A communication method and related device suitable for multi-link

Abstract

The embodiment of the application discloses a communication method suitable for multiple links and related equipment, and the method comprises the following steps: a first multi-link device and a second multi-link device perform target wake time (TWT) negotiation, the TWT is applied to one or more links, a TWT element used for the TWT negotiation comprises a control field, the control field comprises a negotiation type field, the negotiation type field is a single-user TWT type or a broadcast TWT type, and other links are in a sleep state or a closed state. By adopting the embodiment of the application, power saving is realized.

Description

[0001] This application is a divisional application. The application number of the original application is 201910455575.5, and the original application date is May 25, 2019. The entire content of the original application is incorporated into this application by reference. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method and related equipment applicable to multiple links. Background Art

[0003] In order to significantly improve the service transmission rate of the wireless local access network (WLAN) system, the Institute of Electrical and Electronics Engineers (IEEE) 802.11ax standard further adopts orthogonal frequency division multiple access (OFDMA) technology on the basis of the existing orthogonal frequency division multiplexing (OFDM) technology. Among them, OFDMA technology supports multiple nodes to send and receive data at the same time, thereby achieving multi-site diversity gain. The 802.11ax standard and the standards before 802.11ax configure multiple links for wireless fidelity (WiFi) in the same working frequency band, but a different basic service set (BSS) is established in each link. At a time, only one link can communicate with the sites in the BSS to which the link belongs, affecting communication efficiency. Summary of the Invention

[0004] The embodiments of the present application provide a communication method and related equipment applicable to multiple links, which can improve communication efficiency.

[0005] In a first aspect, an embodiment of the present application provides a communication method applicable to multiple links, comprising: a first device sending an ADDBA request frame to a second device, the ADDBA request frame including a reference value for at least one first buffer size field and a reference value for a second buffer size field; the first device and the second device being multi-link entities comprising one or more links; the first device receiving an ADDBA response frame sent by the second device, the ADDBA response frame including a confirmation value for at least one first buffer size field and a confirmation value for the second buffer size field; establishing a multi-link block acknowledgment dialogue between the multiple links of the first device and the multiple links of the second device based on the ADDBA request frame and the ADDBA response frame; wherein a first buffer size field is used to indicate the size of a local buffer space corresponding to one of the multiple links of the first device and the second device, and the second buffer size field is used to indicate the size of a global buffer space maintained by the first device and the second device. The ADDBA request frame and the ADDBA response frame are used to negotiate the size of a global buffer space and the sizes of multiple local buffer spaces, establish a multi-link block acknowledgment dialogue, and implement communication on multiple links through the multi-link block acknowledgment dialogue.

[0006] In one possible design, based on ADDBA request frames and ADDBA response frames, the first device maintains multiple first sending windows and one second sending window, where the multiple first sending windows correspond to multiple links of the first device, and the second sending window corresponds to a multilink entity of the first device. The sending windows are used to manage and control the transmission of data packets, allowing data packets to be sent on multiple links.

[0007] In another possible design, a first send window corresponds to one of the multiple links. The first send window has a starting sequence number of WinStartO1, an ending sequence number of WinEndO1, and a window size of WinSizeO1, where WinSizeO1 is equal to the confirmed value of the first buffer size field corresponding to the link. A second send window has a starting sequence number of WinStartO2, an ending sequence number of WinEndO2, and a window size of WinSizeO2, where WinSizeO2 is equal to the confirmed value of the second buffer size negotiated via the ADDBA request and ADDBA response frames. The send window size, starting sequence number, and ending sequence number ensure packet delivery.

[0008] In another possible design, the ADDBA request frame includes a first block confirmation start sequence number control field and a second block confirmation start sequence number control field. The first block confirmation start sequence number control field is used to indicate the first initial sequence number of the start sequence number of the first scoreboard of the link of the second device, and can also be used to indicate the first initial sequence number of the start sequence number of the first receive window of the link of the second device. The type of the first initial sequence number is a local sequence number; the second block confirmation start sequence number control field is used to indicate the second initial sequence number of the start sequence number of the second scoreboard of the multi-link entity of the second device, and can also be used to indicate the first initial sequence number of the start sequence number of the second receive window of the link of the second device. The type of the second initial sequence number is a global sequence number. The first initial sequence number is used to instruct the low MAC layer of the second device to maintain a scoreboard or receive window, and the second initial sequence number is used to instruct the high MAC layer of the second device to maintain a scoreboard or receive window.

[0009] In another possible design, the ADDBA request frame includes at least one of a link bitmap field and a reference value of at least one first buffer size field, or at least one of a link number field, a plurality of link identification number fields, and a reference value of at least one first buffer size field; and the ADDBA response frame includes at least one of a link bitmap field and a confirmation value of at least one first buffer size field, or at least one of a link number field, a plurality of link identification number fields, and a confirmation value of at least one first buffer size field. The first buffer size is negotiated through the ADDBA request frame and the ADDBA response frame to ensure that the local buffer space of each link of the first device and the second device has the same size.

[0010] In another possible design, the ADDBA request frame includes a first block confirmation parameter set field, which includes a reference value for the second buffer size field; and the ADDBA response frame includes a second block confirmation parameter set field, which includes a confirmation value for the second buffer size. The second buffer size is negotiated through the ADDBA request frame and the ADDBA response frame to ensure that the global buffer space of the multilink entities of the first device and the second device are of the same size.

[0011] In another possible design, a first device sends a data packet to a second device and receives an acknowledgment message from the second device regarding the response data packet. The data packet includes a local sequence number and a global sequence number. The local sequence number is assigned to the data packet by the link that transmits the data packet, while the global sequence number is assigned to the data packet by the multi-link entity. Using the local and global sequence numbers, the first device can correctly send data packets of the same type across multiple links, thereby improving communication efficiency.

[0012] In another possible design, a first device sends a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame to a second device. The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame includes a starting sequence number control field, which includes a starting sequence number. The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame also includes first indication information, which is used to indicate a type of the starting sequence number, which includes a local sequence number or a global sequence number. Thus, the second device can confirm receipt of the data packet based on the type of the starting sequence number and generate a block acknowledgment bitmap corresponding to the local sequence number or a block acknowledgment bitmap corresponding to the global sequence number.

[0013] In another possible design, the first device receives a block confirmation frame sent by the second device, the block confirmation frame includes a starting sequence number control field, the starting sequence number control field includes a starting sequence number and a block confirmation bit map; the block confirmation bit map is used to indicate the reception status of the data packet received by the second device; the block confirmation frame also includes a block confirmation BA control field, the BA control field includes second indication information, the second indication information is used to indicate the type of the starting sequence number, the type of the starting sequence number is a local sequence number or a global sequence number, and the first bit in the block confirmation bit map corresponds to the starting sequence number.

[0014] In another possible design, both the ADDBA request frame and the ADDBA response frame include a block acknowledgment function field, which includes information indicating the function type of a multi-link block acknowledgment session. The function types of a multi-link block acknowledgment session include: multi-link block acknowledgment request, multi-link block acknowledgment response, and multi-link block acknowledgment session teardown. The information in the ADDBA request frame indicates that the multi-link block acknowledgment session is a multi-link block acknowledgment request, and the information in the ADDBA response frame indicates that the multi-link block acknowledgment session is a multi-link block acknowledgment response. The multi-link block acknowledgment session function is added through negotiation of the ADDBA request frame and the ADDBA response frame to ensure successful establishment of the multi-link block acknowledgment session.

[0015] In a second aspect, an embodiment of the present application provides a communication method applicable to multiple links, comprising: a second device receiving an ADDBA request frame sent by a first device, the ADDBA request frame including a reference value for at least one first buffer size field and a reference value for a second buffer size field; the first device and the second device being multi-link entities comprising one or more links; the second device sending an ADDBA response frame to the first device, the ADDBA response frame including a confirmation value for at least one first buffer size field and a confirmation value for the second buffer size field; and establishing a multi-link block acknowledgment dialogue between the multiple links of the first device and the multiple links of the second device based on the ADDBA request frame and the ADDBA response frame, wherein a first buffer size field is used to indicate the size of a local buffer space corresponding to one of the multiple links of the first device and the second device, and the second buffer size field is used to indicate the size of a global buffer space maintained by the first device and the second device. The size of a global buffer space and the sizes of multiple local buffer spaces are negotiated through the ADDBA request frame and the ADDBA response frame, thereby establishing a multi-link block acknowledgment dialogue, and enabling communication over the multiple links through the multi-link block acknowledgment dialogue.

[0016] In one possible design, the second device maintains a receive window based on ADDBA request and response frames. The receive window corresponds to the link entity of the second device. The receive window has a starting sequence number of WinStartB2, an ending sequence number of WinEndB2, and a window size of WinSizeB2, where WinSizeB2 is equal to the smaller of the confirmation value of the second buffer size field and the maximum length block confirmation bitmap. The send window manages and controls the transmission of data packets, allowing them to be sent across multiple links, thereby improving communication efficiency.

[0017] In another possible design, based on the ADDBA request frame and the ADDBA response frame, the second device maintains multiple first receive windows and one second receive window, where the multiple first receive windows correspond to multiple links of the second device, and the second receive window corresponds to a link entity of the second device. The sending of data packets is managed and controlled by the send window, allowing data packets to be sent over multiple links, thereby improving communication efficiency.

[0018] In another possible design, a first receive window corresponds to one of the multiple links. The first receive window has a starting sequence number of WinStartB1, an ending sequence number of WinEndB1, and a window size of WinSizeB1, where WinSizeB1 is equal to the smaller of the confirmation value of the first buffer size field corresponding to the link and the maximum length block confirmation bitmap. A second receive window has a starting sequence number of WinStartB2, an ending sequence number of WinEndB2, and a window size of WinSizeB2, where WinSizeB2 is equal to the smaller of the confirmation value of the second buffer size and the maximum length block confirmation bitmap. Received data packets are reordered based on the receive window size, starting sequence number, and ending sequence number.

[0019] In another possible design, the ADDBA request frame includes a first block confirmation starting sequence number control field and a second block confirmation starting sequence number control field. The first block confirmation starting sequence number control field is used to indicate the first initial sequence number of the starting sequence number of the first scoreboard of the link of the second device, and can also be used to indicate the first initial sequence number of the starting sequence number of the first receiving window of the link of the second device. The type of the first initial sequence number is a local sequence number. The second block confirmation starting sequence number control field is used to indicate the second initial sequence number of the starting sequence number of the second scoreboard of the multi-link entity of the second device, and can also be used to indicate the first initial sequence number of the starting sequence number of the second receiving window of the link of the second device. The type of the second initial sequence number is a global sequence number. The first initial sequence number is used to instruct the low MAC layer of the second device to maintain a scoreboard or receiving window, and the second initial sequence number is used to instruct the high MAC layer of the second device to maintain a scoreboard or receiving window.

[0020] In another possible design, the ADDBA request frame includes at least one of a link bitmap field and a reference value of at least one first buffer size field, or at least one of a link number field, a plurality of link identity number field, and a reference value of at least one first buffer size field; and the ADDBA response frame includes at least one of a link bitmap field and a confirmation value of at least one first buffer size field, or at least one of a link number field, a plurality of link identity number field, and a confirmation value of at least one first buffer size field. The first buffer size is negotiated through the ADDBA request frame and the ADDBA response frame to ensure that the size of the local buffer space of each link of the first device and the second device is the same. The first buffer size is negotiated through the ADDBA request frame and the ADDBA response frame to ensure that the size of the local buffer space of each link of the first device and the second device is the same.

[0021] In another possible design, the ADDBA request frame includes a first block acknowledgement parameter set field, and the first block acknowledgement parameter set field includes a reference value of the second buffer size field; the ADDBA response frame includes a second block acknowledgement parameter set field, and the second block acknowledgement parameter set field includes a confirmation value of the second buffer size. The second buffer size is negotiated through the ADDBA request frame and the ADDBA response frame, so as to ensure that the global buffer space of the multi-link entity of the first device and the second device has the same size.

[0022] In another possible design, the second device receives a data packet sent by the first device, and sends an acknowledgement message for responding to the data packet to the first device. The data packet includes a local sequence number and a global sequence number, the local sequence number is an identifier assigned to the data packet by a link in the plurality of links, and the global sequence number is an identifier assigned to the data packet by the multi-link entity. Through the local sequence number and the global sequence number, the second device can correctly receive the same type of data packet on the plurality of links, so as to improve the communication efficiency.

[0023] In another possible design, the second device receives a block acknowledgement request frame or a multi-user block acknowledgement request trigger frame sent by the first device, the block acknowledgement request frame or the multi-user block acknowledgement request trigger frame includes a starting sequence number control field, and the starting sequence number control field includes a starting sequence number; the block acknowledgement request frame or the multi-user block acknowledgement request trigger frame further includes first indication information, and the first indication information is used to indicate the type of the starting sequence number, and the type of the starting sequence number includes the local sequence number or the global sequence number. Therefore, the second device can confirm the received data packet through the type of the starting sequence number, and generate a block acknowledgement bitmap corresponding to the local sequence number or a block acknowledgement bitmap corresponding to the global sequence number.

[0024] In another possible design, the second device maintains a plurality of first scoreboards and a second scoreboard, the plurality of first scoreboards correspond to the plurality of links, and the second scoreboard corresponds to the multi-link entity; a starting sequence number of a first scoreboard is WinStartR1, an ending sequence number of the first scoreboard is WinEndR1, and a size of the first scoreboard is WinSizeR1, where WinSizeR1 is equal to a smaller value between a confirmation value of a first buffer size field corresponding to a link corresponding to the first scoreboard and a block acknowledgement bitmap of a maximum length; a starting sequence number of the second scoreboard is WinStartR2, an ending sequence number of the second scoreboard is WinEndR2, and a size of the second scoreboard is WinSizeR2, where WinSizeR2 is equal to a smaller value between a confirmation value of a second buffer size and a block acknowledgement bitmap of a maximum length. Through maintaining the plurality of first scoreboards and the second scoreboard, the second device can correctly confirm the received data packet.

[0025] In another possible design, the acknowledgment message is a block acknowledgment frame; the block acknowledgment frame includes a starting sequence number control field, which includes a starting sequence number and a block acknowledgment bitmap; the block acknowledgment bitmap is used to indicate a reception status of a data packet received by the second device. The block acknowledgment frame also includes a block acknowledgment BA control field, which includes second indication information, which is used to indicate a type of the starting sequence number, where the type of the starting sequence number is either a local sequence number or a global sequence number, and the first bit in the block acknowledgment bitmap corresponds to the starting sequence number.

[0026] In another possible design, if the sequence corresponding to the block confirmation bit map is a local sequence number, the sequence number corresponding to the first bit in the block confirmation bit map is WinStartR1; if the sequence corresponding to the block confirmation bit map is a global sequence number, the sequence number corresponding to the first bit in the block confirmation bit map is WinStartR2.

[0027] In another possible design, both the ADDBA request frame and the ADDBA response frame include a block acknowledgment function field, which includes information indicating the function type of a multi-link block acknowledgment session. The function types of a multi-link block acknowledgment session include: multi-link block acknowledgment request, multi-link block acknowledgment response, and multi-link block acknowledgment session teardown. The information in the ADDBA request frame indicates that the multi-link block acknowledgment session is a multi-link block acknowledgment request, and the information in the ADDBA response frame indicates that the multi-link block acknowledgment session is a multi-link block acknowledgment response. The multi-link block acknowledgment session function is added through negotiation of the ADDBA request frame and the ADDBA response frame to ensure successful establishment of the multi-link block acknowledgment session.

[0028] In a third aspect, an embodiment of the present application provides a data frame transmission method, comprising: a first device sending a message frame to a second device, the message frame including first indication information, the first indication information being used to indicate a main link among multiple links. Second indication information is sent to the second device via the main link, the second indication information indicating the working status or sleep status of the multiple links, or TWT negotiation is performed with the second device via the main link, so that other links are in a sleep state or a closed state, thereby achieving power saving.

[0029] In one possible design, the first indication information is a special element. The first device may send a message frame to the second device via a primary link. The message frame may carry a special element, which is carried only in message frames sent via the primary link. The special element is used to indicate that the link transmitting the message frame is the primary link. Indicating the primary link by the special element causes other links to be dormant or shut down, thereby saving power.

[0030] In another possible design, the first indication information is a link sequence number. The first device may send a message frame to the second device via a non-primary link. The message frame may carry an abbreviated neighbor report element or a multi-band element. The abbreviated neighbor report element or the multi-band element includes a link sequence number, which is used to indicate a primary link among multiple links. Indicating the primary link by the link sequence number causes other links to be dormant or disabled, thereby saving power.

[0031] In another possible design, an operation type field is added to the information field of the single-user TWT parameter or the information field of the broadcast TWT parameter, and the operation type field and the TWT channel field are combined to indicate to which link among multiple links the TWT element is applied. An indication value can be added to the broadcast TWT parameter information field, and the indication value is used to indicate to which link among multiple links the TWT element is applied. This enables operation within the service window indicated by the TWT parameter, and sleep outside the service window, thereby saving power.

[0032] In another possible design, one or more link sequence numbers are added to the information field of the single-user TWT parameter and the information field of the broadcast TWT parameter, and the link sequence number is used to indicate on which link among the multiple links the TWT element is applied. Alternatively, a link sequence number bit map is used to indicate on which link among the multiple links the TWT element is applied. This allows the system to work within the service window indicated by the TWT parameter and sleep outside the service window, thereby saving power.

[0033] In a fourth aspect, an embodiment of the present application provides a data frame transmission method, comprising: a second device receives a message frame sent by a first device, the message frame including first indication information, and the first indication information is used to indicate a main link among multiple links. The second device receives second indication information sent by the first device through the main link, the second indication information indicating the working status or sleep status of the multiple links, or performs TWT negotiation with the first device through the main link, so that other links are in a sleep state or a closed state, thereby saving power.

[0034] In one possible design, the first indication information is a special element. The second device may receive a message frame sent by the first device via a primary link. The message frame may carry a special element, which is carried only in message frames sent via the primary link. The special element is used to indicate that the link transmitting the message frame is the primary link. Indicating the primary link by the special element causes other links to be dormant or shut down, thereby saving power.

[0035] In another possible design, the first indication information is a link sequence number. The second device may receive a message frame sent by the first device via a non-primary link. The message frame may carry an abbreviated neighbor report element or a multi-band element. The abbreviated neighbor report element or the multi-band element includes a link sequence number, which is used to indicate a primary link among multiple links. Indicating the primary link by the link sequence number causes other links to be dormant or disabled, thereby saving power.

[0036] In the fifth aspect, an embodiment of the present application provides a first communication device, which is configured to implement the methods and functions performed by the first device in the above-mentioned first and third aspects, and is implemented by hardware / software, and its hardware / software includes modules corresponding to the above-mentioned functions.

[0037] In the sixth aspect, an embodiment of the present application provides a second communication device, which is configured to implement the methods and functions performed by the second device in the above-mentioned second and fourth aspects, and is implemented by hardware / software, and its hardware / software includes modules corresponding to the above-mentioned functions.

[0038] In the seventh aspect, an embodiment of the present application provides another first device, including: a processor, a memory and a communication bus, wherein the communication bus is used to realize connection and communication between the processor and the memory, and the processor executes the program stored in the memory to implement the steps of the above-mentioned first and third aspects.

[0039] In one possible design, the first device provided in this application may include a module for executing the behavior corresponding to the first entity in the above method design. The module may be software and / or hardware.

[0040] In the eighth aspect, an embodiment of the present application provides another second device, including: a processor, a memory and a communication bus, wherein the communication bus is used to realize connection and communication between the processor and the memory, and the processor executes the program stored in the memory to implement the steps provided in the above-mentioned second and fourth aspects.

[0041] In one possible design, the second device provided in this application may include a module for executing the behavior corresponding to the first device in the above method design. The module may be software and / or hardware.

[0042] In a ninth aspect, the present application provides a computer-readable storage medium, in which instructions are stored. When the computer-readable storage medium is run on a computer, the computer executes the methods in the above aspects.

[0043] In a tenth aspect, the present application provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute the methods in the above aspects.

[0044] In an eleventh aspect, a chip is provided, comprising a processor for calling and executing instructions stored in a memory from the memory, so that a communication device equipped with the chip executes the method of any one of the above aspects.

[0045] In the twelfth aspect, the embodiments of the present application also provide another chip, which can be a chip in the first device or the second device, and the chip includes: an input interface, an output interface and a processing circuit, and the input interface, the output interface and the circuit are connected through an internal connection path, and the processing circuit is used to execute any of the methods above.

[0046] In the thirteenth aspect, another chip is provided, comprising: an input interface, an output interface, a processor, and optionally, a memory, wherein the input interface, the output interface, the processor and the memory are connected via an internal connection path, and the processor is used to execute the code in the memory. When the code is executed, the processor is used to execute the method in any of the above aspects.

[0047] In a fourteenth aspect, a device is provided for implementing the method of any of the above aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0049] Figure 1 is a schematic diagram of a multi-band operation provided by an embodiment of the present application;

[0050] Figure 2 This is a schematic diagram of the architecture of a multi-band hardware provided in an embodiment of the present application;

[0051] Figure 3 This is a schematic diagram of the architecture of a communication system provided by an embodiment of the present application;

[0052] Figure 4 This is a schematic diagram of the structure of an AP and a STA provided in an embodiment of the present application;

[0053] Figure 5 This is a schematic diagram of another structure of an AP and a STA provided in an embodiment of the present application;

[0054] Figure 6 This is a flow chart of a multi-link communication method provided in an embodiment of the present application;

[0055] Figure 7 Schematic diagram of an ADDBA request frame provided in an embodiment of the present application;

[0056] Figure 8This is a schematic diagram of a block confirmation function field provided by an embodiment of the present application;

[0057] Figure 9 This is a schematic diagram of a block confirmation parameter set field provided by an embodiment of the present application;

[0058] Figure 10 is a schematic diagram of a multi-link element provided in an embodiment of the present application;

[0059] Figure 11 This is a schematic structural diagram of a first device transmitting end provided in an embodiment of the present application;

[0060] Figure 12 This is a schematic structural diagram of a second device receiving end provided in an embodiment of the present application;

[0061] Figure 13 Schematic diagram of an ADDBA response frame provided in an embodiment of the present application;

[0062] Figure 14 A schematic diagram of a MAC header provided in an embodiment of the present application;

[0063] Figure 15 This is a schematic diagram of a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame provided in an embodiment of the present application;

[0064] Figure 16 A schematic diagram of a block confirmation frame provided in an embodiment of the present application;

[0065] Figure 17 This is a flow chart of a data frame transmission method provided in an embodiment of the present application;

[0066] Figure 18 This is a schematic diagram of a TWT element for TWT negotiation provided in an embodiment of the present application;

[0067] Figure 19 This is a schematic diagram of a single-user TWT type provided in an embodiment of the present application;

[0068] Figure 20 This is a schematic diagram of a broadcast TWT type provided in an embodiment of the present application;

[0069] Figure 21 is a structural diagram of a first communication device provided in an embodiment of the present application;

[0070] Figure 22 is a structural diagram of a second communication device provided in an embodiment of the present application;

[0071] Figure 23 is a structural diagram of another first device proposed in an embodiment of the present application;

[0072] Figure 24 This is a structural diagram of another second device proposed in an embodiment of the present application. DETAILED DESCRIPTION

[0073] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0074] The US Federal Communications Commission (FCC) has opened a new free frequency band, 5925-7125 MHz, hereafter referred to as the 6 GHz band. Consequently, 802.11ax standards developers expanded the operating range of 802.11ax devices from 2.4 GHz and 5 GHz to 2.4 GHz, 5 GHz, and 6 GHz in the 802.11ax Project Authorization Requests (PARs). However, specific standard protocols, such as the maximum supported bandwidth of 160 Mbps and the frame structure, remained unchanged.

[0075] Each generation of mainstream Wi-Fi protocols is compatible with legacy sites. For example, the frame structure of 802.11a, the earliest mainstream Wi-Fi protocol, begins with a preamble, including the legacy-short training field (L-STF), the legacy-long training field (L-LTF), and the legacy-signal field (L-SIG). The preamble of 802.11a is called the legacy preamble. The frame structures of subsequent mainstream Wi-Fi protocols, 802.11g, 802.11n, 802.11ac, and 802.11ax, all begin with the legacy preamble to ensure compatibility with legacy sites.

[0076] The extremely high throughput (EHT) device of the next generation WiFi protocol of IEEE 802.11 needs to be compatible with the 802.11ax device, and therefore supports the working frequency bands of the 802.11ax device, that is, supports the 2.4 GHz, 5 GHz and 6 GHz frequency bands. Similarly, the next generation WiFi protocol also needs to be compatible, and the frame structure starts with a traditional preamble, followed by a new generation preamble, which includes a new function indication for implementing the new generation WiFi protocol EHT, such as a bandwidth indication for a super large bandwidth. In addition, the new generation preamble also carries indication information for indicating that the physical layer protocol data unit (PPDU) is an EHT PPDU, so as not to be misjudged by the receiving end as a traditional PPDU, such as the PPDU of 802.11a, the high throughput (HT) PPDU of 802.11n, the very high throughput (VHT) PPDU of 802.11ac or the HE PPDU of 802.11ax. In addition to increasing the peak throughput through a super large bandwidth, the next generation WiFi EHT protocol of IEEE 802.11ax can also increase the peak throughput through more streams (for example, the number of streams is increased to 16 streams) and the cooperation of multiple frequency bands (for example, 2.4 GHz, 5 GHz and 6 GHz). On the same frequency band, the peak throughput can also be increased through the cooperation of multiple channels, and the delay of service transmission is reduced. Among them, the multiple frequency bands or multiple channels can be collectively referred to as multiple links.

[0077] The 802.11ax standard and the standards before 802.11ax configure multiple links in one or more working frequency bands of WiFi, but different BSSs are established in each link, and only one link can communicate with the stations in the BSS to which the link belongs at a time. In the next generation WiFi EHT protocol of IEEE 802.11, in addition to using the continuous super large bandwidth of the 6 GHz frequency band, the discontinuous multiple links can also be aggregated into a super large bandwidth through a multi-link cooperation technology. In addition to aggregating a larger bandwidth, the multi-link cooperation technology can also use the multi-link cooperation technology to simultaneously send the same type of data packet to the same station.

[0078] As shown in Figure 1 Figure 1 ​is a schematic diagram of multi-band operation provided by an embodiment of the present application. WiFi operating bands include 1GHz below, 2.4GHz and 5GHz and high frequency 60GHz, while mainstream WiFi protocols 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac and 802.11ax mainly work at 2.4GHz and 5GHz, supporting multi-band cooperation technology. Figure 1 Two-band operation is given, and each band operating unit includes a MAC processing unit (MAC unite), a baseband processing unit (base band unite, BBU), a radio frequency unit (radio frequency unite, RFU) and an antenna module (antenna module). Among them, the multi-band shares the MAC processing unit and the antenna module.

[0079] As shown in Figure 2 , Figure 2 is a schematic diagram of a multi-band hardware architecture provided by an embodiment of the present application. The multi-band hardware includes an upper media access control (media access control, MAC) layer (up MAC layer), a MAC service data unit (MAC service data unit, MSDU) parser and inverse parser, a MAC control unit (MAC control unite, MCU), a baseband processing unit (base band unite, BBU) and a radio frequency unit (radio frequency unite, RFU) and an antenna module not shown in the figure. In addition to sharing the MAC processing unit, multi-band operation also shares the upper MAC layer, the parser and the inverse parser, receives or transmits the MSDU processed by the upper MAC layer through the upper MAC layer, and then distributes the MSDU to each band through the parser and the inverse parser. Each band has an independent MCU unit, and the MCU main unit is used to encapsulate the MSDU into MPDU, that is, add a MAC header in front of the MSDU.

[0080] At present, the mainstream WiFi multi-band operation is to form an independent BSS on each frequency band, and each BSS independently manages different sites without interfering with each other. 802.11ad on the high frequency 60GHz introduces FST, which can include non-transparent FST and transparent FST. The main difference between non-transparent FST and transparent FST is that the former uses different MAC addresses for sites in different frequency bands, while the latter uses the same MAC address for sites in different frequency bands. FST technology can transfer all services or a certain type of service of a site from one frequency band to another for transmission, where the services are distinguished by service type (traffic identifier, TID). In addition, FST conversations can occur in one frequency band, or from one channel in the same frequency band to another channel, or simultaneously occur in multiple frequency bands and / or multiple channels. However, when transferring the service of a site from one frequency band to another for transmission, only one of the frequency bands can be used for transmission at a certain time, and it does not consider using multiple frequency bands to transmit the same type of service to a certain site at the same time, which affects communication efficiency. In order to solve the above technical problems, the embodiments of the present application provide the following solutions.

[0081] like Figure 3 As shown, Figure 3 It is an architectural diagram of a communication system provided by an embodiment of the present application. The communication system may include an access point (AP) and multiple stations (STA). The embodiment of the present application can be applicable to data communication between an AP and one or more STAs, and is also applicable to data communication between APs and APs, or data communication between STAs and STAs. The AP can be used as the first device mentioned in this application, or as the second device mentioned in this application. The STA can be used as the first device mentioned in this application, or as the second device mentioned in this application. In the WLAN system 802.11ax after the introduction of OFDMA technology, the AP can perform uplink and downlink transmissions with different STAs on different time-frequency resources. The AP can adopt different modes for uplink and downlink transmissions, such as OFDMA single-user multiple-input multiple-output (SU-MIMO) mode, or OFDMA multi-user multiple-input multiple-output (MU-MIMO).

[0082] An AP is an access point for mobile users to access wired networks. It is primarily deployed in homes, buildings, and campuses, with a typical coverage radius of tens to hundreds of meters. It can also be deployed outdoors. An AP acts as a bridge between wired and wireless networks, connecting wireless network clients and integrating the wireless network into the Ethernet network. Specifically, an AP can be a terminal device or network device equipped with a WiFi chip. An AP can support the 802.11ax standard. It can also support various WLAN standards, such as 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a. A STA can be a wireless communication chip, wireless sensor, or wireless communication terminal. Examples include mobile phones with WiFi communication capabilities, tablets with WiFi communication capabilities, set-top boxes with WiFi communication capabilities, smart TVs with WiFi communication capabilities, smart wearable devices with WiFi communication capabilities, in-vehicle communication devices with WiFi communication capabilities, and computers with WiFi communication capabilities. Optionally, a STA can support the 802.11ax standard. STA can also support multiple WLAN standards such as 802.11ac, 802.11n, 802.11g, 802.11b and 802.11a.

[0083] like Figure 4 As shown, Figure 4 This is a structural diagram of an AP and STA provided in an embodiment of the present application. Since the 802.11 standard only focuses on the 802.11PHY and MAC parts, the figure only shows the PHY and MAC parts of the AP and STA. The AP shown in the figure has multiple antennas, and the STA has a single antenna structure. In actual scenarios, the AP and STA can have multiple antennas and can be devices with more than two antennas. For example Figure 5 As shown, Figure 5 This is a schematic diagram of another AP and STA structure provided by an embodiment of the present application. The AP and STA have the same internal structure, which can be divided from top to bottom into the application layer module, transmission control protocol (TCP) / user datagram protocol (UDP) processing module, network protocol (IP) processing module, logical link control (LLC) module, MAC layer module, PHY baseband module, radio frequency and antenna, among which multiple antennas can be configured.

[0084] like Figure 6 As shown, Figure 6This is a flow chart of a multi-link communication method provided in an embodiment of the present application. The steps in the embodiment of the present application at least include:

[0085] In an embodiment of the present application, block acknowledgment (BA) transmission is a mechanism introduced by the IEEE 802.11e standard, which allows the first device to send multiple data packets without receiving an acknowledgment frame. The first device then sends a block acknowledgment request frame (BAR), and the second device needs to feedback a BA after receiving the BAR to confirm the series of data frames sent by the first device. Since the second device transmits the acknowledgment of multiple data packets in one BA frame, the transmission time of the acknowledgment frame can be reduced and the channel utilization rate can be improved. In order to enable the first device and the second device to use the BA transmission mechanism to send and receive data packets, the first device and the second device need to establish a multi-link BA session through the BA establishment process before sending data packets. The multi-link BA session establishment process is as follows:

[0086] S601: A first device sends an add block acknowledgment (ADDBA) request frame to a second device, and the second device receives the ADDBA request frame sent by the first device.

[0087] The ADDBA request frame includes one or more first buffer size fields and second buffer size fields, and the first buffer size fields and the second buffer size fields are used to provide reference values ​​for negotiating corresponding buffer size field values ​​with the second device. The first device may include a multi-link entity and multiple links, and the second device may also include a multi-link entity and multiple links. The multiple links of the first device correspond to the multiple links of the second device, and each link may include a lower MAC layer and a physical PHY layer.

[0088] like Figure 7 As shown, Figure 7 This is a schematic diagram of an ADDBA request frame provided in an embodiment of the present application. The ADDBA request frame may include a block confirmation function field, a block confirmation parameter set field, and a block confirmation start sequence number control field. Optionally, the second device needs to feedback an acknowledgment frame Ack after receiving the ADDBA request frame, and the first device also needs to feedback an acknowledgment frame Ack after receiving the ADDBA response frame. The acknowledgment frame Ack in the embodiment of the present application is not included in the Figure 6 It is reflected in.

[0089] The ADDBA request frame may include a block confirmation function field, and a function related to a multi-link block confirmation session may be added to the block confirmation function field of the ADDBA request frame. The block confirmation function field includes information for indicating the function type of the multi-link block confirmation session. The information in the ADDBA request frame indicates that the multi-link block confirmation session is a multi-link block confirmation request. Figure 8 As shown, Figure 8 Schematic diagram of a block confirmation function field provided by an embodiment of the present application. The block confirmation function field may include field values ​​0-255. For example, a field value of 0 indicates the function of an ADDBA request, a field value of 1 indicates the function of an ADDBA response, a field value of 2 indicates BA session deletion, and so on. The block confirmation function field also includes field values ​​3-127, 131, and 134-255. These field values ​​are reserved field values ​​and can be used to indicate the function type of a multi-link block confirmation session, such as a multi-link block confirmation request, a multi-link block confirmation response, a multi-link block confirmation session teardown, and so on.

[0090] The ADDBA request frame may include one or more first block confirmation starting sequence fields, and may also include a second block confirmation starting sequence field. The ADDBA request frame includes a block confirmation starting sequence number control field, and the block confirmation starting sequence number control field includes a 4-bit fragmentation field and a 12-bit starting sequence number field. The ADDBA request frame may also include a multi-link element. Multiple first block confirmation starting sequence control fields may be carried in the block confirmation starting sequence number control field, and the second block confirmation starting sequence field may be carried in the multi-link element. Alternatively, multiple first block confirmation starting sequence control fields may be carried in the multi-link element, and the second block confirmation starting sequence field may be carried in the block confirmation starting sequence number control field. It should be noted that the carrying locations of multiple first block confirmation starting sequence fields and second block confirmation starting sequence fields are not limited. The first block confirmation starting sequence number control field is used to indicate the first initial sequence number of the starting sequence number of the first scoreboard of the link of the second device, and may also be used to indicate the first initial sequence number of the starting sequence number of the first receiving window of the second device. The type of the first initial sequence number is a local sequence number. The first receiving window and the first scoreboard are maintained by the low MAC layer of the second device, and the first initial sequence number is used to set the initial value of the first receiving window WinStartB, which is described in detail below. The second block confirmation starting sequence number control field is used to indicate the second initial sequence number of the starting sequence number of the second scoreboard of the multi-link entity of the second device, and can also be used to indicate the second initial sequence number of the starting sequence number of the second receiving window of the second device, and the type of the second initial sequence number is a global sequence number. The second receiving window and the second scoreboard are maintained by the high MAC layer of the second device, and the second initial sequence number is used to set the initial value of the second receiving window WinStartB, which is described in detail below.

[0091] The ADDBA request frame may include a block acknowledgement parameter set field, and the block acknowledgement parameter set field includes the second buffer size field. Figure 9 As shown, Figure 9 This is a schematic diagram of a Block Acknowledgement Parameter Set field provided in an embodiment of the present application. The Block Acknowledgement Parameter Set field may include 1 bit for A-MSDU support, 2 bits for Block Acknowledgement Policy, 3 bits for Service Type, and 10 bits for Buffer Size. The 10-bit Buffer Size field may be used to indicate the size of the global buffer space. The sizes of the individual fields are not limited.

[0092] In addition, a multi-link element may be added to the ADDBA request frame, and the ADDBA request frame includes the multi-link element. Figure 10 As shown, Figure 10This is a schematic diagram of a multi-link element provided by an embodiment of the present application. The multi-link element includes an element number, a length field, and an indication field. The indication field may include the following two modes: In the first mode, the indication field may include a link bitmap field and at least one first buffer size field. The number of first buffer size fields is equal to the number of bits set to "1" in the link bitmap, and the link bitmap may indicate which links participate in the multi-link BA session. For example, if the first link participates in the establishment of a multi-link BA session, the second link does not participate in the establishment of a multi-link BA session, the third link does not participate in the establishment of a multi-link BA session, and the fourth link participates in the establishment of a multi-link BA session, the bitmap may represent 1001. In the second mode, the indication field may include a link number field, multiple link identity number fields, and at least one first buffer size field, wherein the number of link identity number fields and the number of first buffer size fields are the same as the value of the link number field, and the multiple link identity number fields are used to indicate which links participate in the establishment of a multi-link BA session. In addition, the multilink element also includes multiple first block acknowledgement start sequence control fields, where the number of first block acknowledgement start sequence control fields is equal to the number of links participating in the multilink BA session. The above-mentioned indication field is not limited to being carried in the multilink element, but can also be carried in existing fields or elements in the ADDBA request frame, such as the Multi-Band element or the ADDBA extension element.

[0093] It should be noted that one or more first buffer size fields and second buffer size fields can also be carried through other fields. For example, the first buffer size field can also be indicated by the block confirmation parameter set field, and the second buffer size field can also be indicated by the multi-link element. The two can also be indicated in other ways, which are not limited here.

[0094] Optionally, after the second device receives the ADDBA request frame sent by the first device, the second device may send an acknowledgment frame Ack to the first device in response to the ADDBA request frame, and then the first device receives the acknowledgment frame Ack sent by the second device.

[0095] S602: The second device sends an ADDBA response frame to the first device, and the first device receives the ADDBA response frame sent by the second device. The ADDBA response frame includes confirmation values ​​of the one or more first buffer size fields and confirmation values ​​of the second buffer size, where the first buffer size field and the second buffer size field serve as confirmation values ​​for establishing a block ACK session. The ADDBA request frame and the ADDBA response frame are used to establish a multi-link block ACK session between the multiple links of the first device and the multiple links of the second device.

[0096] like Figure 11 As shown, Figure 11 This is a structural diagram of a first device transmitting end provided by an embodiment of the present application. The first device includes a high MAC layer and multiple links (such as link 1 and link 2), and the link includes a low MAC layer and a PHY layer. The high MAC layer includes a global buffer space, in which a buffer queue can be maintained, and a global sequence number is assigned to each data packet. The low MAC layer may optionally include a local buffer space, or may not include a local buffer space, and assign a local sequence number to each data packet. For example Figure 12 As shown, Figure 12 1 is a structural diagram of a second device receiving end provided by an embodiment of the present application. The second device receiving end includes a high MAC layer and multiple links (such as link 1 and link 2), and the link includes a low MAC layer and a PHY layer. The low MAC layer may include a local buffer space and a first scoreboard, and the first scoreboard may be used to respond to the confirmation of the same type of data packets received by this link. The high MAC layer includes a global buffer space and a second scoreboard, and a reordering buffer queue may be maintained in the global buffer space. The second scoreboard may be used to respond to the confirmation of the same type of data packets received by the multi-link entity.

[0097] In a block confirmation dialogue, the first buffer size field is used to determine the size of the first scoreboard for link negotiation. Optionally, the first buffer size field can also be used to determine the size of the local buffer space for link negotiation. If there are n links, n first buffer size fields are required. In another embodiment, there is one first buffer size field, i.e., the size of the first scoreboard negotiated for each link is the same, and the size of the optional local buffer space is the same. The second buffer size field is used to determine the size of the second scoreboard and global buffer space negotiated by the multi-link entity. Each multi-link entity will only negotiate one second buffer size field, corresponding to the second scoreboard and global buffer space shared by the higher MAC layer.

[0098] The size of the first buffer size field can be 64, 128, or 256. If the first device has three links, the first buffer size A, first buffer size B, and first buffer size C can be increased. The size of the second buffer size field can be 1024, 2048, or 4096, etc. Usually, the size of the second buffer size field is larger than the size of the first buffer size field, but there are exceptions.

[0099] It should be noted that a multi-link entity refers to an entity that includes one or more links that share a MAC service access point (SAP). A link refers to a station with transmit and receive capabilities, such as a PHY and a MAC (such as a low MAC).

[0100] like Figure 13 As shown, Figure 13 This is a schematic diagram of an ADDBA response frame provided in an embodiment of the present application. The ADDBA response frame may include a block confirmation function field, a block confirmation parameter set field, and the like.

[0101] Among them, the related functions of the multi-link block confirmation session can be added to the block confirmation function field of the ADDBA response frame, and the ADDBA response frame includes a block confirmation function field, and the block confirmation function field includes information for indicating the function type of the multi-link block confirmation session. The information in the ADDBA response frame indicates that the multi-link block confirmation session is a multi-link block confirmation response. Figure 8 As shown, the Block Ack Function field may include field values ​​0-255, for example, a field value 0 indicates an ADDBA request function, a field value 1 indicates an ADDBA response function, a field value 2 indicates a BA session deletion, etc. The Block Ack Function field also includes field values ​​3-127, 131, and 134-255, which are reserved field values ​​and may be used to indicate a function type of a multi-link block acknowledgment session, including a multi-link block acknowledgment request, a multi-link block acknowledgment response, a multi-link block acknowledgment session teardown, etc.

[0102] The ADDBA response frame may include a second block confirmation parameter set field, and the second block confirmation parameter set field includes the second buffer size field. Figure 9 As shown, Figure 9 This is a schematic diagram of a Block Acknowledgement Parameter Set field provided in an embodiment of the present application. The Block Acknowledgement Parameter Set field may include a 1-bit A-MSDU, a 2-bit Block Acknowledgement Policy, a 3-bit Service Type, and a 10-bit Buffer Size field. The 10-bit Buffer Size field may be used to indicate the size of the global buffer space. The sizes of the various fields are not limited.

[0103] Optionally, a multi-link element may be added to the ADDBA response frame, wherein the ADDBA response frame includes the multi-link element. Figure 10 As shown, Figure 10This is a schematic diagram of a multilink element provided by an embodiment of the present application. The multilink element includes an element number, a length field, and an indication field. The indication field may include a link bitmap field and at least one first buffer size field. The number of first buffer size fields is equal to the number of bits set to "1" in the link bitmap. The link bitmap may indicate which links participate in a multilink BA session. For example, if link 1 participates in establishing a multilink BA session, link 2 does not participate, link 3 does not participate, and link 4 participates, the bitmap may represent 1001. Secondly, the indication field may include a link number field, multiple link identity number fields, and at least one first buffer size field. The number of link identity number fields and the number of first buffer size fields are the same as the value of the link number field. The link identity number field is used to indicate which links participate in establishing a multilink BA session. Furthermore, the multilink element also includes multiple block acknowledgment start sequence control fields, with the number of block acknowledgment start sequence control fields equal to the number of links participating in the multilink BA session. Among them, the above-mentioned indication field is not limited to being carried in the multi-link element, and can also be carried in the existing fields or elements in the ADDBA request frame or response frame, such as the multi-band (Multi-Band) element or the ADDBA extension element.

[0104] It should be noted that one or more first buffer size fields and second buffer size fields can also be carried through other fields. For example, the first buffer size field can also be indicated by the block confirmation parameter set field, and the second buffer size field can also be indicated by the multi-link element. The two can also be indicated in other ways, which are not limited here.

[0105] Optionally, after the first device receives the ADDBA response frame sent by the second device, the first device may return an acknowledgment frame Ack for responding to the ADDBA response frame to the second device, and then the second device receives the acknowledgment frame Ack sent by the first device.

[0106] After steps S601 and S602, a multi-link block confirmation dialogue is established between the multiple links of the first device and the multiple links of the second device, and then the following operations are performed:

[0107] S603: The first device sends a data packet to the second device. The second device receives a data frame containing the data packet sent by the first device. The data packet may be a data packet MAC service data unit (MSDU) or an aggregated MAC service data unit (A-MSDU) formed by aggregating multiple data packet MSDUs. The second device may also send a management frame and a control frame containing a MAC management protocol data unit (MMPDU). The data packet may be a quality of service (QoS) data packet.

[0108] Another example Figure 11 As shown, the high MAC layer of the first device maintains a global buffer space, and the high MAC layer assigns a global sequence number to each of the data packets received and passed down from the upper layer. For multiple data packets with the same <receiving address, service type>, they can be divided into the same group of data packets, and the same group of data packets can share a 12-bit sequence number space ranging from 0 to 4095. Of course, there are other methods of assigning global sequence numbers, such as classifying data packets sent to the same address as the same group of data packets, and the same group of data packets share a sequence number space, which is not limited by the present invention. Each time the high MAC layer receives a data packet (belonging to the same group of data packets), the global sequence number increases by 1. For example, if there are 3 data packets in the global buffer space, and the 3 data packets are in the same group of data packets, the first data packet is assigned a global sequence number 1, the second data packet is assigned a global sequence number 2, and the third data packet is assigned a global sequence number 3. The global sequence number is an identifier assigned to the data packet by the multi-link entity.

[0109] The low MAC layer of the link of the first device can take out multiple data packets from the global buffer space of the high MAC layer and assign local sequence numbers. Similarly, for multiple data packets with the same <receiving address, service type> on the link, they can be divided into the same group of data packets, and the same group of data packets can share a 12-bit sequence number space ranging from 0 to 4095. Of course, there are other methods of assigning local sequence numbers, such as classifying data packets sent to the same address as the same group of data packets, and the same group of data packets share a sequence number space, which is not limited by the present invention. Each time the link receives a data packet (belonging to the same group of data packets), the local sequence number increases by 1. For example, if Figure 9As shown, there are 3 data packets on 2 links respectively, the 3 data packets are the same group of data packets, the numbers in the brackets are local sequence numbers, and the numbers outside the brackets are global sequence numbers, the low MAC layer of each link respectively assigns a local sequence number to the 3 data packets, and the local sequence numbers are sequentially increased. Among them, the local sequence number is the identifier assigned to the data packet by the link that transmits the data packet in the plurality of links.

[0110] As shown in Figure 14 Figure 14 A schematic diagram of a MAC header provided by an embodiment of the application. After the global sequence number and the local sequence number are assigned, the low MAC of each link respectively adds a MAC header, which can include one or more of the frame control field, the address 1 field (receiving address), the address 2 field (transmitting address), the address 3 field, the sequence control field, the address 4, the QoS control field, and the HT control field. Among them, the 2-byte sequence control field can include a 12-bit sequence number and a 4-bit fragment number. One of the local sequence number and the global sequence number can be carried through the sequence control field, and the other can be carried through other fields, for example, in the HT control field, or an additional sequence control field is added in the frame carrier. Finally, the data packet can be sent to the second device.

[0111] Among them, the first device can maintain a plurality of first sending windows and a second sending window according to the ADDBA request frame and the ADDBA response frame. The plurality of first sending windows correspond to the plurality of links of the first device, and the second sending window corresponds to the multi-link entity of the first device. Further, each link maintains a first sending window, and one of the first sending windows corresponds to one of the plurality of links, and the starting sequence number of one of the first sending windows is WinStartO1, the ending sequence number is WinEndO1, and the window size is WinSizeO1, wherein the WinSizeO1 is equal to the confirmation value of the first buffer size field corresponding to the link. And the high MAC layer also maintains a second sending window, the starting sequence number of the second sending window is WinStartO2, the ending sequence number is WinEndO2, and the window size is WinSizeO2, wherein the WinSizeO2 is equal to the confirmation value of the second buffer size field negotiated through the ADDBA request frame and the ADDBA response frame.

[0112] ​After the second device receives the data packet, the PHY layer of each link passes the data packet to the lower MAC layer of that link. The lower MAC layer of each link can obtain the local sequence number from the MAC header of each data packet and maintain a first scoreboard based on the local sequence number. This first scoreboard is used to respond to acknowledgments of data packets of the same type received on that link. The first scoreboard can be used to count whether each link has correctly received the data packet. If the data packet is correctly received, the data packet is counted as 1; if the data packet is not received, the data packet is counted as 0. In addition, the ADDBA request frame includes one or more first block acknowledgment start sequence number control fields. The first block acknowledgment start sequence number control field includes a first initial sequence number, which indicates the first receive window (optional) of the second device and the initial value of the start sequence number of the first scoreboard. The first initial sequence number type is a local sequence number. The link can sequentially acknowledge the data packets received on the link according to the first initial sequence number, ultimately forming a block acknowledgment bitmap of the data packets acknowledged by the second device. This bitmap is included in a partial block acknowledgment frame and returned to the first device. The Partial Block Acknowledgement frame is used to acknowledge multiple data packets received on this link. This Partial Block Acknowledgement frame is an immediate response to a data packet received on the link, or it can be a response to a BAR frame received on the link that indexes the local sequence number. The size of the Block Acknowledgement bitmap in the Partial Block Acknowledgement frame can be negotiated using the First Buffer Size field in the ADDBA Request and ADDBA Response frames. Block Acknowledgement bitmaps of different lengths may exist for the same First Buffer Size field. See the 802.11ax protocol for details.

[0113] Among them, the second device can maintain multiple first scoreboards, and the multiple first scoreboards correspond to multiple links. The starting sequence number of one of the first scoreboards is WinStartR1, and the ending sequence number is WinEndR1; the initial value of WinStartR1 is the first initial sequence number of the first block confirmation start sequence number control field in the ADDBA request frame, and the size of the first scoreboard WinSizeR1 is equal to the smaller value of the confirmation value of the first buffer size field corresponding to the corresponding link and the maximum length block confirmation bit map. The positions of WinStartR1 and WinEndR1 will move with the received data packets. For details, please refer to the 802.11-2016 protocol, which will not be repeated here. WinStartR1 determines the starting sequence number of the bit map of the local block confirmation frame (such as a compressed block confirmation frame or a multi-site block confirmation frame) returned by the second device.

[0114] Optionally, the second device may also maintain multiple first receiving windows based on the ADDBA request frame and the ADDBA response frame, and the first receiving window is used to sort the received data packets and then submit them to the high MAC layer in sequence. The multiple first receiving windows correspond to the multiple links of the second device. Furthermore, one first receiving window corresponds to one link among the multiple links. The starting sequence number of the first receiving window is WinStartB1, the ending sequence number is WinEndB1, and the window size is WinSizeB1. Among them, the initial value of WinStartB1 is the first initial sequence number of the first block confirmation start sequence number control field in the ADDBA request frame, and the WinSizeB1 is equal to the smaller value of the confirmation value of the first buffer size field corresponding to the link and the maximum length block confirmation bit map. The positions of WinStartB1 and WinEndB1 will move with the received data packets. For details, please refer to the 802.11-2016 protocol, which will not be repeated here. In one possible implementation, the second device does not need to maintain multiple first receiving windows based on the ADDBA request frame and the ADDBA response frame.

[0115] Optionally, the lower MAC layer of each link of the second device can pass multiple data packets to the high MAC layer in sequence according to the order of the local sequence numbers of the multiple data packets. In another embodiment, the lower MAC layer of each link directly passes the received multiple data packets to the high MAC layer.

[0116] Then, the high MAC layer obtains the global sequence number from each data packet, and maintains a second scoreboard based on the global sequence number. The second scoreboard is used to respond to the confirmation of the data packets of the same type received by the multi-link entity. The second scoreboard can be used to count whether the multi-link entity has correctly received the data packet. If the data packet is received correctly, the data packet can be counted as 1, and if the data packet is not received, the data packet can be counted as 0. The ADDBA request frame includes a second block confirmation start sequence number control field, and the second block confirmation start sequence number control field includes a second initial sequence number. The second initial sequence number is used to indicate the second receiving window of the second device and the initial value of the start sequence number of the second scoreboard. The type of the second initial sequence number is a global sequence number. The high MAC layer can confirm multiple data packets in sequence according to the second initial sequence number, and finally form a block confirmation bit map of the received data packets confirmed by the second device, and include it in the global block confirmation frame and return it to the first device. A global block acknowledgement frame is a response to a block acknowledgement request frame received by a multilink entity, which is used to index a global sequence number. The size of the block acknowledgement bitmap in the global block acknowledgement frame depends on the second buffer size field negotiated through the ADDBA request frame and the ADDBA response frame. Block acknowledgement bitmaps of different lengths may exist for the same second buffer size field. Optionally, the global block acknowledgement frame is an acknowledgment of multiple data packets received by the multilink entity.

[0117] Among them, the second device can maintain multiple second scoreboards, the second scoreboards correspond to the multi-link entities, the starting sequence number of the second scoreboard is WinStartR2, the ending sequence number is WinEndR2, and the window size is WinSizeR2, wherein the initial value of WinStartR2 is the second initial sequence number of the second block confirmation starting sequence number control field in the ADDBA request frame, and the WinSizeR2 is equal to the smaller value of the confirmation value of the second buffer size field and the maximum length block confirmation bit map. The positions of WinStartR2 and WinEndR2 will move with the received data packets. For details, please refer to the 802.11-2016 protocol, which will not be repeated here. WinStartR2 determines the starting sequence number of the bit map of the global block confirmation frame (such as a compressed block confirmation frame or a multi-site block confirmation frame) returned by the second device.

[0118] Among them, the second device can also maintain a second receiving window based on the ADDBA request frame and the ADDBA response frame. The second receiving window can be used to sort the data packets received by the multi-link entity in the global buffer space according to the global sequence number, and pass the data packets to the upper layer of the MAC layer of the second device in sequence according to the order of the global sequence number. The second receiving window corresponds to the link entity of the second device. Furthermore, the starting sequence number of the second receiving window is WinStartB2, the ending sequence number is WinEndB2, and the window size is WinSizeB2, wherein the initial value of WinStartB2 is the second initial sequence number of the second block confirmation starting sequence number control field in the ADDBA request frame, and the WinSizeB2 is equal to the smaller value of the confirmation value of the second buffer size field and the maximum length block confirmation bit map. The positions of WinStartB2 and WinEndB2 can move with the received data packets. For details, please refer to the 802.11-2016 protocol, which will not be repeated here.

[0119] S604: The first device sends a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame to the second device. The second device receives the block acknowledgment request frame or the multi-user block acknowledgment request trigger frame sent by the first device. This step is optional and depends on the acknowledgment policy of the transmitted data packet. If the policy is block acknowledgment, step S604 is required. If the policy is normal acknowledgment or implicit block acknowledgment, step S604 is not required, and the data packet index is immediately fed back.

[0120] like Figure 15 As shown, Figure 15This is a schematic diagram of a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame provided by an embodiment of the present application. The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame may include a starting sequence number control field, the starting sequence number control field includes a starting sequence number, the block acknowledgment request frame or the multi-user block acknowledgment request trigger frame also includes a BAR control field, the BAR control field includes first indication information, the first indication information is used for the type of the starting sequence number, the type of the starting sequence number includes a local sequence number or a global sequence number. The block acknowledgment request frame (for example, a variant of the block acknowledgment request frame, including a multi-service type BAR, an extended compression BAR, a compression BAR, a multicast BAR or a basic BAR, etc.) or the multi-user block acknowledgment request trigger frame includes a global block acknowledgment request frame and a local block acknowledgment request frame. The block acknowledgment request frame can be determined to be a global block acknowledgment request frame or a local block acknowledgment frame based on the BAR type indicated by the first indication information. The starting sequence number in the starting sequence number control field in a block acknowledgment request frame (for example, a variant of a block acknowledgment request frame, including a multi-service type BAR, an extended compression BAR, a compression BAR, a multicast BAR, or a basic BAR, etc.) or a multi-user block acknowledgment request trigger frame is the starting local sequence number or the starting global sequence number indicated by the first indication information.

[0121] S605. The second device sends a confirmation message in response to the data packet to the first device. The first device receives a confirmation message in response to the data packet replied by the second device. The confirmation message includes a block confirmation frame. The block confirmation frame includes a global block confirmation frame and a local block confirmation frame. The block confirmation frame can be a compressed block confirmation frame or a multi-site block confirmation frame, etc.

[0122] like Figure 16 As shown, Figure 16An embodiment of the present application provides a schematic diagram of a block acknowledgment frame, wherein the block acknowledgment frame may include a starting sequence number control field, the starting sequence number control field including a starting sequence number and a block acknowledgment bitmap; the block acknowledgment bitmap is used to indicate the reception status of the data packet received by the second device, and the block acknowledgment frame (including variants of the block acknowledgment frame, such as basic block acknowledgment, compressed block acknowledgment, multi-site block acknowledgment, and multi-service type block acknowledgment, etc.) may further include a BA control field, the BA control field including second indication information, the second indication information being used to indicate whether the starting sequence number in the starting sequence control field in the block acknowledgment frame is a local sequence number or a global sequence number, and the first bit in the block acknowledgment bitmap corresponds to the starting sequence number, and each bit in the bitmap corresponds to the same type of sequence number. The block acknowledgment frame (for example, variants of the block acknowledgment frame, including basic block acknowledgment, compressed block acknowledgment, multi-site block acknowledgment, and multi-service type block acknowledgment, etc.) includes a global block acknowledgment frame and a local block acknowledgment frame. The block acknowledgment frame can be determined to be a global block acknowledgment frame or a local block acknowledgment frame based on the BA type indicated by the second indication information.

[0123] In which, the block confirmation frame may include a block confirmation bit map. If the sequence corresponding to the block confirmation bit map is the local sequence number, the sequence number corresponding to the first bit in the block confirmation bit map is the local starting sequence number in the WinStartR1 or start sequence control field; if the sequence corresponding to the block confirmation bit map is the global sequence number, the sequence number corresponding to the first bit in the block confirmation bit map is the global starting sequence number in the WinStartR2 or start sequence control field.

[0124] In this embodiment of the present application, through negotiation using ADDBA request and ADDBA response frames, the first and second devices allocate a local buffer space for each of the multiple links, and a global buffer space for the higher MAC layer. This establishes a multi-link block acknowledgement dialogue. Furthermore, the MAC address of the data packet sent by the first device includes both the local sequence number and the global sequence number. This allows the first device to send the same type of data packet to the second device across multiple links, thereby improving data communication efficiency.

[0125] like Figure 17 As shown, Figure 17 : This is a flow chart of a data frame transmission method provided in an embodiment of the present application. The steps in the embodiment of the present application at least include:

[0126] S1701: A first device sends a message frame to a second device, and the second device receives the message frame sent by the first device. The message frame includes first indication information, and the first indication information is used to indicate a primary link among the multiple links. The following two optional methods are included:

[0127] In a first optional manner, the first indication information is a special element. The first device may send a message frame to the second device via a primary link. The message frame may carry a special element (e.g., an element related to multi-link information). The special element is only carried in the message frame sent via the primary link. The special element is used to indicate that the link transmitting the message frame is the primary link. The message frame may be a beacon frame in a management frame.

[0128] A second optional method is that the first indication information is a link sequence number, and the first device can send a message frame to the second device through a non-main link. The message frame can carry a reduced neighbor report element or a multi-band element. The reduced neighbor report element or the multi-band element includes a link sequence number, and the link sequence number is used to indicate the main link of multiple links.

[0129] S1702, the first device sends a second indication message to the second device through the main link, or negotiates a target wake up time (TWT) with the second device through the main link. The second indication message indicates the working state or sleep state of multiple links. TWT negotiation is used for the first device and the second device to negotiate one or more service windows, work within the service window, and sleep outside the service window, thereby saving power.

[0130] In a specific implementation, the second indication information may be carried in the operating mode indication field (OMI) of the high throughput (HT) control field in the MAC header or in an operating mode notification frame. The second indication information may be a bitmap. For example, if the nth bit is set to a value of 1, it indicates that the nth link is about to enter a dormant state or a closed state. If the nth bit is set to a value of 0, it indicates that the nth link is about to enter an active state. The second indication information may include multiple link numbers. If the second indication information includes link number 1, the link corresponding to link number 1 is in a dormant state or a closed state, and vice versa.

[0131] like Figure 18 As shown, Figure 18 This is a schematic diagram of a TWT element for TWT negotiation provided by an embodiment of the present application, wherein the TWT element includes element number, length, control and TWT parameter information fields. Among them, the control field includes NDP paging indication, responder power saving mode, negotiation type, TWT information frame disable and other fields. The negotiation type may include single-user TWT type and broadcast TWT type. Figure 19 As shown, Figure 19 This is a schematic diagram of a single-user TWT type provided by an embodiment of the present application. When the negotiation type indicates a single-user TWT type, the information field of the single-user TWT parameter includes the request type, target wake-up time, TWT group allocation, minimum TWT wake-up duration, TWT wake-up duration decimal, TWT channel, NDP (Null data packet) paging, etc. Figure 20 As shown, Figure 20 This is a schematic diagram of a broadcast TWT type provided by an embodiment of the present application. When the negotiation type indicates a broadcast TWT type, the information field of the broadcast TWT parameter includes the request type, target wake-up time, TWT group allocation, minimum TWT wake-up duration, TWT wake-up duration decimal, TWT channel, and NDP (Null data packet) paging. Among them, the request type field includes an indication field of the TWT wake-up interval, and the TWT wake-up interval = TWT wake-up duration decimal * 2 (TWT wake-up interval index).

[0132] Among them, a multi-link indication can be added to the control field of the TWT element. The multi-link indication is used to indicate that the broadcast TWT parameter information or the single-user TWT parameter information can be applied on another link different from the link that transmits the TWT element. Which link is specifically applied can be indicated in the following ways:

[0133] For single-user TWT:

[0134] The first optional method is to add an operating class field to the information field of the single-user TWT parameter, and combine the operating class field and the TWT channel field to indicate which link among multiple links the TWT element is applied to.

[0135] The second optional method is to add one or more link numbers in the information field of the single-user TWT parameter and the information field of the broadcast TWT parameter. The link number is used to indicate which link among the multiple links the TWT element is applied to.

[0136] Alternatively, the link sequence number bitmap is used to indicate on which link among the multiple links the TWT element is applied. For example, if the link sequence number bitmap is 0100, then setting the second bit to 1 can indicate that the TWT element can be applied on the second link.

[0137] For broadcast TWT:

[0138] The first optional mode is to add an operating class field and a TWT channel field in the information field of the broadcast TWT parameter, to indicate which link in the multiple links to which the TWT element is applied.

[0139] The second optional mode is to add one or more link serial numbers in the information field of the broadcast TWT parameter, to indicate which link in the multiple links to which the TWT element is applied. Alternatively, a link serial number bitmap is used to indicate which link in the multiple links to which the TWT element is applied. For example, if the link serial number bitmap is 0100, the second bit being 1 indicates that the TWT element can be applied to the second link.

[0140] In the embodiment of the present application, the first device indicates the main link in the multiple links to the second device, and indicates the working state or the sleep state of the multiple links through the main link, or performs TWT negotiation through the main link, thereby achieving the effect of saving power.

[0141] The above describes the method of the embodiment of the present application in detail, and the apparatus of the embodiment of the present application is provided below.

[0142] Please refer to Figure 21 , Figure 21 is a structural schematic diagram of a first communication apparatus provided by the embodiment of the present application, which comprises a sending module 2101, a receiving module 2102 and a processing module 2103, and the detailed description of each module is as follows.

[0143] The sending module 2101 is configured to send an ADDBA request frame to a second device, wherein the ADDBA request frame comprises a reference value of at least one first buffer size field and a reference value of a second buffer size field; the second device and the first device are a multi-link entity comprising one or more links.

[0144] The receiving module 2102 is configured to receive an ADDBA response frame sent by the second device, wherein the ADDBA response frame comprises an acknowledgement value of at least one first buffer size field and an acknowledgement value of the second buffer size field.

[0145] The processing module 2103 is configured to establish a multi-link block acknowledgement session between the multiple links of the first device and the multiple links of the second device according to the ADDBA request frame and the ADDBA response frame.

[0146] Among them, the first buffer size field is used to indicate the size of a local buffer space corresponding to one of the multiple links of the first device and the second device, and the second buffer size field is used to indicate the size of a global buffer space maintained by the first device and the second device.

[0147] Optionally, the processing module 2103 is used to maintain multiple first sending windows and one second sending window based on the ADDBA request frame and the ADDBA response frame, wherein the multiple first sending windows correspond to the multiple links of the first device, and the second sending window corresponds to the multi-link entity of the first device.

[0148] wherein, one of the first sending windows corresponds to one of the multiple links, a starting sequence number of the first sending window is WinStartO1, an ending sequence number is WinEndO1, and a window size is WinSizeO1, wherein WinSizeO1 is equal to a confirmed value of a first buffer size field corresponding to the link;

[0149] The starting sequence number of the second sending window is WinStartO2, the ending sequence number is WinEndO2, and the window size is WinSizeO2, wherein WinSizeO2 is equal to the confirmation value of the second buffer size field negotiated through the ADDBA request frame and the ADDBA response frame.

[0150] A processing module is used to maintain multiple first sending windows and one second sending window according to the ADDBA request frame and the ADDBA response frame, wherein the multiple first sending windows correspond to the multiple links of the first device, and the second sending window corresponds to the multi-link entity of the first device.

[0151] wherein, one of the first sending windows corresponds to one of the multiple links, a starting sequence number of the first sending window is WinStartO1, an ending sequence number is WinEndO1, and a window size is WinSizeO1, wherein WinSizeO1 is equal to a confirmed value of a first buffer size corresponding to the link;

[0152] The starting sequence number of the second sending window is WinStartO2, the ending sequence number is WinEndO2, and the window size is WinSizeO2, wherein WinSizeO2 is equal to the confirmation value of the second buffer size negotiated through the ADDBA request frame and the ADDBA response frame.

[0153] Wherein, the ADDBA request frame includes a first block confirmation starting sequence number control field and a second block confirmation starting sequence number control field;

[0154] The first block confirmation starting sequence number control field is used to indicate a first initial sequence number of a starting sequence number of a first scoreboard of a link of the second device, where the type of the first initial sequence number is a local sequence number;

[0155] The second block confirmation starting sequence number control field is used to indicate a second initial sequence number of a starting sequence number of a second scoreboard of a multi-link entity of the second device, and the type of the second initial sequence number is a global sequence number.

[0156] The ADDBA request frame includes at least one of a link bitmap field and a reference value of the at least one first buffer size field, or at least one of a link number field, a multiple link identification number field, and a reference value of the at least one first buffer size field; the ADDBA response frame includes at least one of a link bitmap field and a confirmation value of the at least one first buffer size field, or at least one of a link number field, a multiple link identification number field, and a confirmation value of the at least one first buffer size field;

[0157] The ADDBA request frame includes a first block confirmation parameter set field, wherein the first block confirmation parameter set field includes a reference value of the second buffer size field;

[0158] The ADDBA response frame includes a second block confirmation parameter set field, and the second block confirmation parameter set field includes a confirmation value of the second buffer size field.

[0159] Optionally, the sending module 2101 is configured to send a data packet to the second device; the receiving module 2102 is configured to receive a confirmation message in response to the data packet replied by the second device;

[0160] The data packet includes a local sequence number and a global sequence number. The local sequence number is an identifier assigned to the data packet by the link that sends the data packet among the multiple links, and the global sequence number is an identifier assigned to the data packet by the multi-link entity.

[0161] Optionally, the sending module 2101 is further configured to send a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame to the second device, where the block acknowledgment request frame or the multi-user block acknowledgment request trigger frame includes a starting sequence number control field, where the starting sequence number control field includes a starting sequence number;

[0162] The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame further includes first indication information, where the first indication information is used to indicate a type of the starting sequence number, where the type of the starting sequence number includes a local sequence number or a global sequence number.

[0163] The receiving module 2102 is further configured to receive a block confirmation frame sent by the second device, the block confirmation frame including a starting sequence number control field, the starting sequence number control field including a starting sequence number and a block confirmation bit map; the block confirmation bit map is used to indicate a reception status of the data packet received by the second device;

[0164] The block acknowledgment frame also includes a block acknowledgment BA control field, the BA control field includes the second indication information, the second indication information is used to indicate the type of the starting sequence number, the type of the starting sequence number is a local sequence number or a global sequence number, and the first bit in the block acknowledgment bit map corresponds to the starting sequence number.

[0165] In another embodiment:

[0166] The sending module 2101 is used to send a message frame to the second device, where the message frame includes first indication information, where the first indication information is used to indicate a main link among multiple links. The sending module 2101 is used to send second indication information to the second device via the main link, where the second indication information indicates the working status or sleep status of the multiple links, or to perform TWT negotiation with the second device via the main link.

[0167] The first indication information is a special element. The first device can send a message frame to the second device via the primary link. The message frame can carry a special element. This special element is only carried in message frames sent via the primary link. The special element is used to indicate that the link transmitting the message frame is the primary link. By indicating the primary link with the special element, other links are put into a dormant or closed state, thereby saving power.

[0168] Among them, the first indication information is the link sequence number. The first device can send a message frame to the second device through a non-main link. The message frame can carry a reduced version of the neighbor report element or a multi-band element. The reduced version of the neighbor report element or the multi-band element includes a link sequence number, which is used to indicate the main link of multiple links.

[0169] Among them, an operation type field is added to the information field of the single-user TWT parameter and the information field of the broadcast TWT parameter, and the operation type field and the TWT channel field are combined to indicate which link among multiple links the TWT element is applied to. An indication value can be added to the broadcast TWT parameter information field, and the indication value is used to indicate which link among multiple links the TWT element is applied to.

[0170] Among them, one or more link sequence numbers are added to the information field of the single-user TWT parameter and the information field of the broadcast TWT parameter, and the link sequence number is used to indicate which link among the multiple links the TWT element is applied to. Alternatively, a link sequence number bit map is used to indicate which link among the multiple links the TWT element is applied to.

[0171] It should be noted that the implementation of each module can also refer to Figure 6 and Figure 17 The corresponding description of the method embodiment shown executes the method and functions performed by the first device in the above embodiment.

[0172] See Figure 22 , Figure 22 22 is a structural diagram of a second communication device provided in an embodiment of the present application. The second communication device includes a receiving module 2201, a sending module 2202 and a processing module 2203, wherein each module is described in detail as follows.

[0173] A receiving module 2201 is configured to receive an ADDBA request frame sent by a first device, where the ADDBA request frame includes at least a reference value of a first buffer size field and a reference value of a second buffer size field; the first device and the second device are multi-link entities including one or more links;

[0174] a sending module 2202, configured to send an ADDBA response frame to the first device, the ADDBA response frame including a confirmation value of the at least one first buffer size field and a confirmation value of the second buffer size field;

[0175] The processing module 2203 is configured to establish a multi-link block confirmation dialogue between the multiple links of the first device and the multiple links of the second device according to the ADDBA request frame and the ADDBA response frame;

[0176] Among them, the first buffer size field is used to indicate the size of a local buffer space corresponding to one of the multiple links of the first device and the second device, and the second buffer size field is used to indicate the size of a global buffer space maintained by the first device and the second device.

[0177] a processing module 2203, configured to maintain a receiving window according to the ADDBA request frame and the ADDBA response frame, wherein the receiving window corresponds to the link entity of the second device;

[0178] The receiving window starting sequence number is WinStartB2, the ending sequence number is WinEndB2, and the window size is WinSizeB2, wherein WinSizeB2 is equal to the smaller value of the confirmation value of the second buffer size field and the maximum length block confirmation bitmap.

[0179] Wherein, the ADDBA request frame includes a first block confirmation starting sequence number control field and a second block confirmation starting sequence number control field;

[0180] The first block confirmation starting sequence number control field is used to indicate a first initial sequence number of a starting sequence number of a first scoreboard of a link of the second device, where the type of the first initial sequence number is a local sequence number;

[0181] The second block confirmation starting sequence number control field is used to indicate a second initial sequence number of a starting sequence number of a second scoreboard of a multi-link entity of the second device, and the type of the second initial sequence number is a global sequence number.

[0182] The ADDBA request frame includes at least one of a link bitmap field and a reference value of the at least one first buffer size field, or at least one of a link number field, a plurality of link identity number fields, and a reference value of the at least one first buffer size field;

[0183] The ADDBA response frame includes at least one of a link bitmap field and a confirmation value of the at least one first buffer size field, or at least one of a number of links field, a plurality of link identity number fields, and a confirmation value of the at least one first buffer size field;

[0184] The ADDBA request frame includes a first block confirmation parameter set field, wherein the first block confirmation parameter set field includes a reference value of the second buffer size field;

[0185] The ADDBA response frame includes a second block confirmation parameter set field, and the second block confirmation parameter set field includes a confirmation value of the second buffer size field.

[0186] Optionally, the receiving module 2201 is further configured to receive a data packet sent by the first device; the sending module 2202 is further configured to send a confirmation message in response to the data packet to the first device;

[0187] The data packet includes a local sequence number and a global sequence number. The local sequence number is an identifier assigned to the data packet by the link that sends the data packet among the multiple links, and the global sequence number is an identifier assigned to the data packet by the multi-link entity.

[0188] Optionally, the receiving module 2201 is further configured to receive a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame sent by the first device, where the block acknowledgment request frame or the multi-user block acknowledgment request trigger frame includes a starting sequence number control field, where the starting sequence number control field includes a starting sequence number;

[0189] The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame further includes first indication information, where the first indication information is used to indicate a type of the starting sequence number, and the type of the starting sequence number includes a local sequence number or a global sequence number.

[0190] The processing module 2203 is configured to maintain a plurality of first scoreboards and a second scoreboard; the plurality of first scoreboards correspond to the plurality of links, and the second scoreboard corresponds to the multi-link entity;

[0191] The starting sequence number of the first scoreboard is WinStartR1, and the ending sequence number is WinEndR1; the scoreboard size WinSizeR1 is equal to the smaller value of the confirmation value of the first buffer size field corresponding to the corresponding link and the maximum length block confirmation bitmap;

[0192] The starting sequence number of the second scoreboard is WinStartR2, the ending sequence number is WinEndR2, and the scoreboard size is WinSizeR2, wherein WinSizeR2 is equal to the smaller value of the confirmation value of the second buffer size field and the maximum length block confirmation bit map.

[0193] Wherein, the confirmation message is a block confirmation frame;

[0194] The block acknowledgment frame includes a starting sequence number control field, the starting sequence number control field includes a starting sequence number and a block acknowledgment bit map; the block acknowledgment bit map is used to indicate a reception status of the data packet received by the second device;

[0195] The block acknowledgment frame also includes a block acknowledgment BA control field, the BA control field includes the second indication information, the second indication information is used to indicate the type of the starting sequence number, the type of the starting sequence number is a local sequence number or a global sequence number, and the first bit in the block acknowledgment bit map corresponds to the starting sequence number.

[0196] If the sequence corresponding to the block confirmation bitmap is the local sequence number, the sequence number corresponding to the first bit in the block confirmation bitmap is WinStartR1;

[0197] If the sequence corresponding to the block confirmation bitmap is the global sequence number, the sequence number corresponding to the first bit in the block confirmation bitmap is WinStartR2.

[0198] In another embodiment:

[0199] The receiving module 2201 is used to receive a message frame sent by the first device, where the message frame includes first indication information, where the first indication information is used to indicate a main link among multiple links. The receiving module 2201 is used to receive second indication information sent by the first device through the main link, where the second indication information indicates the working status or sleep status of multiple links, or performs TWT negotiation with the first device through the main link.

[0200] Among them, the first indication information is a special element. The second device can receive a message frame sent by the first device through the main link. The message frame can carry a special element. The special element is only carried in the message frame sent by the main link. The special element is used to indicate that the link transmitting the message frame is the main link.

[0201] Among them, the first indication information is the link sequence number. The second device can receive a message frame sent by the first device through a non-main link. The message frame can carry a reduced version of the neighbor report element or a multi-band element. The reduced version of the neighbor report element or the multi-band element includes a link sequence number, which is used to indicate the main link of multiple links.

[0202] It should be noted that the implementation of each module can also refer to Figure 6 and Figure 17 The corresponding description of the method embodiment shown executes the method and functions performed by the second device in the above embodiment.

[0203] Please continue to refer to Figure 23 , Figure 23 This is a schematic diagram of the structure of a first device proposed in an embodiment of the present application. Figure 23 As shown, the first device may include: at least one processor 2301 , at least one communication interface 2302 , at least one memory 2303 and at least one communication bus 2304 .

[0204] Among them, the processor 2301 can be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a transistor logic device, a hardware component or any combination thereof. It can implement or execute the various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of this application. The processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processor and a microprocessor, and so on. The communication bus 2304 can be a peripheral component interconnect standard PCI bus or an extended industry standard architecture EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 23 It is represented by only one thick line, but it does not mean that there is only one bus or one type of bus. The communication bus 2304 is used to realize the connection and communication between these components. Among them, the communication interface 2302 of the device in the embodiment of the present application is used to communicate signaling or data with other node devices. The memory 2303 may include volatile memory, such as non-volatile dynamic random access memory (NVRAM), phase change random access memory (PRAM), magnetoresistive random access memory (MRAM), etc., and may also include non-volatile memory, such as at least one disk storage device, electrically erasable programmable read-only memory (EEPROM), flash memory devices, such as NOR flash memory or NAND flash memory, semiconductor devices, such as solid state disk (SSD), etc. The memory 2303 may optionally be at least one storage device located away from the aforementioned processor 2301. The memory 2303 may optionally store a set of program codes, and the processor 2301 may optionally execute the program executed in the memory 2303 .

[0205] The communication interface 2302 sends an ADDBA request frame to the second device, where the ADDBA request frame includes at least a reference value of a first buffer size field and a reference value of a second buffer size field; the first device and the second device are multi-link entities including one or more links;

[0206] The communication interface 2302 receives an ADDBA response frame sent by the second device, where the ADDBA response frame includes a confirmation value of the at least one first buffer size field and a confirmation value of the second buffer size field;

[0207] establishing, according to the ADDBA request frame and the ADDBA response frame, a multi-link block acknowledgement dialogue between the multiple links of the first device and the multiple links of the second device;

[0208] Among them, the first buffer size field is used to indicate the size of a local buffer space corresponding to one of the multiple links of the first device and the second device, and the second buffer size field is used to indicate the size of a global buffer space maintained by the first device and the second device.

[0209] Optionally, the processor 2301 is further configured to perform the following operations:

[0210] According to the ADDBA request frame and the ADDBA response frame, the first device maintains a plurality of first sending windows and a second sending window, wherein the plurality of first sending windows correspond to a plurality of links of the first device, and the second sending window corresponds to a multi-link entity of the first device;

[0211] wherein, one of the first sending windows corresponds to one of the multiple links, a starting sequence number of the first sending window is WinStartO1, an ending sequence number is WinEndO1, and a window size is WinSizeO1, wherein WinSizeO1 is equal to a confirmed value of a first buffer size corresponding to the link;

[0212] The starting sequence number of the second sending window is WinStartO2, the ending sequence number is WinEndO2, and the window size is WinSizeO2, wherein WinSizeO2 is equal to the confirmation value of the second buffer size negotiated through the ADDBA request frame and the ADDBA response frame.

[0213] Wherein, the ADDBA request frame includes at least one first block confirmation starting sequence number control field and a second block confirmation starting sequence number control field;

[0214] The first block confirmation starting sequence number control field is used to indicate a first initial sequence number of a starting sequence number of a first scoreboard of a link of the second device, where the type of the first initial sequence number is a local sequence number;

[0215] The second block confirmation starting sequence number control field is used to indicate a second initial sequence number of a starting sequence number of a second scoreboard of a multi-link entity of the second device, and the type of the second initial sequence number is a global sequence number.

[0216] The ADDBA request frame includes at least one of a link bitmap field and a reference value of the at least one first buffer size field, or at least one of a link number field, a plurality of link identity number fields, and a reference value of the at least one first buffer size field;

[0217] The ADDBA response frame includes at least one of a link bitmap field and a confirmation value of the at least one first buffer size field, or at least one of a number of links field, a plurality of link identity number fields, and a confirmation value of the at least one first buffer size field;

[0218] The ADDBA request frame includes a first block confirmation parameter set field, wherein the first block confirmation parameter set field includes a reference value of the second buffer size field;

[0219] The ADDBA response frame includes a second block confirmation parameter set field, and the second block confirmation parameter set field includes a confirmation value of the second buffer size field.

[0220] Optionally, the processor 2301 is further configured to perform the following operations:

[0221] The communication interface 2302 sends a data packet to the second device;

[0222] The communication interface 2302 receives a confirmation message in response to the data packet replied by the second device;

[0223] The data packet includes a local sequence number and a global sequence number. The local sequence number is an identifier assigned to the data packet by the link that sends the data packet among the multiple links, and the global sequence number is an identifier assigned to the data packet by the multi-link entity.

[0224] Optionally, the processor 2301 is further configured to perform the following operations:

[0225] The communication interface 2302 sends a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame to the second device, where the block acknowledgment request frame or the multi-user block acknowledgment request trigger frame includes a starting sequence number control field, where the starting sequence number control field includes a starting sequence number;

[0226] The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame further includes first indication information, where the first indication information is used to indicate a type of the starting sequence number, where the type of the starting sequence number includes a local sequence number or a global sequence number.

[0227] Optionally, the processor 2301 is further configured to perform the following operations:

[0228] receiving a block confirmation frame sent by the second device, the block confirmation frame including a starting sequence number control field, the starting sequence number control field including a starting sequence number and a block confirmation bit map; the block confirmation bit map is used to indicate a reception status of the data packet received by the second device;

[0229] The block acknowledgment frame also includes a block acknowledgment BA control field, the BA control field includes the second indication information, the second indication information is used to indicate the type of the starting sequence number, the type of the starting sequence number is a local sequence number or a global sequence number, and the first bit in the block acknowledgment bit map corresponds to the starting sequence number.

[0230] In another embodiment:

[0231] A message frame is sent to the second device through the communication interface 2302, where the message frame includes first indication information, where the first indication information is used to indicate a main link among multiple links. Second indication information is sent to the second device through the main link, where the second indication information indicates the working status or sleep status of the multiple links, or a TWT negotiation is performed with the second device through the main link.

[0232] The first indication information is a special element. The first device can send a message frame to the second device via the primary link. The message frame can carry a special element. This special element is only carried in message frames sent via the primary link. The special element is used to indicate that the link transmitting the message frame is the primary link. By indicating the primary link with the special element, other links are put into a dormant or closed state, thereby saving power.

[0233] Among them, the first indication information is the link sequence number. The first device can send a message frame to the second device through a non-main link. The message frame can carry a reduced version of the neighbor report element or a multi-band element. The reduced version of the neighbor report element or the multi-band element includes a link sequence number, which is used to indicate the main link of multiple links.

[0234] Among them, an operation type field is added to the information field of the single-user TWT parameter and the information field of the broadcast TWT parameter, and the operation type field and the TWT channel field are combined to indicate which link among multiple links the TWT element is applied to. An indication value can be added to the broadcast TWT parameter information field, and the indication value is used to indicate which link among multiple links the TWT element is applied to.

[0235] Among them, one or more link sequence numbers are added to the information field of the single-user TWT parameter and the information field of the broadcast TWT parameter, and the link sequence number is used to indicate which link among the multiple links the TWT element is applied to. Alternatively, a link sequence number bit map is used to indicate which link among the multiple links the TWT element is applied to.

[0236] Furthermore, the processor can also cooperate with the memory and the communication interface to perform the operations of the first device in the above-mentioned application embodiment.

[0237] Please continue to refer to Figure 24 , Figure 24 24 is a schematic diagram of a second device according to an embodiment of the present application. As shown in the figure, the second device may include: at least one processor 2401, at least one communication interface 2402, at least one memory 2403, and at least one communication bus 2404.

[0238] The processor 2401 may be any of the aforementioned processors. The communication bus 2404 may be a PCI bus or an EISA bus. The bus may be divided into an address bus, a data bus, a control bus, and the like. Figure 24 It is represented by only one thick line, but it does not mean that there is only one bus or one type of bus. The communication bus 2404 is used to realize the connection and communication between these components. Among them, the communication interface 2402 of the device in the embodiment of the present application is used to communicate signaling or data with other node devices. The memory 2403 can be the various types of memory mentioned above. The memory 2403 can also be at least one storage device located away from the aforementioned processor 2401. A set of program codes are stored in the memory 2403, and the processor 2401 executes the program executed by the above-mentioned OAM in the memory 2403.

[0239] Receiving, through the communication interface 2402, an ADDBA request frame sent by a first device, the ADDBA request frame including at least a reference value of a first buffer size field and a reference value of a second buffer size field; the first device and the second device are multi-link entities including one or more links;

[0240] an ADDBA response frame sent to the first device through the communication interface 2402, the ADDBA response frame including a plurality of confirmation values ​​of the first buffer size field and a confirmation value of the second buffer size field;

[0241] establishing, according to the ADDBA request frame and the ADDBA response frame, a multi-link block acknowledgement dialogue between the multiple links of the first device and the multiple links of the second device;

[0242] Among them, the first buffer size field is used to indicate the size of a local buffer space corresponding to one of the multiple links of the first device and the second device, and the second buffer size field is used to indicate the size of a global buffer space maintained by the first device and the second device.

[0243] Optionally, the processor 2401 is further configured to perform the following operations:

[0244] The second device maintains a receiving window according to the ADDBA request frame and the ADDBA response frame, wherein the receiving window corresponds to the link entity of the second device;

[0245] The receiving window starting sequence number is WinStartB2, the ending sequence number is WinEndB2, and the window size is WinSizeB2, wherein WinSizeB2 is equal to the smaller value of the confirmation value of the second buffer size field and the maximum length block confirmation bitmap.

[0246] Optionally, the processor 2401 is further configured to perform the following operations:

[0247] According to the ADDBA request frame and the ADDBA response frame, the second device maintains multiple first receiving windows and one second receiving window, wherein the multiple first receiving windows correspond to the multiple links of the second device, and the second receiving window corresponds to the link entity of the second device.

[0248] Wherein, the ADDBA request frame includes a first block confirmation starting sequence number control field and a second block confirmation starting sequence number control field;

[0249] The first block confirmation starting sequence number control field is used to indicate a first initial sequence number of a starting sequence number of a first scoreboard of a link of the second device, where the type of the first initial sequence number is a local sequence number;

[0250] The second block confirmation starting sequence number control field is used to indicate a second initial sequence number of a starting sequence number of a second scoreboard of a multi-link entity of the second device, and the type of the second initial sequence number is a global sequence number.

[0251] The ADDBA request frame includes at least one of a link bitmap field and a reference value of the at least one first buffer size field, or at least one of a link number field, a plurality of link identity number fields, and a reference value of the at least one first buffer size field;

[0252] The ADDBA response frame includes at least one of a link bitmap field and a confirmation value of the at least one first buffer size field, or at least one of a number of links field, a plurality of link identity number fields, and a confirmation value of the at least one first buffer size field;

[0253] The ADDBA request frame includes a first block confirmation parameter set field, wherein the first block confirmation parameter set field includes a reference value of the second buffer size field;

[0254] The ADDBA response frame includes a second block confirmation parameter set field, and the second block confirmation parameter set field includes a confirmation value of the second buffer size field.

[0255] Optionally, the processor 2401 is further configured to perform the following operations:

[0256] receiving a data packet sent by the first device through the communication interface 2402;

[0257] Sending a confirmation message in response to the data packet to the first device through the communication interface 2402;

[0258] The data packet includes a local sequence number and a global sequence number. The local sequence number is an identifier assigned to the data packet by the link that sends the data packet among the multiple links, and the global sequence number is an identifier assigned to the data packet by the multi-link entity.

[0259] Optionally, the processor 2401 is further configured to perform the following operations:

[0260] receiving, through the communication interface 2402, a block acknowledgment request frame or a multi-user block acknowledgment request trigger frame sent by the first device, the block acknowledgment request frame or the multi-user block acknowledgment request trigger frame including a starting sequence number control field, the starting sequence number control field including a starting sequence number;

[0261] The block acknowledgment request frame or the multi-user block acknowledgment request trigger frame further includes first indication information, where the first indication information is used to indicate a type of the starting sequence number, where the type of the starting sequence number includes a local sequence number or a global sequence number.

[0262] Optionally, the processor 2401 is further configured to perform the following operations:

[0263] Maintaining a plurality of first scoreboards and a second scoreboard; the plurality of first scoreboards correspond to the plurality of links, and the second scoreboard corresponds to the multi-link entity;

[0264] The starting sequence number of the first scoreboard is WinStartR1, and the ending sequence number is WinEndR1; the scoreboard size WinSizeR1 is equal to the smaller value of the confirmation value of the first buffer size corresponding to the corresponding link and the maximum length block confirmation bitmap;

[0265] The starting sequence number of the second scoreboard is WinStartR2, the ending sequence number is WinEndR2, and the scoreboard size is WinSizeR2, wherein WinSizeR2 is equal to the smaller value of the confirmation value of the second buffer size and the maximum length block confirmation bit map.

[0266] Wherein, the confirmation message is a block confirmation frame;

[0267] The block acknowledgment frame includes a starting sequence number control field, the starting sequence number control field includes a starting sequence number and a block acknowledgment bit map; the block acknowledgment bit map is used to indicate a reception status of the data packet received by the second device;

[0268] The block acknowledgment frame also includes a block acknowledgment BA control field, the BA control field includes the second indication information, the second indication information is used to indicate the type of the starting sequence number, the type of the starting sequence number is a local sequence number or a global sequence number, and the first bit in the block acknowledgment bit map corresponds to the starting sequence number.

[0269] If the sequence corresponding to the block confirmation bitmap is the local sequence number, the sequence number corresponding to the first bit in the block confirmation bitmap is WinStartR1;

[0270] If the sequence corresponding to the block confirmation bitmap is the global sequence number, the sequence number corresponding to the first bit in the block confirmation bitmap is WinStartR2.

[0271] In another embodiment:

[0272] A message frame sent by the first device is received through the communication interface 2402, the message frame including first indication information, the first indication information being used to indicate a main link among multiple links. Second indication information is received through the communication interface 2402 and sent by the first device through the main link, the second indication information indicating the working state or sleep state of the multiple links, or performing TWT negotiation with the first device through the main link.

[0273] Among them, the first indication information is a special element. The second device can receive a message frame sent by the first device through the main link. The message frame can carry a special element. The special element is only carried in the message frame sent by the main link. The special element is used to indicate that the link transmitting the message frame is the main link.

[0274] Among them, the first indication information is the link sequence number. The second device can receive a message frame sent by the first device through a non-main link. The message frame can carry a reduced version of the neighbor report element or a multi-band element. The reduced version of the neighbor report element or the multi-band element includes a link sequence number, which is used to indicate the main link of multiple links.

[0275] Furthermore, the processor can also cooperate with the memory and the communication interface to execute the operations of the second device in the above-mentioned application embodiment.

[0276] An embodiment of the present application further provides a chip system, which includes a processor for supporting a first device or a second device to implement the functions involved in any of the above embodiments, such as generating or processing the data and / or information involved in the above method. In one possible design, the chip system may also include a memory, which is used for the necessary program instructions and data for the first device or the second device. The chip system can be composed of a chip or can include a chip and other discrete devices.

[0277] An embodiment of the present application further provides a processor, which is coupled to a memory and is used to execute any method and function involving the first device or the second device in any of the above embodiments.

[0278] An embodiment of the present application also provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute any method and function involving the first device or the second device in any of the above embodiments.

[0279] An embodiment of the present application also provides a device for executing any method and function involving the first device or the second device in any of the above embodiments.

[0280] An embodiment of the present application also provides a wireless communication system, which includes at least one first device and at least one second device involved in any of the above embodiments.

[0281] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk (SSD)).

[0282] The specific implementation methods described above further explain the purpose, technical solutions and beneficial effects of this application in detail. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Claims

1. A communication method applicable to multiple links, characterized in that: The method comprises: A first multi-link device performs target wake-up time TWT negotiation with a second multi-link device, where the TWT is applied to one or more links, and a TWT element used for the TWT negotiation includes a control field, where the control field includes a negotiation type field, where the negotiation type field is a single-user TWT type or a broadcast TWT type; wherein, when the negotiation type field indicates a single-user TWT type, the single-user TWT parameter information field in the TWT element includes a link sequence number bit map, where the link sequence number bit map is used to indicate one or more links to which the TWT element is applied.

2. The method according to claim 1, wherein The TWT element used for the TWT negotiation includes an element number field and a length field.

3. The method according to claim 1, wherein The control field also includes a multi-link indication field, which is used to indicate that the TWT parameter information shown can be applied on another link of the link that transmits the TWT element.

4. The method according to claim 1, wherein If a bit in the link sequence number bitmap is 1, it indicates that the TWT element is applied to the link corresponding to the bit.

5. The method according to claim 1, wherein The single-user TWT parameter information field also includes a request type field, the request type field includes a TWT wake-up interval indication field, the TWT wake-up interval indication field is used to indicate the TWT wake-up interval, the TWT wake-up interval = TWT wake-up duration decimal * 2 m , m = TWT wake-up interval index.

6. The method according to any one of claims 1 to 5, wherein: The single-user TWT parameter information field also includes at least one of a target wake-up time field, a TWT group allocation field, a minimum TWT wake-up duration field, a TWT wake-up duration decimal field, and a TWT channel field.

7. A communication method applicable to multiple links, characterized in that: The method comprises: The second multi-link device performs target wake-up time TWT negotiation with the first multi-link device, and the TWT is applied to one or more links. The TWT element used for the TWT negotiation includes a control field, and the control field includes a negotiation type field, and the negotiation type field is a single-user TWT type or a broadcast TWT type; wherein, when the negotiation type field indicates a single-user TWT type, the single-user TWT parameter information field in the TWT element includes a link sequence number bit map, and the link sequence number bit map is used to indicate one or more links to which the TWT element is applied.

8. The method according to claim 7, wherein The TWT element used for the TWT negotiation includes an element number field and a length field.

9. The method according to claim 7, wherein The control field also includes a multi-link indication field, which is used to indicate that the TWT parameter information shown can be applied on another link of the link that transmits the TWT element.

10. The method according to claim 7, wherein: If a bit in the link sequence number bitmap is 1, it indicates that the TWT element is applied to the link corresponding to the bit.

11. The method according to claim 7, wherein The single-user TWT parameter information field also includes a request type field, the request type field includes a TWT wake-up interval indication field, the TWT wake-up interval indication field is used to indicate the TWT wake-up interval, the TWT wake-up interval = TWT wake-up duration decimal * 2 m , m = TWT wake-up interval index.

12. The method according to any one of claims 7 to 11, wherein: The single-user TWT parameter information field also includes at least one of a target wake-up time field, a TWT group allocation field, a minimum TWT wake-up duration field, a TWT wake-up duration decimal field, and a TWT channel field.

13. A communication device, characterized in that: The apparatus comprises a processor and a memory, wherein the memory is used to store instructions, and the processor executes the instructions to enable the apparatus to perform the method according to any one of claims 1 to 6.

14. A communication device, characterized in that: The apparatus comprises a processor and a memory, wherein the memory is used to store instructions, and the processor executes the instructions to enable the apparatus to perform the method according to any one of claims 7 to 12.

15. A chip, characterized in that: The chip includes a processor and a communication interface, where the communication interface is used to communicate with an external device or an internal device, and the processor is used to implement the method according to any one of claims 1 to 6 or any one of claims 7 to 12.

16. A computer-readable storage medium, characterized in that Used to store instructions, when the instructions are executed on a computer, the computer is caused to execute the method according to any one of claims 1 to 6 or any one of claims 7 to 12.

17. A communication system, characterized in that: The system includes at least one first device and at least one second device, the first device is used to execute the method according to any one of claims 1 to 6, and the second device is used to execute the method according to any one of claims 7 to 12.

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