aspects of the embodiment of this application, the first AP does not belong to the first MLD.

[0020] Based on the above technical solution, the MLE included in the wireless frame is information of the first MLD, and the first AP acts as a transmitter of the wireless frame and does not belong to the first MLD. In other words, the device where the first AP is located (which may be a single-link device or a multi-link access point device) is a device other than the first MLD. Therefore, this solution may be applied to a scenario where the first AP transmits information of another MLD (the first MLD). The receiver of the wireless frame may also obtain information of the first MLD based on the wireless frame transmitted by the first AP when the receiver of the wireless frame is not associated with the first AP.

[0021] In one possible implementation of the first to fourth aspects of the embodiment of this application, the first MLD is an MLD in which a second AP is located in the same BSSID set as the first AP. The wireless frame further includes a multi-BSSID element, the multi-BSSID element includes index information of the BSSID of the second AP, and the value of the index information of the BSSID of the second AP is the same as the value of the first information.

[0022] Optionally, the statement that the first MLD is an MLD in which the second AP is located within the same BSSID set as the first AP may also be expressed as follows: The first MLD includes the second AP within the same multiple basic service set identifier BSSID set as the first AP.

[0023] Based on the above technical solution, when the first AP does not belong to the first MLD, the first MLD may specifically be the MLD in which the second AP is located in the same BSSID set as the first AP, so that a Multiple BSSID element (also called a multi-BSSID element) in the radio frame transmitted by the first AP may carry information of the second AP. The multi-BSSID element may carry index information of the BSSID of the second AP. Therefore, when the first MLD corresponding to the MLE in the radio frame includes the second AP, the value of the index information of the BSSID of the second AP in the multi-BSSID element is the same as the value of the first information in the MLE, indicating that the information of the second AP in the multi-BSSID element and the information carried in the MLE correspond to the same MLD (first MLD).

[0024] In one possible implementation of the first to fourth aspects of the embodiment of this application, the MLE includes a first Per-STA profile element, the first Per-STA profile carries information of a third AP, and the third AP belongs to a first MLD. When the first Per-STA profile element does not include the first element of the third AP, the value of the first element of the third AP is the same as the value of the first element of the second AP.

[0025] Optionally, a Non-Inheritance element in the first Per-STA Profile element does not include the first element.

[0026] Optionally, the first Per-STA Profile element is a fully configured element, in other words, a value of a Complete Profile field in the first Per-STA Profile element is 1.

[0027] Optionally, the statement that when the first per-STA profile element does not include the third AP's first element, the value of the third AP's first element is the same as the value of the second AP's first element may also be expressed as follows: When a station's (second AP) first element in a multi-BSSID element carried in a radio frame transmitted by the reporting station (first AP) is not present in the reported station's (third AP) full-profile element, the first element is considered to be part of the reported station's full-profile element, and the value of the first element in the multi-BSSID element is the same as the value of the first element in the reported station's full-profile element, except when the reported station's full-profile element carries a non-inherited element and the first element is present in the non-inherited element.

[0028] Based on the above technical solution, the first MLD may further include a third AP different from the second AP, and the MLE includes a first per-STA profile element for carrying information of the third AP. Since some information of different APs in the same MLD is the same, when the first per-STA profile element does not include the first element of the third AP, the value of the first element of the third AP is the same as the value of the first element of the second AP. Therefore, the first element of the third AP may inherit the first element of the second AP. This makes it easy for the receiver of the wireless frame to determine the first element of the third AP based on the first element of the second AP carried in the multi-BSSID element.

[0029] In one possible implementation of the first to fourth aspects of the embodiment of this application, the MLE further includes a first field, and a first value of the first field indicates that the value of the first element of the third AP is the same as the value of the first element of the second AP.

[0030] Based on the above technical solution, the MLE may further carry a first field. The first value of the first field indicates that the value of the first element of the third AP is the same as the value of the first element of the second AP. In this way, the receiver of the wireless frame determines that the first element of the third AP may inherit the first element of the second AP based on the first field in the MLE. In other words, the receiver of the wireless frame determines that the value of the first element of the third AP is the same as the value of the first element of the second AP based on the first field in the MLE.

[0031] In a possible implementation method of any one of the first to fourth aspects of the embodiment of this application, the first field is located in a Multi-Link Control field in the MLE, or the first field is located in a Common Info field in the MLE.

[0032] In one possible implementation of the first to fourth aspects of the embodiment of this application, the value of the first element of the second AP is the same as the value of the first element of the first AP.

[0033] Optionally, the first element of the AP in the first MLD is located in a Frame body of a wireless frame.

[0034] Optionally, a non-inheritance element in an element of a second AP in a multi-BSSID element does not include the first element.

[0035] Optionally, the element of the second AP in the multi-BSSID element is a fully configured element, in other words, the value of a Complete Profile field in the element of the second AP in the multi-BSSID element is 1.

[0036] Optionally, the statement that the value of the first element of the second AP is the same as the value of the first element of the first AP may also be expressed as follows: When the element of the second AP in the multi-BSSID element does not include the first element of the second AP, the value of the first element of the second AP is the same as the value of the first element of the first AP. Alternatively, the statement may be expressed as follows: When the first element (information indicating the first element of the first AP) carried in the radio frame transmitted by the reporting station (first AP) is not present in the full-profile element of the second AP in the multi-BSSID element, the first element is considered to be part of the full-profile element of the second AP in the multi-BSSID element, and the value of the first element in the full-profile element of the second AP in the multi-BSSID element is the same as the value of the first element in the radio frame, except when the full-profile element of the second AP in the multi-BSSID element carries a non-inherited element and the first element is present in the non-inherited element.

[0037] Based on the above technical solution, some information of different APs in the same multi-BSSID set is the same, so when the multi-BSSID element does not include the first element of the second AP, the value of the first element of the second AP is the same as the value of the first element of the first AP. Therefore, the first element of the second AP may inherit the first element of the first AP. This makes it easy for the receiver of the wireless frame to determine the first element of the third AP based on the first element of the first AP carried in the wireless frame.

[0038] In one possible implementation of the first to fourth aspects of the embodiment of this application, the first MLD includes a fourth AP. The wireless frame further includes a reduced neighbor report (RNR) element, and the RNR element includes information of the fourth AP and includes second information for identifying the first MLD. The value of the first information is the same as the value of the second information.

[0039] Based on the above technical solution, the radio frame further includes an RNR element for reporting information of a fourth AP, and the RNR element includes second information for identifying a first MLD to which the fourth AP belongs, and the value of the first information is the same as the value of the second information. Therefore, if the first MLD corresponding to the MLE in the radio frame includes the fourth AP, the value of the second information in the RNR element for identifying the first MLD to which the fourth AP belongs is the same as the value of the first information in the MLE, indicating that the information of the fourth AP in the RNR element and the information carried in the MLE correspond to the same MLD (the first MLD).

[0040] In one possible implementation of the first to fourth aspects of the embodiment of this application, the MLE includes a second per-STA profile element, and the second per-STA profile element carries information of an AP in the first MLD. When the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

[0041] Optionally, the first MLD may include at least one of the following APs: the second AP, the third AP, and the fourth AP, or the first MLD may include other APs (e.g., other neighboring APs), or the first MLD may include APs corresponding to any per-STA profile element carried in the MLE, which is not limited herein.

[0042] Optionally, the first element of the AP in the first MLD is located in a Frame body of a wireless frame.

[0043] Optionally, the Non-Inheritance element in the second Per-STA Profile element does not include the first element.

[0044] Optionally, the second Per-STA Profile element is a fully configured element, in other words, a value of a Complete Profile field in the second Per-STA Profile element is 1.

[0045] Optionally, the statement that when the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP may also be expressed as follows: When the first element (information indicating the first element of the first AP) carried in a radio frame transmitted by a reporting station (first AP) is not present in the full-profile element of the reported station (AP in the first MLD), the first element is considered to be part of the full-profile element of the reported station, and the value of the first element in the radio frame is the same as the value of the first element in the full-profile element of the reported station, except when the full-profile element of the reported station carries a non-inherited element and the first element is present in the non-inherited element.

[0046] Based on the above technical solution, the MLE includes a second per-STA profile element for carrying information of the AP in the first MLD. Since some information of the first MLD and the first AP (or the MLD in which the first AP is located) is the same, when the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP. Therefore, the first element of the AP in the first MLD may inherit the first element of the first AP. This makes it easy for the receiver of the wireless frame to determine the first element of the AP in the first MLD based on the first element of the first AP carried in the wireless frame.

[0047] In one possible implementation of the first to fourth aspects of the embodiment of this application, the MLE further includes a first field, and a second value of the first field indicates that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

[0048] Based on the above technical solution, the MLE may further carry a first field. The second value of the first field indicates that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP. In this way, the receiver of the wireless frame determines that the first element of the AP in the first MLD can inherit the first element of the first AP based on the first field in the MLE. In other words, the receiver of the wireless frame determines that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP based on the first field in the MLE.

[0049] In one possible implementation of the first to fourth aspects of the embodiment of this application, the first AP belongs to a first MLD.

[0050] Based on the above technical solution, the MLE included in the wireless frame is information of the first MLD, and the first AP acts as a transmitter of the wireless frame and belongs to the first MLD. In other words, the first AP is one of the APs in the first MLD. Therefore, this solution may be applied to a scenario in which the first AP transmits information of the MLD (first MLD) in which the first AP is located. The receiver of the wireless frame may obtain the information of the first MLD based on the wireless frame transmitted by the first AP when the receiver of the wireless frame is associated with the first AP.

[0051] Moreover, compared with the implementation in which the MLE in the radio frame carries information of the MLD where the transmitter of the radio frame is located by default and does not carry indication information, in this solution, the first information in the MLE indicates the MLD corresponding to the MLE, so that the receiver of the radio frame may determine based on the first information that the MLD corresponding to the first MLE is the MLD where the first AP is located. Moreover, the solution may also be used in a scenario in which the radio frame carries an MLE corresponding to an MLD other than the transmitter of the radio frame. In other words, based on the setting of the first information, the solution is applicable to a scenario in which the radio frame carries multiple MLEs corresponding to multiple MLDs (including the MLD where the transmitter of the radio frame is located, i.e., the first MLD).

[0052] In one possible implementation of the first to fourth aspects of the embodiment of this application, the MLE includes a common information field, and the first information is located in the common information field.

[0053] In one possible implementation of the first to fourth aspects of the embodiment of this application, the first information is a multi-link device identifier (MLD ID) field.

[0054] Optionally, the first information may alternatively be another field name, for example, a multilink identifier, a multilink device index, or a multilink index.

[0055] In one possible implementation of the first to fourth aspects of the embodiment of this application, the radio frame further includes a fragmentation element adjacent to the MLE, the MLE carrying a first portion of the information of the first MLD, and the fragmentation element carrying a second portion of the information of the first MLD.

[0056] Based on the above technical solution, in the WLAN communication process, the length of information that can be carried by the MLE may be fixed (for example, 255 octets). Therefore, due to the length limitation, the first case may occur where one MLE is insufficient to carry the information of the first MLD. In this case, different parts of the information of the first MLD may be carried separately in the MLE and one or more fragment elements adjacent to the MLE, so as to ensure that the information of the first MLD is transmitted completely.

[0057] Furthermore, compared with the implementation in which different parts of the information of the MLD are carried in multiple non-adjacent subelements, i.e., carried at positions other than the MLE in the radio frame (for example, the information of the same MLD is carried in different subelements of the data portion of multiple non-transmitted BSSID Profile subelements in the multi-BSSID element of the radio frame), in the above solution, since the MLE and one or more fragment information are adjacent in the radio frame, the receiver of the radio frame may obtain the information of the same MLD from the ML and one or more fragment information adjacent to the MLE, instead of reading the information from the multiple non-adjacent subelements separately, so that the receiver of the radio frame obtains the information of the station of the first MLD, which improves communication efficiency.

[0058] Optionally, the number of information elements contained in the fragment element is 1, the fragment element includes a length field, and the value of the length field is 255 or less.

[0059] Optionally, the fragment element includes n information elements, where the value of the length field of each of the n information elements except for the last information element is 255, where n is an integer greater than 1.

[0060] In one possible implementation of the first to fourth aspects of the embodiment of this application, the radio frame is a Multilink Probe Response frame.

[0061] Based on the above technical solution, the communication method may be applied to a multi-link probe process. After receiving a multi-link probe request frame, the first AP may generate and send a multi-link probe response frame to perform a multi-link probe process.

[0062] A fifth aspect of an embodiment of the present application provides a communication device including at least one processor, the at least one processor coupled to a memory, the memory configured to store a program or instructions, the at least one processor configured to execute the program or instructions, such that the device implements a method according to the first aspect or any one of the possible implementations of the first aspect, or such that the device implements a method according to the second aspect or any one of the possible implementations of the second aspect.

[0063] A sixth aspect of an embodiment of the present application provides a computer-readable storage medium storing one or more computer-executable instructions, which when executed by a processor, cause the processor to perform a method according to the first aspect or any one of the possible implementations of the first aspect, or cause the processor to perform a method according to the second aspect or any one of the possible implementations of the second aspect.

[0064] A seventh aspect of an embodiment of the present application provides a computer program product (also called a computer program) storing one or more computer instructions, which, when executed by a processor, causes the processor to execute a method according to the first aspect or any one of the possible implementations of the first aspect, or causes the processor to execute a method according to the second aspect or any one of the possible implementations of the second aspect.

[0065] An eighth aspect of an embodiment of the present application provides a chip system, the chip system including at least one processor configured to support a communication device in implementing functions in the first aspect or any one of possible implementation manners of the first aspect, or configured to support a communication device in implementing functions in the second aspect or any one of possible implementation manners of the second aspect.

[0066] In a possible design, the chip system further includes a memory. The memory is configured to store program instructions and data required for the communication device. The chip system may include a chip or may include a chip and other discrete components. Optionally, the chip system further includes an interface circuit, which provides the program instructions and / or data for the at least one processor.

[0067] A ninth aspect of an embodiment of the present application provides a communication system, the communication system including the communication device according to the third aspect and the communication device according to the fourth aspect, and / or the communication system including the communication device according to the fifth aspect.

[0068] The technical effects provided by any of the designs in the fifth to ninth aspects refer to the technical effects provided by the different implementation methods in the first to fourth aspects, and the details are not described again here.

[0069] From the above technical solution, it can be seen that in a WLAN communication process, a wireless frame transmitted by a first AP includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Therefore, after receiving the wireless frame, the receiver of the wireless frame may obtain the information of the first MLD from the MLE based on the first information. In other words, after receiving the wireless frame, the receiver of the wireless frame may determine that the MLE corresponds to the first MLD based on the first information. Therefore, the receiver of the wireless frame may obtain, based on the MLE, information of stations on multiple links where the first MLD is located, so that the receiver of the wireless frame communicates with the first MLD.

[0070] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency. [Brief description of the drawings]

[0071] [Figure 1] 1 is a schematic diagram of a communication system according to an embodiment of the present application; [Diagram 2] FIG. 2 is a schematic diagram of a multi-link association according to an embodiment of the present application; [Diagram 3]FIG. 2 is a schematic diagram of a radio frame according to an embodiment of the present application; [Figure 4a] FIG. 2 is another schematic diagram of a radio frame according to an embodiment of the present application. [Figure 4b] FIG. 2 is another schematic diagram of a radio frame according to an embodiment of the present application. [Diagram 5] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 6] 1 is a schematic diagram of a communication method according to an embodiment of the present application; [Figure 7] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 8] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 9] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 10] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 11] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 12] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 13] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 14] FIG. 2 is another schematic diagram of a communication system according to an embodiment of the present application. [Figure 15] 1 is a schematic diagram of a communication device according to an embodiment of the present application; [Figure 16] FIG. 2 is another schematic diagram of a communication device according to an embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0072] Cross-references may be made between embodiments for the same or similar parts in the embodiments of this application. In the embodiments and the implementation methods / methods in the embodiments of this application, unless otherwise specified or logical conflict occurs, the terms and / or descriptions are consistent and may be cross-referenced between different embodiments and between the implementation methods / methods in the embodiments. The technical features in the different embodiments and the implementation methods / methods in the embodiments may be combined to form new embodiments, implementation methods or methods according to their internal logical relationships. The following description of the implementation methods of this application does not constitute any limitation on the protection scope of this application.

[0073] It can be understood that in some scenarios, some optional features in the embodiments of this application may be realized independently, without relying on other features, for example, the solutions on which the optional features are currently based, to solve corresponding technical problems and achieve corresponding effects. Alternatively, in some scenarios, the optional features are combined with other features as necessary. Correspondingly, the devices provided in the embodiments of this application may also realize these features or functions correspondingly. Details will not be described here.

[0074] In the description of this application, "plurality" means two or more unless otherwise specified. "At least one of the following items" or similar expressions refer to any combination of the items, including any combination of singular items or plural items. For example, at least one of a, b, or c may refer to a, b, c, a and b, a and c, b and c, or a, b, and c, where a, b, and c may be singular or plural.

[0075] Furthermore, in order to clearly describe the technical solutions in the embodiments of this application, terms such as "first" and "second" are used in the embodiments of this application to distinguish between the same or similar items that provide essentially the same function or purpose. Those skilled in the art may understand that terms such as "first" and "second" do not limit the number or execution order, and terms such as "first" and "second" do not indicate clear differences. Furthermore, in the embodiments of this application, expressions such as "example" or "for example" are used to represent giving an example, illustration, or explanation. Any embodiment or implementation described as "example" or "for example" in the embodiments of this application should not be described as being preferred or having more advantages than other embodiments or implementations. Rather, the use of expressions such as "example" and "for example" is intended to present a relative concept in a concrete manner for ease of understanding.

[0076] In order to facilitate understanding of the method provided in the embodiment of this application, the system architecture of the method provided in the embodiment of this application is described below. It can be understood that the system architecture described in the embodiment of this application is intended to more clearly describe the technical solutions in the embodiment of this application, and does not constitute any limitation on the technical solutions provided in the embodiment of this application.

[0077] The technical solutions provided in this application are applicable to WLAN scenarios, for example, to IEEE 802.11 system standards, such as 802.11a / b / g, 802.11n, 802.11ac, 802.11ax, or future generations of 802.11ax, such as 802.11be or further future standards.

[0078] Although the embodiments of this application are described primarily by using examples of deployed WLAN networks, particularly networks applying the standard of the IEEE 802.11 system, those skilled in the art will readily appreciate that aspects of this application may be extended to other networks using various standards or protocols, such as Bluetooth, high performance radio LAN (HIPERLAN) (a wireless standard similar to the IEEE 802.11 standard and used primarily in Europe), wide area networks (WANs), personal area networks (PANs), or other networks known or developed in the future. Thus, various aspects provided in this application are applicable to any suitable wireless network, regardless of coverage and wireless access protocol.

[0079] Alternatively, embodiments of this application may be applied to wireless local area network systems, such as internet of things (IoT) or vehicle to all things (V2X) networks. Obviously, embodiments of this application are applicable to other possible communication systems, such as long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, universal mobile telecommunications system (UMTS), worldwide interoperability for microwave access (WiMAX) communication systems, 5th generation (5G) communication systems, and future 6th generation (6G) communication systems.

[0080] The above communication systems used in this application are merely illustrative examples and are not limiting. A general description is provided here. The details will not be described again below.

[0081] The radio frame transmitting method and device and the radio frame receiving method and device provided in the embodiments of this application may be applied to a wireless communication system. The wireless communication system may be a wireless local area network (WLAN) or a cellular network. The method may be implemented by a communication device in the wireless communication system or a chip or processor in the communication device. The communication device may be a wireless communication device capable of parallel transmission on multiple links. For example, the communication device is called a multi-link device (MLD) or a multi-band device. Compared with a device that supports transmission only on a single link, a multi-link device has higher transmission efficiency and higher throughput.

[0082] FIG. 1 is a schematic diagram of a communication system according to an embodiment of the present application.

[0083] As shown in Figure 1, the communication system mainly includes at least one Multi-link AP device and at least one Multi-link non-AP STA device (short for Multi-link station device). The Multi-link access point device and the Multi-link station device may be jointly referred to as Multi-link device. The following provides a description of the Multi-link device.

[0084] A multi-link device includes one or more affiliated stations (denoted as affiliated STAs). An affiliated STA is a logical station and may operate on a single link. An affiliated station may be an access point (AP) or a non-access point station (non-AP STA). For ease of description, in this application, a multi-link device whose affiliated station is an AP may be referred to as a multi-link AP, a multi-link AP device, or an AP multi-link device, and a multi-link device whose affiliated station is a non-AP STA may be referred to as a multi-link STA, a multi-link STA device, or an STA multi-link device. For ease of description, in the embodiments of this application, "a multi-link device includes an affiliated STA" is also simply described as "a multi-link device includes an STA".

[0085] It should be noted that a multi-link device includes multiple logical stations, each of which operates on a single link, although multiple logical stations are permitted to operate on the same link. A link identifier, as referred to below, represents one station operating on one link. In other words, if there is more than one station on one link, then more than one link identifier is used to represent the more than one station. A link, as referred to below, may also represent a station operating on the link.

[0086] During data transmission between the multi-link AP device and the multi-link STA, the link identifier may be used to identify a link or a station on a link. Before communication, the multi-link AP device and the multi-link STA device may negotiate or communicate with each other about the correspondence between the link identifier and the link or the station on the link. Therefore, during data transmission, instead of transmitting a large amount of signaling information for indication, the link identifier is carried to indicate the link or the station on the link. This reduces signaling overhead and improves transmission efficiency.

[0087] In one example, the multilink AP device may transmit a management frame, e.g., a beacon frame, during establishment of a basic service set (BSS), the management frame carrying an element including a plurality of link identifier information fields, and a correspondence between the link identifier and a station operating on the link may be established in each of the link identifier information fields. Each of the link identifier information fields includes a link identifier and may further include one or more of the following: a medium access control (MAC) address, an operating class, and a channel number, and one or more of the MAC address, operating class, and channel number may indicate a link. In another example, in a multilink association establishment process, the multilink AP device and the multilink station device negotiate a plurality of link identifier information fields. In subsequent communications, the multilink AP device or the multilink station device may use a link identifier to represent a station in the multilink device, and the link identifier may further represent one or more attributes of the station's MAC address, operating class, and channel number. The MAC address may alternatively be replaced with the association identifier of the multi-link AP device associated with the station.

[0088] When multiple stations operate on a link, the link identifier (which is a numeric ID) represents the operating class and channel number corresponding to the link, and also represents the identifier of the station operating on the link, e.g., the station's MAC address or association identifier (AID).

[0089] A multilink device may realize wireless communication according to a standard of the 802.11 family. For example, a station supporting extremely high throughput (EHT), or a station supporting 802.11be or a standard in addition to 802.11be, realizes communication with another device. Obviously, the other device may or may not be a multilink device.

[0090] The non-AP MLD in this application may be a wireless communication chip, a wireless sensor, or a wireless communication terminal. For example, examples of the non-AP MLD may be a user terminal, a user device, an access device, a subscriber station, a subscriber unit, a mobile station, a user agent, and a user equipment capable of Wi-Fi communication. The user terminal may be any one of various devices capable of wireless communication such as handheld devices, in-vehicle devices, wearable devices, internet of things (IoT) devices, computing devices, other processing devices connected to a wireless modem, and various types of user equipment (UE), mobile stations (MS), terminals, terminal equipment, portable communication devices, handheld devices, portable computing devices, entertainment devices, gaming devices or systems, global positioning system devices, any other suitable devices configured for network communication over a wireless medium, and the like. Furthermore, the non-AP MLD may support the 802.11be standard or the next generation WLAN standard of 802.11be. Non-AP MLD may also support multiple WLAN standards, such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a.

[0091] The AP MLD in the embodiment of this application may be a device deployed in a wireless communication network to provide wireless communication functions for non-APs associated with the AP MLD. The AP MLD is mainly deployed in homes, buildings and campuses, with a typical coverage radius of tens of meters to hundreds of meters. Obviously, the AP MLD may be alternatively deployed outdoors. The AP MLD, which corresponds to a bridge connecting wired and wireless networks, is mainly configured to connect wireless network clients together and then connect the wireless network to Ethernet. Specifically, the AP MLD may be a communication device with a Wi-Fi chip, such as a base station, a router, a gateway, a repeater, a communication server, a switch or a bridge. The base station may be in various forms, such as a macro base station, a micro base station, a relay station, etc. In addition, the AP MLD may support the 802.11be standard or the next generation WLAN standard of 802.11be. AP MLD may also support WLAN standards such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a.

[0092] As mentioned above, the multilink access point device and the multilink station device may communicate with each other using multiple radio frames, such as an association request frame, a reassociation request frame, an association response frame, a reassociation response frame, and a probe response frame. Different radio frames may carry a multi-link element (MLE) for carrying information of the stations of the multilink device. The MLE may also be referred to as a multilink information unit.

[0093] In the following, the association process of a multilink device is used as an example to describe the specific implementation of the association request frame used in the association process. As shown in Figure 2, in the multilink establishment (or multilink association) process, a station in the multilink station device may send an association request frame to an access point in the multilink access point device, and the association request frame carries an MLE for carrying the information of the current station of the multilink station device and the information of other stations in the multilink device. Similarly, the association response frame returned by the access point to the station may also carry an MLE for carrying the information of the current access point of the multilink access point device and the information of other access points in the multilink device.

[0094] The above is a brief description of the system architecture in the embodiment of this application. In order to better understand the technical solutions in the embodiment of this application, the following describes the relevant contents in the embodiment of this application.

[0095] I.MLE format

[0096] Figure 3 is a schematic diagram of the format of the MLE. The MLE includes an Element ID field (for example, the value of this field may be 255 as shown in Figure 3), a Length field, an Element ID Extension field, a Multi-Link Control field, a Common Info field, and a Link Info field. The Common Info field carries common information of multiple stations in a multi-link device and information of the multi-link device. The Link Info field carries information of stations on each link in the multi-link device. The Multi-Link Control field carries the type of the multi-link element and indication information indicating which fields are present and which are not present in the Common Info field.

[0097] Furthermore, as shown in Figure 3, the Link Information field may further include one or more Per-STA Profile fields. In Figure 3, an example is used in which the number of Per-STA Profile fields is x (x is greater than 1). Each Per-STA Profile field may further include a subelement ID field (e.g., the value of the subelement ID field may be 0 as shown in Figure 3), a Length field, and a Data field.

[0098] Furthermore, as shown in FIG. 3, the data field may further include a Station Control field, a Station Information field, and a Station Profile field.

[0099] Further, as shown in Fig. 3, the STA profile field includes a number of fields. For example, in Fig. 3, the number of fields is m (x is greater than 1). The STA profile field further includes a number of elements. For example, in Fig. 3, the number of elements is n (n is greater than 1). Further, the STA profile field further includes a non-inheritance element (if present).

[0100] However, as shown in FIG. 3, the length of the content that can be carried by the MLE is limited, and the specific length of the MLE is indicated by the length field in the MLE. Specifically, the length field indicates the number of octets that follow the length field in the MLE. For example, the length of the length field in the MLE is 8 bits, which indicates a length of 0 to 255 octets. However, the length of the information that needs to be carried in the MLE may exceed 255 octets, and as a result, only one MLE is insufficient to carry the information of a multilink device.

[0101] Furthermore, the information of stations on each link in a multi-link device is carried in a per-STA profile, which is a subelement in the link information field, but the length of each per-STA profile is also limited. For example, the length field in the per-STA profile is 8 bits long, which allows the data field to carry a maximum of 255 octets. However, the information of stations on each link may be longer than 255 octets, and as a result, only one per-STA profile is insufficient to carry the information of stations on each link.

[0102] II. Multiple BSSIDs

[0103] The current 802.11 standard supports the feature of multiple basic service set identifier sets (multiple BSSIDs, or also called multiple BSSID sets). The basic function of multiple BSSID sets is to form multiple virtual APs in one device to serve different types of STAs. To reduce management costs, multiple virtual APs may be managed centrally.

[0104] A multi-BSSID set may be a combination of several cooperating APs, all of which use the same operating class, the same channel number, and the same antenna port. Generally, in a multi-BSSID set, there are APs that correspond to a transmitted BSSID and APs that correspond to a non-transmitted BSSID. Information about the multi-BSSID set (i.e., a multi-BSSID element) is carried in a management frame (e.g., a beacon frame, a probe response frame, or a neighbor report) transmitted by a transmitting BSSID AP. Information about the BSSID of a non-transmitting BSSID AP is derived based on the multi-BSSID element in a received beacon frame, a probe response frame, or a neighbor report, etc.

[0105] Furthermore, in the multi-BSSID technology, one physical AP may be virtualized into multiple logical APs. Each virtual AP manages one BSS. Usually, different virtual APs have different SSIDs and permissions, such as security mechanisms or transmission opportunities. The BSSID corresponding to one virtual AP among the multiple APs obtained through virtualization is configured as a transmit BSSID. The virtual AP may be called a transmit AP. The BSSID corresponding to the other virtual APs is configured as a non-transmit BSSID. These virtual APs may be called non-transmitted APs. In general, multiple APs in a multi-BSSID may also be understood as multiple cooperative AP devices obtained by virtualizing one AP device. Only the AP whose BSSID is a transmit BSSID can transmit a beacon frame and a probe response frame. If a probe request frame sent by a STA is addressed to an AP whose BSSID is a non-transmit BSSID in a multi-BSSID set, the AP whose BSSID is a transmit BSSID must help respond with a probe response frame. Beacon frames sent by an AP whose BSSID is a transmit BSSID include a multi-BSSID element, and an AP whose BSSID is a non-transmit BSSID cannot send beacon frames. Association identifiers (AIDs) assigned by multiple virtual APs to stations managed by multiple virtual APs share one space, which means that AIDs assigned to stations managed by multiple virtual BSSs cannot be the same.

[0106] Optionally, as shown in Table 1, the multi-BSSID element includes the following fields: element ID, length, maximum BSSID indicator, and sub-element. The value (n) of the maximum BSSID indicator field is for calculating the maximum number of BSSIDs included in the multi-BSSID set, 2^n (i.e., 2 to the power of n). The optional sub-element includes information of each non-transmitting BSSID. The receiving end may calculate the value of each BSSID in the multi-BSSID set based on the base BSSID, the maximum BSSID indicator, and the BSSID index. Each BSSID includes 48 bits. The value of the most significant (48-n) bits of each BSSID in the multi-BSSID set is equal to the value of the most significant (48-n) bits of the base BSSID, and the value of the least significant n bits of each BSSID in the multi-BSSID set is obtained by performing a modulo 2^n operation on the sum of the value of the least significant n bits of the base BSSID and the value of the BSSID index x. The base BSSID (transmitting BSSID) is carried in the BSSID field in the MAC header of the frame (e.g., beacon frame) that includes the multi-BSSID element. For specific calculation methods, please refer to the 802.11-2016 standard. [Table 1]

[0107] Table 2 shows the "optional sub-elements" listed in Table 1. [Table 2]

[0108] Optionally, in Table 2, a Nontransmitted BSSID profile includes a list of elements for one or more APs or directional multi-gigabit stations (DMG STAs) that have a nontransmitted BSSID.

[0109] Optionally, in Table 2, the non-transmitting BSSID profile includes, but is not limited to, the following elements:

[0110] 1. For each non-transmitting BSSID, a non-transmitting BSSID capabilities element is included and a variable number of elements in the beacon frame.

[0111] 2. A service set identifier (SSID) element and a multi-BSSID-index element are included. The multi-BSSID-index element includes a BSSID index field.

[0112] 3. If a Multi-BSSID element is carried in the beacon frame, a First Missing PDCP Sequence Number Descriptor (FMS Descriptor) element is also included.

[0113] 4. The following elements: The Timestamp and Beacon Interval fields, direct sequence spread spectrum parameter set (DSSS Parameter Set), independent basic service set parameter set (IBSS Parameter Set), Country, Channel Switch Announcement, Extended Channel Switch Announcement, Wide Bandwidth Channel Switch, Transmit Power Envelope, and Supported Operating Classes, IBSS DFS, ERP Information, high throughput capabilities (HT Capabilities), HT Operation, VHT Capabilities, VHT Operation, SIG Beacon Compatibility, Short Beacon Interval, SIG Capabilities, SIG Operation, and SIG Operation (11ah) etc. These elements have the same value as that of the transmitting BSSID AP.

[0114] 5. A non-inheritance element (optional) is included, which appears as the last element. The non-inheritance element includes the ID and element ID extension number of a set of elements that the non-transmitting BSSID cannot inherit from the transmitting BSSID. It should be noted that the specific contents of the elements are omitted here. Specifically, as shown in Table 3, the non-inheritance element includes the following fields: element ID, length, element ID extension, element ID list, and element ID extension list. The element ID extension number is present only when the value of the element ID field is 255. [Table 3]

[0115] One implementation of a frame format of a multi-BSSID element for carrying a multi-BSSID set may be shown in FIG. 4a.

[0116] As shown in Fig. 4a, the structure of the radio frame includes two adjacent Multiple BSSID elements. Each of the Multiple BSSID elements includes the following fields: Element ID field (for example, the value of the Element ID field is 71 shown in Fig. 4a), Length field, Max BSSID Indicator field, and Nontransmitted BSSID Profile subelement field (also called Nontransmitted BSSID Profile). There are zero or more Nontransmitted BSSID Profile subelement fields (zero or more Nontransmitted BSSID Profiles). In Fig. 4a, an example is used in which the number of Nontransmitted BSSID Profile subelement fields is i (i is greater than 1).

[0117] Further, as shown in FIG. 4a, a non-transmitting BSSID profile sub-element i (BSSi) includes a sub-element ID field (eg, the value of the sub-element ID field is 0), a length field, and a data field.

[0118] Further, as shown in Fig. 4a, the data field includes a Nontransmitted BSSID Capability element field, a Service Set Identifier element (SSID element), a Multiple BSSID-Index element, one or more elements, and a non-inherited element (if present). In the example shown in Fig. 4a, the Nontransmitted BSSID profile sub-element i in the first Multi-BSSID element includes elements 1 to L, where L is greater than 1, and the Nontransmitted BSSID profile sub-element i in the second Multi-BSSID element includes elements (L+1) to Y, where Y is greater than L.

[0119] In the implementation example shown in Figure 4a, in the Data portion of the non-transmitting BSSID profile subelement, the stations (STAs / APs) corresponding to "Element 1" to "Element L" in the Data portion may be identified by a Basic Service Set Identifier Index (BSSID Index) in a Multiple BSSID-index element.

[0120] Specifically, the multi-BSSID element carries the information of multiple virtual APs in the multi-BSSID set to which the AP belongs. The length field occupies 8 bits, indicating that a maximum of 255 octets can be carried. However, the length of the information of multiple virtual APs may exceed 255 octets. Therefore, multiple multi-BSSID elements are used to carry the information of multiple virtual APs. As shown in FIG. 4a, the first multi-BSSID element carries a first part of the information of BSS1 to BSSi, and the second multi-BSSID element carries the information of BSSi and the remaining part of the information of BSS(i+1). The contents of the two multi-BSSID elements may be concatenated to obtain the information of BSS1 to BSS(i+1). The information of each BSS starts with a non-transmitting BSSID capability element.

[0121] III. Combination of Multi-BSSID and Multi-Link

[0122] For a device that supports both multi-link communication and multiple BSSID sets, multiple BSSIDs may exist on each link, and APs from different multi-BSSID sets may form an MLD, but the transmitting BSSIDs are not necessarily located in the same MLD.

[0123] For example, an implementation of the device structure is shown in FIG.

[0124] For example, in the scenario shown in FIG. 5, four AP MLDs are included. AP MLD1 includes an AP with BSSID-1x number (corresponding to link L1), an AP with BSSID-2y number (corresponding to link L2), and an AP with BSSID-3 number (corresponding to link L3). AP MLD2 includes an AP with BSSID-1z number (corresponding to link L1), an AP with BSSID-2x number (corresponding to link L2), and an AP with BSSID-4y number (corresponding to link L4). AP MLD3 includes an AP with BSSID-1y number (corresponding to link L1), an AP with BSSID-2z number (corresponding to link L2), and an AP with BSSID-4x number (corresponding to link L4). AP MLD4 includes an AP with BSSID-4z number (corresponding to link L4). It should be noted that the link number and link identifier in the drawings are not the same concept. The link identifier represents the following groups to identify a particular AP: the AP's operating set, channel number, and MAC address (or BSSID).

[0125] For example, an AP that ends with the number "x" is an AP that corresponds to a transmit BSSID, and an AP that does not end with the number "x" (e.g., "y" or "z") is an AP that corresponds to a non-transmit BSSID. Specifically, multi-BSSID set 1 on link 1 includes transmit BSSID BSSID-1x and non-transmit BSSIDs BSSID-1z and BSSID-1y, multi-BSSID set 2 on link 2 includes transmit BSSID BSSID-2x and non-transmit BSSIDs BSSID-2z and BSSID-2y, link 3 includes BSSID-3 (which is considered not to belong to the multi-BSSID set, and there is no need to distinguish between transmit and non-transmit BSSIDs), and multi-BSSID set 4 on link 4 includes transmit BSSID BSSID-4x and non-transmit BSSIDs BSSID-4z and BSSID-4y.

[0126] For ease of explanation, hereinafter, "AP corresponding to BSSID-n" is referred to as "AP-n" for short. In the scenario shown in Figure 5, n can be 1x, 1y, 1z, 2x, 2y, 2z, 3, 4x, 4y, 4z, etc.

[0127] In some implementation processes, in the implementation scenario shown in Figure 5, when AP-1x functions as a reporting AP (sender of wireless frame), the wireless frame transmitted by AP-1x may carry an MLE corresponding to the MLD (AP MLD1) in which AP-1x is located. The MLE carries station information of multiple stations (including AP-2y and AP-3) in the AP MLD1. The frame format of the MLE carried in the wireless frame may be the same as the implementation process shown in Figure 3. Generally, the MLE carried in the wireless frame is the MLE corresponding to the MLD in which the reporting AP is located by default. Therefore, the receiver of the wireless frame determines (without needing to include further indication information) that the MLE carried in the wireless frame corresponds to the MLD in which the reporting AP is located.

[0128] For example, AP-1x may feed back a probe response frame in response to a probe request frame of a station (STA). By default, the MLE included in the probe response frame corresponds to the multilink access point device (AP MLD1) to which the AP-1x that transmits the probe response frame belongs, which means that the information carried by the MLE is the station information (information of stations AP-2y and AP-3) of the multilink access point device to which the AP that transmits the wireless frame belongs.

[0129] However, in this scenario, AP-1x may need to feed back information of other MLDs in the wireless frame. For example, the probe request frame of the STA requests information of the MLD (AP MLD2 or AP MLD3) to which the AP corresponding to the nontransmitted basic service set identifier (nontransmitted BSSID) on the link where AP-1x is located belongs. In this case, how AP-1x feeds back the wireless frame is an urgent technical problem to be solved.

[0130] Figure 6 is a schematic diagram of a communication method according to this application. The method includes the following steps. As shown in Figure 6, it can be understood that the communication method relates to the transmission of a radio frame. Therefore, the communication method can also be called a radio frame sending method, or a radio frame receiving method.

[0131] S101: A wireless frame transmitting device generates a wireless frame.

[0132] In this embodiment, in step S101, a radio frame transmitting device generates a radio frame. The radio frame includes an MLE, the MLE carries information of a first MLD, the MLE includes first information, and the first information identifies the first MLD.

[0133] The wireless frame transmitting device may be the first AP or a component of the first AP (eg, a processor, a chip, or a chip system).

[0134] S102: The wireless frame transmitting device transmits a wireless frame.

[0135] In this embodiment, after generating a radio frame in S101, the radio frame transmitting device transmits the radio frame in S102, and therefore the radio frame receiving device receives the radio frame in S102.

[0136] The wireless frame transmitting device may be a STA or a component of a STA (eg, a processor, a chip, or a chip system).

[0137] Optionally, the first AP may perform pre-transmission processing on the wireless frame, and in step S102, transmit the processing result obtained through the pre-transmission processing. For example, the pre-transmission processing may include encryption, scrambling, etc. Thus, the STA may receive the processing result (obtained by the first AP performing pre-transmission processing on the wireless frame), and in step S102, perform pre-reception processing on the processing result to obtain the wireless frame. For example, the pre-reception processing may include decryption, descrambling, etc.

[0138] S103: The wireless frame receiving device acquires information of the first MLD from the MLE based on the first information.

[0139] In a possible implementation, the radio frame is a multilink probe response frame. Specifically, the communication method shown in Figure 6 may be applied to a multilink probe process. After receiving the multilink probe request frame, the first AP may generate and send a multilink probe response frame to perform a multilink probe process.

[0140] In a possible implementation, in the MLE included in the wireless frame transmitted by the first AP in step S102, the first information is a multilink device identifier (MLD ID) field. Specifically, the first information may alternatively be other field names, such as a multilink identifier, a multilink device index, or a multilink index.

[0141] For example, the MLE included in the wireless frame transmitted by the first AP in step S102 may include a common information field, and the first information may be located in the common information field. FIG. 7 is an example of an implementation of the format of the MLE in the wireless frame. For the definition of the elements / fields included in FIG. 7, refer to the above description regarding FIG. 3. The first information may be located in a "Common Info" field of a "Multi-Link element" in a "Frame Body" in the wireless frame. In FIG. 7, an example is used in which the first information is named "Multi-Link Identifier (MLD ID)".

[0142] In a possible implementation, in step S102, the MLE carried in the radio frame corresponds to the first MLD identified by the first information, the first AP serves as the reporting AP (sender) of the radio frame, and the association relationship between the first AP and the first MLD may be implemented differently. For example, a value of the first information (MLD ID field) equal to 0 indicates that the MLE in the radio frame carries the information of the MLD in which the first AP is located. A value of the first information (MLD ID field) equal to another value indicates that the MLE in the radio frame carries the information of another MLD.

[0143] Optionally, the "other MLD" may be an MLD that is collocated with the first AP. A "collocated MLD" with the first AP may refer to an MLD that is located on the same physical device as the first AP. Furthermore, the first AP may know the attributes of an MLD that is collocated with the first AP without having to perform signal detection or measurements.

[0144] Optionally, the "other MLD" may alternatively be an MLD to which other APs in the same multi-BSSID set as the first AP belong, or an MLD to which other APs belong that is carried in an RNR element in a radio frame by the first AP, or may be another implementation, which is not limited here.

[0145] The following provides an explanation using a concrete example.

[0146] Implementation method 1: The first AP does not belong to the first MLD.

[0147] Specifically, the MLE included in the wireless frame transmitted by the first AP in step S102 is information of the first MLD, and the first AP functions as a transmitter of the wireless frame and does not belong to the first MLD. In other words, the device where the first AP is located (which may be a single-link device or a multi-link access point device) is a device other than the first MLD. Therefore, this solution may be applied to a scenario in which the first AP transmits information of another MLD (the first MLD). The receiver of the wireless frame may also obtain information of the first MLD based on the wireless frame transmitted by the first AP in step S103 if the receiver of the wireless frame is not associated with the first AP.

[0148] For example, the scenario shown in Fig. 5 is used as an implementation example. For example, AP-1x functions as a reporting AP (the first AP that transmits a wireless frame in step S102). When the first AP does not belong to the first MLD, the first MLD may be an AP MLD other than AP MLD1, for example, AP MLD2, AP MLD3, and AP MLD4.

[0149] In addition, if the first AP does not belong to the first MLD, the first MLD may have multiple implementation methods. The following provides an explanation using a specific example.

[0150] In a possible implementation of implementation 1, the first MLD is the MLD in which the second AP is located, which is in the same BSSID set as the first AP.

[0151] For example, the scenario shown in Fig. 5 is used as an implementation example. For example, AP-1x serves as a reporting AP (the first AP that transmits a wireless frame in step S102). When the first AP does not belong to the first MLD, the first MLD may be the MLD to which the AP belongs, and the AP and AP-1x are located on the same link. In other words, the first MLD is the AP MLD2 to which AP-1z belongs or the AP MLD3 to which AP-1y belongs.

[0152] In this implementation, the wireless frame sent by the first AP in step S102 further includes a multi-BSSID element, which includes index information of the BSSID of the second AP, and the value of the index information of the BSSID of the second AP is the same as that of the first information.

[0153] Optionally, the statement that the first MLD is an MLD in which the second AP is located within the same BSSID set as the first AP may also be expressed as follows: The first MLD includes the second AP within the same multiple basic service set identifier BSSID set as the first AP.

[0154] Specifically, when the first AP does not belong to the first MLD, the first MLD may specifically be the MLD in which the second AP is located in the same BSSID set as the first AP, so that a Multiple Basic Service Set Identifier element (also called a multi-BSSID element) in a radio frame transmitted by the first AP may carry information of the second AP. The multi-BSSID element may carry index information of the BSSID of the second AP. Thus, when the first MLD corresponding to the MLE in the radio frame includes the second AP, the value of the index information of the BSSID of the second AP in the multi-BSSID element is the same as the value of the first information in the MLE, indicating that the information of the second AP in the multi-BSSID element and the information carried in the MLE correspond to the same MLD (first MLD).

[0155] The format shown in FIG. 8 is an implementation example of a multi-BSSID element included in the radio frame transmitted by the first AP in step S102. For the definition of the elements / fields included in FIG. 8, refer to the above description of FIG. 4a. Specifically, when the non-transmitting BSSID profile sub-element (BSS1) shown in FIG. 8 corresponds to the BSS of the second AP, the multi-BSSID-index element in the data part in the non-transmitting BSSID profile sub-element (BSS1) carries a basic service set identifier index (BSSID Index) for identifying the BSSID index of the second AP. In this case, in the radio frame transmitted in step S102, the first AP sets the value of the index information of the BSSID of the second AP in the multi-BSSID element to be the same as the value of the first information in the MLE, indicating that the information of the second AP in the multi-BSSID element and the information carried in the MLE correspond to the same MLD (first MLD).

[0156] The format shown in Fig. 9 is another implementation example of the multi-BSSID element and the multi-link element (MLE) included in the wireless frame transmitted by the first AP in step S102. For the definition of the elements / fields included in Fig. 9, please refer to the explanation in Fig. 3 and Fig. 4a. Specifically, as shown in Fig. 9, the two fields indicated by the dashed boxes have the same value, which means that the value of the field "BSSID index" in the multi-BSSID element is the same as the value of the field "MLD ID" in the multi-link element.

[0157] In a possible implementation, the MLE included in the wireless frame sent by the first AP in step S102 includes a first per-STA profile element, the first per-STA profile element carries information of a third AP, and the third AP belongs to the first MLD. When the first per-STA profile element does not include the first element of the third AP, the value of the first element of the third AP is the same as the value of the first element of the second AP.

[0158] For example, the scenario shown in FIG. 5 is used as an implementation example. For example, AP-1x serves as a reporting AP (the first AP that transmits a wireless frame in step S102). When the first AP does not belong to the first MLD, the first MLD may be the MLD to which the AP belongs, and the AP and AP-1x are located on the same link. In other words, the first MLD is the AP MLD2 to which AP-1z belongs or the AP MLD3 to which AP-1y belongs. Assuming that the first MLD is the AP MLD2 to which AP-1z belongs, the second AP may be AP-1z, and the third AP may be AP-2x or AP-4y.

[0159] Optionally, a Non-Inheritance element in the first Per-STA Profile element does not include the first element.

[0160] Optionally, the first Per-STA Profile element is a fully configured element, in other words, a value of a Complete Profile field in the first Per-STA Profile element is 1.

[0161] Optionally, the statement that when the first per-STA profile element does not include the third AP's first element, the value of the third AP's first element is the same as the value of the second AP's first element may also be expressed as follows: When a station's (second AP's) first element in a multi-BSSID element carried in a radio frame transmitted by the reporting station (first AP) is not present in the reported station's (third AP's) full-profile element, the first element is considered to be part of the reported station's full-profile element, and the value of the first element in the multi-BSSID element is the same as the value of the first element in the reported station's full-profile element, except when the reported station's full-profile element carries a non-inherited element and the first element is present in the non-inherited element.

[0162] Specifically, the first MLD may further include a third AP different from the second AP, and the MLE includes a first per-STA profile element for carrying information of the third AP. Since some information of different APs in the same MLD is the same, when the first per-STA profile element does not include the first element of the third AP, the value of the first element of the third AP is the same as the value of the first element of the second AP. Therefore, the first element of the third AP may inherit the first element of the second AP. This makes it easy for the receiver of the wireless frame to determine the first element of the third AP based on the first element of the second AP carried in the multi-BSSID element in step 103.

[0163] Furthermore, the MLE included in the radio frame transmitted by the first AP in step S102 may further include a first field. The first value of the first field indicates that the value of the first element of the third AP is the same as the value of the first element of the second AP. Specifically, the MLE may further carry a first field. The first value of the first field indicates that the value of the first element of the third AP is the same as the value of the first element of the second AP. In this way, the receiver of the radio frame determines that the first element of the third AP may inherit the first element of the second AP based on the first field in the MLE in step S103. In other words, the receiver of the radio frame determines that the value of the first element of the third AP is the same as the value of the first element of the second AP based on the first field in the MLE in step S103.

[0164] Furthermore, the first field is located in a Multi-Link Control field in the MLE, or the first field is located in a Common Info field in the MLE.

[0165] The format shown in Fig. 10 is an example of the implementation of a multi-BSSID element and a multi-link element (MLE) included in the radio frame transmitted by the first AP in step S102. For the definition of the elements / fields included in Fig. 10, refer to the descriptions of Fig. 3 and Fig. 4a. In Fig. 10, for example, the first field is named "Inheritance Mode" (the first field may alternatively be named differently). The first field is located in a "Common Info" field in the "Multi-Link element (MLE)".

[0166] The format shown in Figure 11 is another implementation example. Different from the format shown in Figure 10, the first field in the format shown in Figure 11 is located in the "Multi-Link Control" field in the "Multi-Link element (MLE)".

[0167] In a possible implementation, the value of the first element of the second AP is the same as the value of the first element of the first AP.

[0168] Optionally, the first element of the AP in the first MLD is located in a Frame body of a wireless frame.

[0169] Optionally, a non-inheritance element in an element of a second AP in a multi-BSSID element does not include the first element.

[0170] Optionally, the element of the second AP in the multi-BSSID element is a fully configured element, in other words, the value of a Complete Profile field in the element of the second AP in the multi-BSSID element is 1.

[0171] Optionally, the statement that the value of the first element of the second AP is the same as the value of the first element of the first AP may also be expressed as follows: When the element of the second AP in the multi-BSSID element does not include the first element of the second AP, the value of the first element of the second AP is the same as the value of the first element of the first AP. Alternatively, the statement may be expressed as follows: When the first element (information indicating the first element of the first AP) carried in the radio frame transmitted by the reporting station (first AP) is not present in the full-profile element of the second AP in the multi-BSSID element, the first element is considered to be part of the full-profile element of the second AP in the multi-BSSID element, and the value of the first element in the full-profile element of the second AP in the multi-BSSID element is the same as the value of the first element in the radio frame, except when the full-profile element of the second AP in the multi-BSSID element carries a non-inherited element and the first element is present in the non-inherited element.

[0172] Based on the above technical solution, some information of different APs in the same multi-BSSID set is the same, so when the multi-BSSID element does not include the first element of the second AP, the value of the first element of the second AP is the same as the value of the first element of the first AP. Therefore, the first element of the second AP may inherit the first element of the first AP. This makes it easy for the receiver of the wireless frame to determine the first element of the third AP based on the first element of the first AP carried in the wireless frame in step S103.

[0173] In another possible implementation of the implementation 1, the first MLD includes a fourth AP, and the information of the fourth AP is carried in an RNR element in a radio frame.

[0174] The radio frame transmitted by the first AP in step S102 further includes an RNR element, where the RNR element includes information of the fourth AP and includes second information for identifying the first MLD. The value of the first information is the same as the value of the second information. Specifically, the radio frame further includes an RNR element for reporting information of the fourth AP. The RNR element includes second information for identifying the first MLD to which the fourth AP belongs, and the value of the first information is the same as the value of the second information. Therefore, when the first MLD corresponding to the MLE in the radio frame includes the fourth AP, the value of the second information in the RNR element for identifying the first MLD to which the fourth AP belongs is the same as the value of the first information in the MLE, indicating that the information of the fourth AP in the RNR element and the information carried in the MLE correspond to the same MLD (first MLD).

[0175] Optionally, the first MLD may include at least one of the following APs: the second AP, the third AP, and the fourth AP, or the first MLD may include other APs (e.g., other neighboring APs), or the first MLD may include APs corresponding to any per-STA profile element carried in the MLE, which is not limited herein.

[0176] FIG. 12 shows an example implementation of the RNR element.

[0177] Specifically, for an AP, the reduced neighborhood report element is carried in a management frame, such as a beacon frame or a probe response frame. When scanning, a station STA receives an association frame sent by an AP, obtains information of surrounding APs, and then selects an appropriate AP for association.

[0178] In this embodiment and the following embodiments, the neighboring AP may specifically be an AP around the AP (herein referred to as the target AP) that transmits the Reduced Neighbor Report element (RNR element for short). For example, the neighboring AP is an AP on another link within the AP MLD in which the target AP is located. In another example, the neighboring AP is an AP adjacent to the target AP. In another example, the neighboring AP is an AP detected in the operating area of ​​the target AP. In another example, the neighboring AP is an AP that is co-located with the target AP. Alternatively, the AP may be defined in other ways, which are not specifically limited here.

[0179] Specifically, the RNR element indicates information of one or more neighboring APs on a particular channel. FIG. 12 shows the frame format of the RNR element, which includes an element identifier (Element ID) field and a length (Length) field indicating the length of the information carried. In addition, each RNR element carries one or more neighboring AP information (Neighbor AP info) fields. The neighboring AP information field may also be referred to as the neighboring AP information field for short. The following provides a description of the information contained in each neighboring AP information field with reference to FIG. 12. Each neighboring AP information field includes the following information:

[0180] 1. Target beacon transmission times information header (TBTT info Header) field

[0181] 2. Operating Class field: indicates the operating class to which the reporting neighbor AP's operating channel belongs. Values ​​such as 0 and 255 are reserved in this field.

[0182] 3. Channel Number field: indicates the channel number corresponding to the operation channel of the reporting neighbor AP. In this field, the value 0 in the channel number field is a reserved value. Furthermore, the STA may determine the specific location of the AP's channel on the frequency band based on the operation class field and the channel number field.

[0183] 4. TBTT info set field: includes one or more TBTT information fields. Furthermore, the frame format of each TBTT information field may be implemented in the manner shown in Figure 12. As shown in Figure 12, each TBTT information field may include the following information:

[0184] Neighbor AP TBTT offset field: indicates the offset between the beacon transmit time for the BSS of the reporting neighbor AP and the beacon transmit time for the BSS for sending the report. The offset is measured in time units (TU), where one TU is equal to 1024 microseconds or 1 millisecond. A value of 254 indicates an offset of 254 TUs or more, and a value of 255 indicates an unknown offset value. The number of bits occupied by the field may be 1.

[0185] b. BSS Identifier (BSSID) field: indicates the BSS identifier corresponding to the BSS being reported. The number of octets occupied by this field may be 0 or 6. This field is optional.

[0186] c. Short Service Set Identifier (Short SSID) field: indicates the service set identifier to which the BSS belongs. The number of octets occupied by this field may be 0 or 4. This field is optional.

[0187] d. BSS Parameter field: indicates the relevant parameters of the BSS. The number of octets occupied by this field may be 0 or 1. This field is optional.

[0188] e. 20MHz power spectral density (PSD) field: indicates the maximum transmit power spectral density. This field is optional. The number of octets occupied by this field may be 0 or 1.

[0189] f. Multilink Device Parameters (MLD Parameters) field: indicates MLD related parameters. The number of octets occupied by this field may be 0 or 3. The MLD Parameters field includes the following subfields: A Multilink Device Identifier (MLD ID) subfield occupying 8 bits and indicating the identifier of the AP MLD, a Link ID subfield occupying 4 bits and indicating the link identifier corresponding to the reporting neighbor AP, a BSS Parameters Change Count subfield occupying 8 bits and indicating the BSS parameters change counter, and a Reserved subfield occupying 4 bits. When a key change occurs in the reporting AP, the BSS parameters change counter is incremented. Otherwise, the BSS parameters change counter remains unchanged.

[0190] Therefore, when the "Multilink Device Identifier (MLD ID) subfield" in the Multilink Device Parameters field shown in Fig. 12 corresponds to the first MLD in which the fourth AP is located, the "Multilink Device Identifier (MLD ID) subfield" in the Multilink Device Parameters field identifies the first MLD to which the fourth AP belongs. In this case, in the wireless frame transmitted in step S102, the first AP sets the value of the "Multilink Device Identifier (MLD ID) subfield" in the Multilink Device Parameters field to be the same as the value of the first information in the MLE, indicating that the first MLD to which the fourth AP belongs, identified by the "Multilink Device Identifier (MLD ID) subfield" in the Multilink Device Parameters field, and the information carried by the MLE, correspond to the same MLD (first MLD).

[0191] Furthermore, the MLE included in the wireless frame transmitted by the first AP in step S102 includes a second per-STA profile element, and the second per-STA profile element carries information of the AP in the first MLD. When the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

[0192] Optionally, the first element of the AP in the first MLD is located in a Frame body of a wireless frame.

[0193] Optionally, the Non-Inheritance element in the second Per-STA Profile element does not include the first element.

[0194] Optionally, the second Per-STA Profile element is a fully configured element, in other words, a value of a Complete Profile field in the second Per-STA Profile element is 1.

[0195] Optionally, the statement that when the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP may also be expressed as follows: When the first element (information indicating the first element of the first AP) carried in a radio frame transmitted by a reporting station (first AP) is not present in the full-profile element of the reported station (AP in the first MLD), the first element is considered to be part of the full-profile element of the reported station, and the value of the first element in the radio frame is the same as the value of the first element in the full-profile element of the reported station, except when the full-profile element of the reported station carries a non-inherited element and the first element is present in the non-inherited element.

[0196] Based on the above technical solution, the MLE includes a second per-STA profile element for carrying information of the AP in the first MLD. Since some information of the first MLD is the same as that of the first AP (or the MLD in which the first AP is located), when the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the AP in the first MLD. Therefore, the first element of the AP in the first MLD may inherit the first element of the first AP. This makes it easy for the receiver of the wireless frame to determine the first element of the AP in the first MLD based on the first element of the first AP carried in the wireless frame in step S103.

[0197] Further, the MLE may further include a first field. A second value of the first field indicates that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP. Specifically, the MLE may further carry a first field. The second value of the first field indicates that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP. In this way, the receiver of the wireless frame determines that the first element of the AP in the first MLD may succeed the first element of the first AP based on the first field in the MLE in step S103. In other words, the receiver of the wireless frame determines that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP based on the first field in the MLE in step S103.

[0198] Optionally, for the realization process of the first field, refer to the above description (including FIG. 10 and FIG. 11), and the details will not be described again here.

[0199] Implementation method 2: The first AP belongs to the first MLD.

[0200] In the implementation method 2, the MLE included in the wireless frame is information of the first MLD, and the first AP functions as a transmitter of the wireless frame and belongs to the first MLD. In other words, the first AP is one of the APs in the first MLD. Therefore, this solution may be applied to a scenario in which the first AP transmits information of the MLD (first MLD) in which the first AP is located. In step S103, the receiver of the wireless frame may obtain information of the first MLD based on the wireless frame transmitted by the first AP if the receiver of the wireless frame is associated with the first AP.

[0201] Moreover, compared with the implementation in which the MLE in the radio frame carries information of the MLD where the transmitter of the radio frame is located by default and does not carry indication information, in this solution, the first information in the MLE indicates the MLD corresponding to the MLE, so that the receiver of the radio frame may determine in step S103 based on the first information that the MLD corresponding to the first MLE is the MLD where the first AP is located. Moreover, the solution may also be used in a scenario in which the radio frame carries an MLE corresponding to an MLD other than the transmitter of the radio frame. In other words, based on the setting of the first information, the solution is applicable to a scenario in which the radio frame carries multiple MLEs corresponding to multiple MLDs (including the MLD where the transmitter of the radio frame is located, i.e., the first MLD).

[0202] For example, the scenario shown in Figure 5 is used as an implementation example. For example, AP-1x serves as a reporting AP (the first AP that transmits a wireless frame in step S102). When the first AP belongs to the first MLD, the first MLD may be AP MLD1, which means that the information of the first MLD carried in the MLE includes the information of stations AP-2y and AP-3.

[0203] In conclusion, based on the description in the implementation method 1 or 2, it can be seen that the wireless frame transmitted by the first AP in step S102 includes an MLE for carrying information of the first MLD, and the MLE includes first information for identifying the first MLD. Therefore, after receiving the wireless frame, the receiver of the wireless frame may obtain the information of the first MLD from the MLE based on the first information in step S103. In other words, after receiving the wireless frame, the receiver of the wireless frame may determine that the MLE corresponds to the first MLD based on the first information in step S103. Compared with the implementation method in which the MLE in the wireless frame carries information of the MLD where the transmitter of the wireless frame is located by default and does not carry indication information, the wireless frame cannot transmit the MLE corresponding to other MLDs, in this solution, based on the setting of the first information, the MLE carried in the wireless frame may carry the MLE corresponding to the MLD other than the transmitter of the wireless frame. Therefore, the receiver of the wireless frame may obtain information of stations on multiple links on which the first MLD is located based on the MLE, thereby causing the receiver of the wireless frame to communicate with the first MLD.

[0204] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the radio frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the radio frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the radio frame may determine the MLD corresponding to the MLE in step S103 based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby obtaining the information of the station of the first MLD in step S103. This improves communication efficiency.

[0205] In the implementation scenario shown in FIG. 5, when AP-1x functions as a reporting AP (sender of wireless frames), the wireless frames transmitted by AP-1x may carry MLEs corresponding to the MLDs (AP MLD2 and AP MLD3) in which other APs in the same multi-BSSID set (multi-BSSID set 1 on link 1) as AP-1x are located, one of the MLEs carrying station information of multiple stations (including AP-2x and AP-4y) in AP MLD2, and the other MLE carrying station information of multiple stations (including AP-2z and AP-4x) in AP MLD3.

[0206] An MLE for carrying station information of multiple stations (including AP-2x and AP-4y) in AP MLD2 is used as an example. The MLE is carried in the Data portion of a non-transmitting BSSID profile sub-element (BSSi, i.e., the BSS corresponding to AP-1z) in the format shown in Fig. 4a. For example, the MLE is located in any one of "Element 1" to "Element L".

[0207] Since the length of each "Element" is limited, when AP MLD2 contains a large amount of information, multiple non-transmitting BSSID profile sub-elements may be used to carry the MLE corresponding to AP MLD2. For the implementation process, refer to the implementation example shown in FIG. 4b. Compared with the implementation process in FIG. 4a, FIG. 4b details that "Element L" in the Data part of the non-transmitting BSSID profile sub-element carries a part of the MLE (for the implementation example of the MLE, refer to the description in FIG. 3), and "Element L+1" in the Data part of another non-transmitting BSSID profile sub-element carries the other part of the MLE. From the above description in FIG. 4a, it can be seen that the Basic Service Set Identifier Index (BSSID Index) in the Multiple BSSID-Index element may identify the station (STA / AP) corresponding to "Element 1" to "Element L" in the Data part. In other words, in the implementation example shown in FIG. 4b, the value of the Basic Service Set Identifier Index (BSSID Index) in the Multiple BSSID-Index element is the BSSID of AP-1z, which indirectly indicates that the MLD carried by “Element L and Element L+1” belongs to the MLD to which AP-1z belongs.

[0208] However, in the implementation shown in FIG. 4b, if the MLE carried in the radio frame needs to be fragmented due to its long length, the analysis complexity is high for the receiver of the radio frame since the transmission in case of fragmentation of the MLE carried in the multi-BSSID element is complicated.

[0209] Therefore, in the communication method shown in FIG. 6, the above problems can be solved by improving the information carried in the radio frames.

[0210] In a possible implementation, the radio frame sent by the first AP in step S102 further includes a fragment element adjacent to an MLE, where the MLE carries a first part of the information of the first MLD, and the fragment element carries a second part of the information of the first MLD.

[0211] Specifically, in the WLAN communication process, the length of information that can be carried by the MLE may be fixed (e.g., 255 octets). Therefore, due to the length limitation, the first case may occur in which one MLE is insufficient to carry the information of the first MLD. In this case, different parts of the information of the first MLD may be carried separately in the MLE and one or more fragment elements adjacent to the MLE, so as to ensure that the information of the first MLD is transmitted completely.

[0212] Furthermore, compared with the implementation in which different parts of the information of the MLD are carried in multiple non-adjacent subelements, i.e., carried at positions other than the MLE in the radio frame (for example, the information of the same MLD is carried in different subelements in the data portion of multiple non-transmitted BSSID Profile subelements in the multi-BSSID element of the radio frame), in the above solution, since the MLE and one or more fragment information are adjacent in the radio frame, the receiver of the radio frame may obtain the information of the same MLD from the ML and one or more fragment information adjacent to the MLE in step S103, instead of separately reading the information from multiple non-adjacent subelements, thereby obtaining the station information of the first MLD in step S103. This improves communication efficiency.

[0213] Compared with the implementation process shown in Fig. 4b, in the above solution, when the information carried in the MLE in the radio frame is relatively long (e.g., when the length of the MLE is greater than 255 octets), fragmentation needs to be performed. As shown in Fig. 4b, since the MLE is no longer located in the multi-BSSID element but outside the multi-BSSID element, fragmentation does not need to be performed for the multi-BSSID element because the multi-BSSID element does not become excessively long.

[0214] For example, when an MLE is fragmented separately, the MLE may be fragmented into one MLE and one or more fragment elements.

[0215] The format shown in Fig. 13 is an example of the implementation of a multi-BSSID element, a multi-link element (MLE), and a fragment element included in the wireless frame transmitted by the first AP in step S102. For the definition of the elements / fields included in Fig. 13, please refer to the descriptions in Fig. 3 and Fig. 4a.

[0216] In the example shown in FIG. 13, the number of information elements included in the fragment element is 1, the fragment element includes a length field, and the value of the length field is 255 or less.

[0217] The format shown in Fig. 14 is another implementation example. Unlike the format shown in Fig. 13, the format shown in Fig. 14 includes multiple fragment elements.

[0218] In the example shown in FIG. 14, the fragment element includes n information elements, and the value of the length field of each of the n information elements except for the last information element is 255, where n is an integer greater than 1.

[0219] Above, the application is described from a method perspective, below, the application is further described from an apparatus perspective.

[0220] 15 is a schematic diagram of a communication device 1500 according to an embodiment of this application. The communication device 1500 includes a processing unit 1501 and a transceiver unit 1502.

[0221] In an implementation manner, the communication device 1500 may specifically be a radio frame transmitting device configured to realize the radio frame transmitting method in the embodiment shown in Fig. 6. Correspondingly, the processing unit 1501 and the transceiver unit 1502 may be configured to perform the following processes:

[0222] The processing unit 1501 is configured to generate a radio frame, where the radio frame includes a multilink element MLE, where the MLE carries information of a first multilink device MLD, where the MLE includes first information, where the first information identifies the first MLD.

[0223] The transceiver unit 1502 is configured to transmit wireless frames for the first AP.

[0224] Based on the above technical solution, in a WLAN communication process, a radio frame transmitted by the transceiver unit 1502 includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Thus, after receiving the radio frame, the receiver of the radio frame may obtain the information of the first MLD from the MLE based on the first information. In other words, after receiving the radio frame, the receiver of the radio frame may determine that the MLE corresponds to the first MLD based on the first information. Thus, the receiver of the radio frame may obtain, based on the MLE, information of stations on multiple links where the first MLD is located, so that the receiver of the radio frame communicates with the first MLD.

[0225] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency.

[0226] In another implementation manner, the communication device 1500 may alternatively be a wireless frame receiving device configured to implement the wireless frame receiving method in the embodiment shown in Fig. 6. Correspondingly, the processing unit 1501 and the transceiver unit 1502 may be configured to perform the following processes:

[0227] The transceiver unit 1502 is configured to receive a wireless frame from a first access point AP, the wireless frame including a multilink element MLE, the MLE carrying information of a first multilink device MLD, the MLE including first information, the first information identifying the first MLD.

[0228] The processing unit 1501 is configured to obtain information of the first MLD from the MLE based on the first information.

[0229] Based on the above technical solution, in a WLAN communication process, a wireless frame receiving device functions as a receiver of a wireless frame. The wireless frame received by the transceiver unit 1502 in the receiving device includes an MLE for carrying information of a first MLD, and the MLE includes first information for identifying the first MLD. Therefore, the receiver of the wireless frame may obtain the information of the first MLD from the MLE based on the first information after receiving the wireless frame. In other words, after receiving the wireless frame, the receiver of the wireless frame may determine that the MLE corresponds to the first MLD based on the first information. Therefore, the receiver of the wireless frame may obtain the information of the station on the multiple links where the first MLD is located based on the MLE, so that the receiver of the wireless frame communicates with the first MLD.

[0230] Furthermore, compared with an implementation in which a field indirectly indicating the MLD corresponding to the MLE is carried at a position other than the MLE in the wireless frame (for example, a basic service set identifier index (BSSID Index) is carried in a multiple BSSID-index element in the multiple BSSID element of the wireless frame to indirectly indicate the MLD to which the AP / STA corresponding to the MLE in the multiple BSSID element belongs, and the AP / STA is indicated by the SSID), in the above implementation, the MLE includes the first information (in other words, the first information is carried inside the MLE), so that the receiver of the wireless frame may determine the MLD corresponding to the MLE based on the MLE without needing to obtain an indirect instruction from outside the MLE, thereby allowing the receiver of the wireless frame to obtain information of the station in the first MLD. This improves communication efficiency.

[0231] In a possible implementation, the first AP does not belong to the first MLD.

[0232] In a possible implementation, the first MLD is an MLD in which a second AP is located in the same BSSID set as the first AP, and the wireless frame further includes a multi-BSSID element, the multi-BSSID element includes index information of the BSSID of the second AP, and the value of the index information of the BSSID of the second AP is the same as the value of the first information.

[0233] Optionally, the statement that the first MLD is an MLD in which the second AP is located within the same BSSID set as the first AP may also be expressed as follows: The first MLD includes the second AP within the same multiple basic service set identifier BSSID set as the first AP.

[0234] In a possible implementation, the MLE includes a first Per-STA profile element, the first Per-STA profile carries information of a third AP, and the third AP belongs to the first MLD. When the first Per-STA profile element does not include the first element of the third AP, the value of the first element of the third AP is the same as the value of the first element of the second AP.

[0235] In a possible implementation, the MLE further includes a first field, where a first value of the first field indicates that the value of the first element of the third AP is the same as the value of the first element of the second AP.

[0236] In a possible implementation, the first field is located in a Multi-Link Control field in the MLE, or the first field is located in a Common Info field in the MLE.

[0237] In a possible implementation, the value of the first element of the second AP is the same as the value of the first element of the first AP.

[0238] Optionally, the first element of the AP in the first MLD is located in a Frame body of a wireless frame.

[0239] In a possible implementation, the first MLD includes a fourth AP. The radio frame further includes a reduced neighbor report (RNR) element. The RNR element includes information of the fourth AP and includes second information for identifying the first MLD. The value of the first information is the same as the value of the second information.

[0240] In a possible implementation, the MLE includes a second per-STA profile element, and the second per-STA profile element carries information of an AP in the first MLD. When the second per-STA profile element does not include the first element of the AP in the first MLD, the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

[0241] Optionally, the first MLD may include at least one of the following APs: the second AP, the third AP, and the fourth AP, or the first MLD may include other APs (e.g., other neighboring APs), or the first MLD may include APs corresponding to any per-STA profile element carried in the MLE, which is not limited herein.

[0242] Optionally, the first element of the AP in the first MLD is located in a Frame body of a wireless frame.

[0243] In a possible implementation, the MLE further includes a first field, and a second value of the first field indicates that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

[0244] In a possible implementation, the first AP belongs to the first MLD.

[0245] In a possible implementation, the MLE includes a common information field, and the first information is located in the common information field.

[0246] In a possible implementation, the first information is a Multilink Device Identifier (MLD ID) field.

[0247] Optionally, the first information may alternatively be another field name, for example, a multilink identifier, a multilink device index, or a multilink index.

[0248] In a possible implementation, the radio frame further comprises a fragmentation element adjacent to the MLE, the MLE carrying a first part of the information of the first MLD and the fragmentation element carrying a second part of the information of the first MLD.

[0249] Optionally, the number of information elements contained in the fragment element is 1, the fragment element includes a length field, and the value of the length field is 255 or less.

[0250] Optionally, the fragment element includes n information elements, where the value of the length field of each of the n information elements except for the last information element is 255, where n is an integer greater than 1.

[0251] In a possible implementation, the radio frame is a MultiLink Probe Response frame.

[0252] It should be noted that the communication device 1500 may be further configured to implement other embodiments above and achieve corresponding beneficial effects. For details, please refer to the descriptions in the above embodiments. The details will not be described again here.

[0253] 16 is a schematic diagram of a structure of a communication device 1600 according to an embodiment of this application. The communication device 1600 includes: a processor 1601 and a transceiver 1602.

[0254] The communication device 1600 may be a wireless frame transmitting device, a wireless frame receiving device, or a chip within the wireless frame transmitting device or the wireless frame receiving device.

[0255] 16 shows only the main components of a communications device 1600. In addition to the processor 1601 and the transceiver 1602, the communications device may further include a memory 1603 and input / output devices (not shown).

[0256] The processor 1601 is mainly configured to process communication protocols and communication data, control the entire communication device, execute software programs, and process data of the software programs. The memory 1603 is mainly configured to store software programs and data. The transceiver 1602 may include a radio frequency circuit and an antenna. The radio frequency circuit is mainly configured to perform conversion between baseband signals and radio frequency signals, and process the radio frequency signals. The antenna is mainly configured to receive and transmit the radio frequency signals in the form of electromagnetic waves. The input / output device, such as a touch screen, a display, or a keyboard, is mainly configured to receive data input by a user and output data to a user.

[0257] The processor 1601, the transceiver 1602 and the memory 1603 may be connected via a communication bus.

[0258] After the communication device is powered on, the processor 1601 may read the software program from the memory 1603, interpret and execute the instructions of the software program, and process data of the software program. When data needs to be transmitted wirelessly, the processor 1601 performs baseband processing on the data to be transmitted, and then outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal, and then transmits the radio frequency signal in the form of electromagnetic waves through an antenna. When data is transmitted to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 1601. The processor 1601 converts the baseband signal into data for processing.

[0259] In any one of the above designs, the processor 1601 may include a communication interface for implementing the receiving and transmitting functions. For example, the communication interface may be a transceiver circuit, an interface, or an interface circuit. The transceiver circuit, the interface, or the interface circuit for implementing the receiving and transmitting functions may be separate or integrated together. The transceiver circuit, the interface, or the interface circuit may be configured to read and write code / data, or may be configured to transmit or forward a signal.

[0260] In any one of the above designs, the processor 1601 may store instructions. The instructions may be computer programs. The computer programs execute on the processor 1601, thereby enabling the communication device 1600 to perform the methods described in the above method embodiments. The computer programs may be fixed to the processor 1601. In this case, the processor 1601 may be implemented in hardware.

[0261] In an implementation, the communication device 1600 may include circuitry for implementing the transmitting, receiving or communicating functions of any one of the embodiments of the above method. The processor and communication interface described in this application may be implemented in an integrated circuit (IC), an analog IC, a radio frequency integrated circuit (RFIC), a mixed signal IC, an application-specific integrated circuit (ASIC), a printed circuit board (PCB), an electronic device, etc. The processor and communication interface may be fabricated using various IC technologies, such as complementary metal oxide semiconductor (CMOS), N-channel metal-oxide-semiconductor (NMOS), P-channel metal-oxide semiconductor (PMOS), bipolar junction transistor (BJT), bipolar CMOS (BiCMOS), silicon germanium (SiGe) and gallium arsenide (GaAs).

[0262] In other implementations, the radio frequency circuitry and antenna may be located separately from the processor for baseband processing, e.g., in a distributed scenario, the radio frequency circuitry and antenna may be located separately from the communication device.

[0263] The communication device may be a separate device or may be part of a larger device. For example, the communication device may be: (1) An independent integrated circuit IC, chip, or chip system or subsystem; (2) a set including one or more ICs, optionally the set of ICs may further include a storage component for storing data and instructions; (3) ASIC, e.g., modem, (4) A module that can be incorporated into other devices; (5) Receivers, intelligent terminals, wireless devices, handheld devices, mobile units, vehicle-mounted devices, cloud devices, artificial intelligence devices, or (6) Other devices, etc. That's fine too.

[0264] In the implementation process, the processor 1601 may be configured to perform, for example, but not limited to, baseband-related processing, and the transceiver 1602 may be configured to perform, for example, but not limited to, radio frequency reception and transmission. The above components may be separately located on chips independent of each other, or at least some or all of the components may be located on the same chip. For example, the processor may be further divided into an analog baseband processor and a digital baseband processor. The analog baseband processor and the transceiver may be integrated on the same chip, and the digital baseband processor may be independently located on the chip. With the continuous development of integrated circuit technology, more components may be integrated on the same chip. For example, the digital baseband processor may be integrated on the same chip as multiple application processors (for example, but not limited to, the geometric processor and the multimedia processor). Such a chip may be called a system on chip. Whether the components are independently located on different chips or integrated on one or more chips usually depends on the specific requirements of the product design. The specific implementation form of the above components is not limited in this embodiment of the present invention.

[0265] An embodiment of this application further provides a computer-readable storage medium, which stores a computer program code, and when a processor executes the computer program code, the electronic device performs the method in any one of the above embodiments.

[0266] An embodiment of this application further provides a computer program product, which, when executed on a computer, enables the computer to perform the method in any one of the above embodiments.

[0267] An embodiment of this application further provides a communication device. The device may exist in the product form of a chip. The structure of the device includes a processor and an interface circuit. The processor is configured to communicate with other devices through the interface circuit, enabling the device to perform the method in any one of the above embodiments.

[0268] An embodiment of the present application further provides a WLAN communication system, including a wireless frame transmitting device and a wireless frame receiving device, which may implement the method in any one of the above embodiments.

[0269] The steps of the method or algorithm described in conjunction with the contents disclosed in this application may be implemented by hardware or by a processor by executing software instructions. The software instructions may include corresponding software modules. The software modules may be stored in a Random Access Memory (RAM), a flash memory, an Erasable Programmable Read Only Memory (EPROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), a register, a hard disk, a removable hard disk, a Compact Disk Read Only Memory (CD-ROM), or any other form of storage medium known in the art. For example, the storage medium is coupled to the processor, such that the processor can read information from the storage medium and write information to the storage medium. Obviously, the storage medium may be part of the processor. The processor and the storage medium may be located in an ASIC. Furthermore, the ASIC may be located in the core network interface device. Obviously, the processor and the storage medium may exist as discrete components in the core network interface device.

[0270] Those skilled in the art should recognize that in one or more of the above examples, the functions described in this application may be implemented in hardware, software, firmware, or any combination thereof. When the functions are implemented in software, the functions may be stored on or transmitted as one or more instructions or codes in a computer-readable medium. Computer-readable media includes computer-readable storage media and communication media, and communication media includes any medium that facilitates the transfer of a computer program from one place to another. Storage media may be any available medium accessible to a general-purpose or special-purpose computer.

[0271] Although this application has been described with reference to embodiments, in the process of implementing this application for which protection is claimed, those skilled in the art may understand and realize other variations of the disclosed embodiments by studying the accompanying drawings, the disclosure, and the appended claims. In the claims, "comprising" does not exclude other components or steps, and "a" or "one" does not exclude a plurality. A single processor or other unit may implement several functions recited in the claims. Although some means are recited in mutually different dependent claims, this does not mean that these means cannot be combined to produce better effects.

[0272] The objectives, technical solutions and beneficial effects of this application are further described in detail in the above specific implementation manner. It should be understood that the above description is merely a specific implementation manner of this application, and is not intended to limit the protection scope of this application. Any modifications, equivalent replacements or improvements made based on the technical solutions of this application shall fall within the protection scope of this application.

Claims

1. 1. A radio frame transmission method, comprising: generating a radio frame by a first access point AP, the radio frame including a multilink element MLE, the MLE carrying information of a first multilink device MLD, the MLE including a multilink device identifier MLD ID field, the MLD ID field identifying the first MLD, the first AP not belonging to the first MLD, the first MLD being an MLD in which a second AP is located that is in the same BSSID set as the first AP; transmitting the wireless frame by the first AP; The method includes:

2. A radio frame receiving method, comprising the steps of: receiving a radio frame from a first access point AP, the radio frame including a multilink element MLE, the MLE carrying information of a first multilink device MLD, the MLE including a multilink device identifier MLD ID field, the MLD ID field identifying the first MLD, the first AP does not belong to the first MLD, the first MLD being an MLD in which a second AP is located that is in the same BSSID set as the first AP; obtaining the information of the first MLD from the MLE based on the MLD ID field; The method includes:

3. 3. The method according to claim 1, wherein the wireless frame further includes a multi-BSSID element, the multi-BSSID element includes index information of a BSSID of the second AP, and a value of the index information of the BSSID of the second AP is the same as a value of the MLD ID field.

4. The MLE includes a first per-STA profile element, the first per-STA profile element carries information of a third AP, the third AP belonging to the first MLD; 4. The method of claim 3, wherein when the first per-STA profile element does not include the first element of the third AP, the value of the first element of the third AP is the same as the value of the first element of the second AP.

5. 5. The method of claim 4, wherein the MLE further includes a first field, a first value of the first field indicating that the value of the first element of the third AP is the same as the value of the first element of the second AP.

6. the first field is located in a multilink control field within the MLE; or The method of claim 5 , wherein the first field is located in a common information field within the MLE.

7. The method according to claim 4 , wherein the value of the first element of the second AP is the same as the value of the first element of the first AP.

8. the first MLD includes a fourth AP; The method of claim 1 or 2, wherein the radio frame further includes a reduced neighboring report (RNR) element, the RNR element including information of the fourth AP and including second information for identifying the first MLD, the value of the second information being the same as the value of the MLD ID field.

9. The MLE includes a second per-STA profile element, the second per-STA profile element conveying information of an AP in the first MLD; 9. The method of claim 1, wherein when the second per-STA profile element does not include a first element of the AP in the first MLD, a value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

10. 10. The method of claim 9, wherein the MLE further includes a first field, and a second value of the first field indicates that the value of the first element of the AP in the first MLD is the same as the value of the first element of the first AP.

11. The method according to claim 1 , wherein the MLE comprises a common information field, and the MLD ID field is located in the common information field.

12. The radio frame further includes a fragment element adjacent to the MLE, 12. The method of claim 1, wherein the MLE carries a first part of the information of the first MLD and the fragment element carries a second part of the information of the first MLD.

13. The method of claim 1 , wherein the radio frame is a multilink probe response frame.

14. A wireless frame transmitting device, An apparatus comprising a transceiver unit and a processing unit, the apparatus being configured to perform the method according to claim 1 and any one of claims 3 to 13.

15. A wireless frame receiving device, An apparatus comprising a transceiver unit and a processing unit, the apparatus being configured to perform the method according to any one of claims 2 to 13.

16. An access point (AP) multi-link device (MLD) including the wireless frame transmitting apparatus according to claim 14.

17. A non-access point (non-AP) multi-link device (MLD) including the wireless frame receiving apparatus according to claim 15.

18. 1. A communications device comprising at least one processor coupled to a memory, the memory is configured to store programs or instructions; Apparatus, wherein said at least one processor is configured to execute said program or said instructions, thereby causing said apparatus to implement a method according to any one of claims 1 to 13.

19. A program, A program, when said program is executed on a computer, enabling said computer to carry out the method according to any one of claims 1 to 13.

20. 1. A computer-readable storage medium, comprising: The computer-readable storage medium stores program instructions; A computer readable storage medium, the program instructions of which, when executed, perform the method of any one of claims 1 to 13.

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