Multicast feedback method, device and system

Abstract

The present application relates to the field of wireless fidelity WIFI technology, and in particular to a multicast feedback method, device and system, which can realize the sending feedback in a multicast transmission scenario. In the method, the access point sends a multicast data frame and a multicast feedback trigger frame, and the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly. After the first site receives the multicast data frame and the multicast feedback trigger frame, if the first site is a site scheduled by the multicast feedback trigger frame, and the first site does not correctly decode the multicast data frame, a multicast feedback report frame is sent on the second subcarrier, and accordingly, when the access point detects energy on the second subcarrier, it is determined that the first site has not correctly decoded the multicast data frame; or, the multicast feedback report frame is not sent on both the first subcarrier and the second subcarrier, and accordingly, when the access point does not detect energy on both the first subcarrier and the second subcarrier, it is determined that the first site has not correctly decoded the multicast data frame.

Description

Technical Field

[0001] The present application relates to the field of wireless fidelity technology, and in particular to a multicast feedback method, device and system. Background Art

[0002] The typical transmission model of wireless local area network (WLAN) is point-to-point unicast transmission mode. When the wireless channel quality is unstable due to factors such as small-scale fast fading, occlusion and shadow fading, and co-channel interference, the access point (AP) in the unicast transmission mode can obtain the link quality status of the channel through the response feedback of the station (STA), so that it can retransmit according to the link quality status or adjust the modulation and coding scheme (MCS) to achieve rate adaptation.

[0003] With the rapid development and widespread application of WLAN technology, new services such as video conferencing, virtual reality teaching, and electronic schoolbags have gradually emerged. These services usually have the characteristics of large capacity and high user density. For these new services, in order to improve the utilization efficiency of spectrum resources and alleviate the contradiction between the high throughput performance requirements of the network and the shortage of spectrum resources, point-to-multipoint multicast transmission has been widely used.

[0004] In multicast transmission scenarios, there is also the situation of unstable channel quality. In order to ensure transmission reliability, the AP may need to perform rate adaptation or retransmission based on the channel quality status. Therefore, for multicast transmission, it is necessary to design a reasonable feedback mechanism to enable the AP to obtain the channel quality status. Summary of the invention

[0005] The present application provides a multicast feedback method, device and system, which can implement sending feedback in a multicast transmission scenario, so that the access point retransmits or adjusts the rate according to the feedback, thereby improving transmission reliability and transmission efficiency.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions:

[0007] In the first aspect, a multicast feedback method is provided, which can be executed by an access point or by a component of the access point, such as a processor, chip, or chip system of the access point. The present application is described by taking the access point executing the method as an example. The method includes: the access point sends a multicast data frame and a multicast feedback trigger frame, and the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly. Afterwards, when the access point does not detect energy on both the first subcarrier and the second subcarrier, it is determined that the first site has not correctly decoded the multicast data frame; or, when the access point detects energy on the second subcarrier, it is determined that the first site has not correctly decoded the multicast data frame. Among them, the first subcarrier is a subcarrier associated with the first site in the first subcarrier set, the second subcarrier is a subcarrier associated with the first site in the second subcarrier set, and the first site is any one of the multiple sites.

[0008] Based on this solution, the access point schedules the stations in the multicast group to reply to the multicast feedback report frame, and learns whether the stations in the multicast group correctly decode the multicast data frame by detecting energy on the subcarrier associated with the station. Since the access point can determine the stations that did not decode correctly and the stations that decoded correctly in the multicast group, it can retransmit the multicast data frame for the stations that did not decode correctly, thereby improving transmission reliability, or it can also adjust the link rate to improve transmission efficiency.

[0009] In some possible designs, when the multicast data frame is an aggregated media access control protocol data unit AMPDU, the multicast feedback method also includes: the access point sends a block confirmation request trigger frame, and the block confirmation request trigger frame is used to schedule at least one second site to feedback the sequence index of the media access control protocol data unit MPDU with decoding errors in the AMPDU on their respective associated resource units RU, and the second site is a site among multiple sites that does not correctly decode the AMPDU; the access point receives a block confirmation frame from at least one second site on the RU associated with at least one second site, and the block confirmation frame is used to indicate the MPDU with decoding errors in the AMPDU.

[0010] Based on this possible design, when the multicast data frame is AMPDU, the present application provides a two-level feedback mechanism. In the first level of feedback, the access point can first schedule the stations in the multicast group to reply to the multicast feedback report frame through the multicast feedback trigger frame, so as to learn the stations in the multicast group that did not correctly decode the AMPDU. In the second level of feedback, the access point schedules the stations that did not correctly decode the AMPDU through the block confirmation request trigger frame to feedback the sequence number index of the MPDU with decoding error. Thereby, the access point can retransmit the MPDU with decoding error to improve the transmission reliability, or the link rate can be adjusted to improve the transmission efficiency. In addition, the access point filters out the STA with correct decoding through the first level of feedback, so in the second level of feedback, it can avoid allocating RU to the STA with correct decoding, thereby effectively reducing the overhead of the interaction between the block confirmation request trigger frame and the block confirmation frame in the second level of feedback.

[0011] Taking the channel bandwidth of 40MHz as an example, assuming that there are 60 STAs in the multicast group, the number of RUs that can be used to feedback the MPDU with decoding errors is 18. Based on the GCR MU-BAR feedback mechanism in the 802.11ax standard, the AP needs to send 4 MU-BAR trigger frames. Correspondingly, the STAs in the multicast group need to reply with BA frames regardless of whether they decode the AMPDU correctly. Based on the solution of this application, within a certain PER range, the AP only needs to send two block confirmation trigger frames, and the STA that correctly decodes the AMPDU does not need to reply with BA frames, thereby reducing the transmission overhead of the control frame.

[0012] In a second aspect, a multicast feedback method is provided, which can be executed by a first site or by a component of the first site, such as a processor, a chip, or a chip system of the first site. The present application takes the first site executing the method as an example for explanation. The method includes: the first site receives a multicast data frame and a multicast feedback trigger frame from an access point, and the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly; thereafter, when the first site determines that multiple sites include the first site and the first site does not correctly decode the multicast data frame, the first site sends a multicast feedback report frame to the access point on a second subcarrier, and the second subcarrier is a subcarrier in a second subcarrier set associated with the first site.

[0013] In some possible designs, when the multicast data frame is an aggregated media access control protocol data unit AMPDU, the multicast feedback method also includes: the first site receives a block confirmation request trigger frame from the access point, and the block confirmation request trigger frame is used to schedule the first site to feedback the sequence number index of the media access control protocol data unit MPDU with decoding errors in the AMPDU on the resource unit RU associated with the first site; the first site sends a block confirmation frame to the access point on the RU associated with the first site, and the block confirmation frame is used to indicate the MPDU with decoding errors in the AMPDU.

[0014] Among them, the technical effects brought about by any possible design of the second aspect can refer to the technical effects brought about by the corresponding design of the above-mentioned first aspect, and will not be repeated here.

[0015] In combination with the first aspect or the second aspect above, in some possible designs, the multicast feedback trigger frame includes a third field, and the third field is used to indicate a first network allocation vector NAV. The duration of the first NAV is the sum of the following multiple items: the duration of the multicast feedback report frame, the duration of the block confirmation request trigger frame, the duration of the block confirmation frame, and the short frame interval SIFS. The multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

[0016] In combination with the above-mentioned first aspect or second aspect, in some possible designs, the multicast feedback trigger frame includes a third field, and the third field is used to indicate a first network allocation vector NAV. The duration of the first NAV is the sum of the duration of the multicast feedback report frame and the short frame interval SIFS. The multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

[0017] Based on the two possible designs, the access point can protect the channel in the feedback process by indicating the first NAV in the multicast feedback trigger frame, reduce the interference of non-multicast sites on the feedback process, improve feedback efficiency, and reduce feedback delay, so that the access point can retransmit erroneous MPDUs in time, reduce multicast service delays, or adjust the transmission rate in time to improve the multicast service transmission rate.

[0018] In combination with the first aspect or the second aspect above, in some possible designs, the multicast feedback trigger frame includes a first field, and when the value of the first field is a first numerical value, it indicates that the type of the multicast feedback trigger frame is a multicast retransmission confirmation request.

[0019] Based on this possible design, by carrying the first field in the multicast feedback trigger frame, the stations in the multicast group can determine the type of the multicast feedback trigger frame and then provide feedback according to the feedback trigger frame.

[0020] In combination with the above-mentioned first aspect or second aspect, in some possible designs, the multicast feedback trigger frame includes a second field, and the second field is used to indicate a multicast data frame.

[0021] Based on this possible design, by carrying the second field in the multicast feedback trigger frame, the multicast data frame can be clearly indicated, so that the sites in the multicast group can determine whether the multicast data frame indicated by the multicast feedback trigger frame that needs to be fed back is correctly decoded, and thus feedback is provided for the multicast data frame, thereby making the access point and the site have the same understanding of the feedback object, thereby improving the feedback accuracy.

[0022] In combination with the above-mentioned first aspect or second aspect, in some possible designs, the second field includes a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the starting data frame in the multicast data frame, and the second subfield is used to carry the sequence number index of the ending data frame in the multicast data frame.

[0023] In combination with the above-mentioned first aspect or second aspect, in some possible designs, the second field includes a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the starting data frame in the multicast data frame, and the second subfield is used to carry the number of data frames included in the multicast data frame.

[0024] In combination with the above-mentioned first aspect or second aspect, in some possible designs, the second field includes a first subfield and a second subfield, the first subfield is used to carry the number of data frames included in the multicast data frame, and the second subfield is used to carry the sequence number index of the end data frame in the multicast data frame.

[0025] In combination with the first aspect or the second aspect above, in some possible designs, the multicast feedback trigger frame is an empty data packet feedback report polling trigger NFRP frame.

[0026] In a third aspect, a multicast feedback method is provided, which can be executed by an access point or by a component of the access point, such as a processor, a chip, or a chip system of the access point. The present application takes the access point executing the method as an example for explanation. The method includes: the access point sends a multicast data frame and a multicast feedback trigger frame, the multicast feedback trigger frame is used to configure at least one resource unit RU, and the RU is used for sites in the multicast group to transmit a block confirmation frame of the multicast data frame during the uplink orthogonal frequency division multiple access random access UORA process; the access point receives a block confirmation frame from the first site during the UORA process through the first RU, the block confirmation frame is used to indicate a data frame with decoding errors in the multicast data frame, and the first RU is one of the at least one RU configured for the multicast feedback trigger frame.

[0027] Based on this solution, on the one hand, the access point pre-configures at least one RU for feedback of block confirmation frames from multicast sites with decoding errors, thereby obtaining the transmission status of multicast data frames, so as to retransmit data frames with decoding errors in multicast data frames, improve transmission reliability, or adjust the link transmission rate to improve transmission efficiency. On the other hand, in this application, only multicast sites with decoding errors feedback block confirmation frames, and multicast STAs with correct decoding may not provide feedback, thereby reducing the transmission overhead of control frames compared to the traditional GCR MU-BAR feedback method defined in the 802.11ax standard, in which multicast STAs with correct decoding also feedback block confirmation frames.

[0028] In the fourth aspect, a multicast feedback method is provided, which can be executed by a first site, or by a component of the first site, such as a processor, chip, or chip system of the first site. The present application takes the first site executing the method as an example for explanation. The method includes: the first site receives a multicast data frame and a multicast feedback trigger frame from an access point, the multicast feedback trigger frame is used to configure at least one resource unit RU, the RU is used for sites in the multicast group to perform uplink orthogonal frequency division multiple access random access UORA, and the UORA is used to transmit a block confirmation frame of the multicast data frame; when the first site fails to correctly decode the multicast data frame, a block confirmation frame of the multicast data frame is sent to the access point through the first RU during the UORA process, and the block confirmation frame is used to indicate a data frame with a decoding error in the multicast data frame, and the first RU is one of the at least one RU configured for the multicast feedback trigger frame. Among them, the technical effects brought about by the fourth aspect can refer to the technical effects brought about by the third aspect mentioned above, and will not be repeated here.

[0029] In some possible designs, the first site sends a block confirmation frame of a multicast data frame to an access point through a first RU during a UORA process, including: the first site selects a random number in a contention window, and when the random number is less than or equal to the total number of at least one RU configured for a multicast feedback trigger frame, selects a first RU from the at least one RU, and sends a block confirmation frame of the multicast data frame to the access point on the first RU.

[0030] In combination with the third aspect or the fourth aspect above, in some possible designs, the multicast data frame is an aggregated media access control protocol data unit AMPDU, and the data frame is a media access control protocol data unit MPDU.

[0031] In combination with the third aspect or the fourth aspect above, in some possible designs, the multicast feedback trigger frame includes a first field, and when the value of the first field is a first numerical value, it indicates that the type of the multicast feedback trigger frame is uplink orthogonal frequency division multiple access random access-negative response polling.

[0032] In a fifth aspect, a communication device is provided for implementing the various methods described above. The communication device may be the access point described in the first aspect or the third aspect, or a device including the access point, or a device included in the access point, such as a chip; or, the communication device may be the first station described in the second aspect or the fourth aspect, or a device including the first station, or a device included in the first station, such as a chip. The communication device includes a module, unit, or means corresponding to the implementation of the above method, and the module, unit, or means may be implemented by hardware, software, or by executing the corresponding software implementation by hardware. The hardware or software includes one or more modules or units corresponding to the above functions.

[0033] In some possible designs, the communication device may include a processing module and a transceiver module. The transceiver module, which may also be referred to as a transceiver unit, is used to implement the sending and / or receiving functions in any of the above aspects and any possible implementations thereof. The transceiver module may be composed of a transceiver circuit, a transceiver, a transceiver or a communication interface. The processing module may be used to implement the processing functions in any of the above aspects and any possible implementations thereof.

[0034] In some possible designs, the transceiver module includes a sending module and a receiving module, which are respectively used to implement the sending and receiving functions in any of the above aspects and any possible implementation methods thereof.

[0035] Among them, the communication device provided in the fifth aspect is used to execute any one of the above aspects or any possible implementation of any one of the aspects. The specific details can be found in any one of the above aspects or any possible implementation of any one of the aspects, and will not be repeated here.

[0036] In a sixth aspect, a communication device is provided, comprising: a processor and a memory; the memory is used to store computer instructions, and when the processor executes the instructions, the communication device executes the method described in any one of the above aspects. The communication device can be the access point in the above first aspect or the third aspect, or a device including the above access point, or a device included in the above access point, such as a chip; or the communication device can be the first station in the above second aspect or the fourth aspect, or a device including the above first station, or a device included in the above first station, such as a chip.

[0037] In a seventh aspect, a communication device is provided, comprising: a processor and a communication interface; the communication interface is used to communicate with a module outside the communication device; the processor is used to execute a computer program or instruction so that the communication device executes the method described in any of the above aspects. The communication device may be the access point in the above first aspect or the third aspect, or a device including the above access point, or a device included in the above access point, such as a chip; or the communication device may be the first station in the above second aspect or the fourth aspect, or a device including the above first station, or a device included in the above first station, such as a chip.

[0038] In an eighth aspect, a communication device is provided, comprising: an interface circuit and a logic circuit, wherein the interface circuit is used to obtain input information and / or output output information; and the logic circuit is used to execute the method described in any one of the above aspects or any possible implementation of any one of the aspects, and process and / or generate output information according to the input information. The communication device may be the access point in the first or third aspect, or a device including the access point, or a device included in the access point, such as a chip; or the communication device may be the first station in the second or fourth aspect, or a device including the first station, or a device included in the first station, such as a chip.

[0039] When the communication device is the access point in the first aspect, or a device including the access point, or a device included in the access point:

[0040] In some possible designs, the output information may be a multicast data frame and a multicast feedback trigger frame, where the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly.

[0041] In some possible designs, the input information may be: a block confirmation frame of at least one second site, the block confirmation frame being used to indicate an MPDU with a decoding error in the AMPDU. Accordingly, processing according to the input information may be: determining a retransmitted MPDU or a modulated transmission rate according to the block confirmation frame.

[0042] The communication device may be the first site in the second aspect, or a device including the first site, or a device included in the first site:

[0043] In some possible designs, the input information may be: a multicast data frame and a multicast feedback trigger frame, and the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly. Accordingly, processing according to the input information may be: when the multiple sites in the multicast group scheduled by the multicast feedback trigger frame include the first site, and the first site fails to correctly decode the multicast data frame, a multicast feedback report frame is sent to the access point on the second subcarrier, and the second subcarrier is a subcarrier in the second subcarrier set associated with the first site.

[0044] In some possible designs, the output information may be: a block confirmation frame, which is used to indicate an MPDU with a decoding error in the AMPDU.

[0045] When the communication device is the access point in the third aspect, or a device including the access point, or a device included in the access point:

[0046] In some possible designs, the output information may be: multicast data frames and multicast feedback trigger frames, wherein the multicast feedback trigger frames are used to configure at least one resource unit RU, and the RU is used for sites within the multicast group to transmit block confirmation frames of multicast data frames during the uplink orthogonal frequency division multiple access random access UORA process.

[0047] In some possible designs, the input information may be a block confirmation frame, which is used to indicate a data frame with decoding errors in a multicast data frame. Accordingly, processing according to the input information may be: determining a retransmitted data frame or a modulation transmission rate according to the block confirmation frame.

[0048] The communication device may be the first site in the fourth aspect, or a device including the first site, or a device included in the first site:

[0049] In some possible designs, the input information may be: a multicast data frame and a multicast feedback trigger frame, the multicast feedback trigger frame is used to configure at least one resource unit RU, the RU is used for sites in the multicast group to transmit block confirmation frames of multicast data frames during uplink orthogonal frequency division multiple access random access UORA process. Accordingly, processing is performed according to the input information, which may be: when the first site fails to correctly decode the multicast data frame, a block confirmation frame of the multicast data frame is sent to the access point through the first RU during the UORA process, the block confirmation frame is used to indicate a data frame with a decoding error in the multicast data frame, and the first RU is one of the at least one RU configured for the multicast feedback trigger frame.

[0050] In some possible designs, the output information may be: a block confirmation frame, which is used to indicate a data frame with a decoding error in a multicast data frame.

[0051] In a ninth aspect, a communication device is provided, comprising: at least one processor; the processor is used to execute a computer program or instruction stored in a memory, so that the communication device performs the method described in any one of the above aspects. The memory may be coupled to the processor, or may be independent of the processor. The communication device may be the access point in the first or third aspect, or a device including the access point, or a device included in the access point, such as a chip; or the communication device may be the first station in the second or fourth aspect, or a device including the first station, or a device included in the first station, such as a chip.

[0052] In a tenth aspect, a computer-readable storage medium is provided, wherein instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium is executed on a communication device, the communication device can execute the method described in any one of the above aspects.

[0053] In an eleventh aspect, a computer program product comprising instructions is provided, which, when executed on a communication device, enables the communication device to execute the method described in any one of the above aspects.

[0054] In a twelfth aspect, a communication device (for example, the communication device may be a chip or a chip system) is provided, wherein the communication device includes a processor for implementing the functions involved in any of the above aspects.

[0055] In some possible designs, the communication device includes a memory for storing necessary program instructions and data.

[0056] In some possible designs, when the device is a chip system, it can be composed of a chip or include a chip and other discrete devices.

[0057] It can be understood that when the communication device provided in any one of the fifth to twelfth aspects is a chip, the above-mentioned sending action / function can be understood as output information, and the above-mentioned receiving action / function can be understood as input information.

[0058] Among them, the technical effects brought about by any design method in the fifth to twelfth aspects can refer to the technical effects brought about by different design methods in the above-mentioned first aspect, second aspect, third aspect or fourth aspect, and will not be repeated here.

[0059] In a thirteenth aspect, a communication system is provided, which includes the access point described in the first aspect and the first site described in the second aspect; or, the communication system includes the access point described in the third aspect and the first site described in the fourth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A schematic diagram of the structure of a communication system provided for this application;

[0061] Figure 2 A network architecture diagram of a multi-link communication provided for this application;

[0062] Figure 3 A schematic diagram of the structure of a WLAN device provided in this application;

[0063] Figure 4 A schematic diagram of the structure of the user information field of an NFRP frame provided by this application;

[0064] Figure 5 A schematic diagram of the frame structure of an NDP feedback report response frame provided in this application;

[0065] Figure 6 A schematic diagram of setting a network allocation vector NAV provided in this application;

[0066] Figure 7a A schematic diagram of unicast transmission provided for this application;

[0067] Figure 7b A schematic diagram of multicast transmission provided for this application;

[0068] Figure 8 A schematic diagram of a multicast feedback process based on a BAR frame provided in this application;

[0069] Fig. 9 A schematic diagram of a multicast feedback process based on MU-BAR frames provided in this application;

[0070] Fig.10 A flowchart of a multicast feedback method provided in this application;

[0071] Fig.11a A schematic diagram of a local frame structure of a multicast feedback trigger frame provided in this application;

[0072] Fig.11b A schematic diagram of a partial frame structure of another multicast feedback trigger frame provided in this application;

[0073] Fig.12 A flowchart of another multicast feedback method provided by this application;

[0074] Fig.13 A schematic diagram of a multicast feedback process provided for this application;

[0075] Fig.14 A timing diagram of multicast feedback provided for this application;

[0076] Fig.15 A schematic diagram of a first NAV configuration provided in this application;

[0077] Fig.16 A schematic diagram of another first NAV configuration provided in this application;

[0078] Fig.17 A flowchart of another multicast feedback method provided by this application;

[0079] Fig.18 A schematic diagram of RU distribution provided for this application;

[0080] Fig.19 A schematic diagram of a partial frame structure of another multicast feedback trigger frame provided in this application;

[0081] Fig. 20 Another multicast feedback process diagram provided for this application;

[0082] Fig.21A schematic diagram of the structure of an access point provided for the application;

[0083] Fig. 22 A schematic diagram of the structure of a first site provided for this application;

[0084] Fig.23 A schematic diagram of the structure of a communication device provided in this application. DETAILED DESCRIPTION

[0085] In the description of this application, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship, for example, A / B can represent A or B; "and / or" in this application is only a kind of association relationship describing the associated objects, indicating that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In addition, in the description of this application, unless otherwise specified, "multiple" refers to two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, a and b, a and c, b and c, a and b and c, where a, b, c can be single or multiple. In addition, in order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "first" and "second" are used to distinguish the same items or similar items with substantially the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit the difference.

[0086] It should be noted that, in this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0087] The embodiments of the present application may be applicable to wireless local area network (WLAN) scenarios, and may be applicable to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 system standards, such as 802.11a / b / g standards, 802.11n standards, 802.11ac standards, 802.11ax standards, or their next generation, such as 802.11be standards or even later generation standards. Alternatively, the embodiments of the present application may also be applicable to wireless local area network systems such as the Internet of Things (IoT) network or the Vehicle to X (V2X) network. Of course, the embodiments of the present application can also be applied to other possible communication systems, such as long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, and future fifth generation (5G) communication system, etc.

[0088] First, the present application provides a WLAN communication system applicable to an embodiment of the present application, the WLAN communication system comprising at least one wireless access point (access point, AP), and multiple stations (stations, STAs) associated with the AP. It should be noted that the STA involved in the embodiment of the present application can also be called a terminal, and the two can be replaced with each other, and the method provided in the present application does not specifically limit this.

[0089] As an example, see Figure 1 , showing an architecture diagram of the WLAN communication system provided in the present application. Figure 1For example, the WLAN includes an AP, and the AP is associated with STA1, STA2, STA3, STA4, and STA5. The AP can schedule wireless resources for the STAs associated with it and / or unassociated STAs, and transmit data to the STAs on the scheduled wireless resources. For example, the AP can schedule wireless resources for STA1, STA2, STA3, STA4, and STA5, and transmit data, including uplink data information and / or downlink data information, to STA1, STA2, STA3, STA4, and STA5 on the scheduled wireless resources.

[0090] In addition, the embodiments of the present application may be applicable to communications between AP and STA, for example, multicast communications between AP and STA1, STA2, and STA3, and unicast communications between AP and STA4 or STA5; and may also be applicable to communications between STA and STA, for example, communications between STA4 and STA5. And the AP and STA in the embodiments of the present application may be wireless communication devices that support parallel transmission of multiple links. For example, they are called multi-link devices (MLD) or multi-band devices (MBD), which have higher transmission efficiency and higher throughput. In this article, an AP that supports multi-link communications may be referred to as an MLD AP, and a STA that supports multi-link communications, namely a multi-link STA, may be referred to as a non-Access Point Station (non-AP STA). It should be understood that Figure 1 The number of APs and STAs is just an example and can be more or less.

[0091] See also Figure 2 , is a network architecture diagram of a multi-link communication provided by an embodiment of the present application. It illustrates that a multi-link device in a wireless local area network communicates with other devices through multiple links, such as Figure 2 A schematic diagram of communication between a multi-link AP device 101 and a multi-link STA 102 is shown. The multi-link AP device 101 includes subordinate AP101-1 and AP101-2, and the multi-link STA 102 includes subordinate STA102-1 and STA102-2. The multi-link AP device 101 and the multi-link STA 102 use link 1 and link 2 for parallel communication.

[0092] The multi-link device in the embodiment of the present application can be a single-antenna device or a multi-antenna device. For example, it can be a device with more than two antennas. The embodiment of the present application does not limit the number of antennas included in the multi-link device. In the embodiment of the present application, the multi-link device can allow services of the same access type to be transmitted on different links, and even allow the same data packets to be transmitted on different links; it can also not allow services of the same access type to be transmitted on different links, but allow services of different access types to be transmitted on different links. The frequency bands in which the multi-link device can operate include: sub 1GHz, 2.4GHz, 5GHz, 6GHz and high frequency 60GHz.

[0093] The STA involved in the embodiments of the present application may be a wireless communication chip, a wireless sensor or a wireless communication terminal. For example, a user terminal, a user device, an access device, a subscriber station, a subscriber unit, a mobile station, a user agent, and a user equipment that support wireless fidelity (WiFi) communication functions, wherein the user terminal may include various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices, Internet of Things (IoT) devices, computing devices, or other processing devices connected to a wireless modem, as well as various forms of user equipment (UE), mobile station (MS), terminal, terminal equipment, portable communication devices, handheld devices, portable computing devices, entertainment devices, gaming devices or systems, global positioning system devices, or any other suitable devices configured to communicate over a wireless medium. In addition, the STA may support the 802.11be standard. STA can also support multiple WLAN standards such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b and 802.11a.

[0094] The AP involved in the embodiment of the present application can be a device deployed in a wireless communication network to provide wireless communication functions for its associated STA. It is mainly deployed in homes, buildings and parks, with a typical coverage radius of tens of meters to hundreds of meters. Of course, it can also be deployed outdoors. AP is equivalent to a bridge connecting wired networks and wireless networks. Its main function is to connect various wireless network clients together and then connect the wireless network to Ethernet. Specifically, AP can be a communication device such as a base station, router, gateway, repeater, communication server, switch or bridge with a WiFi chip, wherein the base station can include various forms of macro base stations, micro base stations, relay stations, etc. In addition, AP can support 802.11be standard. AP can also support WLAN standards such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b and 802.11a.

[0095] In some embodiments, the AP and STA involved in the present application may be collectively referred to as WLAN devices. In specific implementation, the WLAN device may adopt Figure 3 The structure shown, or including Figure 3 Parts shown.

[0096] See also Figure 3 , is a schematic diagram of the composition of a WLAN device 300 provided in an embodiment of the present application. The WLAN device 300 may be a STA or a chip or a chip system (or a system on a chip) in a STA; it may also be an AP or a chip or a chip system (or a system on a chip) in an AP. In the embodiment of the present application, the chip system may be composed of a chip, or may include a chip and other discrete devices.

[0097] like Figure 3 As shown, the WLAN device 300 includes a processor 301, a transceiver 302 and a communication line 303. Further, the WLAN device 300 may also include a memory 304. The processor 301, the memory 304 and the transceiver 302 may be connected via the communication line 303.

[0098] The processor 301 is a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The processor 301 may also be other devices with processing functions, such as circuits, devices, or software modules, without limitation.

[0099] The transceiver 302 is used to communicate with other devices or other communication networks. The other communication networks may be Ethernet, radio access network (RAN), WLAN, etc. The transceiver 302 may be a module, a circuit, a transceiver or any device capable of achieving communication.

[0100] The communication line 303 is used to transmit information between the components included in the WLAN device 300 .

[0101] The memory 304 is used to store instructions, where the instructions may be computer programs.

[0102] The memory 304 may be a read-only memory (ROM) or other types of static storage devices that can store static information and / or instructions, or a random access memory (RAM) or other types of dynamic storage devices that can store information and / or instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, etc., without limitation.

[0103] It should be noted that the memory 304 can exist independently of the processor 301, or can be integrated with the processor 301. The memory 304 can be used to store instructions or program codes or some data, etc. The memory 304 can be located in the WLAN device 300, or can be located outside the WLAN device 300, without limitation. The processor 301 is used to execute the instructions stored in the memory 304 to implement the method provided in the following embodiments of the present application.

[0104] In one example, the processor 301 may include one or more CPUs, such as Figure 3 CPU0 and CPU1 in.

[0105] As an optional implementation, the WLAN device 300 includes multiple processors, for example, Figure 3 In addition to the processor 301, a processor 307 may also be included.

[0106] As an optional implementation, the WLAN device 300 further includes an output device 305 and an input device 306. Exemplarily, the input device 306 is a keyboard, a mouse, a microphone, a joystick, and the like, and the output device 305 is a display screen, a speaker, and the like.

[0107] Understandably, Figure 3 The components shown in the figure do not constitute a limitation on the WLAN device. Figure 3 In addition to the components shown, the WLAN device may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0108] The WLAN communication system and WLAN device provided by the present application are introduced above. To facilitate understanding of the technical solutions of the embodiments of the present application, a brief introduction to the related technologies of the present application is given below.

[0109] 1. Null data packet (NDP) feedback (NDP Feedback):

[0110] NDP feedback is an efficient 1-bit feedback mechanism defined in the 802.11ax standard. Currently, the feedback type supported by the NDP feedback mechanism defined in the 802.11ax standard is feedback resource request (RR).

[0111] The basic principle of feedback resource request is as follows: AP sends NDP Feedback Report Poll (NFRP) trigger frame to its associated STA, and the NFRP trigger frame includes information such as initial association identifier (AID), bandwidth, and multiplexing flag. Among them, the initial AID and multiplexing flag information are included in the user information field of the NFRP trigger frame.

[0112] For example, see Figure 4 , which is the format of the user information field of the NFRP trigger frame. The user information field includes an initial 12-bit initial AID (Starting AID) field, a 9-bit reserved field (Reserved), a 4-bit feedback type (Feedback Type) field, a 7-bit reserved field (Reserved), a 7-bit uplink target receive power (ULTarget Receive Power) field, and a 1-bit multiplexing flag field (Multiplexing Flag).

[0113] Among them, the initial AID field indicates the AID of the starting STA scheduled by the AP; the feedback type field indicates the feedback type supported by the current NFRP trigger frame. When the value of this field is 0, it means that the feedback type is a resource request; the uplink target received power indicates the received power of the feedback signal expected by the AP; the multiplexing flag field is used to determine the number of sites scheduled by the AP.

[0114] After receiving the NFRP trigger frame, the STA determines the number of stations scheduled by the AP N_STA based on the bandwidth and multiplexing flag information. If the AID of the STA is greater than or equal to the starting AID and less than the starting AID + N_STA, it means that the STA is scheduled by the AP. Exemplarily, the number of stations scheduled by the AP N_STA satisfies the following formula (1):

[0115] N_STA=18*2 BW *(MultiplexingFlag+1) (1)

[0116] Among them, BW indicates the channel bandwidth, for example, BW equals 0, indicating that the channel bandwidth is 20MHz, BW equals 1, indicating that the channel bandwidth is 40MHz, BW equals 2, indicating that the channel bandwidth is 80MHz, BW equals 3, indicating that the channel bandwidth is 80+80MHz, or 160MHz; MultiplexingFlag is the value of the multiplexing flag field in the NFRP trigger frame.

[0117] The scheduled STA decides whether to send an NDP feedback report response (NFRR) frame to the AP based on whether it has data to be sent. For example, when the scheduled STA has no data to be sent, it does not send an NDP feedback report response frame, or when the scheduled STA has data to be sent, it sends an NDP feedback report response frame.

[0118] Specifically, in the 802.11ax standard, the frame structure of the NDP feedback report response frame is similar to the frame structure of the high-efficiency (HE) trigger-based (TB) physical layer protocol data unit (PPDU) (ie, HE TB PPDU), with the difference that the NDP feedback report response frame does not include a data field, and the duration of the data packet extension (PE) field is 0 microseconds (us).

[0119] Exemplarily, the frame structure of the NDP feedback report response frame is as follows: Figure 5As shown, including: legacy short training field (L-STF), legacy long training field (L-LTF), legacy signaling field (L-SIG), repeated legacy signaling field (RL-SIG), high efficient signaling field A (HE-SIG A), high efficient short training field (HE-STF), high efficient long training field (HE-LTF), data packet extension (PE), the duration of PE is 0us, which can also be understood as the NDP feedback report response frame does not include PE.

[0120] Before sending the NFRP trigger frame, the AP will configure two subcarrier sets, NDP_TONE_SET_0 and NDP_TONE_SET_1, to the STAs scheduled by it through broadcast frames. Each STA scheduled by the AP has an associated subcarrier in NDP_TONE_SET_0 and an associated subcarrier in NDP_TONE_SET_1, which are used for the scheduled STA to send NDP feedback report response frames.

[0121] For example, taking the case where the STAs scheduled by the AP include STA1, STA2, and STA3, the NDP_TONE_SET_0 may include subcarrier 11 associated with STA1, subcarrier 21 associated with STA2, and subcarrier 31 associated with STA3; the NDP_TONE_SET_1 may include subcarrier 12 associated with STA1, subcarrier 22 associated with STA2, and subcarrier 32 associated with STA3.

[0122] When the scheduled STA has data to be sent, it can send an NDP feedback report response frame to the AP on the subcarrier associated with it in NDP_TONE_SET_0, indicating that the RR fed back by the STA is between 1 and the RR cache threshold. In this scenario, the feedback state of the NDP feedback report response frame can be considered to be state 0; or, it can send an NDP feedback report response frame to the AP on the subcarrier associated with it in NDP_TONE_SET_1, indicating that the RR fed back by the STA is greater than the RR cache threshold. In this scenario, the feedback state of the NDP feedback report response frame can be considered to be state 1.

[0123] Exemplarily, when STA1 scheduled by the AP has data to be sent, if the RR determined by the STA is between 1 and the RR cache threshold, STA1 sends an NDP feedback report response frame to the AP on subcarrier 11 in NDP_TONE_SET_0; if the RR determined by the STA is greater than the RR cache threshold, STA1 sends an NDP feedback report response frame to the AP on subcarrier 12 in NDP_TONE_SET_1.

[0124] 2. Uplink OFDMA random access (UL OFDMA-based Random Access, UORA):

[0125] OFDMA refers to uplink orthogonal frequency division multiple access (OFDMA).

[0126] UORA is an OFDMA-based uplink random access mechanism defined in the 802.11ax standard. Its basic principles are as follows:

[0127] The AP allocates resource units (RU) for random access through a trigger frame. Specifically, the trigger frame includes one or more user information fields (UIF), each UIF configures an RU, and multiple UIFs are allowed to configure multiple consecutive RUs of the same size. In addition, each UIF includes an "AID12" field. When the "AID12" field is set to 0, it indicates that the RU configured by the current UIF is the RU allocated to the STA associated with the AP; when the "AID12" field is set to 2045, it indicates that the RU configured by the current UIF is the RU allocated to the unassociated STA.

[0128] Wherein, one RU includes multiple subcarriers, and different RUs include different multiple subcarriers. Further, the multiple subcarriers included in one RU are orthogonal to each other.

[0129] It should be noted that the AP does not specify which STA the RU allocated by the trigger frame is allocated to. The STA that receives the trigger frame can select the RU allocated by the trigger frame for uplink transmission through the OFDMA contention window (OCW) and OFDMA random access backoff (OBO).

[0130] Specifically, a STA supporting UORA can randomly select a value in [0, OCW] as the initial value of the OBO counter. After receiving the UORA trigger frame, the total number of RUs configured in the UORA trigger frame is subtracted from the initial value of the OBO counter. If the result is less than or equal to 0, the STA randomly selects a UR from the RUs configured in the UORA trigger frame for uplink transmission; if the result is greater than 0, it continues to back off and wait for the next UORA trigger frame.

[0131] 3. Aggregate-MAC protocol data unit (APMDU):

[0132] Here, MAC refers to media access control (MAC).

[0133] APMDU is a physical layer data frame or physical layer message formed by encapsulating a MAC service data unit (MSDU) or an aggregated MAC service data unit (AMSDU) to obtain an MDPU, and then aggregating multiple MDPUs.

[0134] For AMPDU, the sender only needs to perform channel contention or backoff once, that is, it can send multiple MPDUs at the same time, thereby reducing the channel resource consumption caused by sending each MDPU separately.

[0135] 4. Block Acknowledgement (BA):

[0136] After receiving the AMPDU, the receiving end decodes each MPDU in the AMPDU and sends feedback for each MPDU. In the BA mechanism, the feedback of multiple MPDUs included in the AMPDU is completed through one BA frame, reducing the number of feedback frames. Specifically, the BA frame can include a block confirmation bitmap to feedback the decoding status of each MPDU.

[0137] 5. Network allocation vector (NAV):

[0138] NAV is a method defined by WLAN for virtual carrier monitoring. After a WLAN device competes to obtain a channel, it usually sends one or more frames. When the NAV method is used, the WLAN device that obtains the channel can set NAV in the Duration field of the MAC frame header included in each frame it sends to notify other WLAN devices of the duration of the channel used by the WLAN device that currently obtains the channel. Other WLAN devices that hear the frame will remain silent during the duration, that is, stop competing for the channel.

[0139] For example, Figure 6 As shown in the figure, taking STAa competing for the channel and STAa and STAb performing data transmission as an example, after STAa competes for the channel, it sends a request to send (RTS) frame in a broadcast manner, and NAV1 is set in the RTS frame to indicate that STA1 sends a data frame to the designated receiving end (STAb) within the duration indicated by NAV1. After STAb receives the RTS frame and a short interframe space (SIFS) is set, it sends a clear to send (CTS) frame in a broadcast manner to confirm STAa's transmission. NAV2 is set in the CTS frame to indicate the duration of using the channel. The start time of the duration indicated by NAV2 is the end time of the CTS frame, and the end time of the duration indicated by NAV2 is the same as that of the duration indicated by NAV1. After that, STAa sends a data (Data) frame to STAb, and STAb replies an acknowledgment (ACK) frame to STAa.

[0140] It is understandable that the data frame sent by STAa and the ACK frame sent by STAb also include NAV, but Figure 6 Other STAs that receive the RTS frame or CTS frame within the duration indicated by NAV1 remain silent, and after the DIFS time when the duration indicated by NAV1 ends, other STAs start to compete for the channel.

[0141] 6. Unicast and multicast:

[0142] Unicast refers to a point-to-point transmission mode, that is, one sender corresponds to one receiver. For example, Figure 7a As shown, assuming that there are 6 WLAN devices from WLAN device 1 to WLAN device 6, the sending end may be WLAN device 1, and the receiving end may only be WLAN device 2. At this time, it can be considered that unicast transmission is performed between WLAN device 1 and WLAN device 2.

[0143] Multicast refers to a multi-point to multi-point transmission mode. Unless otherwise specified, the multicast involved in this application refers to the multicast transmission between the AP and multiple STAs, that is, the AP only needs to send one copy of the data to all STAs in the multicast group. For example, Figure 7b As shown, assuming that there is AP1, and 5 STAs from STA1 to STA5, AP1 can be used as a transmitter. When AP1 needs to send the same data to STA1, STA2, and STA5, the receivers may include STA1, STA2, and STA5, or in other words, the STAs in the multicast group may include STA1, STA2, and STA5.

[0144] In WLAN, the quality of wireless channels is unstable due to factors such as small-scale fast fading, occlusion and shadow fading, and co-channel interference. In order to ensure the reliability of transmission, the AP needs to perform rate adaptation and retransmission according to the channel quality status. In unicast transmission, the AP can obtain the link quality of the channel and the reliability of data transmission through the STA's response feedback. Based on the response feedback mechanism, on the one hand, the reliability of transmission can be guaranteed through retransmission, and on the other hand, the link rate can be adapted by adjusting the modulation and coding scheme (MCS) to ensure efficient transmission. For multicast transmission, the traditional IEEE 802.11 does not define an effective response feedback mechanism, which brings two typical problems: 1) Multicast STAs do not have any response feedback, and the reliability of multicast scenarios cannot be guaranteed through retransmission; 2) Multicast data streams are sent at a fixed minimum rate, and link quality information cannot be obtained to achieve rate adaptation, making it difficult to give full play to the potential advantages of multicast transmission efficiency.

[0145] It should be noted that the multicast STA involved in this application refers to the STA in the multicast group, or in other words, the STA that serves as the receiving end in the multicast transmission. The three descriptions can be interchangeable, and this application does not make specific limitations on this.

[0146] Regarding the reliability of multicast services, in the traditional 802.11 standard, for low-load scenarios, an effective option is for the AP to convert multicast messages into unicast messages and send them, using the ACK feedback and retransmission of the unicast transmission mode to ensure the reliability of each terminal, and the response feedback mechanism in the unicast scenario can be used to achieve rate adaptation and select the appropriate transmission rate for users with different channel qualities. However, converting multicast messages into unicast messages will result in repeated message transmission. For the same data stream, the bandwidth resources or delay required for unicast compared to multicast increases sharply as the number of STAs in the multicast group increases, making this solution difficult to apply to scenarios with high user density.

[0147] Currently, there are many multicast services in high-density user scenarios in WLAN networks, such as VR teaching, video conferencing, and electronic schoolbags. These services require a large number of STAs supported by APs and place extreme demands on indicators such as reliability, throughput, and latency. Therefore, in order to provide efficient and reliable transmission guarantees for multicast services in high-density scenarios in WLAN networks, 802.11bc takes the optimization of the sending feedback method of multicast services as one of the main discussion topics.

[0148] Currently, a groupcast retries (GCR) feedback mechanism is proposed in the 802.11aa standard, which extends the existing BA mechanism of the 802.11 standard to the group addressed transmission service (GATS) scenario, that is, extends the BA mechanism to the multicast scenario.

[0149] Specifically, under this feedback mechanism, the AP sends a multicast AMPDU to the STAs in the multicast group, and then uses a block ACK request (BAR) frame to poll some or all of the STAs in the multicast group. After the STA receives the BAR frame, it replies with a BA frame to the AP after a SIFS period of time to inform the AP of the decoding status of the multicast AMPDU.

[0150] For example, Figure 8 As shown in the figure, taking the STAs in the multicast group including STA1, STA2, and STA3 as an example, the AP first sends a multicast AMPDU, and then sends BAR1 to STA1. After receiving BAR1, STA1 replies BA1 to the AP. After receiving BA1, the AP continues to send BAR2 to STA2, and STA2 replies BA2 to the AP after receiving BAR1. Similarly, after receiving BA2, the AP continues to send BAR3 to STA3, and STA2 replies BA3 to the AP after receiving BAR3.

[0151] Depend on Figure 8 It can be seen that in this feedback mechanism, the AP requests the multicast STA to feed back BA frames one by one in a polling manner. As the number of multicast STAs increases, the number of BAR frames and BA frames exchanged between the AP and the multicast STA in this mechanism also increases. Applying this feedback mechanism to high-density user scenarios will introduce huge GCR control frame transmission overhead.

[0152] In order to reduce the transmission overhead of GCR control frames, the 802.11ax standard optimizes the GCR feedback mechanism and defines the GCR MU-BAR mechanism, where MU refers to multi-user (MU). In the GCR MU-BAR mechanism, the AAP sends a multicast AMPDU to the STAs in the multicast group, and then uses the MU-BAR frame to schedule multiple STAs in the multicast group to reply to the BA frame on the RU allocated to them.

[0153] For example, Fig. 9 As shown, taking the STAs in the multicast group including STA1, STA2, and STA3 as an example, the AP first sends a multicast AMPDU, and then sends a MU-BAR frame. In the MU-BAR frame, RUs are allocated to STA1, STA2, and STA3 respectively. After STA1, STA2, and STA3 receive the MU-BAR frame, they reply BA1, BA2, and BA3 to the AP respectively on the RU allocated to them by the AP.

[0154] Depend on Fig. 9 It can be seen that in this feedback mechanism, the AP can request multiple multicast STAs to feedback BA frames through one MU-BAR frame. Figure 8 The scheme shown can reduce the transmission overhead of the GCR control frame. However, the number of multicast STAs that request feedback from a MU-BAR frame is limited. In high-density user scenarios, if you want to ensure that the AP collects the BA frames of all multicast STAs, the AP still needs to send multiple MU-BARs, that is, multiple rounds of GCR control frame interactions are required. For example, when the channel bandwidth is 40MHz, there are 18 available RUs that can be allocated to STA feedback BA frames. Considering VR teaching, a typical high-density user scenario, assuming that there are 60 multicast STAs, in order to ensure that the AP receives the BA frames of the 60 multicast STAs, a total of 4 rounds of MU-BAR frame and BA frame interactions are required, and there is still a large transmission overhead.

[0155] Based on this, the present application provides a multicast feedback method, which can provide feedback on multicast data frames with lower transmission overhead, so that the access point obtains the channel quality status according to the feedback from the site.

[0156] The technical solution provided by the embodiments of the present application is introduced below in conjunction with the accompanying drawings.

[0157] It should be noted that the lengths of the various fields involved in this application are only exemplary. This application does not limit the lengths of various fields to the lengths given in this application. The lengths of the fields may be longer or shorter than the lengths given in this application.

[0158] It should be noted that in the following embodiments of the present application, the message names between the various devices, the names of the various parameters, or the names of the various information are only examples. In other embodiments, they may also be other names, and the method provided in the present application does not make specific limitations on this.

[0159] It is understandable that in the embodiments of the present application, the access point and / or STA may perform some or all of the steps in the embodiments of the present application, and these steps or operations are only examples. The embodiments of the present application may also perform other operations or variations of various operations. In addition, the various steps may be performed in different orders presented in the embodiments of the present application, and it is possible that not all operations in the embodiments of the present application need to be performed.

[0160] See also Fig.10 , is a schematic flow chart of the multicast feedback method provided in the embodiment of the present application. Figure 1 The application scenario shown is taken as an example. Of course, the embodiment of the present application can also be applied to other possible communication scenarios or communication systems, as long as it involves the scenario of feedback of multicast data frames, the feedback can be achieved through the method provided by the embodiment of the present application.

[0161] Specifically, Fig.10 As shown, the service transmission method provided by the present application includes the following steps:

[0162] S1001: An access point sends a multicast data frame. Correspondingly, a first station receives a multicast data frame from the access point.

[0163] The first site is any one of the multiple sites in the multicast group.

[0164] It can be understood that the multicast data frame sent by the access point can be received by multiple sites in the multicast group. The embodiment of the present application is explained by taking the example that the sites in the multicast group include the first site, and the first site receives the multicast data frame. The following embodiment also takes the first site as the main body to explain the operations implemented by the sites in the multicast group.

[0165] It should be understood that multiple sites within a multicast group have the same or similar processing actions and can all execute the functions or actions implemented by the first site provided in this application.

[0166] In some embodiments, the multicast data frame is composed of multiple data frames. For example, the multicast data frame is an AMPDU, and the data frames constituting the multicast data frame are multiple MPDUs.

[0167] As an example, when the multicast data frame is composed of multiple data frames, the data frame can also be called a sub-data frame of the multicast data frame. For example, when the multicast data frame is AMPDU, MPDU can also be called a sub-data frame of AMPDU.

[0168] In some other embodiments, the multicast data frame includes only one data frame, for example, the data frame is an MPDU, and the multicast data frame includes only one MPDU, or in other words, the multicast data frame is an MPDU.

[0169] S1002: The access point sends a multicast feedback trigger frame. Correspondingly, the first station receives the multicast feedback trigger frame from the access point.

[0170] The multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly.

[0171] For ease of description, the present application records the number of all sites in the multicast group as N, that is, the multicast group includes N sites in total; the number of multiple sites in the multicast group that schedules the multicast feedback trigger frame is recorded as M, that is, the M sites in the multicast group that schedules the multicast feedback trigger frame feedback whether the multicast data frame is decoded correctly, and the M sites include the first site. Wherein, N and M are positive integers greater than 1, and M is less than or equal to N.

[0172] In some embodiments, the value of M is positively correlated with the channel bandwidth. That is, the number of stations that feedback whether the multicast data frame is correctly decoded in a multicast group scheduled by a multicast feedback trigger frame is positively correlated with the channel bandwidth, that is, the larger the channel bandwidth, the more stations there are for multicast feedback trigger frame scheduling.

[0173] As an example, the value of M and the channel bandwidth satisfy the following formula (2):

[0174] M=C*2 BW *(MultiplexingFlag+1) (2)

[0175] Among them, C is a constant with a value of 18, which means the minimum number of sites that can be scheduled at a single time when the bandwidth is 20 MHz; BW indicates the channel bandwidth, for example, BW equals 0, indicating that the channel bandwidth is 20 MHz, BW equals 1, indicating that the channel bandwidth is 40 MHz, BW equals 2, indicating that the channel bandwidth is 80 MHz, and BW equals 3, indicating that the channel bandwidth is 80+80 MHz, or 160 MHz; the value of MultiplexingFlag is 0 or 1.

[0176] For example, taking the channel bandwidth as 40MHz, the maximum value of M is 72, that is, in this application, the access point can schedule up to 72 stations in the multicast group to feedback whether the multicast data frame is decoded correctly through a multicast feedback trigger frame. Fig. 9 The GCR MU-BAR feedback scheme described above, when the channel bandwidth is 40MHz, can use 18 RUs for feedback, that is, one MU-BAR frame can schedule up to 18 sites in the multicast group to feedback whether the multicast data frame is decoded correctly. Assuming that a multicast group includes 60 sites in total, through the scheme of this application, the access point only needs to send one multicast feedback trigger frame to schedule the 60 sites for feedback; if using Fig. 9 In the scheme shown, if all 60 stations are to be scheduled for feedback, the access point needs to send four MU-BAR frames. It can be seen that the control frame overhead can be reduced through the scheme of the present application.

[0177] In some embodiments, the multicast feedback trigger frame includes a first field, and when the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is a multicast retransmission confirmation request. Through the first field, the stations in the multicast group can determine the type of the multicast feedback trigger frame, and then can provide feedback based on the feedback trigger frame.

[0178] As an example, the multicast feedback trigger frame is a NFRP trigger frame, and the first field is a feedback type field in a user information field of the NFRP trigger frame. The structure of the user information field can be referred to Figure 4 , which will not be described in detail here. Further, the first value may be any one of 1-15. Taking the first value equal to 1 as an example, the value of the feedback type field and its corresponding feedback type are shown in Table 1 below.

[0179] Table 1

[0180]

[0181] That is to say, the present application can reuse the feedback type field of the NFRP trigger frame and use a reserved value of the feedback type field in the 802.11ax standard to represent the multicast retransmission confirmation request to indicate whether the scheduled STA feedback multicast data frame is decoded correctly.

[0182] In some embodiments, the multicast feedback trigger frame includes a second field, and the second field is used to indicate a multicast data frame. Through the second field, the multicast data frame can be clearly indicated, so that the stations in the multicast group can determine that the multicast data frame indicated by the multicast feedback trigger frame needs to be fed back, and thus the multicast data frame is fed back, thereby making the access point and the station have the same understanding of the feedback object, thereby improving the feedback accuracy.

[0183] As an example, the multicast feedback trigger frame is a NFRP trigger frame, and the second field is a field in the user information field of the NFRP trigger frame. That is, the present application extends a second field in the user information field of the NFRP trigger frame defined in the 802.11ax standard to indicate the multicast data frame that needs feedback.

[0184] Exemplarily, the structure of the user information field of the NFRP trigger frame can be as follows: Fig.11a As shown. The second field can be set to the index of the multicast data frame. For example, when the multicast data frame is an MPDU, the second field can be set to the sequence index of the MPDU; when the multicast data frame is an AMPDU, the second field can be set to the index of the AMPDU, that is, the AMPDU can be numbered, and the index of an AMPDU is used to uniquely identify the AMPDU. By setting the second field to the index of the AMPDU, the feedback AMPDU can be uniquely determined.

[0185] As an example, the second field may include a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the start data frame in the multicast data frame, and the second subfield is used to carry the sequence number index of the end data frame in the multicast data frame.

[0186] Exemplarily, the first subfield may be referred to as a Block ACK Starting Sequence field, and the second subfield may be referred to as a Block ACK Ending Sequence field. The structure of the User Information field of the NFRP trigger frame may be as follows: Fig.11b shown.

[0187] For example, Fig.11b In the structure shown, when the multicast data frame is an MPDU, the block confirmation start sequence field and the block confirmation end sequence field can both be set to the sequence number index of the MPDU; when the multicast data frame is an AMPDU, the block confirmation start sequence field can be set to the sequence number index of the start MPDU in the AMPDU, and the block confirmation end sequence field can be set to the sequence number index of the end MPDU in the AMPDU.

[0188] As another example, the second field may include a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the starting data frame in the multicast data frame, and the second subfield is used to carry the number of data frames included in the multicast data frame.

[0189] Exemplarily, when the multicast data frame is an MPDU, the first subfield can be set to the sequence number index of the MPDU, and the second subfield can be set to 1, indicating that the multicast data frame includes 1 data frame; when the multicast data frame is an AMPDU, the first subfield can be set to the sequence number index of the starting MPDU in the AMPDU, and the second subfield can be set to the number of MPDUs included in the AMPDU.

[0190] As another example, the second field may include a first subfield and a second subfield, the first subfield is used to carry the number of data frames included in the multicast data frame, and the second subfield is used to carry the sequence number index of the end data frame in the multicast data frame.

[0191] Exemplarily, when the multicast data frame is an MPDU, the first subfield can be set to 1, indicating that the multicast data frame includes 1 data frame, and the second subfield can be set to the sequence number index of the MPDU; when the multicast data frame is an AMPDU, the first subfield can be set to the number of MPDUs included in the AMPDU, and the second subfield can be set to the sequence number index of the ending MPDU in the AMPDU.

[0192] It should be noted that the "serial number index" involved in this application can also be called "serial number", and the two can be interchangeable, and this application does not make any specific limitations on this.

[0193] S1003: The first site determines whether the M sites scheduled by the multicast feedback trigger frame include the first site.

[0194] In some embodiments, the multicast feedback trigger frame may include a starting AID. After the first site receives the multicast feedback trigger frame, it is determined whether the AID of the first site is greater than or equal to the starting AID and less than the sum of the starting AID and M. If so, the first site is a site scheduled by the multicast feedback trigger frame. If not, the first site is not a site scheduled by the multicast feedback trigger frame. This application is explained by taking the first site being a site scheduled by the multicast feedback trigger frame as an example, that is, the M sites scheduled by the multicast feedback trigger frame include the first site.

[0195] In some embodiments, after the first site determines that the M sites scheduled for the multicast feedback trigger frame include the first site, if the multicast data frame is decoded correctly, execute the following step S1004a; if the multicast data frame is not decoded correctly, or the multicast data frame is decoded incorrectly, execute the following step S1004b or S1004c.

[0196] S1004a. The first station sends a multicast feedback report frame to the access point on the first subcarrier.

[0197] The first subcarrier is a subcarrier in the first subcarrier set that is associated with the first site, and the first subcarrier set is used to carry the multicast feedback report frame when correctly decoded.

[0198] In some embodiments, the first subcarrier set may be configured by the access point before step S1002. The first subcarrier set includes N subcarriers, which are respectively associated with N sites in the multicast group, that is, one site in the multicast group is associated with one subcarrier in the first subcarrier set, and different sites are associated with different subcarriers. In other words, when a site in the multicast group correctly decodes the multicast data frame, it sends a multicast feedback data frame to the access point on the subcarrier associated with it in the first subcarrier set.

[0199] S1004b. The first station sends a multicast feedback report frame to the access point on the second subcarrier.

[0200] The second subcarrier is a subcarrier in the second subcarrier set that is associated with the first site, and the second subcarrier set is used to carry the multicast feedback report frame when the decoding is not correct.

[0201] In some embodiments, the second subcarrier set may be configured by the access point before step S1002. The second subcarrier set includes N subcarriers, which are respectively associated with N sites in the multicast group, that is, one site in the multicast group is associated with one subcarrier in the second subcarrier set, and different sites are associated with different subcarriers. In other words, when a site in the multicast group fails to correctly decode the multicast data frame, it sends a multicast feedback data frame to the access point on the subcarrier associated with it in the second subcarrier set.

[0202] In some embodiments, the first subcarrier set and the second subcarrier set are configured by the access point through one broadcast frame, or may be configured through two broadcast frames, which is not specifically limited in the present application.

[0203] S1004c: The first station does not send a multicast feedback report frame to the access point on the first subcarrier and the second subcarrier.

[0204] The first subcarrier and the second subcarrier may refer to the above description, which will not be described again. That is, when the first station fails to decode the multicast data frame correctly, it may not reply the multicast feedback report frame to the access point.

[0205] In some embodiments, the multicast feedback report frame involved in the present application is an empty data frame, that is, it does not include a data field, which can also be called an empty data packet feedback report (NDP Feedback Report) frame. Exemplarily, the structure of the multicast feedback report frame can be as follows: Figure 5 shown.

[0206] It can be understood that the multicast feedback report frame can be considered as a reply frame of the multicast feedback trigger frame. In other words, the multicast feedback report frame is a frame triggered by the multicast feedback trigger frame.

[0207] After sending the multicast feedback trigger frame, the access point may perform energy detection on the subcarriers included in the first subcarrier set and the second subcarrier set.

[0208] When the first station performs step S1004a, the access point may perform the following step S1005a:

[0209] S1005a: The access point detects energy on the first subcarrier and determines that the first station correctly decodes the multicast data frame.

[0210] It can be understood that the first subcarrier set is configured by the access point. On the access point side, it is possible to determine the site associated with the subcarriers in the first subcarrier set. Therefore, when the access point detects energy on the first subcarrier, it can be determined that the first subcarrier is associated with the first site, thereby determining that the first site correctly decodes the multicast data frame.

[0211] When the first station executes step S1004b, the access point executes the following step S1005b:

[0212] S1005b: The access point detects energy on the second subcarrier and determines that the first station does not correctly decode the multicast data frame.

[0213] It can be understood that the second subcarrier set is configured by the access point. On the access point side, it is possible to determine the site associated with the subcarriers in the second subcarrier set. Therefore, when the access point detects energy on the second subcarrier, it can determine that the second subcarrier is associated with the first site, thereby determining that the first site correctly decodes the multicast data frame.

[0214] When the first station executes step S1004c, the access point executes the following step S1005c:

[0215] S1005c: The access point detects no energy on the first subcarrier and the second subcarrier, and determines that the first station does not correctly decode the multicast data frame.

[0216] Through the above scheme, the access point can determine the sites that correctly decode the multicast data frame and the sites that do not correctly decode the multicast data frame among the M sites scheduled for the multicast feedback trigger frame. When M is less than N, the above scheme can be repeatedly executed starting from step S1002 to schedule the other sites in the N sites in the multicast group except the M sites scheduled this time to provide feedback. When M is equal to N, the access point can determine the sites that correctly decode the multicast data frame and the sites that do not correctly decode the multicast data frame among the N sites in the multicast group.

[0217] Based on the above scheme, when the multicast data frame is an MPDU, the access point schedules the stations in the multicast group to reply to the multicast feedback report frame, and learns whether the stations in the multicast group correctly decode the MPDU by detecting energy on the subcarrier associated with the station. Afterwards, the access point can retransmit the MPDU for the station that has not been correctly decoded to improve transmission reliability, or adjust the link rate to improve transmission efficiency.

[0218] In some embodiments, when the multicast data frame is an AMPDU, the access point can obtain the sites that do not correctly decode the AMPDU among the N sites in the multicast group through the above scheme. Further, in order to obtain the MPDU that is not correctly decoded in the AMPDU, Fig.12 As shown, the method provided by the present application also includes the following steps S1006-S1007:

[0219] S1006: The access point sends a block ACK request (BAR) trigger frame. Correspondingly, the first station receives the block ACK request trigger frame from the access point.

[0220] The block confirmation request trigger frame is used to schedule at least one second station to feed back the sequence index of the MPDU with decoding error in the AMPDU on the respective associated RUs. The second station is a station that does not correctly decode the AMPDU among the N stations in the multicast group.

[0221] For ease of description, the present application records the number of sites that do not correctly decode AMPDU in the multicast group as P, that is, the multicast group includes a total of P sites that do not correctly decode AMPDU; the number of at least one second site that triggers the block confirmation request frame scheduling is recorded as K, that is, the sequence index of the MPDU that is incorrectly decoded is fed back by the K sites that do not correctly decode AMPDU in the multicast group that triggers the block confirmation request frame scheduling. Wherein, P and K are positive integers, and K is less than or equal to P.

[0222] It should be noted that, in this application, the first site is used as an example to trigger a block confirmation request frame for scheduling one of at least one second site. That is to say, in this scenario, the first site also serves as the second site. In addition, for the first site, the block confirmation request trigger frame is used to schedule the first site to feedback the sequence index of the MPDU with decoding errors in the AMPDU on the RU associated with the first site.

[0223] In some embodiments, the block confirmation request trigger frame includes the AID of each second site among the K second sites and the RU associated with each second site, or in other words, the RU allocated to each second site.

[0224] As an example, the confirmation request trigger frame may be a MU-BAR trigger frame in the 802.11ax standard, or a trigger frame obtained by extending or deleting the MU-BAR trigger frame in the 802.11ax standard.

[0225] It is understandable that the block confirmation request trigger frame sent by the access point can be received by the K second sites, and the embodiment of the present application is described by taking the first site among the K second sites as an example. It should be understood that multiple second sites among the K second sites have the same or similar processing actions, and can all execute the functions or actions implemented by the first site provided in the following embodiments of the present application.

[0226] S1007: The first station sends a block acknowledgement (BA) frame to the access point on the RU associated with the first station. Correspondingly, the access point receives the block acknowledgement frame from the first station on the RU associated with the first station.

[0227] The RU associated with the first site is the RU allocated to the first site in the block confirmation request trigger frame.

[0228] The block acknowledgment frame is used to indicate an MPDU in the AMPDU that is decoded incorrectly by the first station. As an example, the block acknowledgment frame may include a block acknowledgment bitmap (Block ACK Bitmap), that is, a bitmap is used to indicate an MPDU in the AMPDU that is decoded incorrectly. Specifically, each bit in the block acknowledgment bitmap corresponds to an MPDU in the AMPDU. When a certain bit is 1, it indicates that the MPDU corresponding to the bit is decoded incorrectly, and when the bit is 0, it indicates that the MPDU corresponding to the bit is decoded correctly; or, when a certain bit is 0, it indicates that the MPDU corresponding to the bit is decoded incorrectly, and when the bit is 1, it indicates that the MPDU corresponding to the bit is decoded correctly.

[0229] For example, if the AMPDU includes 5 MPDUs, the sequence indexes are 10-14 respectively, and the first station decodes the MPDUs with sequence indexes 10, 13, and 14 incorrectly, if a bit of 1 indicates that the corresponding MPDU decoding is incorrect, then the block confirmation bitmap may be: 10011. Among them, from left to right, the first 1 indicates that the MPDU with sequence index 10 is decoded incorrectly, the second and third 0s indicate that the MPDUs with sequence indexes 11 and 12 are decoded correctly, respectively, and the last two 1s indicate that the MPDUs with sequence indexes 13 and 14 are decoded incorrectly, respectively.

[0230] Through the above steps S1006 and S1007, the access point can determine the MDPU that each station decodes incorrectly among the K stations that do not correctly decode the AMPDU. When K is less than P, the above steps S1006 and S1007 can be repeatedly executed to schedule the other stations among the P stations that do not correctly decode the AMPDU except the K stations scheduled this time to feedback the sequence number index of the MPDU that has been decoded incorrectly. When P is equal to K, the access point can determine the MDPU that each station decodes incorrectly among all the stations that do not correctly decode the AMPDU.

[0231] Based on the above scheme, when the multicast data frame is AMPDU, the present application provides a two-level feedback mechanism. In the first level of feedback, the access point can first trigger the frame scheduling through multicast feedback to reply to the multicast feedback report frame by the station in the multicast group, so as to learn the station in the multicast group that did not correctly decode the AMPDU. In the second level of feedback, the access point triggers the frame scheduling through a block confirmation request to feedback the sequence number index of the MPDU with incorrect decoding. Therefore, the access point can retransmit the MPDU with incorrect decoding to improve the transmission reliability, or it can also adjust the link rate to improve the transmission efficiency.

[0232] For example, see Fig.13 , taking the multicast group including STA1, STA2, and STA3 as an example, in the above two-level feedback mechanism, the AP first sends the multicast data frame AMPDU, and then sends the multicast feedback trigger frame. Assuming that STA1 decodes the AMPDU correctly, and STA2 and STA3 do not decode the AMPDU correctly, after receiving the multicast feedback trigger frame, STA2 and STA3 respectively send multicast feedback report frames to the AP on the subcarriers associated with them in the second subcarrier set. After receiving the multicast feedback trigger frame, STA1 sends a multicast feedback report frame to the AP on the subcarriers associated with it in the first subcarrier set.

[0233] Accordingly, based on the subcarriers where energy is detected, the access point can determine that STA2 and STA3 did not decode the AMPDU correctly, and thus send a block confirmation trigger frame, scheduling STA2 and STA3 to feedback the index of the MPDU with decoding errors in the AMPDU on their associated RUs. After receiving the block confirmation trigger frame, STA2 and STA3 send block confirmation frames on their associated RUs to indicate the MPDU with decoding errors.

[0234] See also Fig.14 ,for Fig.13 The timing diagram of the communication process shown in FIG. 4 is taken as an example that the multicast feedback trigger frame is an NFRP frame, the multicast feedback report frame is an NDP frame, and the block confirmation request trigger frame is an MU-BAR frame.

[0235] Based on the solution of the present application, when the multicast data frame is AMPDU, the access point filters out the STA with correct decoding through the first-level feedback, so that the allocation of RU to the STA with correct decoding can be avoided in the second-level feedback, thereby effectively reducing the overhead of the interaction between the BAR trigger frame and the BA frame in the second-level feedback.

[0236] Taking the channel bandwidth of 40MHz as an example, assuming that there are 60 STAs in the multicast group, the number of RUs that can be used to feedback the MPDU with decoding errors is 18. Based on the GCR MU-BAR feedback mechanism in the 802.11ax standard, the AP needs to send 4 MU-BAR trigger frames. Correspondingly, the STAs in the multicast group need to reply with BA frames regardless of whether they decode the AMPDU correctly. Based on the solution of this application, within a certain packet error ratio (PER) range, the AP only needs to send two block confirmation trigger frames, and the STA that decodes the AMPDU correctly does not need to reply with BA frames.

[0237] The above is an introduction to the multicast feedback process provided by this application. In addition, this application takes into account the scenario where there are non-multicast sites within the coverage of the access point. In this scenario, the data transmission initiated by the non-multicast site on the channel may interfere with the frames involved in the above process. Based on this, this application uses the NAV mechanism to protect the channel, thereby improving the reliability of the above feedback process.

[0238] In some embodiments, the multicast feedback trigger frame sent by the access point may include a third field, and the third field is used to indicate the first NAV. Exemplarily, the third field may be a duration field in the header of the multicast feedback trigger frame.

[0239] As an example, when the multicast data frame is an MPDU, the duration of the first NAV is the sum of the duration of the multicast feedback report frame and SIFS, and the multicast feedback report frame is a reply frame of the multicast feedback trigger frame. Fig.15 As shown, taking the multicast data frame as MPDU, the STAs in the multicast group include STA1 and STA2, and the non-multicast station STA3 within the coverage of the AP as an example, after the AP sends the MPDU, it sends a multicast feedback trigger frame, which indicates the first NAV, and STA1 and STA2 send multicast feedback report frames in the first NAV according to the scheduling of the AP ( Fig.15 STA3 remains silent within the first NAV.

[0240] As another example, when the multicast data frame is an AMPDU, the duration of the first NAV is the sum of the following items: the duration of the multicast feedback report frame, the duration of the block confirmation request trigger frame, the duration of the block confirmation frame, and SIFS.

[0241] Exemplarily, in the above process, if a block confirmation request trigger frame can schedule all stations in the multicast group that have not correctly decoded the AMPDU to reply with a block confirmation frame, the duration of the first NAV is:

[0242] The duration of a multicast feedback report frame + the duration of a block confirmation request trigger frame + the duration of a block confirmation frame + 3 SIFS;

[0243] If multiple block ACK request frames are required to schedule all stations in the multicast group that have not correctly decoded the AMPDU to reply with block ACK frames, the duration of the first NAV is:

[0244] The duration of a multicast feedback report frame + the duration of L block confirmation request trigger frames + the duration of L block confirmation frames + (2L+1) SIFS.

[0245] Wherein, L is the number of block confirmation request trigger frames sent by the access point.

[0246] For example, Fig.16 As shown, taking the multicast data frame as AMPDU, the STAs in the multicast group include STA1 and STA2, and the non-multicast site STA3 within the coverage of the AP as an example, after the AP sends the AMPDU, it sends a multicast feedback trigger frame, which indicates the first NAV, and STA1 and STA2 send multicast feedback report frames in the first NAV according to the scheduling of the AP ( Fig.16 If STA2 does not decode the MPDU correctly, the AP sends a block confirmation request trigger frame to schedule STA2 to feedback a block confirmation frame. After STA2 receives the block confirmation request trigger frame, it sends a block confirmation frame according to the AP's schedule to indicate the MPDU with decoding errors. STA3 remains silent within the first NAV.

[0247] Based on this solution, the access point can protect the channel in the feedback process by indicating the first NAV in the multicast feedback trigger frame, reduce the interference of non-multicast sites on the feedback process, improve feedback efficiency, and reduce feedback delay, so that the access point can retransmit erroneous MPDUs in time, reduce multicast service delays, or adjust the transmission rate in time to improve the multicast service transmission rate.

[0248] In addition to the multicast feedback method introduced above, the present application also provides a multicast feedback method, which selects a suitable MCS at the access point, controls the PER of a single transmission within a certain range, and ensures that only a few multicast STAs have decoding errors. By means of uplink OFDMA random access, that is, the idea of ​​UORA, at least one RU is pre-allocated for multicast STAs that have not correctly decoded multicast data frames to feedback decoding error information.

[0249] For details, see Fig.17 , the multicast feedback method comprises the following steps:

[0250] S1701: An access point sends a multicast data frame. Correspondingly, a first station receives a multicast data frame from the access point.

[0251] The first site is any one of the multiple sites in the multicast group.

[0252] In some embodiments, the multicast data frame is composed of multiple data frames. For example, the multicast data frame is an AMPDU, and the data frames constituting the multicast data frame are multiple MPDUs.

[0253] In some other embodiments, the multicast data frame includes only one data frame, for example, the data frame is an MPDU, and the multicast data frame includes only one MPDU, or in other words, the multicast data frame is an MPDU.

[0254] The specific details of step S1701 can be found in the related description of the above step S1001, which will not be repeated here.

[0255] S1702: The access point sends a multicast feedback trigger frame. Correspondingly, the first station receives the multicast feedback trigger frame from the access point.

[0256] The multicast feedback trigger frame is used to configure at least one RU, which is used for sites in the multicast group to transmit block confirmation frames of multicast data frames during the UORA process, and the block confirmation frames of multicast data frames are used to indicate data frames with decoding errors in multicast data frames.

[0257] In some embodiments, Fig.17 The "multicast feedback trigger frame" involved in the method shown may also be referred to as an "uplink OFDMA random access-negative acknowledgment poll trigger (UORA-NACK Poll Trigger) frame", and the two may be interchangeable, and this application does not make any specific limitation on this.

[0258] In some embodiments, the multicast feedback trigger frame may include at least one user information field (UIF), each of which is used to configure an RU, allowing multiple UIFs to configure multiple consecutive RUs of the same size. In addition, each UIF includes an "AID12" field, and the "AID12" field is set to 0, indicating that the RU configured by the current UIF is the RU allocated to the STA associated with the AP.

[0259] For example, a multicast feedback trigger frame includes three UIFs, and the three UIFs are respectively configured with RU1, RU2, and RU3. The setting of the "AID12" field in the UIF and the distribution diagram of the RUs can be as follows: Fig.18 shown.

[0260] In some embodiments, the multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the current multicast feedback trigger frame is uplink orthogonal frequency division multiple access random access-negative acknowledgment polling, ie, UORA-NACK Poll.

[0261] In some embodiments, the multicast feedback trigger frame may be a newly defined MU-BAR trigger frame, including a BAR control field, and the first field may be a BAR type field in the BAR control field.

[0262] For example, the format of the BAR control field can be as follows: Fig.19 As shown, it includes a 1-bit BAR confirmation policy (BARACK Policy) field, a 4-bit BAR type (BAR Type) field, a 7-bit reserved (Reserved) field, and a 4-bit service identification information (TID_INFO) field, where TID refers to the service identifier (traffic identifier, TID).

[0263] Among them, the BAR ACK Policy field is used to indicate whether the sender needs the receiver to provide immediate acknowledgment. A value of 1 indicates that it is required, and a value of 0 indicates that it is not required. The function of the service identification information (TID_INFO) field is related to the BAR frame type. For a specific description, please refer to the relevant introduction in the 802.11ax standard, which will not be repeated here. The BAR type field indicates the type of the current MU-BAR trigger frame. Furthermore, the first value can be any one of 0, 4, 5, or 7-9. Taking the first value equal to 0 as an example, the values ​​of the BAR type field and its corresponding feedback type are shown in Table 2 below.

[0264] Table 2

[0265]

[0266] That is to say, the present application can reuse the BAR type field of the MMU-BAR trigger frame, and use a reserved value of the BAR type field in the 802.11ax standard to represent uplink OFDMA random access-negative response polling.

[0267] In some embodiments, the multicast feedback trigger frame may be a newly defined basic trigger (BasicTrigger) frame, and the present application does not specifically limit the form of the multicast feedback trigger frame.

[0268] After receiving the multicast feedback trigger frame, if the first station fails to decode the multicast data frame correctly, the following step S1703 is executed.

[0269] It should be understood that the sites in the multicast group that do not correctly decode the multicast data frame have the same or similar processing actions and can all execute the functions or actions implemented by the first site provided in the following embodiments of the present application.

[0270] S1703: The first station sends a block acknowledgment frame BA of a multicast data frame to the access point through the first RU in the UORA process. Correspondingly, the access point receives the BA from the first station through the first RU in the UORA process.

[0271] The first RU is one of at least one RU configured in the multicast feedback trigger frame. The block confirmation frame is used to indicate a data frame in the multicast data frame that is decoded incorrectly by the first station.

[0272] As an example, the block acknowledgment frame may include a block acknowledgment bitmap (Block ACK Bitmap), that is, a bitmap is used to indicate a data frame with a decoding error in a multicast data frame. For details, please refer to the relevant description in the above step S1007, which will not be repeated here.

[0273] In some embodiments, the first site sends a block confirmation frame of a multicast data frame to an access point through a first RU during a UORA process, which may include: the first site selects a random number in a contention window, and when the random number is less than or equal to the total number of at least one RU configured for a multicast feedback trigger frame, selects a first RU from at least one RU, and then the first site sends a block confirmation frame of the multicast data frame to the access point on the first RU.

[0274] Based on this solution, on the one hand, the access point pre-configures at least one RU for decoding the wrong multicast STA feedback block confirmation frame, so as to obtain the transmission status of the multicast data frame, so as to retransmit the data frame with decoding error in the multicast data frame, improve the transmission reliability, or adjust the link transmission rate to improve the transmission efficiency. On the other hand, in this application, only the multicast STA with decoding error feedback block confirmation frame, and the multicast STA with correct decoding may not feedback, so compared with the traditional GCR MU-BAR feedback method defined in the 802.11ax standard, the multicast STA with correct decoding will also feedback the block confirmation frame, which can reduce the transmission overhead of the control frame.

[0275] In some embodiments, there may be multiple stations in the multicast group that do not correctly decode the multicast data frame, and these multiple stations may select the same RU to send a block confirmation frame, which will cause feedback conflicts and make the access point unable to correctly collect feedback information. In this scenario, when the access point cannot correctly decode the block confirmation frame fed back by the multicast STA, it can send a NACK frame to notify the STA in the multicast group that did not correctly decode the multicast data frame to retransmit the block confirmation frame.

[0276] For example, Fig. 20 As shown in the figure, taking the STAs in the multicast group including STA1, STA2, and STA3, STA2 correctly decodes the multicast data frame, and STA1 and STA3 do not correctly decode the multicast data frame as an example, after the AP sends the AMPDU, it sends the multicast feedback trigger frame. After STA1 and STA3 receive the multicast feedback trigger frame, they select an RU from the RUs configured in the multicast feedback trigger frame to send a block confirmation frame. Assuming that the RU selected by STA1 and STA3 is the same, the access point cannot correctly decode the block confirmation frame fed back by STA1 and STA3, then the access point sends a NACK frame. After STA1 and STA3 receive the NACK frame, they reselect the RU and retransmit the block confirmation frame on the reselected RU.

[0277] Based on this scheme, when block confirmation frames sent by multiple multicast sites conflict, the access point can instruct the multiple multicast sites to retransmit the block confirmation frames, thereby ensuring that the access point correctly decodes the block confirmation frames, obtains the transmission status of the multicast data frames, and then retransmits or adjusts the rate according to the transmission status.

[0278] In the various embodiments of the present application, unless otherwise specified or provided for in any logical conflict, the terms and / or descriptions between the different embodiments are consistent and may be referenced to each other, and the technical features in the different embodiments may be combined to form new embodiments according to their inherent logical relationships.

[0279] It can be understood that, in each of the above embodiments, the methods and / or steps implemented by the access point can also be implemented by components (such as chips or circuits) that can be used for the access point; the methods and / or steps implemented by the site can also be implemented by components (such as chips or circuits) that can be used for the site.

[0280] The above mainly introduces the solution provided by the present application from the perspective of interaction between various devices. Correspondingly, the present application also provides a communication device, which is used to implement the above various methods. The communication device can be an access point in the above method embodiment, or a device including the above access point, or a component that can be used for the access point; or, the communication device can be the first station in the above method embodiment, or a device including the above first station, or a component that can be used for the first station.

[0281] It is understandable that, in order to realize the above functions, the communication device includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0282] The embodiment of the present application can divide the functional modules of the communication device according to the above method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0283] In one implementation scenario, taking the communication device as an access point in the above method embodiment as an example, Fig.21 The schematic diagram of the structure of an access point 210 is shown. The access point 210 includes a processing module 2101 and a transceiver module 2102 .

[0284] In some embodiments, the access point 210 may also include a storage module ( Fig.21 ), for storing program instructions and data.

[0285] In some embodiments, the transceiver module 2102, which may also be referred to as a transceiver unit, is used to implement the sending and / or receiving functions. The transceiver module 2102 may be composed of a transceiver circuit, a transceiver, a transceiver or a communication interface.

[0286] In some embodiments, the transceiver module 2102 may include a receiving module and a sending module, which are respectively used to execute the receiving and sending steps performed by the access point in the above method embodiments, and / or used to support other processes of the technology described in this document; the processing module 2101 may be used to execute the processing steps (such as determining, obtaining, etc.) performed by the access point in the above method embodiments, and / or used to support other processes of the technology described in this document.

[0287] In one implementation scenario:

[0288] The transceiver module 2102 is used to send a multicast data frame; the transceiver module 2102 is also used to send a multicast feedback trigger frame, which is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly; the processing module 2101 is used to determine that the first site has not correctly decoded the multicast data frame when no energy is detected on the first subcarrier and the second subcarrier; or, the processing module 2101 is used to determine that the first site has not correctly decoded the multicast data frame when energy is detected on the second subcarrier. The first subcarrier is a subcarrier associated with the first site in the first subcarrier set, the second subcarrier is a subcarrier associated with the first site in the second subcarrier set, and the first site is any one of the multiple sites.

[0289] As a possible implementation method, the transceiver module 2102 is also used to send a block confirmation request trigger frame, which is used to schedule at least one second site to feedback the sequence index of the media access control protocol data unit MPDU with decoding errors in the AMPDU on their respective associated resource units RU, and the second site is a site among multiple sites that has not correctly decoded the AMPDU; the transceiver module 2102 is also used to receive a block confirmation frame from at least one second site on their respective associated RUs, and the block confirmation frame is used to indicate the MPDU with decoding errors in the AMPDU.

[0290] As a possible implementation method, the multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, and the duration of the first NAV is the sum of the following multiple items: the duration of the multicast feedback report frame, the duration of the block confirmation request trigger frame, the duration of the block confirmation frame, and the short frame interval SIFS, wherein the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

[0291] As a possible implementation method, the multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, and the duration of the first NAV is the sum of the duration of the multicast feedback report frame and the short frame interval SIFS, wherein the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

[0292] As a possible implementation manner, the multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is a multicast retransmission confirmation request.

[0293] As a possible implementation manner, the multicast feedback trigger frame includes a second field, and the second field is used to indicate a multicast data frame.

[0294] As a possible implementation, the second field includes a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the starting data frame in the multicast data frame, and the second subfield is used to carry the sequence number index of the ending data frame in the multicast data frame.

[0295] In another implementation scenario:

[0296] The processing module 2101 is used to generate a multicast data frame and a multicast feedback trigger frame; the transceiver module 2102 is used to send the multicast data frame and the multicast feedback trigger frame, the multicast feedback trigger frame is used to configure at least one resource unit RU, and the RU is used for the sites in the multicast group to transmit the block confirmation frame of the multicast data frame during the uplink orthogonal frequency division multiple access random access UORA process; the transceiver module 2102 is also used to receive the block confirmation frame from the first site during the UORA process through the first RU, the block confirmation frame is used to indicate the data frame with decoding error in the multicast data frame, and the first RU is one of the at least one RU configured for the multicast feedback trigger frame.

[0297] As a possible implementation manner, the multicast data frame is an aggregated media access control protocol data unit AMPDU, and the data frame is a media access control protocol data unit MPDU.

[0298] As a possible implementation manner, the multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is uplink orthogonal frequency division multiple access random access-negative acknowledgement polling.

[0299] Among them, all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

[0300] In the present application, the access point 210 is presented in the form of dividing various functional modules in an integrated manner. The "module" here may refer to a specific application-specific integrated circuit (ASIC), a circuit, a processor and a memory that executes one or more software or firmware programs, an integrated logic circuit, and / or other devices that can provide the above functions.

[0301] In some embodiments, in terms of hardware implementation, those skilled in the art may understand that the access point 210 may adopt Figure 3 The form of the WLAN device 300 is shown.

[0302] As an example, Fig.21 The function / implementation process of the processing module 2101 in can be Figure 3The processor 301 in the WLAN device 300 shown calls the computer execution instructions stored in the memory 304 to implement, Fig.21 The function / implementation process of the transceiver module 2102 can be achieved by Figure 3 The WLAN device 300 shown is implemented by the transceiver 302 .

[0303] In some embodiments, when Fig.21 When the access point 210 is a chip or a chip system, the function / implementation process of the processing module 2101 can be implemented through the input and output interface (or communication interface) of the chip or the chip system, and the function / implementation process of the transceiver module 2102 can be implemented through the processor (or processing circuit) of the chip or the chip system.

[0304] Since the access point 210 provided in this embodiment can execute the above multicast feedback method, the technical effects that can be obtained can refer to the above method embodiments, which will not be described in detail here.

[0305] In one implementation scenario, taking the communication device as the first station in the above method embodiment as an example, Fig. 22 A schematic diagram of the structure of a first site 220 is shown. The first site 220 includes a processing module 2201 and a transceiver module 2202 .

[0306] In some embodiments, the first site 220 may further include a storage module ( Fig. 22 ), for storing program instructions and data.

[0307] In some embodiments, the transceiver module 2202, which may also be referred to as a transceiver unit, is used to implement the sending and / or receiving functions. The transceiver module 2202 may be composed of a transceiver circuit, a transceiver, a transceiver or a communication interface.

[0308] In some embodiments, the transceiver module 2202 may include a receiving module and a sending module, which are respectively used to execute the receiving and sending steps performed by the first site in the above-mentioned method embodiment, and / or used to support other processes of the technology described in this document; the processing module 2201 may be used to execute the processing steps (such as determination, acquisition, etc.) performed by the first site in the above-mentioned method embodiment, and / or used to support other processes of the technology described in this document.

[0309] In one implementation scenario:

[0310] The transceiver module 2202 is used to receive multicast data frames from the access point; the transceiver module 2202 is also used to receive multicast feedback trigger frames from the access point, and the multicast feedback trigger frames are used to schedule multiple sites in the multicast group to feedback whether the multicast data frames are decoded correctly; the transceiver module 2202 is also used to send a multicast feedback report frame to the access point on a second subcarrier when the processing module 2201 determines that the multiple sites include the first site and the first site does not correctly decode the multicast data frame. The second subcarrier is a subcarrier in the second subcarrier set associated with the first site.

[0311] As a possible implementation method, the transceiver module 2202 is also used to receive a block confirmation request trigger frame from the access point, and the block confirmation request trigger frame is used to schedule the first station to feedback the sequence number index of the media access control protocol data unit MPDU with decoding errors in the AMPDU on the resource unit RU associated with the first station; the transceiver module 2202 is also used to send a block confirmation frame to the access point on the RU associated with the first station, and the block confirmation frame is used to indicate the MPDU with decoding errors in the AMPDU.

[0312] As a possible implementation method, the multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, and the duration of the first NAV is the sum of the following multiple items: the duration of the multicast feedback report frame, the duration of the block confirmation request trigger frame, the duration of the block confirmation frame, and the short frame interval SIFS, wherein the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

[0313] As a possible implementation method, the multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, and the duration of the first NAV is the sum of the duration of the multicast feedback report frame and the short frame interval SIFS, wherein the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

[0314] As a possible implementation manner, the multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is a multicast retransmission confirmation request.

[0315] As a possible implementation manner, the multicast feedback trigger frame includes a second field, and the second field is used to indicate a multicast data frame.

[0316] As a possible implementation, the second field includes a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the starting data frame in the multicast data frame, and the second subfield is used to carry the sequence number index of the ending data frame in the multicast data frame.

[0317] In another implementation scenario:

[0318] The transceiver module 2202 is used to receive multicast data frames from the access point; the transceiver module 2202 is also used to receive multicast feedback trigger frames from the access point, the multicast feedback trigger frame is used to configure at least one resource unit RU, the RU is used for the sites in the multicast group to perform uplink orthogonal frequency division multiple access random access UORA, and the UORA is used to transmit block confirmation frames of multicast data frames; the transceiver module 2202 is used to send block confirmation frames of multicast data frames to the access point through the first RU during the UORA process when the processing module 2201 fails to correctly decode the multicast data frame, the block confirmation frame is used to indicate a data frame with decoding errors in the multicast data frame, and the first RU is one of the at least one RU configured for the multicast feedback trigger frame.

[0319] As a possible implementation method, the processing module 2201 is used to select a random number in the contention window, and when the random number is less than or equal to the total number of at least one RU configured for the multicast feedback trigger frame, select a first RU from the at least one RU; the transceiver module 2202 is used to send a block confirmation frame of the multicast data frame to the access point on the first RU.

[0320] As a possible implementation manner, the multicast data frame is an aggregated media access control protocol data unit AMPDU, and the data frame is a media access control protocol data unit MPDU.

[0321] As a possible implementation manner, the multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is uplink orthogonal frequency division multiple access random access-negative acknowledgement polling.

[0322] Among them, all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

[0323] In the present application, the first site 220 is presented in the form of dividing various functional modules in an integrated manner. Here, "module" may refer to a specific application-specific integrated circuit (ASIC), a circuit, a processor and a memory that executes one or more software or firmware programs, an integrated logic circuit, and / or other devices that can provide the above functions.

[0324] In some embodiments, in terms of hardware implementation, those skilled in the art may imagine that the first station 220 may use Figure 3 The form of the WLAN device 300 is shown.

[0325] As an example, Fig. 22 The function / implementation process of the processing module 2201 in can be Figure 3The processor 301 in the WLAN device 300 shown calls the computer execution instructions stored in the memory 304 to implement, Fig. 22 The function / implementation process of the transceiver module 2202 can be Figure 3 The WLAN device 300 shown is implemented by the transceiver 302 .

[0326] In some embodiments, when Fig. 22 When the first site 220 is a chip or a chip system, the function / implementation process of the processing module 2201 can be implemented through the input and output interface (or communication interface) of the chip or the chip system, and the function / implementation process of the transceiver module 2202 can be implemented through the processor (or processing circuit) of the chip or the chip system.

[0327] Since the first site 220 provided in this embodiment can execute the above multicast feedback method, the technical effects that can be obtained can refer to the above method embodiment, which will not be repeated here.

[0328] As a possible product form, the access point and the first station described in the embodiment of the present application can also be implemented using the following: one or more field programmable gate arrays (FPGA), programmable logic devices (PLD), controllers, state machines, gate logic, discrete hardware components, any other suitable circuits, or any combination of circuits capable of performing the various functions described throughout the present application.

[0329] In some embodiments, an embodiment of the present application further provides a communication device, which includes a processor for implementing a method in any of the above method embodiments.

[0330] As a possible implementation, the communication device further includes a memory. The memory is used to store necessary program instructions and data, and the processor can call the program code stored in the memory to instruct the communication device to execute the method in any of the above method embodiments. Of course, the memory may not be in the communication device.

[0331] As another possible implementation, the communication device also includes an interface circuit, which is a code / data read / write interface circuit, which is used to receive computer execution instructions (computer execution instructions are stored in a memory, may be read directly from the memory, or may pass through other devices) and transmit them to the processor.

[0332] As another possible implementation manner, the communication device further includes a communication interface, and the communication interface is used to communicate with a module outside the communication device.

[0333] It can be understood that the communication device can be a chip or a chip system. When the communication device is a chip system, it can be composed of chips, or it can include chips and other discrete devices. The embodiments of the present application do not specifically limit this.

[0334] In some embodiments, an embodiment of the present application also provides a communication device (for example, the communication device can be a chip or a chip system), which includes an interface circuit and a logic circuit, wherein the interface circuit is used to obtain input information and / or output output information; the logic circuit is used to execute the method in any of the above method embodiments, and process and / or generate output information based on the input information.

[0335] When the communication device is used to implement the function of the access point in the above method embodiment:

[0336] In some possible designs, the output information may be a multicast data frame and a multicast feedback trigger frame, where the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly.

[0337] In some possible designs, the input information may be: a block confirmation frame of at least one second site, the block confirmation frame being used to indicate an MPDU with a decoding error in the AMPDU. Accordingly, processing according to the input information may be: determining a retransmitted MPDU or a modulated transmission rate according to the block confirmation frame.

[0338] Alternatively, when the communication device is used to implement the function of the access point in the above method embodiment:

[0339] In some possible designs, the output information may be: multicast data frames and multicast feedback trigger frames, wherein the multicast feedback trigger frames are used to configure at least one resource unit RU, and the RU is used for sites within the multicast group to transmit block confirmation frames of multicast data frames during the uplink orthogonal frequency division multiple access random access UORA process.

[0340] In some possible designs, the input information may be a block confirmation frame, which is used to indicate a data frame with decoding errors in a multicast data frame. Accordingly, processing according to the input information may be: determining a retransmitted data frame or a modulation transmission rate according to the block confirmation frame.

[0341] When the communication device is used to implement the function of the first station in the above method embodiment:

[0342] In some possible designs, the input information may be: a multicast data frame and a multicast feedback trigger frame, and the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly. Accordingly, processing according to the input information may be: when the multiple sites in the multicast group scheduled by the multicast feedback trigger frame include the first site, and the first site fails to correctly decode the multicast data frame, a multicast feedback report frame is sent to the access point on the second subcarrier, and the second subcarrier is a subcarrier in the second subcarrier set associated with the first site.

[0343] In some possible designs, the output information may be: a block confirmation frame, which is used to indicate an MPDU with a decoding error in the AMPDU.

[0344] Alternatively, when the communication device is used to implement the function of the first station in the above method embodiment:

[0345] In some possible designs, the input information may be: a multicast data frame and a multicast feedback trigger frame, the multicast feedback trigger frame is used to configure at least one resource unit RU, the RU is used for sites in the multicast group to transmit block confirmation frames of multicast data frames during uplink orthogonal frequency division multiple access random access UORA process. Accordingly, processing is performed according to the input information, which may be: when the first site fails to correctly decode the multicast data frame, a block confirmation frame of the multicast data frame is sent to the access point through the first RU during the UORA process, the block confirmation frame is used to indicate a data frame with a decoding error in the multicast data frame, and the first RU is one of the at least one RU configured for the multicast feedback trigger frame.

[0346] In some possible designs, the output information may be: a block confirmation frame, which is used to indicate a data frame with a decoding error in a multicast data frame.

[0347] Among them, the communication device provided in this embodiment can execute the method in the above method embodiment, so the technical effects that can be obtained can refer to the above method embodiment, which will not be repeated here.

[0348] As a possible product form, the access point and the first station described in the embodiment of the present application can be implemented by a general bus architecture.

[0349] For illustration purposes, see Fig.23 , Fig.23 1 is a schematic diagram of the structure of a communication device 1000 provided in an embodiment of the present application, wherein the communication device 1000 includes a processor 1001 and a transceiver 1002. The communication device 1000 may be an access point or a first station, or a chip therein. Fig.23Only the main components of the communication device 1000 are shown. In addition to the processor 1001 and the transceiver 1002, the communication device may further include a memory 1003 and an input and output device (not shown in the figure).

[0350] Among them, the processor 1001 is mainly used to process the communication protocol and communication data, and to control the entire communication device, execute the software program, and process the data of the software program. The memory 1003 is mainly used to store the software program and data. The transceiver 1002 may include a radio frequency circuit and an antenna. The radio frequency circuit is mainly used for converting baseband signals and radio frequency signals and processing radio frequency signals. The antenna is mainly used to send and receive radio frequency signals in the form of electromagnetic waves. The input and output devices, such as a touch screen, a display screen, a keyboard, etc., are mainly used to receive data input by the user and output data to the user.

[0351] The processor 1001 , the transceiver 1002 , and the memory 1003 may be connected via a communication bus.

[0352] When the communication device is turned on, the processor 1001 can read the software program in the memory 1003, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 1001 performs baseband processing on the data to be sent, and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then sends the radio frequency signal outward in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 1001. The processor 1001 converts the baseband signal into data and processes the data.

[0353] In another implementation, the RF circuit and antenna may be arranged independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be arranged remotely from the communication device.

[0354] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0355] The steps in the method of the embodiment of the present application can be adjusted in order, combined and deleted according to actual needs.

[0356] The modules in the device of the embodiment of the present application can be merged, divided and deleted according to actual needs.

[0357] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or may contain one or more servers, data centers and other data storage devices that can be integrated with the medium. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a solid state disk (SSD)), etc. In the embodiment of the present application, the computer may include the aforementioned device.

[0358] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in a claim. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0359] Although the present application has been described in conjunction with specific features and embodiments thereof, it is obvious that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely exemplary illustrations of the present application as defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A multicast feedback method, characterized in that: The method comprises: The access point sends a multicast data frame; The access point sends a multicast feedback trigger frame, where the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly; When the access point detects no energy on the first subcarrier and the second subcarrier, determining that the first station does not correctly decode the multicast data frame; Alternatively, the access point determines that the first station has not correctly decoded the multicast data frame when energy is detected on the second subcarrier; The first subcarrier is a subcarrier in a first subcarrier set that is associated with the first site, the second subcarrier is a subcarrier in a second subcarrier set that is associated with the first site, and the first site is any one of the multiple sites.

2. The method according to claim 1, characterized in that When the multicast data frame is an aggregated media access control protocol data unit AMPDU, the method further includes: The access point sends a block confirmation request trigger frame, where the block confirmation request trigger frame is used to schedule at least one second station to feed back a sequence number index of a media access control protocol data unit MPDU that is incorrectly decoded in the AMPDU on a resource unit RU associated with each second station, where the second station is a station among the multiple stations that does not correctly decode the AMPDU; The access point receives a block confirmation frame from the at least one second station on a RU associated with each of the at least one second stations, where the block confirmation frame is used to indicate an MPDU with a decoding error in the AMPDU.

3. A multicast feedback method, characterized in that: The method comprises: The first station receives a multicast data frame from an access point; The first station receives a multicast feedback trigger frame from the access point, where the multicast feedback trigger frame is used to schedule multiple stations in the multicast group to feedback whether the multicast data frame is decoded correctly; When the multiple sites include the first site and the first site fails to correctly decode the multicast data frame, the first site sends a multicast feedback report frame to the access point on a second subcarrier, where the second subcarrier is a subcarrier in a second subcarrier set associated with the first site.

4. The method according to claim 3, characterized in that When the multicast data frame is an aggregated media access control protocol data unit AMPDU, the method further includes: The first station receives a block confirmation request trigger frame from the access point, where the block confirmation request trigger frame is used to schedule the first station to feed back a sequence number index of a media access control protocol data unit MPDU with a decoding error in the AMPDU on a resource unit RU associated with the first station; The first station sends a block confirmation frame to the access point on the RU associated with the first station, where the block confirmation frame is used to indicate an MPDU with a decoding error in the AMPDU.

5. The method according to claim 2 or 4, characterized in that: The multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, where the duration of the first NAV is the sum of the following multiple items: the duration of a multicast feedback report frame, the duration of a block confirmation request trigger frame, the duration of a block confirmation frame, and a short frame interval SIFS, and the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

6. The method according to claim 1 or 3, characterized in that: The multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, where the duration of the first NAV is the sum of the duration of the multicast feedback report frame and a short frame interval SIFS, and the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

7. The method according to any one of claims 1 to 4, characterized in that: The multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is a multicast retransmission confirmation request.

8. The method according to any one of claims 1 to 4, characterized in that: The multicast feedback trigger frame includes a second field, and the second field is used to indicate the multicast data frame.

9. The method according to claim 8, characterized in that The second field includes a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the start data frame in the multicast data frame, and the second subfield is used to carry the sequence number index of the end data frame in the multicast data frame.

10. A multicast feedback method, characterized in that: The method comprises: The access point sends a multicast data frame; The access point sends a multicast feedback trigger frame, where the multicast feedback trigger frame is used to configure at least one resource unit RU, where the RU is used for stations in the multicast group to transmit a block confirmation frame of the multicast data frame during an uplink orthogonal frequency division multiple access random access (UORA) process; The access point receives a block confirmation frame from the first site during the UORA process through the first RU, and the block confirmation frame is used to indicate a data frame with decoding errors in the multicast data frame. The multicast data frame is an aggregate media access control protocol data unit AMPDU, and the first RU is one of the at least one RU.

11. A multicast feedback method, characterized in that: The method comprises: The first station receives a multicast data frame from an access point; The first station receives a multicast feedback trigger frame from the access point, where the multicast feedback trigger frame is used to configure at least one resource unit RU, where the RU is used for stations in the multicast group to perform uplink orthogonal frequency division multiple access random access UORA, where the UORA is used to transmit a block confirmation frame of the multicast data frame; When the first site fails to correctly decode the multicast data frame, a block confirmation frame of the multicast data frame is sent to the access point through the first RU in the UORA process, wherein the block confirmation frame is used to indicate a data frame with decoding errors in the multicast data frame, the multicast data frame is an aggregate media access control protocol data unit AMPDU, and the first RU is one of the at least one RU.

12. The method according to claim 11, characterized in that The first station sends a block confirmation frame of the multicast data frame to the access point in the UORA process through the first RU, including: The first station selects a random number in the contention window, and when the random number is less than or equal to the total number of the at least one RU, selects the first RU from the at least one RU; The first station sends a block confirmation frame of the multicast data frame to the access point on the first RU.

13. The method according to any one of claims 10 to 12, characterized in that: The multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is uplink orthogonal frequency division multiple access random access-negative acknowledgement polling.

14. A communication device, characterized in that: The communication device comprises: a processing module and a transceiver module: The transceiver module is used to send multicast data frames; The transceiver module is further used to send a multicast feedback trigger frame, where the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly; The processing module is used to determine that the first station has not correctly decoded the multicast data frame when no energy is detected on the first subcarrier and the second subcarrier; Alternatively, the processing module is used to determine that the first station has not correctly decoded the multicast data frame when energy is detected on the second subcarrier; The first subcarrier is a subcarrier in a first subcarrier set that is associated with the first site, the second subcarrier is a subcarrier in a second subcarrier set that is associated with the first site, and the first site is any one of the multiple sites.

15. The communication device according to claim 14, characterized in that: When the multicast data frame is an aggregated media access control protocol data unit AMPDU, The transceiver module is further used to send a block confirmation request trigger frame, wherein the block confirmation request trigger frame is used to schedule at least one second station to feedback the sequence number index of the media access control protocol data unit MPDU with a decoding error in the AMPDU on the respective associated resource units RU, and the second station is a station among the multiple stations that does not correctly decode the AMPDU; The transceiver module is also used to receive a block confirmation frame from the at least one second site on the RU associated with each of the at least one second sites, and the block confirmation frame is used to indicate an MPDU with a decoding error in the AMPDU.

16. A communication device, characterized in that: The communication device comprises: a processing module and a transceiver module; The transceiver module is used to receive multicast data frames from the access point; The transceiver module is further used to receive a multicast feedback trigger frame from the access point, where the multicast feedback trigger frame is used to schedule multiple sites in the multicast group to feedback whether the multicast data frame is decoded correctly; The transceiver module is further configured to send a multicast feedback report frame to the access point on a second subcarrier when the processing module determines that the multiple sites include the communication device and the communication device fails to correctly decode the multicast data frame, wherein the second subcarrier is a subcarrier in a second subcarrier set associated with the communication device.

17. The communication device according to claim 16, characterized in that: When the multicast data frame is an aggregated media access control protocol data unit AMPDU, The transceiver module is further used to receive a block confirmation request trigger frame from the access point, wherein the block confirmation request trigger frame is used to schedule the communication device to feedback a sequence number index of a media access control protocol data unit MPDU with a decoding error in the AMPDU on a resource unit RU associated with the communication device; The transceiver module is further used to send a block confirmation frame to the access point on the RU associated with the communication device, and the block confirmation frame is used to indicate the MPDU with decoding error in the AMPDU.

18. The communication device according to claim 15 or 17, characterized in that: The multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, where the duration of the first NAV is the sum of the following multiple items: the duration of a multicast feedback report frame, the duration of a block confirmation request trigger frame, the duration of a block confirmation frame, and a short frame interval SIFS, and the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

19. The communication device according to claim 14 or 16, characterized in that: The multicast feedback trigger frame includes a third field, where the third field is used to indicate a first network allocation vector NAV, where the duration of the first NAV is the sum of the duration of the multicast feedback report frame and a short frame interval SIFS, and the multicast feedback report frame is a reply frame of the multicast feedback trigger frame.

20. The communication device according to any one of claims 14 to 17, characterized in that: The multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is a multicast retransmission confirmation request.

21. The communication device according to any one of claims 14 to 17, characterized in that: The multicast feedback trigger frame includes a second field, and the second field is used to indicate the multicast data frame.

22. The communication device according to claim 21, characterized in that The second field includes a first subfield and a second subfield, the first subfield is used to carry the sequence number index of the start data frame in the multicast data frame, and the second subfield is used to carry the sequence number index of the end data frame in the multicast data frame.

23. A communication device, characterized in that: The communication device comprises: a processing module and a transceiver module; The processing module is used to generate a multicast data frame and a multicast feedback trigger frame; The transceiver module is used to send multicast data frames; The transceiver module is further used to send a multicast feedback trigger frame, the multicast feedback trigger frame is used to configure at least one resource unit RU, and the RU is used for sites in the multicast group to transmit a block confirmation frame of the multicast data frame during an uplink orthogonal frequency division multiple access random access UORA process; The transceiver module is also used to receive a block confirmation frame from the first site in the UORA process through the first RU, and the block confirmation frame is used to indicate a data frame with decoding errors in the multicast data frame. The multicast data frame is an aggregate media access control protocol data unit AMPDU, and the first RU is one of the at least one RU.

24. A communication device, characterized in that: The communication device comprises: a processing module and a transceiver module; The transceiver module is used to receive multicast data frames from the access point; The transceiver module is further used to receive a multicast feedback trigger frame from the access point, the multicast feedback trigger frame is used to configure at least one resource unit RU, the RU is used for sites in the multicast group to perform uplink orthogonal frequency division multiple access random access UORA, and the UORA is used to transmit a block confirmation frame of the multicast data frame; The transceiver module is used to send a block confirmation frame of the multicast data frame to the access point through the first RU in the UORA process when the processing module fails to correctly decode the multicast data frame, the block confirmation frame is used to indicate a data frame with decoding errors in the multicast data frame, the multicast data frame is an aggregate media access control protocol data unit AMPDU, and the first RU is one of the at least one RU.

25. The communication device according to claim 24, characterized in that The processing module is configured to select a random number in the contention window, and when the random number is less than or equal to the total number of the at least one RU, select the first RU from the at least one RU; The transceiver module is used to send a block confirmation frame of the multicast data frame to the access point on the first RU.

26. The communication device according to any one of claims 23 to 25, characterized in that: The multicast feedback trigger frame includes a first field. When the value of the first field is a first value, it indicates that the type of the multicast feedback trigger frame is uplink orthogonal frequency division multiple access random access-negative acknowledgement polling.

27. A communication device, characterized in that: The communication device comprises: a processor and a communication interface; The communication interface is used to communicate with modules outside the communication device; The processor is used to execute computer-executable instructions so that the communication device executes the method according to any one of claims 1 to 9, or so that the communication device executes the method according to any one of claims 10 to 13.

28. A computer-readable storage medium, characterized in that: The method comprises instructions, which, when executed on a communication device, enable the communication device to execute the method according to any one of claims 1 to 9, or enable the communication device to execute the method according to any one of claims 10 to 13.

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