CN116963289A

CN116963289A - Multilink communication method and device

Info

Publication number: CN116963289A
Application number: CN202210366277.0A
Authority: CN
Inventors: 李云波; 郭宇宸; 淦明; 李伊青
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-04-08
Filing date: 2022-04-08
Publication date: 2023-10-27
Also published as: WO2023193666A1

Abstract

A method and apparatus for multilink communication, the method comprising: the first communication device generates a beacon frame and transmits the beacon frame; correspondingly, the second communication device receives the beacon frame, and receives downlink data on the link with the buffer data according to the beacon frame. The beacon frame includes a plurality of multi-link traffic indication elements, each of the plurality of multi-link traffic indication elements for indicating whether a corresponding non-AP MLD has buffered data on one or more links. The method effectively saves signaling overhead.

Description

Multilink communication method and device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for multilink communication.

Background

In the 802.11 protocol, a station (station, STA) of a non-access point (non-AP) has 2 operation modes, and one is a non-energy-saving mode, and is in an active state regardless of whether there is data transmission or not; the other is a power saving mode, and when the station needs to transmit data with an AP station (hereinafter referred to as an access point AP), the station can be in an active state; when no data transmission with the AP is required, the station may be in a sleep state (doze state) for saving power consumption. The station may tell the AP whether it is in power save mode by sending a frame to it, in particular by informing the station that it is in power save mode through the power save bit 1 in the frame control field (frame control field) in the medium access control (medium access control, MAC) header in the frame, or else in non-power save mode. In order to save power consumption of the station as much as possible, the AP may buffer downlink data of the station, wait for the station to wake up, and then send the downlink data to the station. But because of the limited buffer space of the AP, the AP may periodically send beacon frames informing its associated stations whether there is downlink data to be received through the traffic indication map (traffic indication map, TIM) TIM element in the beacon frame. The station in energy saving will wake up periodically to receive the beacon frame sent by the AP, if not, the station can switch to sleep state; otherwise, the station may choose a point in time to wake up to send an energy saving probe (PS-Poll) frame to the AP informing it of its wake up, which point in time is after the beacon frame reception point in time.

In multilink communication, an Access Point (AP) multilink device (AP MLD) may assign a unique association identifier (association identifier, AID) to a non-access point multilink device (non-AP MLD) as an identifier, so That All Stations (STAs) to which the non-AP MLD is attached may use the same AID. In case the non-AP MLD indicates a mapping of traffic identities to links (TID-to-link mapping), traffic of different TIDs is transmitted through different link sets. Since only 1 bit in the traffic indication bitmap (traffic indication map, TIM) element indicates the non-AP MLD, it is not possible to distinguish which links in the non-AP MLD the buffered data needs to be transmitted over, and thus it is unclear on which links the non-AP MLD needs to wake up to be ready to receive data. To address this problem, it is possible to indicate over which links data and MAC management protocol data units (MAC management protocol data unit, MMPDU) are buffered by a multi-link traffic indication element (multi-link traffic indication element).

However, the cost of the multi-link service indication element is larger at present, and the signaling cost can be further reduced.

Disclosure of Invention

The application provides a multilink communication method and a device, which can save signaling overhead of multilink service indication elements, in particular signaling overhead of bit map subfields of per-link service indication.

In a first aspect, an embodiment of the present application provides a method for multi-link communication, where the method may be applied to an AP or an AP MLD or a chip, and the chip may be disposed in the AP or the AP MLD, and the method includes:

generating a beacon frame, wherein the beacon frame comprises a plurality of multilink service indication elements, and each multilink service indication element in the multilink service indication elements is used for indicating whether corresponding non-access point multilink equipment (non-AP) MLD) has cache data on one or more links; and transmitting the beacon frame.

In general, the beacon frame includes a multi-link traffic indication element by which it is indicated whether all non-AP MLDs have buffered data on one or more links, where all non-AP MLDs shown herein refer to non-AP MLDs that have downlink data to receive as indicated by the partial virtual bit map field in the TIM element. The multiple per-link traffic indication bit bitmap subfields included in the per-link traffic indication list field in one multi-link indication element respectively indicate whether different non-AP MLDs have buffered data on one or more links, which results in the same bit length of the per-link traffic indication bit bitmap subfields, for example, m+1, for example, m is equal to the identifier of the link with the largest link identifier in all the non-AP MLDs needing to indicate whether the buffered data exists, and m is an integer greater than or equal to 0.

However, by the scheme provided by the embodiment of the application, the beacon frame comprises a plurality of multi-link service indicating elements, so that whether all non-AP MLDs have cached data on one or more links is indicated by the plurality of multi-link service indicating elements, and each multi-link service indicating element can be used for indicating whether part of non-AP MLDs in all non-AP MLDs have cached data on one or more links. Therefore, the bit length of the bitmap subfield of the service indication bit per link corresponding to the non-AP MLD with less number of links can be smaller, and the signaling overhead is effectively saved.

In a second aspect, an embodiment of the present application provides a multi-link communication method, which may be applied to an STA or a non-AP MLD or a chip, etc., where the chip may be disposed in the STA or the non-AP MLD, and the method includes:

receiving a beacon frame, wherein the beacon frame comprises a plurality of multilink service indication elements, and each multilink service indication element in the multilink service indication elements is used for indicating whether corresponding non-access point multilink equipment (non-AP) MLD) has cache data on one or more links; and receiving downlink data on a link with the buffer data according to the beacon frame.

With reference to the second aspect, in one possible implementation manner, the receiving downlink data on a link with buffered data according to the beacon frame includes: determining a multi-link service indication element corresponding to a non-AP MLD for receiving the beacon frame and/or a bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame according to the AID offset included in the multi-link service indication control field in each multi-link service indication element, wherein the bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame is contained in the multi-link service indication element corresponding to the non-AP MLD for receiving the beacon frame; determining a link corresponding to each bit in each link traffic indication bit map subfield corresponding to the non-AP MLD receiving the beacon frame according to a bit map size subfield included in a multi-link traffic indication control field in a multi-link traffic indication element corresponding to the non-AP MLD receiving the beacon frame; and determining a link with buffer data according to the value of each bit in the bit map subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame, and receiving downlink data on the link with the buffer data.

With reference to the second aspect, in one possible implementation manner, the determining, according to an AID offset included in a multilink traffic indication control field in each multilink traffic indication element, a multilink traffic indication element corresponding to a non-AP MLD receiving the beacon frame and/or a per-link traffic indication bit bitmap subfield corresponding to the non-AP MLD receiving the beacon frame includes: determining a bit bitmap subfield of each link service indication bit corresponding to a non-AP MLD receiving the beacon frame according to the AID offset included in the control field of each link service indication element, the value of the filling subfield and the value of the bit bitmap subfield of each link service indication bit; or determining a bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame according to the AID offset included in the multilink service indication control field in each multilink service indication element and the AID indication subfield.

With reference to the first aspect or the second aspect, in a possible implementation manner, the multilink traffic indication element includes a per-link traffic indication list field, and the per-link traffic indication list field includes a padding subfield.

With reference to the first aspect or the second aspect, in one possible implementation manner, the per-link traffic indication list field further includes one or more per-link traffic indication bit map subfields, each bit in the per-link traffic indication bit map subfields is used for indicating whether there is cache data on a corresponding link, a value of at least one bit in the per-link traffic indication bit map subfields is 1, and a value of all bits in the padding subfields is 0; the padding subfield is located after the bitmap subfield of each link traffic indication bit, and the value of all bits of the padding subfield is 0 to distinguish the padding subfield from the bitmap subfield of each link traffic indication bit, or the value of all bits of the padding subfield is 0 to indicate that the non-AP MLD receiving the beacon frame finishes parsing the bitmap field of each link traffic indication list.

In the embodiment of the application, the non-AP MLD can determine each link service indication bit bitmap subfield in the corresponding multilink service indication elements in the multiple multilink service indication elements according to the value characteristics of the filling subfield and the value characteristics of each link service indication bit bitmap subfield, so as to acquire the link with the cache data.

With reference to the first aspect or the second aspect, in a possible implementation manner, the per-link traffic indication list field further includes one or more per-link traffic indication bit bitmap subfields, each bit in the per-link traffic indication bit bitmap subfields is used for indicating whether there is buffered data on a corresponding link, and a bit length of the per-link traffic indication bit bitmap subfields is greater than or equal to a sum of link numbers associated with the non-AP MLD corresponding to the per-link traffic indication bit bitmap subfields.

In the embodiment of the application, the non-AP MLD can determine each link service indication bit bitmap subfield in the corresponding multilink service indication elements in a plurality of multilink service indication elements according to the sum of the associated link numbers and the relation between the bit lengths of each link service indication bit bitmap subfield, so as to acquire the link with the cache data.

With reference to the first aspect or the second aspect, in a possible implementation manner, the beacon frame further includes a traffic indication map TIM element, where the TIM element includes a partial virtual bit map field, where the partial virtual bit map field is used to indicate AIDs corresponding to the multiple multilink traffic indication elements; the multi-link service indication element comprises a multi-link service indication control field and a per-link service indication list field, the multi-link service indication control field comprises an associated identification AID offset sub-field, the per-link service indication list field comprises one or more per-link service indication bit bitmap subfields, and the AID offset sub-field is used for indicating AIDs corresponding to a first one of the one or more per-link service indication bit bitmap subfields.

In the embodiment of the application, since the beacon frame comprises a plurality of multi-link service indication elements, the AID offset can be used for indicating the AID corresponding to the first bit map sub-field of the first bit map of the one or more bits of the bit map of each link service indication included in the multi-link service indication element corresponding to the AID offset. The non-AP MLD may approximately determine the location of the bit map subfield per link traffic indication bit corresponding thereto according to the AID offset.

With reference to the first aspect or the second aspect, in one possible implementation manner, the multilink traffic indication control field further includes an AID indication subfield, where the AID offset subfield and the AID indication subfield are used to indicate an AID corresponding to each of the one or more bitmap subfields.

In the embodiment of the application, the non-AP MLD can clearly know the corresponding bit map sub-field of each link service indication bit by the AID offset sub-field and the AID indication sub-field.

With reference to the first aspect or the second aspect, in a possible implementation manner, the AID indication subfield is used to indicate a length of the AID corresponding to the one or more per-link traffic indication bit map subfields; or the AID indication subfield is used for indicating the AID corresponding to the last one of the one or more bit map subfields for per-link service indication; or, the AID indication subfield is used for indicating the number of the bit map subfields of the per-link service indication bit.

With reference to the first aspect or the second aspect, in a possible implementation manner, each of the multiple multilink traffic indication elements corresponds to a part of the non-AP MLDs in the non-AP MLDs with cached data indicated by the partial virtual bit map field.

In a third aspect, embodiments of the present application provide a communication device for performing the method of the first aspect or any possible implementation manner. The communication device comprises a device with means for performing the method of the first aspect or any possible implementation.

In a fourth aspect, embodiments of the present application provide a communications apparatus for performing the method of the second aspect or any of the possible implementations. The communication device comprises a unit with means for performing the method of the second aspect or in any possible implementation manner.

In a fifth aspect, an embodiment of the present application provides a communications device, including a processor configured to perform the method shown in the first aspect or any possible implementation manner. Alternatively, the processor is configured to execute a program stored in the memory, which when executed, performs the method according to the first aspect or any possible implementation manner described above.

In one possible implementation, the memory is located outside the communication device.

In one possible implementation, the memory is located within the communication device.

In the embodiment of the application, the processor and the memory may also be integrated in one device, i.e. the processor and the memory may also be integrated together.

In one possible implementation, the communication device further comprises a transceiver for receiving signals or transmitting signals.

In a sixth aspect, an embodiment of the present application provides a communications device, including a processor configured to perform the method shown in the second aspect or any possible implementation manner. Alternatively, the processor may be configured to execute a program stored in the memory, which when executed, performs the method of the second aspect or any possible implementation.

In embodiments of the present application, the processor and the memory may also be integrated in one device, i.e. the processor and the memory may also be integrated together.

In a seventh aspect, embodiments of the present application provide a communication device comprising logic circuitry and an interface, the logic circuitry and the interface being coupled; logic circuitry to generate a beacon frame; and an interface for inputting the beacon frame.

It will be appreciated that the description of the beacon frame may refer to the method of the first aspect or any possible implementation and will not be described in detail here.

In an eighth aspect, embodiments of the present application provide a communication device comprising logic circuitry and an interface, the logic circuitry and the interface being coupled; an interface for inputting a beacon frame; logic circuitry to input downstream data on the link with the buffered data based on the beacon frame.

It will be appreciated that the description of the beacon frame may refer to the method of the second aspect or any possible implementation and will not be described in detail here.

In a ninth aspect, embodiments of the present application provide a computer readable storage medium for storing a computer program which, when run on a computer, causes the method of the first aspect or any of the possible implementations of the first aspect to be performed.

In a tenth aspect, embodiments of the present application provide a computer readable storage medium for storing a computer program which, when run on a computer, causes the method of the second aspect or any of the possible implementations of the second aspect described above to be performed.

In an eleventh aspect, embodiments of the present application provide a computer program product comprising a computer program or computer code which, when run on a computer, causes the method shown in the first aspect or any of the possible implementations of the first aspect to be performed.

In a twelfth aspect, embodiments of the present application provide a computer program product comprising a computer program or computer code which, when run on a computer, causes the method shown in the second aspect or any possible implementation of the second aspect described above to be performed.

In a thirteenth aspect, embodiments of the present application provide a computer program which, when run on a computer, performs the method of the first aspect or any possible implementation of the first aspect.

In a fourteenth aspect, embodiments of the present application provide a computer program which, when run on a computer, performs the method of the second aspect or any of the possible implementations of the second aspect.

In a fifteenth aspect, an embodiment of the present application provides a wireless communication system, including a first communication device configured to perform a method as described in the first aspect or any possible implementation manner of the first aspect, and a second communication device configured to perform a method as described in the second aspect or any possible implementation manner of the second aspect.

Drawings

Fig. 1a is a schematic diagram of a communication system according to an embodiment of the present application;

fig. 1b is a schematic diagram of a communication system according to an embodiment of the present application;

fig. 1c is a schematic diagram of a communication system according to an embodiment of the present application;

fig. 2a is a schematic structural diagram of a multi-link service indication element according to an embodiment of the present application;

fig. 2b is a schematic structural diagram of a TIM element according to an embodiment of the present application;

fig. 2c is a schematic diagram of a relationship between a multi-link traffic indication element and a TIM element according to an embodiment of the present application;

fig. 3 is a schematic flow chart of a multi-link communication method according to an embodiment of the present application;

fig. 4a is a schematic structural diagram of a beacon frame according to an embodiment of the present application;

Fig. 4b is a schematic structural diagram of a beacon frame according to an embodiment of the present application;

fig. 4c is a schematic structural diagram of a beacon frame according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a sequence for assigning AIDs according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described with reference to the accompanying drawings.

The terms first and second and the like in the description, the claims and the drawings of the present application are used for distinguishing between different objects and not for describing a particular sequential order. Furthermore, the terms "comprising," "including," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion. Such as a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to the list of steps or elements but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

In the present application, "at least one (item)" means one or more, "a plurality" means two or more, "at least two (items)" means two or three and more, "and/or" for describing an association relationship of an association object, and three kinds of relationships may exist, for example, "a and/or B" may represent: only a, only B and both a and B are present, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of (a) or a similar expression thereof means any combination of these items. For example, at least one (one) of a, b or c may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c".

The method provided by the application can be applied to wireless local area network (wireless local area network, WLAN) systems, such as Wi-Fi and the like. The method provided by the application can be applied to the 802.11 series of protocols of the institute of electrical and electronics engineers (institute of electrical and electronics engineers, IEEE), such as 802.11a/b/g protocol, 802.11n protocol, 802.11ac protocol, 802.11ax protocol, 802.11be protocol or next generation protocol, etc., which are not listed here. The method provided by the application can be applied to various communication systems, such as an internet of things (internet of things, ioT) system, a vehicle to X (V2X), a narrowband internet of things (narrow band internet of things, NB-IoT) system, devices in the internet of vehicles, internet of things nodes, sensors and the like in the internet of things (IoT, internet of things), intelligent cameras in smart homes, intelligent remote controllers, intelligent water meter meters, sensors and the like in smart cities. It is also applicable to long term evolution (long term evolution, LTE) systems, fifth generation (5G) communication systems, and new communication systems (e.g., 6G) that are developed in future communication developments.

Although the embodiments of the present application will be described mainly by taking WLAN as an example, especially a network applied to IEEE 802.11 series standards. Those skilled in the art will readily appreciate that the various aspects of the present application are amenable to extension to other networks employing a variety of standards or protocols. Such as bluetooth (blue), high performance wireless LANs (high performance radio LAN, HIPERLAN), a wireless standard similar to the IEEE 802.11 standard and used principally in europe, and Wide Area Networks (WANs) or other now known or later developed networks. Accordingly, the various aspects provided by the present application may be applicable to any suitable wireless network, regardless of the coverage area and wireless access protocol used.

The following describes in detail the communication system and apparatus according to the present application.

The communication system provided by the application can be a WLAN or a cellular network, and the method provided by the application can be implemented by a communication device in a wireless communication system or a chip or a processor in the communication device, wherein the communication device can be a wireless communication device supporting parallel transmission of one or more links, for example, a multi-link device (MLD). A multi-link device has higher transmission efficiency and higher throughput than a device that supports only a single link transmission.

The multilink device comprises one or more affiliated stations, which are logical stations and can work on one link or one frequency band or one channel, etc. The affiliated station may be an Access Point (AP) or a non-AP station (non-access point station, non-AP STA). For convenience of description, the present application may refer to a multi-link device affiliated with a site as an AP as a multi-link AP or a multi-link AP device or an AP multi-link device (AP MLD). The multi-link device whose affiliated station is a non-AP STA is called a multi-link STA or multi-link STA device or STA multi-link device (STA multi-link device), or the multi-link device whose affiliated station is a non-AP STA is called a multi-link non-AP or multi-link non-AP device or non-AP multi-link device (non-AP MLD), or the like. The multi-link device with the affiliated station being an AP will hereinafter be referred to as an AP MLD, and the multi-link device with the affiliated station being a non-AP STA will hereinafter be referred to as a non-AP MLD. One or more APs belonging to the AP MLD are provided; the STA affiliated to the STA MLD is one or more.

A multi-link device (here, either a non-AP MLD or an AP MLD) is a communication apparatus having a wireless communication function. The communication device can be the equipment of a whole machine, a chip or a processing system arranged in the equipment of the whole machine, and the equipment provided with the chip or the processing system can realize the method and the function of the embodiment of the application under the control of the chip or the processing system. For example, the non-APMLD in the embodiment of the present application has a wireless transceiver function, can support an 802.11 series protocol, and can communicate with APMLD or other non-APMLD. For example, non-APMLD is any user communication device that allows a user to communicate with an AP and thus with a WLAN. For example, the non-APMLD may be a tablet computer, a desktop, a laptop, a notebook, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a handheld computer, a netbook, a personal digital assistant (personal digital assistant, PDA), a mobile phone, or other user equipment that can be networked, or an internet of things node in the internet of things, or an in-vehicle communication device in the internet of vehicles, or the like. The non-AP multilink device may also be a chip and processing system in these terminals. The APMLD may be a device that provides services for non-APMLD and may support the 802.11 family of protocols. For example, the APMLD may be a communication entity such as a communication server, a router, a switch, a bridge, or the like, or the APMLD may include various forms of macro base stations, micro base stations, relay stations, and the like, and of course, the APMLD may also be chips and processing systems in these various forms of devices. The 802.11 protocol may include a protocol supporting 802.11be or compatible with 802.11be, and so on, and is not listed here.

It can be appreciated that the multi-link device can support high-rate low-delay transmission, and as the wireless lan application scenario continuously evolves, the multi-link device can also be applied to more scenarios, such as sensor nodes (e.g., smart water meters, smart electric meters, smart air detection nodes) in smart cities, smart devices (e.g., smart cameras, projectors, display screens, televisions, speakers, refrigerators, washing machines, etc.) in smart homes, nodes in the internet of things, entertainment terminals (e.g., wearable devices such as AR, VR, etc.), smart devices (e.g., printers, projectors, etc.), internet of vehicles in the internet of vehicles, some infrastructures (e.g., vending machines, super self-service navigation stations, self-service cashing devices, self-service ordering machines, etc.) in daily life scenarios. The embodiments of the present application are not limited to the specific form of the multi-link device, but are merely illustrative.

In connection with the multi-link device shown above, fig. 1a is a schematic architecture diagram of a communication system according to an embodiment of the present application. As shown in fig. 1a, the AP MLD includes AP1, AP2, …, APn, and the non-AP MLD includes STA1, STA2, …, STAn. N is shown here as a positive integer. The AP MLD and non-AP MLD may communicate in parallel using link 1, link 2, …, link n. STA1 in the non-AP MLD establishes an association with AP1 in the AP MLD, STA2 in the non-AP MLD establishes an association with AP2 in the AP MLD, STA n in the non-AP MLD establishes an association with APn in the AP MLD, and so on. Thus, communication may be performed after an association is established between one or more STAs in the non-AP MLD and one or more APs in the AP MLD.

The frequency bands in which the multi-link device (including the AP MLD and the non-AP MLD) operates may include, but are not limited to: sub 1GHz,2.4GHz,5GHz,6GHz and high frequency 60GHz.

By way of example, FIG. 1b shows a scenario where an AP MLD101 communicates with Non-AP MLD102, non-AP MLD103 and STA104, the AP MLD101 comprising affiliated APs 101-1 through 101-3; the Non-AP MLD102 includes three STAs 102-1, 102-2 and 102-3 affiliated to each other; the Non-AP MLD103 includes 2 subordinate STAs 103-1, STAs 103-2; STA104-1, STA104 is a single link device. The AP MLD101 may communicate with the Non-AP MLD102 using link 1, link 2, and link 3, respectively; using link 2 and link 3 to communicate with Non-AP MLD 103; link 1 is employed to communicate with STA 104. In one example, STA104 operates in the 2.4GHz band; in the Non-AP MLD103, the STA103-1 works in the 5GHz band, and the STA103-2 works in the 6GHz band; in Non-AP MLD102, STA102-1 operates in the 2.4GHz band, STA102-2 operates in the 5GHz band, and STA102-3 operates in the 6GHz band. An AP101-1 operating in the 2.4GHz band in the AP MLD101 may transmit uplink or downlink data between the STA104 and the STA102-1 in the Non-AP MLD102 over link 1. The AP101-2 in the AP MLD101 operating in the 5GHz band can transmit uplink or downlink data between the link 2 and the STA103-1 in the Non-AP MLD103 operating in the 5GHz band, and can also transmit uplink or downlink data between the link 2 and the STA102-2 in the Non-AP MLD102 operating in the 5GHz band. The AP101-3 of the AP MLD101 operating in the 6GHz band can transmit uplink or downlink data between the STA102-3 of the Non-AP MLD102 operating in the 6GHz band through the link 3, and can also transmit uplink or downlink data between the STA103-2 of the Non-AP MLD through the link 3.

Fig. 1b only illustrates an example in which the AP MLD101 supports three frequency bands (2.4 ghz,5ghz,6 ghz), each corresponding to one link, and the AP MLD101 may operate in one or more of the links 1, 2, or 3. In practical applications, the AP MLD and the Non-AP MLD may also support more or fewer frequency bands, i.e., the AP MLD and the Non-AP MLD may operate on more links or fewer links, which is not limited in this embodiment of the present application. That is, the method provided by the embodiment of the application can be applied to not only multi-link communication but also single-link communication.

Fig. 1c is a schematic diagram of a communication system according to an embodiment of the present application. Reference may be made to fig. 1b in respect of the communication system shown in fig. 1c, i.e. fig. 1c and fig. 1b are only of different form. Based on the communication systems shown in fig. 1b and 1c, the AP MLD shown in the embodiments of the present application may be associated with one or more non-AP MLDs, and may also be associated with one or more legacy STA (legacy STA). In connection with the methods shown below, each bitmap subfield of each traffic per link, as seen from the AP side, corresponds to an AID, which may correspond to any of the conventional STA, single link MLD (e.g., STA), or multi-link MLD (e.g., non-AP MLD). However, from the STA side, the legacy STA may not read the corresponding bitmap subfield of the traffic indication bit per link, and the single link MLD may or may not read the corresponding bitmap subfield of the traffic indication bit per link, but the multi-link MLD (e.g., non-AP MLD) may necessarily read the corresponding bitmap subfield of the traffic indication bit per link.

The method provided by the application can be applied to but is not limited to: single user up/down transmission, multi-user up/down transmission, vehicle-to-anything (V2X, X may represent anything), device-to-device (D2D). For example, the V2X may include: vehicle-to-vehicle (vehicle to vehicle, V2V), vehicle-to-infrastructure (vehicle to infrastructure, V2I), vehicle-to-pedestrian communication (vehicle to pedestrian, V2P), or vehicle-to-network (vehicle to network, V2N), etc.

In a method of multilink communication, a beacon frame includes a multilink traffic indication element (multi-link traffic indication element) and a TIM element, the structure of which may be as shown in fig. 2a, and the structure of which may be as shown in fig. 2 b.

As shown in fig. 2a, the multilink traffic indication element includes at least one of: an element identifier (element ID) field, a length field, an element ID extension (element ID extension) field, a multi-link traffic indication control (multi-link traffic indication control) field, and a per-link traffic indication list (per-link traffic indication list) field. The multi-link traffic indication control field includes a bit bitmap size (bitmap size) subfield, an AID offset (AID offset) subfield, and a reserved subfield. The per-link traffic indication list field includes l per-link traffic indication bit bitmap (per-link traffic indication bitmap) subfields and possibly padding (padding) subfields. It will be appreciated that the byte (octets) length occupied by each field and the bit (bits) length occupied by each subfield as described above may be as shown in fig. 2a and will not be described in detail here.

In general, both the traffic indication bitmap (traffic indication map, TIM) beacon frame and the transmit traffic indication bitmap (delivery traffic indication map, DTIM) beacon frame carry traffic indication bitmap (traffic indication map, TIM) elements. As shown in fig. 2c, the TIM element includes at least one of: an element identifier (element ID) field, a length field, a DTIM count (DTIM count) field, a DTIM period (DTIM period) field, a bitmap control (bitmap control) field, and a partial virtual bitmap (partial virtual bitmap) field. Illustratively, the element ID field is used to identify the element as a TIM element; a length field for indicating a length of the TIM element; the DTIM count field is used for indicating how many TIM beacon frames appear before the arrival of the next DTIM beacon frame; the DTIM period field is used to indicate the period duration, i.e., inter-arrival, of the DTIM beacon frame. Bit bitmap control field bit 0 indicates whether there is downstream multicast data traffic when the AP transmits the DTIM beacon frame, and bits 1 to 7 indicate the offset of the partial virtual bit bitmap in bytes, i.e., 8 bits. For example, if the offset is 0, the partial virtual bit map starts with AID 1. If the offset is 1, the partial virtual bit map starts from AID 9. The partial virtual bitmap end bits are determined by the length field. The partial virtual bit map may be 251 bytes, i.e. 2008 bits, at maximum. Each bit in the partial virtual bit map field corresponds to an AID, and is used for indicating whether a station corresponding to the AID has unicast service. Or each bit in the partial virtual bit map field corresponds to a multicast AID, and is used for indicating whether a group of stations corresponding to the multicast AID have downlink traffic. Wherein the element ID field, the length field, the DTIM count field, the DTIM period field, and the bit map control field occupy 1 byte, respectively.

Fig. 2c is a schematic diagram of a relationship between a multi-link traffic indication element and a TIM element according to an embodiment of the present application. In the multi-link traffic indication element, each non-AP MLD with downlink buffered data corresponds to a bit map subfield per link traffic indication bit. And the size of all the bitmap subfields of the traffic indication bit per link is the same, for example, m+1, and the bits in the bitmap subfields of the traffic indication bit per link sequentially correspond to m+1 links from link identification (link ID) =0 to link id=m. Wherein m is the identification of the link with the largest link identification in all the links which need to be indicated in the non-AP MLD with the cache data, and m is an integer which is more than or equal to 0. The maximum link identification in the link corresponding to the bit with the value of 1 in the bit map sub-field of the per-link service indication bit included in the per-link service indication list field is the value of the bit map size sub-field. The bit length of the per-link traffic indication bit map subfield may be indicated by a bit map size subfield. For example, if the value of the bitmap size subfield is m, the length of the bitmap size subfield is m+1. It can be understood that the value carried in the bitmap size subfield in fig. 2c may be 0010, that is, the bit length of the bitmap size subfield indicating the bitmap size per link is 3 bits, and the value of each bit indicates whether there is cache data on the corresponding link, for example, whether there is cache data on link ID0 to link ID 2. For example, for the non-AP MLD with aid=k, the first bitmap sub-field per link traffic indication bit (i.e. bitmap 1 per link traffic indication bit) shown in fig. 2c carries a value of 010, which indicates that there is no cache data on link ID0 and link ID2 in the non-AP MLD with aid=k, and there is cache data on link ID 1. For the non-AP MLD with aid=k+1, there is no cache data on link ID0 and link ID2, and there is cache data on link ID 1. For the non-AP MLD with aid=k+3, there is cache data on link ID0 and link ID1, and cache data on link ID 2.

The value of l is equal to the sum of the numbers of bits of which the values of all subsequent bits are 1 from the bit corresponding to AID > =k in the partial virtual bit map field, and the value of the AID offset quantum field is equal to k. Thus, the aid=k corresponding to the first bit map subfield of each link traffic indication bit map in the traffic indication list field of each link, the AID corresponding to the bit map subfield of each link starts from aid=k, and sequentially corresponds to the AID with the value of 1 for all subsequent bits starting from the bit corresponding to aid=k in the virtual bit map field. That is, the non-AP MLD may determine the bitmap subfield of the traffic indication bit per link corresponding to the AID offset subfield according to the value of the AID offset subfield and the partial virtual bitmap field. In fig. 2c, since the bits corresponding to aid=k in the partial virtual bitmap field start, the total of three bits has a value of 1, and therefore, the number of bitmap subfields per link traffic indication bit is 3, such as bitmap subfield 1 per link traffic indication bit, bitmap subfield 2 per link traffic indication bit (not shown in fig. 2 c), and bitmap subfield 3 per link traffic indication bit.

As can be seen based on the multi-link communication method shown in fig. 2a to 2c, the signaling overhead of the above method is large when the number of non-AP MLDs is large or the number of links associated with different non-AP MLDs is different. For example, only one link (or a small number of links such as two links) of a link associated with a certain non-AP MLD buffers downlink data, where the bitmap subfield of each link traffic indication bit corresponding to the non-AP MLD still needs to indicate whether downlink data is buffered on each link of m+1 links.

Therefore, how to reduce the signaling overhead is urgently needed on the basis of accurately indicating to the non-AP MLD the links on which it has buffered data (i.e., accurately indicating on which links the non-AP MLD wakes up).

In view of this, the embodiments of the present application provide a method and apparatus for multilink communication, which can further reduce signaling overhead. The method provided by the embodiment of the application can be applied to the communication systems shown in fig. 1a to 1 c. Alternatively, the method may be applied to a first communication apparatus and a second communication apparatus, which may be the multilink device described above, for example, the first communication apparatus may include an AP or an AP MLD or a chip or the like, the chip may be provided to the AP or the AP MLD, the second communication apparatus may include a non-AP MLD, an STA or a chip or the like, and the chip may be provided to the non-AP MLD. The description of the first communication device and the second communication device may be referred to above, and will not be described in detail here.

Fig. 3 is a flow chart of a method for multi-link communication according to an embodiment of the present application. As shown in fig. 3, the method includes:

301. the first communication device generates a beacon frame including a plurality of multilink traffic indication elements, each of the plurality of multilink traffic indication elements for indicating whether a corresponding non-AP MLD has buffered data on one or more links.

Each of the plurality of multilink traffic indication elements comprises a multilink traffic indication control field and a per-link traffic indication list field, the multilink traffic indication control field comprising an AID offset subfield, the per-link traffic indication list field comprising one or more per-link traffic indication bit map subfields, the AID offset subfield being for indicating an AID corresponding to a first one of the one or more per-link traffic indication bit map subfields.

The beacon frame also includes a TIM element including a partial virtual bit map field for indicating AIDs corresponding to the plurality of multi-link traffic indication elements.

In the multi-link communication method shown in fig. 2a to 2c, the beacon frame includes a multi-link traffic indication element, through which the first communication device may indicate whether all non-AP MLDs have buffered data on one or more links, where all non-AP MLDs are indicated by a partial virtual bit map field in the TIM element as non-AP MLDs that have downlink data to be received.

However, in the embodiment of the present application, the beacon frame includes a plurality of multilink traffic indication elements, and the first communication device may indicate whether all non-AP MLDs have buffered data on one or more links through the plurality of multilink traffic indication elements, so that each multilink traffic indication element indicates whether some non-AP MLDs in the above all non-AP MLDs have buffered data on one or more links. That is, each of the plurality of multilink traffic indication elements included in the beacon frame corresponds to only a part of non-AP MLDs among the non-AP MLDs having the buffered data indicated by the partial virtual bit map field. Alternatively, it can be understood that: the non-AP MLD corresponding to each of the plurality of multilink traffic indication elements may be different or not exactly the same; or, the links corresponding to each of the multiple multilink service indication elements are different or not identical. For example, the plurality of multilink traffic indication elements includes a first multilink traffic indication element including a first multilink traffic indication control field and a first per-link traffic indication list field and a second multilink traffic indication element including a second multilink traffic indication control field and a second per-link traffic indication list field, the first per-link traffic indication list field and the second per-link traffic indication list field may be different (note that the following is not necessarily the case): the links corresponding to the first and the first per-link service indication list fields are different from the links corresponding to the second per-link service indication list fields; the maximum value of the link identifier in the link corresponding to the second and second per-link service indication list fields is larger than the maximum value of the link identifier in the link corresponding to the first per-link service indication list field; thirdly, the number of the bit map subfields of the service indication bit per link included in the first service indication list field per link is different from the number of the bit map subfields of the service indication bit per link included in the second service indication list field per link; fourth, the AID offset in the first multilink traffic indication control field is different from the AID offset in the second multilink traffic indication control field.

Fig. 4a is a schematic structural diagram of a beacon frame according to an embodiment of the present application. Fig. 4a shows only two multilink traffic indication elements by way of example, but should not be construed as limiting embodiments of the present application. As shown in fig. 4a, the AP MLD may determine the TIM element and the multi-link traffic indication element based on the AID of the non-AP MLD with buffered data when generating the plurality of multi-link traffic indication elements. For example, the value of the AID offset subfield in the first multi-link traffic indication element may be k, the number of corresponding bitmap subfields per link may be l1, l1 is an integer greater than or equal to 1, and the bitmap size subfield is determined based on the maximum identifier of the link with buffered data in the non-AP MLD corresponding to the l1 bitmap subfields per link respectively. The value of the AID offset quantum field in the second multi-link traffic indication element may be k+x, where x is determined based on the maximum value of AID corresponding to the l1 bit map sub-fields per link traffic indication bit in the first multi-link traffic indication element, and the non-AP MLD with buffered data after l1 non-AP MLD with buffered data from aid=k in the partial virtual bit map in the TIM element. And the number of the bitmap subfields of the per-link traffic indication bit can be l2, l2 is an integer greater than or equal to 1, and the bitmap size subfields are determined based on the maximum identifications of the links with cached data in the non-AP MLD respectively corresponding to the l2 bitmap subfields of the per-link traffic indication bit.

Illustratively, the first multi-link traffic indication element may correspond to a non-AP MLD of a link with a smaller link ID. For example, a first multi-link traffic indication element of the plurality of multi-link traffic indication elements may correspond to a non-AP MLD associated with only a link with link id=0, where the bitmap size has a value of 0000 as shown in table 1, and the bit length of the bitmap is 1 bit (x represents one bit in table 1); the second multi-link service indication element may correspond to a non-AP MLD with a link ID maximum value of 1 in the associated link, where the bit length of the bitmap is 2 bits per link service indication, as shown in table 1, where the value of the bitmap size is 0001; the third multi-link service indication element may correspond to a non-AP MLD with a link ID maximum value of 2 in the associated link, where the bit length of the bitmap is 3 bits per link service indication, as shown in table 1, where the value of the bitmap size is 0010; and so on, are not listed here. Of course, the first multi-link traffic indication element of the multiple multi-link traffic indication elements may correspond to a non-AP MLD with a link ID maximum value of 0 or 1 in the associated link, where the bit map size has a value of 0001, and the bit length of the bit map is 2 bits (x represents one bit in table 2) per link traffic indication; the second multi-link traffic indication element may correspond to a non-AP MLD with a link ID maximum of 2 or 3 in the associated link, where the bitmap size shown in table 2 has a value of 0010, and the bit length of the bitmap is 3 bits (x represents one bit in table 2) for each link traffic indication, and so on. The link corresponding to each of the multiple multilink traffic indication elements may depend on the implementation policy, which is not limited in the embodiment of the present application.

TABLE 1

TABLE 2

It will be appreciated that the examples shown in tables 1 and 2 are merely examples and should not be construed as limiting the embodiments of the present application. It should be noted that, when the value of the bitmap size subfield is 0000, there may be two methods for indicating the bitmap size subfield per link: in the first method, the bit length of the bit map subfield of each link service indication bit is 1 bit, and the value of the 1 bit is 1. In the second method, the per-link service indication list does not include the per-link service indication bit bitmap subfield, i.e., the per-link service indication bit bitmap subfield may not appear. For the second method, since only one bit in the link bit bitmap subfield has a value of 1, the non-AP MLD may consider that there is buffered data on the link corresponding to the bit having the value of 1 in the link bit bitmap. By the method II, the signaling overhead of the per-link service indication list field can be further reduced by optimizing the multi-link service indication element. It is understood that the second method may also be applied to the multilink traffic indication element shown in fig. 2 a. For example, when the value of the bit map size subfield is 0, the signaling overhead can be saved by the optimization method provided by the second method.

The method of the embodiment of the application can disperse all the non-AP MLDs needing to be indicated in a plurality of multi-link service indication elements, and the bit length of each link service indication bit bitmap subfield in each multi-link service indication element can be different, thereby saving signaling overhead. Further, to avoid the unordered mixing of non-AP MLDs of different link numbers, the AP MLDs may assign AIDs to the non-AP MLDs in a certain order.

Fig. 5 is an example of an order of assigning AIDs, where the segments are performed from small to large, the smallest AID is assigned to legacy stations (legacy STAs) (e.g., STAs that do not support EHT), then larger AIDs are assigned to non-AP MLDs associated only with links having link id=0, then larger AIDs are assigned to non-AP MLDs having link ID maximum of 1 in the associated links, …, and the largest part of AIDs is assigned to non-AP MLDs having link ID maximum of 14 (if any) in the associated links. Thus, according to the multiple multi-link traffic indication elements shown in the embodiment of the present application, taking fig. 5 as an example, for example, the bit bitmap size subfield in the first multi-link traffic indication element may have a value of 0 (i.e. the number of corresponding links is 1), so that the bit length of the bit bitmap subfield per link traffic indication is 1. The bit bitmap size subfield in the second multi-link traffic indication element may have a value of 1 (i.e. the number of corresponding links is 2), so that the bit length of the bit bitmap subfield per link traffic indication is 2, which is sequentially used to indicate whether there is cache data on the link with link id=0 and whether there is cache data on the link with link id=1.

It is understood that the beacon frame shown in the embodiment of the present application is only an example, and if other similar frames also have the functions of the related elements (such as the multi-link traffic indication element and the TIM element) carried in the beacon frame shown in the present application (or the functions of the related fields (such as the multi-link traffic indication control field and the per-link traffic indication list field) carried in the other similar frames), it is also within the scope of the present application.

302. The first communication device transmits a beacon frame, and the second communication device receives the beacon frame.

303. The second communication device receives downlink data on the link with the buffered data based on the beacon frame.

When the beacon frame includes a multi-link traffic indication element, the non-AP MLD corresponding to the bit map subfield of each link traffic indication bit may be determined according to the AID offset subfield and the partial virtual bit map field. However, when the beacon frame includes a plurality of multi-link traffic indication elements, since each multi-link traffic indication element corresponds to only a partial non-AP MLD (i.e., a partial non-AP MLD among the non-AP MLDs having buffered data) and the AID offset indicates only the AID corresponding to the first bit-per-link traffic indication bit map subfield of the multi-link traffic indication elements corresponding to the AID offset, the non-AP MLD cannot simply determine the bit-per-link traffic indication bit map subfield corresponding thereto from the AID offset subfield and the partial virtual bit map field when the multi-link traffic indication element includes a plurality of bit-per-link bit map subfields. Meanwhile, the non-AP MLD may misread the padding subfield included in the per-link traffic indication list field when parsing the per-link traffic indication bit bitmap subfield. Illustratively, there may be 0-7 bits Padding in the end portion of the per-link traffic indication list field such that the bit length of the entire per-link traffic indication list field is an integer multiple of 8 bits. When multiple multi-link traffic indication elements are used, since only a portion of the non-AP MLDs may be indicated in one multi-link traffic indication element, some of the non-AP MLDs may misinterpret the padding subfield as a bitmap subfield of each link traffic indication bit allocated to itself, thereby generating misreading.

Meanwhile, for the first communication device, in the process of generating multiple multilink service indication elements, it is assumed that, if one of the multiple multilink service indication elements shown in the embodiment of the present application includes l multiple multilink service indication bit bitmap subfields, l may satisfy the following conditions:

wherein Length is the value of the Length field in the certain multilink service indication element, L _indication The Bitmap Size is the value of the bit Bitmap Size subfield in the certain multilink service indication element. It will be appreciated that the conditions shown above apply to each of the multilink traffic indication elements.

That is, the first communication device may know the number of the multi-link traffic indication bit bitmap subfields in each multi-link traffic indication element, but if the second communication device is not explicitly informed of the multi-link traffic indication elements, the second communication device cannot explicitly know the number of the multi-link traffic indication bit bitmap subfields in each multi-link traffic indication element. Therefore, the embodiment of the present application provides the first implementation manner and the second implementation manner, and in the first implementation manner and the second implementation manner shown below, although the number of the bitmap subfields of the per-link traffic indication bit is not explicitly indicated in the multi-link traffic indication element, the second communication device may still obtain the bitmap subfields of the per-link traffic indication bit corresponding to the bitmap subfields of the per-link traffic indication bit through analysis. Meanwhile, the embodiment of the application also provides a third implementation mode, and in the third implementation mode shown below, the AID indication subfield is added in the multilink service indication element, so that the second communication device can clearly know the bit map subfield of each link service indication corresponding to the second communication device.

One implementation way,

The value of at least one bit in each link service indication bit map subfield is 1, and the value of all bits of the filling subfield is 0; the padding subfield is located after the bitmap subfield of each link traffic indication bit, and the value of all bits of the padding subfield is 0 to distinguish the padding subfield from the bitmap subfield of each link traffic indication bit, or the value of all bits of the padding subfield is 0 to indicate that the non-AP MLD receiving the beacon frame finishes analyzing the bitmap field of each link traffic indication list.

The AP MLD can distinguish the padding subfield from the per-link traffic indication bit bitmap subfield by setting all bits of the padding subfield to 0 when generating the beacon frame, or to instruct the non-AP MLD to end parsing the per-link traffic indication list field. That is, the padding subfield may be used to indicate that the padding subfield is not a bit map per link traffic subfield. Thus, when the AID indicated by the AID offset quantum field in the multi-link traffic indication element is not the AID of the non-AP MLD, the non-AP MLD may determine the bitmap subfield of each link traffic indication bit corresponding thereto according to the above principle. When the AID of the non-AP MLD is the AID indicated by the AID offset quantum field, the non-AP MLD may determine that the first per-link traffic indication bit bitmap subfield of the multi-link traffic indication element corresponding to the AID offset quantum field is the per-link traffic indication bit bitmap subfield to which the AP MLD transmits. Thus, a link with its own buffered data is determined based on the first per-link traffic indication bit map subfield. However, when the AID of the non-AP MLD is not the AID indicated by the AID offset subfield, since the length of the AID or the number of bitmap subfields per link traffic indication bit may not be included in the multi-link traffic indication element corresponding to the AID offset subfield, the non-AP MLD may determine the bitmap subfields per link traffic indication bit corresponding thereto according to the value of the bit in the bitmap subfields per link traffic indication bit and the value of the bit in the padding subfield.

For example, when a non-AP MLD discovers that there may be its own corresponding bitmap subfield of traffic indication bits per link in a certain multi-link traffic indication element, but all its bits are set to 0, the bitmap subfield of traffic indication bits per link is not interpreted, but is treated as a padding subfield. For example, the AID indicated by the AID offset subfield in a certain multi-link traffic indication element is k, that is, the multi-link traffic indication element must include a bit bitmap subfield per link traffic indication corresponding to the non-AP MLD with the AID k. However, if the AID of a certain non-a MLD is k+1, when the certain non-AP MLD acquires the multi-link traffic indication element, the bit following the bitmap subfield of the traffic indication bit per link corresponding to the AID of k in the multi-link traffic indication element may be mistaken for the bitmap subfield of the traffic indication bit per link corresponding to the certain non-AP MLD (the values are all 0). In one implementation manner, since the bit value after the bitmap subfield of each link traffic indication bit corresponding to the AID of k in the multi-link traffic indication element is 0, the certain non-AP MLD may not process it, but may be used as a padding subfield.

The second implementation mode,

The bit length of the per-link traffic indication bit map subfield is greater than or equal to the sum of the number of links associated with the non-AP MLD corresponding to the per-link traffic indication bit map subfield.

Because the bit length of each link traffic indication bit map subfield is determined based on the bit map size subfield, the value of the bit map size subfield is determined based on the identification of the link with the largest link identification in the links to be indicated in one or more non-AP MLDs (i.e., part of non-AP MLDs in all the non-AP MLDs shown in the embodiment of the present application) corresponding to the multi-link indication element, and therefore, the bit length of each link traffic indication bit map subfield is greater than or equal to the number of links associated with the non-AP MLD itself. When a non-AP MLD finds that the bit length of the per-link traffic indication bit map subfield in the multi-link traffic element is insufficient to indicate its own associated link (or enabled link), then it is determined that there is no per-link traffic indication bit map subfield associated with itself in the multi-link traffic indication element. In other words, when one non-AP MLD finds that the bit length of all the per-link traffic indication bit map subfields in the multi-link traffic element is less than the maximum link id+1 of its associated link, it is determined that there is no per-link traffic indication bit map subfield associated with itself in the multi-link traffic indication element.

For the first and second implementation, by adding multiple multilink traffic indication elements in the beacon frame, not only is signaling overhead effectively saved, but the structure of each multilink traffic indication element is minimally modified with respect to the multilink communication method shown in fig. 2a to 2 c.

The first and second implementations can be further understood as: the per-link traffic indication list field includes per-link traffic indication bit map subfields corresponding to non-AP MLDs and STAs in the partial virtual bit map field starting from aid=k. The per-link traffic indication list field includes l per-link traffic indication bit bitmap subfields, the number of l being the sum of the number of non-AP MLDs and STAs that take a value of 1 from aid=k to aid=p in a partial virtual bit bitmap field contained in a TIM element contained in a beacon frame carrying a multi-link traffic indication element. The AP MLD selects p according to the association/enabled link of the non-AP MLD and STA, how to select p out of the standard range. p is greater than or equal to k (The Per-Link Traffic Indication List field contains Per-Link Traffic Indication Bitmap subfields that correspond to The AIDs of The non-AP MLDs and STAs starting from The bit numbered k of The traffic indication virtual bitmap. The Per-Link Traffic Indication List field contains l Per-Link Traffic Indication Bitmap subfields, where l is The number of The bits that correspond to The AIDs of The non-AP MLDs and STAs and set to 1,counting from The bit numbered k to The bit numbered p of The traffic indication virtual bitmap,in The Partial Virtual Bitmap subfield of The TIM element that is included in a Beacon frame with The Multi-Link Traffic Indication element. The number p selected by AP MLD based on The associated/enabled links of associated STA and non-AP MLD, how to select p is out of scope of standard. The value of p is larger than or equal tok.). It can be understood that, k and p are extended to multiple multilink traffic indication elements with respect to one multilink traffic indication element, for example, the AID corresponding to each multilink traffic indication element in the multiple multilink traffic indication elements may be in turn: aid=k1 to aid=p1, aid=k2 to aid=p2, … … aid=kn to aid=pn, n representing the number of multilink traffic indication elements. Wherein k1 to kn may be carried in an AID offset quantum field included in each multilink traffic indication element, and p1 to pn may be autonomously determined by the AP MLD. When the number of bitmap subfields per link traffic indication bit included in the multi-link traffic indication element is 1, k=p.

The third implementation mode,

The multi-link service indication control field comprises an AID indication subfield, and the AID offset subfield and the AID indication subfield are used for indicating the AID corresponding to each of the one or more bit map sub-fields.

As one example, the AID indication subfield may include an AID length subfield that may be used to indicate a length of an AID corresponding to a multi-link traffic indication element corresponding to the AID length subfield; or, the AID length subfield is used to indicate the length of the AID corresponding to one or more bitmap subfields for per-link traffic indication bits included in the multi-link traffic indication element corresponding to the AID length subfield. It is understood that the length of the AID shown above may also be understood as the number of AIDs, or the like.

For example, table 3 is a multilink traffic indication control field shown in an embodiment of the present application. As shown in table 3, the multi-link traffic indication control field may include a bit map size subfield, an AID offset subfield, and an AID length subfield. For a description of the bitmap size subfield and the AID offset subfield, reference is made to the above, and details are not given here. For example, if the value indicated by the AID offset quantum field is k and the value indicated by the AID length subfield is q, the AID corresponding to the bitmap subfield of each link traffic indication bit included in the multi-link traffic indication element corresponding to the AID length subfield is non-AP MLD or STA with the corresponding bit value of 1 in the partial virtual bitmap in the TIM element from aid=k to aid=k+q in order, and q is an integer greater than or equal to 0. When q=0, it indicates that the number of bitmap subfields per link traffic indication bit included in the multi-link traffic indication element is 1.

TABLE 3 Table 3

Meaning (means)	Bit map size	AID offset	AID length	Reservation
					Bitmap size	AID offset	AID length	Reserved
Bits (bits)	4	11	11	6

It is understood that the respective bit lengths shown in table 3 are only examples and should not be construed as limiting the embodiments of the present application. According to the method, an AID Length subfield is introduced into a multi-link service indication element, and can be used for indicating that each link service indication bit bitmap subfield carried by the multi-link service indication element corresponds to a non-AP MLD or STA with the AID k+q indicated as 1 in a partial virtual bit bitmap field in a TIM element from AID k, k is carried in an AID offset quantum field, and q is the value of the AID Length field.

The example shown in table 3 can also be understood as: the per-link traffic indication list field includes per-link traffic indication bit map subfields corresponding to non-AP MLDs and STAs in the partial virtual bit map field starting from aid=k. The per-link traffic indication list field includes l per-link traffic indication bit bitmap subfields, the number of l being the sum of the number of non-AP MLDs and STAs that take a value of 1 from aid=k to aid=k+q in a partial virtual bit bitmap field contained in a TIM element contained in a beacon frame carrying a multi-link traffic indication element. q is indicated by AID length subfield, q is an integer greater than or equal to 0 (The Per-Link Traffic Indication List field contains Per-Link Traffic Indication Bitmap subfields that correspond to The AIDs of The non-AP MLDs and STAs starting from The bit numbered k of The traffic indication virtual bitmap. The Per-Link Traffic Indication List field contains l Per-Link Traffic Indication Bitmap subfields, where l is The number of The bits that correspond to The AIDs of The non-AP MLDs and STAs and set to 1,counting from The bit numbered k to The bit numbered k+q of The traffic indication virtual bitmap,in The Partial Virtual Bitmap subfield of The TIM element that is included in a Beacon frame with The Multi-Link Traffic Indication element. The number q is indicated in AID Length subfield. Q is an integer larger or equal to 0.). It is to be appreciated that the per-link traffic indication list field illustrated herein applies to each per-link traffic indication list field of the plurality of multilink traffic indication elements. The k and k+q are extended to a plurality of multilink traffic indication elements with respect to one multilink traffic indication element, for example, the AID corresponding to each multilink traffic indication element in the multilink traffic indication elements may be in turn: aid=k1 to aid=k1+q1, aid=k2 to aid=k2+q2, … … aid=kn to aid=kn+qn, n representing the number of multilink traffic indication elements. Wherein k1 to kn may be carried in an AID offset subfield included in each of the multi-link traffic indication elements, and q1 to qn may be carried in an AID length subfield included in each of the multi-link traffic indication elements.

As another example, the AID indication subfield may include an AID end subfield for indicating an AID corresponding to a last one of one or more per-link traffic indication bit bitmap subfields included in the multi-link traffic indication element corresponding to the AID end subfield.

For example, table 4 is a multilink traffic indication control field shown in an embodiment of the present application. As shown in table 4, the multi-link traffic indication control field may include a bit map size subfield, an AID offset subfield, and an end AID subfield. For a description of the bitmap size subfield and the AID offset subfield, reference is made to the above, and details are not given here. The end AID subfield may be used to indicate the AID to which the last per-link traffic indication bit map subfield in the multi-link traffic indication element corresponds.

TABLE 4 Table 4

It is understood that the respective bit lengths shown in table 4 are only examples and should not be construed as limiting the embodiments of the present application.

The example shown in table 3 can also be understood as: the per-link traffic indication list field includes per-link traffic indication bit map subfields corresponding to non-AP MLDs and STAs in the partial virtual bit map field starting from aid=k. The per-link traffic indication list field includes l per-link traffic indication bit bitmap subfields, the number of l being the sum of the number of non-AP MLDs and STAs that take a value of 1 from aid=k to aid=p in a partial virtual bit bitmap field contained in a TIM element contained in a beacon frame carrying a multi-link traffic indication element. p is indicated by The end AID subfield, p being greater than or equal to k (The Per-Link Traffic Indication List field contains Per-Link Traffic Indication Bitmap subfields that correspond to The AIDs of The non-AP MLDs and STAs starting from The bit numbered k of The traffic indication virtual bitmap. The Per-Link Traffic Indication List field contains l Per-Link Traffic Indication Bitmap subfields, where l is The number of The bits that correspond to The AIDs of The non-AP MLDs and STAs and set to 1,counting from The bit numbered k to The bit numbered p of The traffic indication virtual bitmap,in The Partial Virtual Bitmap subfield of The TIM element that is included in a Beacon frame with The Multi-Link Traffic Indication element. The number p is indicated in Ending AID subfield. The value of p is larger than or equal to k.). It is to be appreciated that the per-link traffic indication list field illustrated herein applies to each per-link traffic indication list field of the plurality of multilink traffic indication elements. The k and p are extended to a plurality of multilink traffic indication elements with respect to one multilink traffic indication element, for example, the AID corresponding to each multilink traffic indication element in the multilink traffic indication elements may be in turn: aid=k1 to aid=p1, aid=k2 to aid=p2, … … aid=kn to aid=pn, n representing the number of multilink traffic indication elements. Wherein k1 to kn may be carried in an AID offset subfield included in each of the multiple link traffic indication elements, and p1 to pn may be carried in an end AID subfield included in each of the multiple link traffic indication elements.

As yet another example, the AID indication subfield may include an AID number subfield that may be used to indicate the number of bit-map-per-link sub-fields included in the multi-link traffic indication element corresponding to the AID number field, or may be used to indicate the number of AIDs included in the multi-link traffic indication element corresponding to the AID number field, or may be used to indicate the number of non-AP MLDs indicated in the multi-link traffic indication element corresponding to the AID number field. In other words, the non-AP MLD may explicitly learn the number of bitmap subfields per link traffic indication included in the corresponding multi-link traffic indication element according to the AID digital field, and explicitly learn the bitmap subfields per link traffic indication corresponding to the AID with cached data indicated in the partial virtual bitmap field.

For example, table 5 is a multilink traffic indication control field shown in an embodiment of the present application. As shown in table 5, the multi-link traffic indication control field may include a bit map size subfield, an AID offset subfield, and an AID number (may also be referred to as an AID number) subfield. For a description of the bitmap size subfield and the AID offset subfield, reference is made to the above, and details are not given here. The AID number subfield may be used to indicate the number of bitmap subfields per link traffic indication bit in the multi-link traffic indication element, and the number of bitmap subfields per link traffic indication bit indicated by the AID number subfield may be a positive integer.

TABLE 5

Meaning (means)	Bit map size	AID offset	AID number	Reservation
					Bitmap size	AID offset	AID number	Reserved
Bits (bits)	4	11	11	6

It is understood that the respective bit lengths shown in table 5 are only examples and should not be construed as limiting the embodiments of the present application.

According to the method, the end corresponding to the last bit map sub-field of each link service indication bit carried by the multi-link service indication element is explicitly indicated by introducing the indication AID sub-field into the multi-link service indication element.

For the third implementation manner, by adding the AID indication subfield in the multi-link traffic indication element, the AID corresponding to each bit map subfield of per-link traffic indication bit can be explicitly indicated to the non-AP MLD, and the method is simple and direct.

According to the above three implementations, the method for determining, by the second communication device, a link with buffered data may include: determining a multi-link traffic indication element corresponding to the non-AP MLD of the received beacon frame and/or a bit map subfield of each link traffic indication bit corresponding to the non-AP MLD of the received beacon frame according to the AID offset included in the multi-link traffic indication control field in each multi-link traffic indication element (three implementations are described above); determining a link corresponding to each bit in each link traffic indication bit map subfield corresponding to the non-AP MLD of the received beacon frame according to the bit map size subfield included in the multi-link traffic indication control field in the multi-link traffic indication element corresponding to the non-AP MLD of the received beacon frame; and determining a link with buffer data according to the value of each bit in the bit map subfield of each link traffic indication bit corresponding to the non-AP MLD of the received beacon frame, and receiving downlink data on the link with buffer data. For example, the non-AP MLD may determine a bitmap subfield for each link traffic indication bit corresponding to the non-AP MLD receiving the beacon frame according to an AID offset included in the multi-link traffic indication control field in each multi-link traffic indication element, a value of the padding subfield, and a value of the bitmap subfield for each link traffic indication bit; or determining a bit bitmap subfield of each link traffic indication bit corresponding to the non-AP MLD of the received beacon frame according to the AID offset and the AID indication subfield included in the multi-link traffic indication control field in each multi-link traffic indication element.

In the multi-link communication methods shown in fig. 2a to 2c, when one multi-link traffic indication element is used to indicate all the non-AP MLDs with downlink buffered data, the size (e.g., bit length) of the bitmap subfield of each link traffic indication bit corresponding to all the non-AP MLDs is the same, and in fact, the number of links of each non-AP MLD may be very different, so that the indication needs to be performed according to the non-AP MLD with the largest number of links, which results in a large signaling overhead of the multi-link traffic indication element. However, in the embodiment of the present application, all non-AP MLDs to be indicated are scattered through multiple multi-link traffic indication elements, and the size of each link traffic indication bit bitmap subfield in each multi-link traffic indication element is different, so as to save signaling overhead.

In the embodiment of the application, different non-AP MLDs are indicated by segmentation, so that the bit length of the bit map subfield of each link service indication bit corresponding to the non-AP MLDs with less links can be smaller, and the signaling overhead is effectively saved.

Each of the multi-link traffic indication elements in the beacon frame shown in fig. 4a includes a multi-link traffic indication control field including a bit bitmap size subfield, an AID offset subfield, and a reserved subfield, and a per-link traffic indication list field including one or more per-link traffic indication bit bitmap subfields and a padding subfield.

The embodiment of the application also provides a beacon frame, as shown in fig. 4b, each multi-link service indication element in the beacon frame comprises a multi-link service indication control field and a per-link service indication list field, wherein the multi-link service indication control field comprises a link bit map (link bitmap) subfield, an AID offset subfield and a reserved subfield, and the per-link service indication list field comprises one or more per-link service indication bit map subfields and a padding subfield. Fig. 4b differs from fig. 4a in that: the bit map size subfield in fig. 4a is replaced with the link bit map subfield in fig. 4 b. The first subfield includes a link bitmap (link bitmap) subfield, and the link bitmap subfield and the per-link traffic indication bitmap subfield corresponding to the link bitmap subfield may satisfy one or more of the following conditions: condition 1, the bit length of the per-link traffic indication bitmap subfield is equal to the sum of the number of bits for which the link bitmap subfield has a value of 1 (or the sum of the number of bits for which the link bitmap subfield has a value of 0). And (2) the ith bit in the link bit map subfield is used for indicating whether link indication information with the link identification equal to i-1 is included in the per-link service indication bit map subfield, the link indication information is used for indicating whether cache data exists on a corresponding link, and the i is a positive integer. The link corresponding to each bit in the bitmap subfield of the traffic indication bit per link is in turn the same as the link corresponding to the bit with the value of 1 in the bitmap subfield of the traffic indication bit per link (or the link corresponding to each bit in the bitmap subfield of the traffic indication bit per link is in turn the same as the link corresponding to the bit with the value of 0 in the bitmap subfield of the traffic indication bit per link). It may be understood that, in the embodiment of the present application, the bitmap subfield of each link traffic indication bit corresponding to the bitmap subfield of each link refers to that the bitmap subfield of each link bit and the bitmap subfield of each link traffic indication bit are included in the same multi-link traffic indication element.

For example, if the value of the ith bit in the link bitmap subfield is 1, the bitmap subfield includes link indication information with a link identifier equal to i-1. That is, if the value of the i-th bit in the link bitmap subfield is 1, there is one bit in the per-link traffic indication bitmap subfield for indicating whether there is buffered data on the link with the link identification equal to i-1. Of course, the relationship between the link bitmap subfield and the per-link traffic indication bitmap subfield may also be: when the value of the ith bit in the link bit bitmap subfield is 0, the per-link service indication bit bitmap subfield comprises link indication information with the link identification equal to i-1. For convenience of description, the multi-link traffic indication element provided by the embodiment of the present application will be described below by taking the example that the bit of the i-th bit in the bit map subfield of the link bit map has a value of 1, and the bit map subfield of each link traffic indication bit includes link indication information with a link identifier equal to i-1.

Illustratively, the length of the link bitmap subfield is 16 bits or 8 bits, and the ith bit in the link bitmap subfield corresponds to a link id=i-1. For example, when a certain bit in the link bitmap subfield is set to 1, it indicates that the per-link traffic indication bitmap subfield includes an indication of the corresponding link (i.e., corresponds to the bit having the value of 1 in the link bitmap subfield) (i.e., includes link indication information of the corresponding link). Conversely, when a certain bit in the link bitmap subfield is set to 0, it indicates that the per-link traffic indication bitmap subfield does not include an indication of the corresponding link (i.e., does not include link indication information of the corresponding link). It will be appreciated that the length of the link bitmap subfield shown above is only an example, and the length of the link bitmap subfield is not limited by the embodiments of the present application. For example, the length of the link bitmap subfield may also be 10 bits or 12 bits or 15 bits, etc., which are not listed here.

It will be appreciated that the description of the plurality of multi-link traffic indication elements shown in fig. 4b may be referred to above and will not be described in detail here.

The embodiment of the application also provides a beacon frame, as shown in fig. 4c, each multi-link service indication element in the beacon frame comprises a multi-link service indication control field and a per-link service indication list field, wherein the multi-link service indication control field comprises a link offset (link offset) subfield, a bit bitmap size subfield, an AID offset subfield and a reserved subfield, and the per-link service indication list field comprises one or more per-link service indication bit bitmap subfields and a padding subfield. Fig. 4c differs from fig. 4a in that: the multilink traffic indication control field in fig. 4c has been augmented with a link offset quantum field. The link offset sub-field is used for indicating the link ID of the link corresponding to the first bit in the bit map sub-field of each link service indication bit corresponding to the link offset sub-field.

For example, when the value of the link offset subfield is 0110 (e.g., the corresponding link id=6), the bit bitmap size subfield is 0011 (e.g., the corresponding link number is 4), the bit length of the bitmap subfield is 4 per link, and the link identifier corresponding to the first bit in the bitmap subfield is 6 per link, i.e., the bitmap subfield includes link indication information of link id=6 (indicating whether there is cache data on the link of link id=6), link indication information of link id=7, link indication information of link id=8, and link indication information of link id=9. If the first bit bitmap subfield of per link traffic indication carries the following values: 1101, the IDs of links indicating that aid=k of non-AP MLD has buffered data are in order: 6. 7, 9.

The value of the link offset subfield is typically the minimum value of the link identification in the link set to 1 in the per-link traffic indication bit map subfield of the non-AP MLD contained in the multi-link traffic indication element. Of course, the value of the link offset subfield is typically the minimum value-1 of the link identification in the link set to 1 in the per-link traffic indication bit map subfield of the non-AP MLD contained in the multi-link traffic indication element. That is, the value of the link offset quantum field may be floating (e.g., 1 value, 2 values, etc.) around the minimum value described above, which is not limited by embodiments of the present application. In practice, the value of the link offset subfield is also allowed to be smaller than the minimum value of the link identification in the link set to 1 in the per-link traffic indication bit map subfield of the non-AP MLD contained in the multi-link traffic indication element, for example.

It will be appreciated that in the various implementations shown above, where one implementation is not described in detail, reference may also be made to other implementations. Meanwhile, the above-described implementations may be combined with each other, and will not be described in detail.

The following describes a communication device provided by an embodiment of the present application.

According to the method embodiment of the application, the communication device is divided into the functional modules, for example, each functional module can be divided corresponding to each function, and two or more functions can be integrated into one processing module. The integrated modules may be implemented in hardware or in software functional modules. It should be noted that, the division of the modules in the present application is illustrative, and is merely a logic function division, and other division manners may be implemented in practice. The communication device according to the embodiment of the present application will be described in detail with reference to fig. 6 to 8.

Fig. 6 is a schematic structural diagram of a communication device according to an embodiment of the present application, and as shown in fig. 6, the communication device includes a processing unit 601 and a transceiver unit 602.

In some embodiments of the application, the communication device may be an AP or AP MLD or chip as shown above, which may be applied to an AP or AP MLD, etc. I.e. the communication device may be adapted to perform the steps or functions etc. performed by the first communication device in the above method embodiments.

A processing unit 601, configured to generate a beacon frame; a transceiver 602 for outputting the beacon frame.

It should be understood that the specific descriptions of the transceiver unit and the processing unit shown in the embodiments of the present application are only examples, and reference may be made to the above method embodiments for specific functions or steps performed by the transceiver unit and the processing unit, which are not described in detail herein. Illustratively, the processing unit 601 may be configured to perform the step 301 shown in fig. 3, and the transceiver unit 602 may be configured to perform the transmitting step of the step 302 shown in fig. 3.

Multiplexing fig. 6, in other embodiments of the present application, the communication device may be the STA or non-AP MLD or chip shown above, which may be applied to the STA or non-AP MLD. I.e. the communication device may be adapted to perform the steps or functions etc. performed by the second communication device in the above method embodiments.

Such as a transceiver 602, for inputting beacon frames; the processing unit 601 is configured to input downlink data on a link with buffered data according to the beacon frame.

Illustratively, the processing unit 601 is further configured to determine a link with buffered data based on the beacon frame.

The processing unit 601 is specifically configured to determine a multi-link traffic indication element corresponding to the non-AP MLD of the received beacon frame and/or a bit map subfield of each link traffic indication bit corresponding to the non-AP MLD of the received beacon frame according to an AID offset included in the multi-link traffic indication control field in each multi-link traffic indication element; determining a link corresponding to each bit in each link traffic indication bit map subfield corresponding to the non-AP MLD of the received beacon frame according to the bit map size subfield included in the multi-link traffic indication control field in the multi-link traffic indication element corresponding to the non-AP MLD of the received beacon frame; and determining the link with the cached data according to the value of each bit in the bit map subfield of each link traffic indication bit corresponding to the non-AP MLD of the received beacon frame.

The processing unit 601 is specifically configured to determine a bitmap subfield of each link traffic indication bit corresponding to a non-AP MLD of the received beacon frame according to an AID offset included in a control field of each multi-link traffic indication in each multi-link traffic indication element, a value of a padding subfield, and a value of a bitmap subfield of each link traffic indication bit; or determining a bit bitmap subfield of each link traffic indication bit corresponding to the non-AP MLD of the received beacon frame according to the AID offset and the AID indication subfield included in the multi-link traffic indication control field in each multi-link traffic indication element.

It should be understood that the specific descriptions of the transceiver unit and the processing unit shown in the embodiments of the present application are only examples, and reference may be made to the above method embodiments for specific functions or steps performed by the transceiver unit and the processing unit, which are not described in detail herein. Illustratively, the transceiver unit 602 may be further configured to perform the receiving step of step 302 shown in fig. 3, and the processing unit 601 may be further configured to perform step 303 shown in fig. 3.

In the above embodiments, the description of the multi-link traffic indication element, the TIM element, the multi-link traffic indication control field, the per-link traffic indication list field, the per-link traffic indication bit bitmap subfield, the partial virtual bit bitmap field, and the like, which are referred to in the beacon frame, may also refer to the description in the above method embodiments (e.g., fig. 2a to 2c, fig. 3, fig. 4a to 4c, fig. 5), which are not described in detail herein.

The first communication device and the second communication device according to the embodiments of the present application are described above, and possible product forms of the first communication device and the second communication device are described below. It should be understood that any product having the function of the first communication device described in fig. 6, or any product having the function of the second communication device described in fig. 6 falls within the scope of the embodiments of the present application. It should also be understood that the following description is only exemplary, and not limiting the product forms of the first communication device and the second communication device according to the embodiments of the present application.

In a possible implementation, in the communication apparatus shown in fig. 6, the processing unit 601 may be one or more processors, the transceiver unit 602 may be a transceiver, or the transceiver unit 602 may also be a transmitting unit and a receiving unit, the transmitting unit may be a transmitter, and the receiving unit may be a receiver, where the transmitting unit and the receiving unit are integrated into one device, such as a transceiver. In the embodiment of the present application, the processor and the transceiver may be coupled, etc., and the embodiment of the present application is not limited to the connection manner of the processor and the transceiver. In performing the above method, the process of transmitting information (e.g., transmitting a beacon frame) in the above method may be understood as a process of outputting the above information by a processor. When outputting the information, the processor outputs the information to the transceiver for transmission by the transceiver. This information, after being output by the processor, may also require additional processing before reaching the transceiver. Similarly, the process of receiving information (e.g., receiving a beacon frame) in the above method may be understood as a process in which a processor receives the input of the above information. When the processor receives the input information, the transceiver receives the information and inputs it to the processor. Further, after the transceiver receives the information, the information may need to be further processed before being input to the processor.

As shown in fig. 7, the communication device 70 includes one or more processors 720 and a transceiver 710.

Illustratively, the processor 720, when the communication device is configured to perform the steps or methods or functions performed by the first communication device described above, is configured to generate a beacon frame; a transceiver 710 for transmitting the beacon frame to the second communication device.

Illustratively, when the communication device is configured to perform the steps or methods or functions performed by the second communication device described above, the transceiver 710 is configured to receive a beacon frame from the first communication device; a processor 720 for receiving downlink data on the link with the buffered data according to the beacon frame.

In various implementations of the communication device shown in fig. 7, the transceiver may include a receiver to perform the functions (or operations) of receiving and a transmitter to perform the functions (or operations) of transmitting. And transceivers are used to communicate with other devices/means via transmission media.

Optionally, the communication device 70 may also include one or more memories 730 for storing program instructions and/or data, etc. Memory 730 is coupled to processor 720. The coupling in the embodiments of the present application is an indirect coupling or communication connection between devices, units, or modules, which may be in electrical, mechanical, or other forms for information interaction between the devices, units, or modules. Processor 720 may operate in conjunction with memory 730. Processor 720 may execute program instructions stored in memory 730. In the alternative, at least one of the one or more memories may be included in the processor.

The specific connection medium between the transceiver 710, the processor 720, and the memory 730 is not limited in the embodiment of the present application. In the embodiment of the present application, the memory 730, the processor 720 and the transceiver 710 are connected through the bus 740 in fig. 7, and the bus is shown by a thick line in fig. 7, and the connection manner between other components is only schematically illustrated, but not limited thereto. The buses may be classified as address buses, data buses, control buses, etc. For ease of illustration, only one thick line is shown in fig. 7, but not only one bus or one type of bus.

In the embodiment of the present application, the processor may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or the like, and may implement or execute the methods, steps, and logic blocks disclosed in the embodiment of the present application. The general purpose processor may be a microprocessor or any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in the processor for execution, etc.

In an embodiment of the present application, the Memory may include, but is not limited to, nonvolatile Memory such as Hard Disk Drive (HDD) or Solid State Drive (SSD), random access Memory (Random Access Memory, RAM), erasable programmable Read-Only Memory (Erasable Programmable ROM, EPROM), read-Only Memory (ROM), portable Read-Only Memory (Compact Disc Read-Only Memory, CD-ROM), etc. The memory is any storage medium that can be used to carry or store program code in the form of instructions or data structures and that can be read and/or written by a computer (e.g., a communication device, etc., as illustrated by the present application), but is not limited thereto. The memory in embodiments of the present application may also be circuitry or any other device capable of performing memory functions for storing program instructions and/or data.

The processor 720 is mainly used for processing communication protocols and communication data, controlling the whole communication device, executing software programs and processing data of the software programs. Memory 730 is primarily used to store software programs and data. The transceiver 710 may include control circuitry for primarily converting baseband signals to radio frequency signals and processing the radio frequency signals, and an antenna. The antenna is mainly used for receiving and transmitting radio frequency signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc., are mainly used for receiving data input by a user and outputting data to the user.

When the communication device is powered on, the processor 720 may read the software program in the memory 730, interpret and execute instructions of the software program, and process data of the software program. When data is required to be transmitted wirelessly, the processor 720 performs baseband processing on the data to be transmitted, and then outputs a baseband signal to the radio frequency circuit, and the radio frequency circuit performs radio frequency processing on the baseband signal and then transmits the radio frequency signal outwards in the form of electromagnetic waves through the antenna. When data is transmitted to the communication device, the radio frequency circuit receives a radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 720, and the processor 720 converts the baseband signal into data and processes the data.

In another implementation, the radio frequency circuitry and antenna may be provided separately from the processor performing the baseband processing, e.g., in a distributed scenario, the radio frequency circuitry and antenna may be in a remote arrangement from the communication device.

It will be appreciated that the communication device shown in the embodiment of the present application may also have more components than those shown in fig. 7, and the embodiment of the present application is not limited thereto. The methods performed by the processors and transceivers shown above are merely examples, and reference is made to the methods described above for specific steps performed by the processors and transceivers.

In another possible implementation, in the communications apparatus shown in fig. 6, the processing unit 601 may be one or more logic circuits, and the transceiver unit 602 may be an input-output interface, which is also referred to as a communications interface, or an interface circuit, or an interface, or the like. Alternatively, the transceiver unit 602 may be a transmitting unit and a receiving unit, where the transmitting unit may be an output interface and the receiving unit may be an input interface, and the transmitting unit and the receiving unit are integrated into one unit, for example, the input/output interface. As shown in fig. 8, the communication apparatus shown in fig. 8 includes a logic circuit 801 and an interface 802. That is, the processing unit 601 may be implemented by the logic circuit 801, and the transceiver unit 602 may be implemented by the interface 802. The logic circuit 801 may be a chip, a processing circuit, an integrated circuit, or a system on chip (SoC) chip, and the interface 802 may be a communication interface, an input/output interface, a pin, or the like. Fig. 8 exemplifies the communication device described above as a chip including a logic circuit 801 and an interface 802.

In the embodiment of the application, the logic circuit and the interface can be coupled with each other. The embodiment of the present application is not limited to the specific connection manner of the logic circuit and the interface.

Illustratively, when the communication device is configured to perform a method or function or step performed by the first communication device described above, the logic 801 is configured to generate a beacon frame; an interface 802 for outputting the beacon frame.

Illustratively, when the communication device is configured to perform a method or function or step performed by the second communication device described above, the interface 802 is configured to input a beacon frame; logic 801 for receiving downstream data on a link with buffered data according to a beacon frame. It will be appreciated that logic 801 is also operative to determine a link with buffered data from the beacon frame.

It may be understood that the communication device shown in the embodiment of the present application may implement the method provided in the embodiment of the present application in a hardware manner, or may implement the method provided in the embodiment of the present application in a software manner, which is not limited to this embodiment of the present application.

Reference may also be made to the above embodiments for a specific implementation of the embodiments shown in fig. 8, which are not described in detail herein.

The embodiment of the application also provides a wireless communication system, which comprises a first communication device and a second communication device, wherein the first communication device and the second communication device can be used for executing the method in any of the previous embodiments (such as fig. 3).

Furthermore, the present application provides a computer program for implementing the operations and/or processes performed by the first communication device in the method provided by the present application.

The present application also provides a computer program for implementing the operations and/or processes performed by the second communication device in the method provided by the present application.

The present application also provides a computer readable storage medium having computer code stored therein which, when run on a computer, causes the computer to perform the operations and/or processes performed by the first communication device in the method provided by the present application.

The present application also provides a computer readable storage medium having computer code stored therein which, when run on a computer, causes the computer to perform the operations and/or processes performed by the second communication device in the method provided by the present application.

The present application also provides a computer program product comprising computer code or a computer program which, when run on a computer, causes the operations and/or processes performed by the first communication device in the method provided by the present application to be performed.

The present application also provides a computer program product comprising computer code or a computer program which, when run on a computer, causes the operations and/or processes performed by the second communication device in the method provided by the present application to be performed.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. In addition, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices, or elements, or may be an electrical, mechanical, or other form of connection.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the technical effects of the scheme provided by the embodiment of the application.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application is essentially or a part contributing to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a readable storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application. And the aforementioned readable storage medium includes: a U-disk, a removable hard disk, a read-only memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of multilink communication, the method comprising:

generating a beacon frame, wherein the beacon frame comprises a plurality of multilink service indication elements, and each multilink service indication element in the multilink service indication elements is used for indicating whether corresponding non-access point multilink equipment (non-AP) MLD) has cache data on one or more links;

and transmitting the beacon frame.

2. A method of multilink communication, the method comprising:

receiving a beacon frame, wherein the beacon frame comprises a plurality of multilink service indication elements, and each multilink service indication element in the multilink service indication elements is used for indicating whether corresponding non-access point multilink equipment (non-AP) MLD) has cache data on one or more links;

And receiving downlink data on a link with the buffer data according to the beacon frame.

3. The method according to claim 1 or 2, wherein the multi-link traffic indication element comprises a per-link traffic indication list field, the per-link traffic indication list field comprising a padding subfield and one or more per-link traffic indication bit map subfields, each bit in the per-link traffic indication bit map subfields being used for indicating whether there is buffered data on a corresponding link, at least one bit in the per-link traffic indication bit map subfields having a value of 1, and all bits in the padding subfields having a value of 0;

the padding subfield is located after the bitmap subfield of each link traffic indication bit, and the value of all bits of the padding subfield is 0 to distinguish the padding subfield from the bitmap subfield of each link traffic indication bit, or the value of all bits of the padding subfield is 0 to indicate that the non-AP MLD receiving the beacon frame finishes parsing the bitmap field of each link traffic indication list.

4. The method of claim 1 or 2, wherein the multi-link traffic indication element comprises a per-link traffic indication list field comprising one or more per-link traffic indication bit bitmap subfields, each bit in the per-link traffic indication bit bitmap subfields being used to indicate whether there is buffered data on a corresponding link, and wherein a bit length of the per-link traffic indication bit bitmap subfields is greater than or equal to a sum of link numbers associated with non-AP MLDs corresponding to the per-link traffic indication bit bitmap subfields.

5. The method of any of claims 1-4, wherein the beacon frame further comprises a traffic indication map, TIM, element, the TIM element comprising a partial virtual bit map field for indicating AIDs corresponding to the plurality of multilink traffic indication elements;

the multi-link service indication element comprises a multi-link service indication control field and a per-link service indication list field, the multi-link service indication control field comprises an associated identification AID offset sub-field, the per-link service indication list field comprises one or more per-link service indication bit bitmap subfields, and the AID offset sub-field is used for indicating AIDs corresponding to a first one of the one or more per-link service indication bit bitmap subfields.

6. The method of claim 5, wherein the multi-link traffic indication control field further comprises an AID indication subfield, the AID offset subfield and the AID indication subfield being used to indicate an AID for each of the one or more per-link traffic indication bit map subfields.

7. The method of claim 6, wherein the AID indication subfield is configured to indicate a length of an AID corresponding to the one or more per-link traffic indication bit map subfields; or,

the AID indication subfield is configured to indicate an AID corresponding to a last one of the one or more bitmap subfields; or,

the AID indication subfield is used for indicating the number of the bit map subfields of the per-link service indication bit.

8. The method of any of claims 5-7, wherein each of the plurality of multilink traffic indication elements corresponds to a portion of non-AP MLDs of the buffered data indicated by the portion virtual bit map field.

9. The method according to any of claims 2-8, wherein the receiving downlink data on the link with buffered data according to the beacon frame comprises:

determining a multi-link service indication element corresponding to a non-AP MLD for receiving the beacon frame and/or a bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame according to the AID offset included in the multi-link service indication control field in each multi-link service indication element, wherein the bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame is contained in the multi-link service indication element corresponding to the non-AP MLD for receiving the beacon frame;

Determining a link corresponding to each bit in each link traffic indication bit map subfield corresponding to the non-AP MLD receiving the beacon frame according to a bit map size subfield included in a multi-link traffic indication control field in a multi-link traffic indication element corresponding to the non-AP MLD receiving the beacon frame;

and determining a link with buffer data according to the value of each bit in the bit map subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame, and receiving downlink data on the link with the buffer data.

10. The method of claim 9, wherein the determining the multi-link traffic indication element corresponding to the non-AP MLD receiving the beacon frame and/or the per-link traffic indication bit bitmap subfield corresponding to the non-AP MLD receiving the beacon frame according to the AID offset included in the multi-link traffic indication control field in each multi-link traffic indication element comprises:

determining a bit bitmap subfield of each link service indication bit corresponding to a non-AP MLD receiving the beacon frame according to the AID offset included in the control field of each link service indication element, the value of the filling subfield and the value of the bit bitmap subfield of each link service indication bit; or,

And determining a bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame according to the AID offset included in the multilink service indication control field in each multilink service indication element and the AID indication subfield.

11. A communication device, the device comprising:

a processing unit, configured to generate a beacon frame, where the beacon frame includes a plurality of multilink traffic indication elements, where each multilink traffic indication element in the plurality of multilink traffic indication elements is configured to indicate whether a corresponding non-access point multilink device non-AP MLD has buffered data on one or more links;

and the receiving and transmitting unit is used for transmitting the beacon frame.

12. A communications apparatus comprising a non-access point multilink device non-AP MLD, the apparatus comprising:

a transceiver unit, configured to receive a beacon frame, where the beacon frame includes a plurality of multilink service indication elements, where each multilink service indication element in the plurality of multilink service indication elements is configured to indicate whether a corresponding non-access point multilink device non-AP MLD has buffered data on one or more links;

And the processing unit is used for receiving downlink data on the link with the buffer data according to the beacon frame.

13. The apparatus according to claim 11 or 12, wherein the multi-link traffic indication element comprises a per-link traffic indication list field, the per-link traffic indication list field comprising a padding subfield and one or more per-link traffic indication bit map subfields, each bit in the per-link traffic indication bit map subfields being used to indicate whether there is buffered data on a corresponding link, at least one bit in the per-link traffic indication bit map subfields having a value of 1, and all bits in the padding subfields having a value of 0;

14. The apparatus of claim 11 or 12, wherein the multi-link traffic indication element comprises a per-link traffic indication list field comprising one or more per-link traffic indication bit bitmap subfields, each bit in the per-link traffic indication bit bitmap subfields being used to indicate whether there is buffered data on a corresponding link, and wherein a bit length of the per-link traffic indication bit bitmap subfields is greater than or equal to a sum of link numbers associated with non-AP MLDs corresponding to the per-link traffic indication bit bitmap subfields.

15. The apparatus according to any one of claims 11-14, wherein the beacon frame further comprises a traffic indication map, TIM, element, the TIM element comprising a partial virtual bit map field for indicating AIDs corresponding to the plurality of multilink traffic indication elements;

16. The apparatus of claim 15, wherein the multi-link traffic indication control field further comprises an AID indication subfield, the AID offset subfield and the AID indication subfield to indicate an AID for each of the one or more per-link traffic indication bit map subfields.

17. The apparatus of claim 16, wherein the AID indication subfield is to indicate a length of an AID corresponding to the one or more per-link traffic indication bit map subfields; or,

18. The apparatus of any of claims 15-17, wherein each of the plurality of multilink traffic indication elements corresponds to a portion of non-AP MLDs of the non-AP MLDs with buffered data indicated by the portion virtual bit map field.

19. The apparatus according to any of claims 12-18, wherein the processing unit is specifically configured to determine, according to an AID offset included in a multilink traffic indication control field in each multilink traffic indication element, a multilink traffic indication element corresponding to a non-AP MLD receiving the beacon frame and/or a per-link traffic indication bit bitmap subfield corresponding to a non-AP MLD receiving the beacon frame, the per-link traffic indication bit bitmap subfield corresponding to the non-AP MLD receiving the beacon frame being included in the multilink traffic indication element corresponding to the non-AP MLD receiving the beacon frame; determining a link corresponding to each bit in each link traffic indication bit map subfield corresponding to the non-AP MLD receiving the beacon frame according to a bit map size subfield included in a multi-link traffic indication control field in a multi-link traffic indication element corresponding to the non-AP MLD receiving the beacon frame; and determining a link with buffer data according to the value of each bit in the bit map subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame, and receiving downlink data on the link with the buffer data.

20. The apparatus of claim 19, wherein the processing unit is specifically configured to determine a bitmap subfield for each link traffic indication bit corresponding to a non-AP MLD receiving the beacon frame according to an AID offset included in a control field for the multi-link traffic indication in each multi-link traffic indication element, the value of the padding subfield, and the value of the bitmap subfield for each link traffic indication bit; or determining a bit bitmap subfield of each link service indication bit corresponding to the non-AP MLD for receiving the beacon frame according to the AID offset included in the multilink service indication control field in each multilink service indication element and the AID indication subfield.

21. A communication device comprising a processor and a memory;

the memory is used for storing instructions;

the processor is configured to execute the instructions to cause the method of any one of claims 1 to 10 to be performed.

22. A communication device comprising logic circuitry and an interface, the logic circuitry and interface coupled;

the interface being for inputting and/or outputting code instructions, the logic circuitry being for executing the code instructions to cause the method of any of claims 1 to 10 to be performed.

23. A computer readable storage medium, characterized in that the computer readable storage medium is for storing a computer program which, when executed, is adapted to carry out the method of any one of claims 1 to 10.