Channel detection method and device

Abstract

The embodiment of the present application provides a channel detection method and device, which relates to the field of communications. The method includes: a station STA receives a channel detection frame sent by multiple access points AP; the STA performs channel detection based on the channel detection frame to obtain channel state information of each AP; the STA sends a channel measurement report frame, the channel measurement report frame includes the channel state information of some APs among the multiple APs and the identifiers of these APs, and the channel measurement report frame is also used to indicate that these APs are selected to participate in cooperative transmission. Using the channel measurement report frame to indicate the APs selected to participate in cooperative transmission can not only feedback channel state information, but also save signaling overhead.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of communications, and in particular to a channel detection method and device. Background Art

[0002] With the development of wireless networks and the increasing popularity of wireless local area network (WLAN) technology, the deployment of WLAN devices has become increasingly dense. As wireless access points (APs) are easy to deploy, the frequency of AP applications is increasing. However, as the density of AP deployment increases, it also brings about the problem of inter-cell interference. How to reduce inter-cell interference and improve user service quality through collaboration between APs has become an urgent problem to be solved.

[0003] The premise of cooperation between APs is to establish a cooperative relationship based on channel state information. In the prior art, the channel detection of APs can refer to the channel detection process of 802.11ac, such as Figure 1 As shown. Specifically, the AP first sends a Null Data Packet Announcement (NDPA) frame to notify the station (STA) that needs to perform channel detection and the relevant channel detection parameters, and then broadcasts the NDP frame after a short inter-frame space (SIFS), in which the NDP frame does not carry the data field. The STA can perform channel estimation on the AP based on the received NDP and generate a beamforming report (BFR). Subsequently, the AP sends a beamforming report poll (BF Report Poll, BFRP) to the STA to request channel status information that has not been fed back or has been fed back incorrectly from one or more STAs.

[0004] In 802.11ax, a multi-user uplink transmission mechanism is introduced. The AP can instruct multiple STAs to upload beamforming reports at the same time to further improve the efficiency of channel detection. The beamforming report in the existing technology contains a multiple input multiple output (MIMO) control field and a beamforming report field. The MIMO control field may include but is not limited to: bandwidth, number of transmit antennas, number of receive antennas and other control information. For example, the structure of the MIMO control field can be as follows: Figure 2 shown.

[0005] However, in 802.11ac and 802.11ax, both use a single AP and multiple STAs for channel detection. For the channel detection method of multiple APs, a current technical solution is to send NDP frames to the master AP and the slave AP, so that the STA performs channel detection based on the NDP frame and obtains channel state information. Subsequently, the master AP needs to obtain the channel state information of all APs and select a collaborative AP based on the channel state information. Obviously, selecting a collaborative AP based on the channel state information of all APs will result in a large feedback overhead of the channel state information, resulting in low efficiency. Summary of the invention

[0006] The present application provides a channel detection method and device, which can implement a collaborative AP selection method that saves channel state information feedback overhead.

[0007] This application adopts the following technical solutions:

[0008] In a first aspect, an embodiment of the present application provides a channel detection method, which may include: a STA receives a channel detection frame sent by n APs, where n is an integer greater than 1. Then, the STA may perform channel detection on the channels of the n APs based on the received channel detection frame, and obtain the channel state information of each AP. In addition, the STA sends a channel measurement report frame, wherein the channel measurement report frame includes the channel state information of m target APs among the n APs and the identifiers of the m target APs, and the channel measurement report frame can also be used to indicate that m target APs are selected to participate in collaborative transmission, and m is an integer greater than 1 and less than or equal to n.

[0009] Through the above method, STA can select cooperative AP based on channel state information. In addition, STA can inform AP whether it is selected to participate in cooperative transmission by feeding back channel state information. Accordingly, AP can also confirm whether it is selected to participate in cooperative transmission based on whether channel state information is obtained. And, AP that does not obtain channel state information can determine that the channel state between it and STA is poor, thereby providing an AP selection method that saves channel detection feedback overhead.

[0010] In a possible implementation manner, the method may further include: the STA sends indication information, where the indication information may be used to indicate that (nm) non-target APs are not selected to participate in the cooperative transmission.

[0011] Through the above manner, the STA can notify the non-target AP that it is not selected to participate in the cooperative transmission by feeding back indication information.

[0012] In one possible implementation, the indication information may include channel quality information of (nm) non-target APs and identifiers of (nm) non-target APs; or, the indication information may include unselected indication information and identifiers of (nm) non-target APs, the unselected indication information is used to indicate that (nm) non-target APs are not selected, and the channel quality information is used to indicate the channel quality of the channel between the non-target AP and the STA.

[0013] Through the above method, the STA can feed back channel quality information to the non-target AP, or feed back non-selection indication information to the non-target AP to inform the non-target AP that it is not selected to participate in the collaborative transmission. Different from the existing technology that requires the feedback of channel status information required by all APs participating in channel detection, this application effectively saves channel overhead and improves resource utilization.

[0014] In a possible implementation, before sending the channel measurement report frame, the method further includes: the STA sending or receiving a feedback type indication, where the feedback type indication is used to indicate the type of channel state information fed back by the STA, and the type of channel state information fed back by the STA includes: selective feedback and non-selective feedback.

[0015] In the present application, the feedback type indication may be sent by a STA or an AP. The STA and / or the AP may notify the STA, or the AP, or the AP and the STA by sending a feedback type indication, that the STA will select the target AP and selectively feed back the channel state information.

[0016] In a possible implementation manner, the selective feedback means that the STA feeds back the channel state information of some APs among n APs, and the non-selective feedback means that the STA feeds back the channel state information of each AP among the n APs.

[0017] In the above manner, STA and / or AP can know whether the current feedback process is selective feedback before STA feedback. If it is selective feedback, AP can confirm that it is selected to participate in cooperative transmission when channel state information is obtained, and AP can confirm that it is not selected when channel state information is not obtained. In the case of non-selective feedback, AP and STA can provide feedback in a conventional feedback manner.

[0018] In a possible implementation, the channel measurement report frame includes: a multiple-input multiple-output control field, and a feedback type field of the multiple-input multiple-output control field is a reserved value, which is used to indicate that the type of the STA feedback channel state information is selective feedback.

[0019] By setting the reserved value in the feedback type field, the AP and the STA determine that the feedback mode of the channel state information is selective feedback to distinguish it from other non-selective feedback.

[0020] In one possible implementation, the channel state information of m target APs meets a preset condition, wherein, if the collaborative transmission is a joint transmission, then the m APs with the best channel state information among the n APs meet the preset condition; if the collaborative transmission is a collaborative beamforming transmission, then the p APs with the best channel state information among the n APs and the q APs with the worst channel state information meet the preset condition, wherein the sum of p and q is equal to m.

[0021] Through the above manner, it is achieved that the STA can determine the AP corresponding to the channel state that meets the preset conditions according to different cooperative transmission modes.

[0022] In a possible implementation, the method also includes: the STA receives first data sent by the main AP, wherein the first data is data shared between m target APs, and the main AP is included in the m target APs; if the STA fails to receive the first data, the STA sends a retransmission request frame to p retransmission APs among the m target APs, and the retransmission request frame is used to instruct the p retransmission APs to resend the first data, where p is an integer greater than or equal to 1 and less than or equal to m.

[0023] Through the above method, a data retransmission method in cooperative transmission is implemented. When the STA fails to receive the first data, it can select p retransmission APs and request the retransmission APs to resend the first data.

[0024] In one possible implementation, the retransmission request frame includes a destination address field, a retransmission AP information field, a retransmission mode field, and a sending address indication field; wherein the destination address field is a broadcast address or the address information of the retransmission AP; the retransmission AP information field includes identification information of the retransmission AP; the retransmission mode field is used to indicate whether to adopt joint transmission to retransmit the first data; and the sending address indication field is used to indicate that the first data carries the address information of the main AP.

[0025] In the above manner, the STA may instruct the retransmission AP to send the first data through the retransmission request frame. Optionally, the retransmitted first data may include address information carried in the sending address indication field.

[0026] In one possible implementation, if the p retransmitting APs are not the main AP, the method also includes: receiving first data retransmitted by the retransmitting AP, wherein the first data includes address information of the main AP; performing joint soft decoding based on the first data retransmitted by the retransmitting AP and the first data sent by the main AP to obtain the first data after joint soft decoding.

[0027] Through the above method, STA can select an AP other than the main AP as the retransmitting AP, and when the retransmitting AP sends the first data, the first data can carry the address information of the main AP, or the AP that sent the first data last time, so that STA can perform joint soft decoding on the same data (first data) received twice or more, so as to improve the decoding success rate.

[0028] In a second aspect, an embodiment of the present application provides a channel detection method, which may include: an AP sends a channel detection frame, where the channel detection frame is used by a station STA to perform channel detection based on the channel detection frame and obtain channel state information; the access point receives feedback information sent by the STA;

[0029] Based on the feedback information, the AP determines whether it is selected by the STA to participate in the cooperative transmission.

[0030] In one possible implementation, the step of determining whether the AP is selected by the STA to participate in collaborative transmission based on feedback information may include: receiving a channel measurement report frame fed back by the STA, and identifying whether the channel measurement report frame includes identification information and channel status information of the AP; if the identification information and channel status information are identified, determining that the AP is selected to participate in collaborative transmission.

[0031] In one possible implementation, the step of determining whether the AP is selected by the STA to participate in collaborative transmission based on feedback information may also include: the AP receives indication information sent by the STA, the indication information being used to indicate that the AP is not selected to participate in the collaborative transmission; and the AP determines, based on the indication information, that the AP is not selected to participate in the collaborative transmission.

[0032] In a possible implementation, the indication information includes channel quality information of the AP and an identifier of the AP; or the indication information includes unselected indication information and an identifier of the AP, and the unselected indication information is used to indicate that the AP is not selected.

[0033] In a possible implementation, before the STA feeds back the channel measurement report frame, it also includes: the AP sends or receives a feedback type indication, the feedback type indication is used to indicate the type of STA feedback channel state information, and the type of STA feedback channel state information includes: selective feedback and non-selective feedback.

[0034] In a possible implementation, the method also includes: the AP receives the first data sent by the main AP to the AP and the STA; the AP receives the retransmission request frame sent by the STA, wherein the retransmission request frame is sent to the AP after the STA fails to receive the first data, and the retransmission request frame is used to instruct the AP to resend the first data; and the first data is sent to the STA.

[0035] In a possible implementation, the retransmission request frame includes a sending address indication field for indicating address information of a primary AP that sends the first data, and the method further includes: the AP sends the first data including the address information of the primary AP to the STA.

[0036] In a third aspect, an embodiment of the present application provides a communication device applied to a STA, and the device may include: a transceiver module and an acquisition module. The transceiver module may be used to receive channel detection frames sent by n APs, where n is an integer greater than 1; the acquisition module may be used to perform channel detection based on the channel detection frame to obtain channel state information of each AP; the transceiver module may also be used to send a channel measurement report frame, where the channel measurement report frame includes channel state information of m target APs among the n APs and identifiers of the m target APs, and the channel measurement report frame is also used to indicate that m target APs are selected to participate in collaborative transmission, where m is an integer greater than 1 and less than or equal to n.

[0037] In a possible implementation manner, the transceiver module may be further configured to send indication information, where the indication information is used to indicate that (nm) non-target APs are not selected to participate in the collaborative transmission.

[0038] In one possible implementation, the indication information includes channel quality information of (nm) non-target APs and identifiers of (nm) non-target APs; or, the indication information includes unselected indication information and identifiers of (nm) non-target APs, the unselected indication information is used to indicate that (nm) non-target APs are not selected, and the channel quality information is used to indicate the channel quality of the channel between the non-target AP and the STA.

[0039] In a possible implementation, the receiving module is further used to: send or receive a feedback type indication, where the feedback type indication is used to indicate the type of STA feedback channel state information, and the type of STA feedback channel state information includes: selective feedback and non-selective feedback.

[0040] In a possible implementation manner, the selective feedback means that the STA feeds back the channel state information of some APs among n APs, and the non-selective feedback means that the STA feeds back the channel state information of each AP among the n APs.

[0041] In a possible implementation, the channel measurement report frame includes: a multiple-input multiple-output control field, and a feedback type field of the multiple-input multiple-output control field is a reserved value, which is used to indicate that the type of the STA feedback channel state information is selective feedback.

[0042] In one possible implementation, the channel state information of m target APs meets a preset condition, wherein, if the collaborative transmission is a joint transmission, then the m APs with the best channel state information among the n APs meet the preset condition; if the collaborative transmission is a collaborative beamforming transmission, then the p APs with the best channel state information among the n APs and the q APs with the worst channel state information meet the preset condition, wherein the sum of p and q is equal to m.

[0043] In one possible implementation, the transceiver module is also used to: receive first data sent by a main AP, wherein the first data is data shared between m target APs, and the main AP is included in the m target APs; if the STA fails to receive the first data, a retransmission request frame is sent to p retransmission APs among the m target APs, and the retransmission request frame is used to instruct the p retransmission APs to resend the first data, where p is an integer greater than or equal to 1 and less than or equal to m.

[0044] In one possible implementation, the retransmission request frame includes a destination address field, a retransmission AP information field, a retransmission mode field, and a sending address indication field; wherein the destination address field is a broadcast address or the address information of the retransmission AP; the retransmission AP information field includes identification information of the retransmission AP; the retransmission mode field is used to indicate whether to adopt joint transmission to retransmit the first data; and the sending address indication field is used to indicate that the first data carries the address information of the main AP.

[0045] In one possible implementation, if the p retransmitting APs are not the main AP, the transceiver module is also used to: receive the first data retransmitted by the retransmitting AP, wherein the first data includes the address information of the main AP; accordingly, the STA also includes a decoding module, which is used to perform joint soft decoding based on the first data retransmitted by the retransmitting AP and the first data sent by the main AP, and obtain the first data after joint soft decoding.

[0046] In the fourth aspect, an embodiment of the present application provides a communication device applied to an AP, including: a transceiver module and a processing module, wherein the transceiver module can be used to send a channel detection frame, and the channel detection frame is used for the STA to perform channel detection based on the channel detection frame and obtain channel status information. The transceiver module is also used to receive feedback information sent by the STA; the processing module can be used to determine whether the AP is selected by the STA to participate in collaborative transmission based on the feedback information.

[0047] In one possible implementation, the transceiver module is also used to receive the channel measurement report frame fed back by the STA, and the processing module is further used to identify whether the channel measurement report frame includes the AP's identification information and channel status information; if the identification information and channel status information are identified, the processing module determines that the AP is selected to participate in the collaborative transmission.

[0048] In a possible implementation, the transceiver module is further used to receive indication information sent by the STA, where the indication information is used to indicate that the AP is not selected to participate in the collaborative transmission; the processing module is further used to determine that the AP is not selected to participate in the collaborative transmission based on the indication information.

[0049] In a possible implementation, the indication information includes channel quality information of the AP and an identifier of the AP; or the indication information includes unselected indication information and an identifier of the AP, and the unselected indication information is used to indicate that the AP is not selected.

[0050] In a possible implementation, the transceiver module is further used to send or receive a feedback type indication, where the feedback type indication is used to indicate the type of STA feedback channel state information, and the types of STA feedback channel state information include selective feedback and non-selective feedback.

[0051] In a possible implementation, the transceiver module is also used to: receive the first data sent by the main AP to the AP and the STA; receive the retransmission request frame sent by the STA, wherein the retransmission request frame is sent by the STA to the AP after failing to receive the first data, and the retransmission request frame is used to instruct the AP to resend the first data; and send the first data to the STA.

[0052] In a possible implementation, the retransmission request frame includes a sending address indication field for indicating address information of a main AP that sends the first data, and the transceiver module is further used for: the AP sends the first data including the address information of the main AP to the STA.

[0053] In a fifth aspect, an embodiment of the present application provides a device, which may be a STA device or a chip in a STA. The device has the function of implementing the above-mentioned first aspect related to STA. The function may be implemented by hardware or by executing corresponding software by hardware. The hardware or software includes one or more units corresponding to the above-mentioned functions.

[0054] In a possible implementation, when the device is a STA, the STA includes: a processor and a transceiver, wherein the processor is configured to support the STA to perform corresponding functions in the above aspects. The transceiver is used to support communication between the STA and the AP, and to send information or instructions involved in the above method to the AP. Optionally, the STA may also include a memory, which is coupled to the processor and stores program instructions and data necessary for the STA.

[0055] In a possible implementation, the device includes: a processor, a baseband circuit, a radio frequency circuit, and an antenna. The processor is used to control the functions of each circuit part, and the baseband circuit is used to generate various signaling and messages, such as cache indication messages, which are sent to the AP via the antenna after being processed by the radio frequency circuit such as analog conversion, filtering, amplification, and up-conversion. Optionally, the device may also include a memory, which stores the necessary program instructions and data of the STA.

[0056] In one possible implementation, the device may include a processor and a modem. The processor can be used to run instructions or an operating system to control STA functions. The modem can encapsulate, encode, decode, modulate, demodulate, and equalize data according to the protocol to generate signaling information, such as a channel detection report frame, to support the STA to perform the corresponding functions in the first aspect above.

[0057] In a possible implementation, when the device is a chip in a STA, the chip includes: a processing module and a transceiver module. The processing module may be, for example, a processor. For example, the processor is used to generate various messages and signaling, and encapsulate various messages according to the protocol, and then encode, modulate, amplify, etc. The processor may also be used to demodulate, decode, and obtain signaling and messages after decapsulation. The transceiver module may be, for example, an input / output interface, a pin or a circuit on the chip. The processing module may execute computer execution instructions stored in a storage unit to support the STA to perform corresponding functions in the above aspects. Optionally, the storage unit may be a storage unit in the chip, such as a register, a cache, etc. The storage unit may also be a storage unit located outside the chip in the STA, such as a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM), etc.

[0058] In a possible implementation, the device includes a processor, the processor is coupled to a memory, and reads instructions in the memory and executes the method involving STA in the first aspect according to the instructions. The memory may be located inside the processor or outside the processor.

[0059] Among them, the processor mentioned in any of the above places can be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of programs of the above-mentioned channel detection methods.

[0060] In a sixth aspect, the present application provides a device, which may be an AP or a chip in an AP. The device has the function of implementing the AP in the second aspect. The function may be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more units corresponding to the above functions.

[0061] In a possible implementation, when the device is an AP, the AP includes: a processor and a transceiver, wherein the processor is configured to support the AP to perform corresponding functions in the above method. The transceiver is used to support communication between APs or between APs and stations, and receive information or instructions involved in the above method sent by STAs, such as channel measurement report frames, etc. Optionally, the AP may also include a memory, which is used to couple with the processor and store program instructions and data necessary for the AP.

[0062] In a possible implementation, the device includes: a processor, a baseband circuit, a radio frequency circuit and an antenna. The processor is used to control the functions of each circuit part, and the radio frequency circuit can perform digital conversion, filtering, amplification and down-conversion on the signaling sent by the STA received via the antenna, and then decode it through the baseband circuit and decapsulate it according to the protocol to obtain the signaling information. Optionally, the device also includes a memory, which stores the necessary program instructions and data of the AP.

[0063] In one possible implementation, the device includes a processor and a modem. The processor can be used for instructions or an operating system to control AP functions. The modem can encapsulate, encode, decode, modulate, demodulate, and equalize data according to the protocol to generate a channel detection frame, or parse a channel measurement report frame, etc., to support the AP to perform the corresponding functions in the above-mentioned second aspect.

[0064] In a possible implementation, when the device is a chip in an AP, the chip includes: a processing module and a transceiver module, the processing module may be, for example, a processor, which may be used to filter, demodulate, power amplify, decode, and other processes on the signaling received via the transceiver module, and the transceiver module may be, for example, an input / output interface, a pin, or a circuit on the chip. The processing module may execute computer-executable instructions stored in a storage unit to support the AP in performing the corresponding functions of the above-mentioned second aspect. Optionally, the storage unit may be a storage unit in the chip, such as a register, a cache, and the like, or a storage unit located outside the chip in the AP, such as a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM), and the like.

[0065] In a possible implementation, the device includes a processor, the processor is coupled to a memory, and reads instructions in the memory and executes the method described in the second aspect according to the instructions. The memory may be located inside the processor or outside the processor.

[0066] The processor mentioned in any of the above places may be a general-purpose central processing unit, a microprocessor, a specific application integrated circuit, or one or more integrated circuits for controlling the execution of programs of the above-mentioned channel detection methods.

[0067] In a seventh aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores instructions, and the instructions can be executed by one or more processors on a processing circuit. When the instructions are executed on a computer, the computer executes the method in any one of the first aspect or the second aspect or any possible implementation thereof.

[0068] In an eighth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, enables the computer to execute a method in any one of the first or second aspects above or any possible implementation thereof.

[0069] In a ninth aspect, the present application provides a chip system, which includes a processor for supporting a data sending device to implement the functions involved in the above aspects, such as generating or processing the data and / or information involved in the above aspects. In a possible design, the chip system also includes a memory, which is used to store program instructions and data necessary for the data sending device. The chip system can be composed of a chip, or it can include a chip and other discrete devices.

[0070] In a tenth aspect, an embodiment of the present application provides a wireless communication system, which includes at least one STA and at least one AP involved in the above aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 is a schematic diagram of a channel detection process shown as an example;

[0072] Figure 2 is a schematic diagram of a frame structure of a MIMO control field shown as an example;

[0073] Figure 3 This is one of the schematic diagrams of an application scenario provided in an embodiment of the present application;

[0074] Figure 4 It is one of the flow charts of a channel detection method provided in the application embodiment;

[0075] Figure 5 It is a schematic diagram of a frame structure of a declaration frame provided in an embodiment of the application;

[0076] Figure 6 It is a schematic diagram of a frame structure of a channel measurement report frame provided in an embodiment of the application;

[0077] Figure 7 It is one of the frame structure diagrams of an NDPA frame provided in the application embodiment;

[0078] Figure 8 It is one of the flow charts of a channel detection method provided in the application embodiment;

[0079] Fig. 9 It is a schematic diagram of a frame structure of an indication frame provided in an embodiment of the application;

[0080] Fig.10 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0081] Fig.11 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0082] Fig.12 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0083] Fig.13 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0084] Fig.14 It is one of the frame structure diagrams of an NDPA frame provided in the application embodiment;

[0085] Fig.15 It is one of the flow charts of a channel detection method provided in the application embodiment;

[0086] Fig.16 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0087] Fig.17 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0088] Fig.18 It is one of the frame structure diagrams of a beamforming report frame provided in an embodiment of the application;

[0089] Fig.19 It is one of the flow charts of a channel detection method provided in the application embodiment;

[0090] Fig. 20 It is a schematic diagram of a frame structure of a retransmission frame provided in an embodiment of the application;

[0091] Fig.21 It is a schematic diagram of a frame structure of a physical preamble provided in an embodiment of the application;

[0092] Fig. 22 This is one of the schematic diagrams of an application scenario provided in an embodiment of the present application;

[0093] Fig.23 One of the schematic block diagrams of a device on the STA side provided in an embodiment of the present application;

[0094] Fig.24 A second schematic block diagram of a device on the STA side provided in an embodiment of the present application;

[0095] Fig.25 One of the schematic block diagrams of an AP-side device provided in an embodiment of the present application;

[0096] Fig.26 A second schematic block diagram of an AP-side device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0097] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0098] The term "and / or" in this article is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0099] The terms "first" and "second" in the description and claims of the embodiments of the present application are used to distinguish different objects rather than to describe a specific order of objects. For example, a first target object and a second target object are used to distinguish different target objects rather than to describe a specific order of target objects.

[0100] In the embodiments of the present 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 the embodiments of the present 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.

[0101] In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more than two. For example, multiple processing units refer to two or more processing units; multiple systems refer to two or more systems.

[0102] Before describing the technical solution of the embodiment of the present application, the communication system of the embodiment of the present application is first described in conjunction with the accompanying drawings. Figure 3 , which is a schematic diagram of an application scenario provided in an embodiment of the present application. The application scenario includes AP1, AP2, AP3, and STA. In the specific implementation process of the embodiment of the present application, STA is a communication device with wireless transceiver function, for example, it can communicate with other network elements based on the 802.11 protocol. STA can also be called a user terminal, user device, access device, subscriber station, subscriber unit, mobile station, user agent, user equipment or other names, for example, it can be a computer, smart phone, tablet computer and other devices; AP is a communication device with wireless transceiver function that can provide services for STA, for example, it can communicate with other network elements based on the 802.11 protocol, for example, an access point in a WLAN communication system, a router, a switch, a micro base station or a small base station, etc. It should be noted that in actual applications, the number of APs is one or more, and the number of STAs can be one or more. Figure 3 The number of STAs and APs in the application scenario shown is only an illustrative example and is not limited in this application.

[0103] Combined with the above Figure 3 The application scenario schematic diagram shown below introduces the specific implementation plan of this application:

[0104] Specifically, in the present application, the STA can select a collaborative AP based on the channel state information after measuring the AP's channel, and notify each AP whether it is selected by sending channel state information. In other words, each AP can determine whether it is selected to participate in collaborative transmission based on whether it receives channel state information.

[0105] In the embodiment of the present application, the scenario in which the STA sends the channel state information it needs to the selected AP without feeding back any results to the unselected AP is recorded as scenario one. The scenario in which the STA sends the channel state information it needs to the selected AP and sends the unselected AP the channel state information that can indicate part of the channel state information but not all the channel state information it needs is recorded as scenario two. In the embodiment of the present application, the collaborative transmission process based on the channel state information and feedback results of the STA is recorded as scenario three. Figure 3 Provide detailed description of each scenario.

[0106] Scene 1

[0107] Combination Figure 3 ,like Figure 4 FIG. 1 is a flow chart of a channel detection method in an embodiment of the present application. Figure 4 middle:

[0108] Step 101: n APs send channel detection frames to STAs, where n is an integer greater than 1.

[0109] Optionally, in an embodiment of the present application, before sending a channel detection frame, the AP sends an NDPA frame to notify the STA to perform channel detection on the AP's channel. Optionally, both the master AP and the slave AP can send NDPA frames, that is, the APs can each send an NDPA frame and an NDP frame. Optionally, only one of the APs can send an NDPA frame, which is not limited in the present application.

[0110] For example, AP1 can send NDPA frames to inform STAs and APs participating in channel detection. For example, if the APs participating in channel detection include AP1, AP2, and AP3, AP1 broadcasts NDPA frames to notify STAs and APs participating in channel detection. Figure 3 The STAs in the channel detect the channels of AP1, AP2 and AP3.

[0111] For another example, AP1 may broadcast an NDPA frame to notify STA to perform channel detection based on the NDP frame sent by AP1. Subsequently, AP1 sends an NDP frame. Then, AP2 also broadcasts an NDPA frame to notify STA to perform channel detection based on the NDP frame sent by AP2. AP3 is similar.

[0112] Step 102: The STA performs channel detection on the channels of n APs to obtain channel status information.

[0113] Specifically, in the present application, for example: after receiving the NDP frame sent by AP1, AP2, and / or AP3, the STA may perform channel detection on the channels of AP1, AP2, and / or AP3 based on the NDP frame to obtain channel status information.

[0114] Optionally, the channel state information is information reflecting the channel conditions between the AP and the STA, and can characterize the characteristics of the channel between the AP and the STA. The AP can obtain the state of the downlink channel between the AP and the STA based on the channel state information fed back by the STA, and can communicate with the STA on the channel (send and receive signaling or data) based on the state of the channel.

[0115] Step 103: The STA selects m target APs from n APs according to the channel state information.

[0116] Specifically, in an embodiment of the present application, the STA may match the channel state information of each AP with a preset condition, wherein the AP whose channel state information satisfies the preset condition is the target AP, and the AP whose channel state information does not satisfy the preset condition is the non-target AP.

[0117] Optionally, if the collaborative transmission is a joint transmission, the preset condition may be: selecting the AP with the best channel state information. If the collaborative transmission is a collaborative beamforming transmission, the preset condition may be: selecting the AP with the best channel state information and the AP with the worst channel state information as the target AP. Optionally, when the collaborative transmission is a collaborative beamforming transmission and the AP associated with the STA has been selected, the m target APs may also be the APs with the worst channel state information. In one implementation, the best channel state information may refer to the channel state information being greater than or equal to an upper threshold, and the worst channel state information may refer to the channel state information being less than or equal to a lower threshold; in another implementation, the best channel state information may refer to the maximum channel state information, and the worst channel state information may refer to the minimum channel state information.

[0118] For example: if the cooperative transmission is joint transmission, the STA may select m APs with better channel status among n APs as target APs.

[0119] Optionally, if the cooperative transmission is a cooperative beamforming transmission, the STA may select m APs with poor channel status among n APs as target APs, and the selected m target APs will be associated with other STAs in the cooperative beamforming transmission. Optionally, if k APs (k is an integer greater than or equal to 1) have been selected for cooperative transmission with the STA, the STA selects m target APs from (nk) APs other than the k APs among the n APs. This reduces the channel interference between the m target APs and other STAs and the interference between the k APs and the STA. Figure 1 For example, when the main AP has been selected (taking AP1 as the main AP), the STA can select an AP with poorer channel state information (such as AP3) among AP2 and AP3 as the target AP, and the target AP will be associated with another STA (not shown in the figure). In the subsequent collaborative beamforming transmission, AP1 sends data 1 to the STA, and at the same time, AP3 sends data 2 to another STA.

[0120] Optionally, if the collaborative transmission is collaborative beamforming transmission, the STA can also select m APs with the best channel state information and the worst channel state information as target APs, where the ratio between the number of APs corresponding to the best detection results and the number of APs corresponding to the worst channel state information can be set according to actual needs. For example, when n=4, 2 target APs can be set to be selected, among which 1 AP with the best channel state information and 1 AP with the worst channel state information can be selected to perform collaborative beamforming transmission to provide services for the STA.

[0121] In the present application, when the STA selects the target AP according to the above preset conditions, after the STA obtains the channel status information of n APs, it selects the target AP and performs the subsequent feedback process. Optionally, the STA can also adopt an instantaneous judgment and feedback method. Specifically, the STA can perform channel detection on the AP's channel and obtain channel quality information. The AP can determine whether the state of the downlink channel is good or bad based on the channel quality information. Among them, if the state of the downlink channel is determined to be good (the specific judgment method will be described in the following embodiment), the AP selects the corresponding AP as the target AP and feeds back the channel status information to the target AP.

[0122] It should be noted that the channel quality information can be any indicator that can reflect the channel quality between the STA and the AP, but the channel quality information cannot enable the AP to obtain the channel characteristics required for data transmission through the downlink channel based on the indicator, that is, the AP can determine whether the state of the downlink channel is good or bad based on the channel quality information, but the AP cannot obtain all the channel characteristics required for data transmission through the downlink channel based on the channel quality information, and thus cannot perform the subsequent data transmission process. Compared with the channel state information, the acquisition method of the channel quality information is simpler and faster, so that the STA can determine whether the channel state of the AP meets the preset conditions after obtaining the channel quality information, or whether it can participate in the collaborative transmission as a target AP. The amount of information of the channel characteristics represented by the channel quality information is less than the amount of information of the channel characteristics represented by the channel state information. Optionally, the channel quality information includes but is not limited to: signal strength indication (Received Signal Strength Indication, RSSI), signal-to-noise ratio (Signal-to-Noise Ratio, SNR), signal to interference plus noise ratio (Signal to Interference plus Noise Ratio, SINR) or channel correlation, etc.

[0123] Optionally, if the collaborative transmission is a joint transmission, the preset condition may be: if the channel quality information of the AP is greater than or equal to a first threshold, it is determined that the preset condition is met. Optionally, if the collaborative transmission is a collaborative beamforming transmission, the preset condition may be: if the channel quality information of the AP is less than or equal to a second threshold, it is determined that the preset condition is met. It should be noted that the first threshold and the second threshold may be determined by protocol agreement, may be determined by the AP and then assigned to the STA, or may be determined by the STA itself, and the embodiments of the present application are not limited thereto.

[0124] Optionally, if the collaborative transmission is a joint transmission, the STA can set a first threshold and select the AP whose channel quality information is greater than or equal to the first threshold as the target AP. The channel quality information and the first threshold can be indicators such as RSSI, SNR, SINR or channel correlation. For example: when the STA measures the channel of AP2, the indicator obtained is RSSI. If the collaborative transmission is a joint transmission, the STA compares the RSSI with the preset RSSI (which can be set according to actual needs). If it is greater than or equal to the preset RSSI, AP2 is determined to be the target AP. The setting of other optional thresholds can be set according to actual needs, and this application does not limit it.

[0125] Optionally, if the collaborative transmission is collaborative beamforming transmission, the STA may set a second threshold and select an AP whose channel quality information is less than or equal to the second threshold as the target AP. The channel quality information and the second threshold may be indicators such as RSSI, SNR, SINR or channel correlation, and the second threshold may be the same as or different from the first threshold, which is not limited in this application.

[0126] Reference Figure 3 In step 103, for example, the STA selects AP1 and AP2 from among AP1, AP2, and AP3 as target APs participating in cooperative transmission, and AP3 is a non-target AP that is not selected for cooperative transmission.

[0127] Step 104: The STA sends a channel measurement report frame, which includes channel state information of m target APs among n APs and identifiers of the m target APs. The channel measurement report frame is also used to indicate that the m target APs are selected to participate in collaborative transmission.

[0128] Optionally, the channel measurement report frame may be a beamforming report frame, and the channel state information may be carried in a beamforming report field included in the beamforming report frame. The channel state information may be a compressed channel characteristic or an uncompressed channel characteristic. For example, the channel state information may be: a compressed beamforming report or an uncompressed beamforming report. Feedback in a compressed form may further reduce the overhead of channel state information feedback.

[0129] Specifically, in the present application, based on step 103, the STA may select m target APs to participate in the cooperative transmission. Subsequently, the STA may send a channel measurement report frame including the identification information of the target AP and the channel state information to the selected m target APs to notify the m APs that they are selected to participate in the cooperative transmission. Figure 4 For example, the STA sends a channel measurement report frame, wherein the channel measurement report frame includes the identification information of m target APs (including AP1 and AP2), and the channel state information of AP1 and AP2. In addition to being used to feedback the channel state information of AP1 and AP2, the channel measurement report frame can also be used to indicate that AP1 and AP2 are selected as target APs participating in collaborative transmission. Optionally, the STA can send m channel measurement report frames sequentially in a unicast manner, and one channel measurement report frame carries the channel measurement result and identification of a target AP. Accordingly, the AP that receives the channel measurement report frame can determine that it is selected to participate in collaborative transmission, and can obtain the corresponding channel state information from the channel measurement report frame.

[0130] Optionally, the STA can send a channel measurement report frame by broadcasting, wherein the channel measurement report frame includes the channel measurement results of m target APs and the identification information of m target APs. Accordingly, the AP that receives the broadcast channel measurement report frame can determine whether it is selected based on the identification information in the channel measurement report frame. Specifically, if the AP successfully matches its own identification information with the identification information in the channel measurement report frame, it can be determined that it is selected, and the AP can obtain the corresponding channel state information from the report frame; accordingly, if its own identification information fails to match the identification information in the channel measurement report frame, the AP is an AP that is not selected to participate in the collaborative transmission, and can be called a non-target AP. The following is a detailed description of the way in which the channel measurement report frame notifies the AP whether it is selected in unicast and broadcast modes:

[0131] 1) The channel measurement report frame is sent in unicast mode.

[0132] Specifically, the STA may feed back their channel measurement report frames to the m target APs respectively, and the channel measurement report frames include identification information of the target APs and channel state information.

[0133] Example: See Figure 3 , STA can send a channel measurement report frame to AP1, and the destination address of the frame is the address information of AP1. Optionally, the address information can be MAC address information. After listening to the channel measurement report frame, AP1 recognizes that the address information of the channel measurement report frame (that is, the identification information of the target AP described in the embodiment of the present application) matches the local address information of AP1. Then, AP1 receives the channel measurement report frame and recognizes that the channel measurement report frame includes the channel state information of AP1. Then, AP1 can determine that it is the target AP selected to participate in the collaborative transmission while obtaining the channel state information. It should be noted that the address information in the channel measurement report frame can be the identification information of the AP described in the present application, that is, when the AP recognizes that the identification information matches the local identification information (that is, the local address information) and the frame includes the channel state information, it can determine that it is the selected target AP. Optionally, the channel measurement report frame can also carry other identification information that can identify AP1 in addition to the address information, such as: Association Identifier (AID). Accordingly, after receiving the channel measurement report frame, AP1 can determine whether it is selected as the target AP by identifying whether the channel measurement report frame includes the AID of AP1 and the corresponding channel state information. In addition, the STA can send a channel measurement report frame to AP2, the destination address of which is the address information of AP2, and the channel measurement report frame includes the channel state information of AP2, so as to notify AP2 that it is selected to participate in the collaborative transmission.

[0134] Optionally, as described above, if the channel measurement report frame is sent in unicast mode, then for the unselected (nm) non-target APs, the STA can inform the non-target AP that it is not selected to participate in the collaborative transmission by not feeding back the channel measurement report frame to the non-target AP. That is to say, in this embodiment, if the AP does not receive the channel measurement report frame at the specified time, it can be determined that it has not been selected for parameter collaborative transmission. Optionally, the specified time can be a predetermined time after the AP sends the NDP frame, and the predetermined time can be set according to actual needs, for example: it can be SIFS, which is not limited in this application, or the specified time can also be a predetermined time after the NDP frames of all APs are sent. The specified time can be set according to actual needs, which is not limited in this application.

[0135] Optionally, in the present application, the channel measurement report frame may be a beamforming report frame, and the beamforming report frame includes but is not limited to: a MIMO control field and a beamforming report field. Optionally, the channel state information may be carried in the beamforming report field.

[0136] Optionally, in the present application, the MIMO control field may include information for indicating that the type of the STA feedback channel state information is selective feedback. Optionally, the information may be carried in the feedback type field in the MIMO control field. Optionally, the feedback type field may represent the information by setting a preset value. For example, the parameter value in the feedback type field may be set to 3 to indicate that the current feedback type is selective feedback.

[0137] It should be noted that the selective feedback described in this application means that the target AP is selected by the STA, and the STA only feeds back channel state information to some APs, such as the target AP (the selected AP). Conversely, non-selective feedback refers to other feasible feedback methods, such as the feedback method in which the STA feeds back channel state information to each of the n APs participating in channel detection. For example: Figure 1 As shown, AP1, AP2, and AP3 participate in channel detection, and non-selective feedback means that STA needs to feedback channel state information to AP1, AP2, and AP3. Selective feedback in this application means that STA can feedback channel state information to AP1 and AP2, but not to AP3.

[0138] It should be noted that in the non-selective feedback mode, the value of the feedback type field in the MIMO control field can be 0, 1, 2 or 3. Among them, 0, 1, and 2 are already occupied. This application can use the value 3 to indicate that the feedback type is selective feedback, or other fields or reserved bits in the MIMO control field can be used to indicate that the feedback type is selective feedback, which is not limited in this application.

[0139] 2) The channel measurement report frame is sent by broadcast.

[0140] Optionally, after the STA obtains the channel state information of the AP, it generates a channel measurement report frame. The destination address in the channel measurement report frame is a broadcast address. The channel occupancy can be further reduced and the channel overhead can be saved by broadcasting.

[0141] Specifically, the channel measurement report frame may include the identification information of the target AP and the channel state information. Optionally, the AP that receives the channel measurement report frame may match the local identification information with the identification information carried in the frame to determine whether it is the target AP. For example, if the match is successful, it can be determined that it is the target AP and extract the corresponding channel state information. On the contrary, if the match fails, it can be determined that it is a non-target AP and is not selected to participate in the collaborative transmission. Optionally, for example: if the channel measurement report frame is a beamforming report, the identification information of the AP may be carried in the MIMO control field, or the MIMO control field and the beamforming report field, or the beamforming report field. Optionally, the identification information of the AP may also be carried in other frames sent before the channel measurement report frame, and the AP identification information may be an AP sequence indication, which is used to indicate the position of the fields belonging to each AP in the beamforming report frame, and the AP may determine the position of its own beamforming report field in the channel measurement report frame according to the AP sequence indication, thereby obtaining its own channel state information. Optionally, the AP identification information or the AP sequence indication may be carried in an NDPA frame or a channel measurement report trigger frame.

[0142] Optionally, the channel measurement report frame may include multiple STA information fields (or may be called AP information fields), and each STA information field corresponds to the target AP one-to-one. Optionally, the identification information and channel state information of the AP may be carried in the STA information field accordingly. For example, the identification information and channel state information of AP1 may be carried in STA information field 1, and the identification information and channel state information of AP2 may be carried in STA information field 2. The AP can determine that the channel state information carried in the field is the channel state information it needs by reading the identification information in the STA field, and obtain it locally. Optionally, the identification information and channel state information of each AP in the channel measurement report frame can also be distinguished by a delimiter. The method for isolating the identification information and channel state information of different APs in the broadcast channel measurement report frame is not limited to the above-mentioned isolation method, and this application does not limit it.

[0143] Optionally, in the present application, in order to implement the selective feedback method described in the embodiments of the present application, the AP and the STA may also exchange feedback type indications so that both the AP and the STA are aware of the type of feedback. For example, the AP (referring to the main AP, such as AP1, or any AP, which is not limited in the present application) may send a feedback type indication to notify other APs and / or STAs to adopt a selective feedback method or a non-selective feedback method in the feedback process (the specific implementation methods of selective feedback and non-selective feedback are described above). Optionally, in the present application, the feedback type indication may also be sent by the STA, which is not limited in the present application.

[0144] Optionally, in the present application, the feedback type indication may be carried in a declaration frame. The declaration frame may be sent at any time before the STA feedback channel measurement report frame. Optionally, in the present application, the declaration frame may include a feedback type indication field for carrying the feedback type indication. Among them, the length of the feedback type indication field may be 2 bits. In an example, the value corresponding to the feedback type indication and its indication function are shown in Table 1. Of course, the different indication functions corresponding to different values ​​of the feedback type can be transformed.

[0145] Table 1

[0146]

[0147] Optionally, in this application, the frame structure of the declaration frame is as follows Figure 5 As shown, refer to Figure 5 , the declaration frame also includes but is not limited to: a frame control field, a receiving address field (or can be called a destination address field), a sending address field and other fields.

[0148] Optionally, in the present application, the feedback type indication may also be carried in a channel measurement report trigger frame sent by an AP (or may refer to a master AP, such as AP1). Optionally, the channel measurement report trigger frame may include a feedback type field, and the feedback type indication may be carried in the feedback type field. Figure 6 The frame structure diagram of the trigger frame is shown, wherein the length and parameter setting of the feedback type field can refer to the feedback type field in the declaration frame, which is not repeated here. In addition, the trigger frame also includes other fields (for example: frame control field, receiving address field and sending address indication field, etc., which are not repeated in this application.).

[0149] Optionally, in the present application, the feedback type indication may also be carried in the NDPA frame. Optionally, the feedback type indication may be carried in the STA information field in the NDPA frame to indicate that the feedback method adopted by the STA corresponding to the STA information field is selective feedback. Figure 7The figure shows a schematic diagram of the frame structure of the NDPA frame in the present application, wherein the NDPA includes multiple STA information fields, corresponding to STA1, STA2 and STA3 (not shown in the figure of the present application), and the STA information field corresponding to STA1 includes a feedback type indication field, the length of which can be 2 bits, and the setting of the parameter value can refer to Table 2, which is not repeated here.

[0150] Combination Figure 3 ,like Figure 8 FIG. 1 is a flow chart of a channel detection method in an embodiment of the present application. Figure 8 middle

[0151] Step 201: n APs send channel detection frames to STAs.

[0152] Step 202: The STA performs channel detection on the channels of n APs to obtain channel status information.

[0153] Step 203: The STA selects m target APs from n APs according to the channel state information.

[0154] Step 204: The STA sends a channel measurement report frame, which includes channel state information of m target APs among n APs and identifiers of the m target APs. The channel measurement report frame is also used to indicate that the m target APs are selected to participate in collaborative transmission.

[0155] Step 205: The STA sends an indication frame, which does not include channel state information of (nm) non-target APs.

[0156] Specifically, the STA may indicate through a channel measurement report frame that m target APs are selected to participate in the collaborative transmission, wherein the manner in which the STA sends the channel measurement report frame may refer to step 104 and will not be described in detail here. Further, the STA may also send an indication frame, which is used to indicate that (nm) non-target APs are not selected to participate in the collaborative transmission. For example: refer to Figure 3 Optionally, the STA sends a channel measurement report frame including identification information of AP1 and AP2 and channel state information, and the STA sends an indication frame, which does not include channel state information of a non-target AP (AP3).

[0157] Optionally, the indication frame may be a frame having a simple frame structure including only the destination address, the sending address and the feedback type field. For example, the structure of the indication frame may be as follows: Fig. 9 As shown, the channel overhead is further saved. For example: STA sends the indication frame to AP3, AP3 receives the indication frame, and recognizes that the indication frame does not contain channel state information, and then determines that AP3 is not selected to participate in the cooperative transmission.

[0158] Optionally, the indication frame may also have the same frame structure as the channel measurement report frame, for example, both are beamforming report frames. Different from the channel measurement report frame of the target AP, the channel measurement report field of the channel measurement report frame of the non-target AP does not include channel state information. For example: STA sends a channel measurement report frame, wherein the channel measurement report frame sent to AP1 and AP2 includes channel state information, and the channel measurement report frame sent to AP3 does not carry channel state information. Then, after AP3 recognizes that the channel measurement report frame does not carry the channel state information of AP3, it determines that it has not been selected to participate in collaborative transmission.

[0159] Optionally, the information carried in the indication frame and the information carried in the channel measurement report frame may be combined into one beamforming report frame and sent out.

[0160] An example: the indication frame is a separate beamforming report frame as an example for detailed description.

[0161] Optionally, the beamforming report frame sent by the STA to the non-target AP includes a MIMO control field, but does not include a beamforming report field for carrying channel state information. Optionally, the beamforming report frame sent by the STA to the non-target AP may include a MIMO control field and a beamforming report field, wherein the beamforming report field is empty, so that the AP that receives this type of beamforming report frame that does not include channel state information determines that it is not selected to participate in the collaborative transmission.

[0162] To implement the above feedback method, the beamforming report frame used in this application may include: a MIMO control field, a beamforming report field, and a selection information field. Among them, the MIMO control field can be used to carry control information of the AP. The control information includes but is not limited to: bandwidth, number of transmitting antennas, number of receiving antennas, etc. Optionally, the MIMO control field can be, for example, Figure 2 The beamforming report field includes but is not limited to: channel state information, etc. The selection information field includes but is not limited to: unselected indication information and / or channel quality information (SNR, RSSI, and / or channel correlation, etc.). The beamforming report frame may also include but is not limited to: a category field for identifying the type of the beamforming report frame, and an action indication field for indicating that a beamforming report frame is sent and the AP does not need to reply with a response frame.

[0163] As another example, the information carried in the indication frame and the information carried in the channel measurement report frame may also be combined into one beamforming report frame and sent out.

[0164] In one example, the fields and meanings that may be included in the beamforming report frame may be as shown in Table 2 or Table 3. It should be noted that, for different feedback forms, the beamforming report frame may not include all the fields in Table 2 or Table 3, but may adaptively include some of the fields therein.

[0165] Table 2

[0166]

[0167] Table 3

[0168]

[0169] The difference between Table 2 and Table 3 is that when the frame structure in Table 2 is used, the beamforming report frame includes one or more MIMO control fields, and each MIMO control field corresponds to an AP one-to-one, that is, one MIMO control field includes control information of the corresponding AP. When the frame structure in Table 3 is used, the beamforming report frame includes one MIMO control field, which carries control information of all APs.

[0170] The following first describes in detail the frame structure shown in Table 2, and the frame structure in Table 3 will be described in detail in the following embodiments. The structure of the beamforming report frame of the non-target AP (AP3) can be as follows: Fig.10 As shown. The beamforming report frame includes the MIMO control field of AP3 in Table 2, which is used to carry the control information of AP3. AP3 receives the beamforming report frame and recognizes that the beamforming report frame does not carry the beamforming report field, that is, does not carry the channel state information. Then, AP3 determines that it is not selected to participate in the collaborative transmission.

[0171] Optional, still refer to Fig.10 , the beamforming report frame of the non-target AP (AP3) may also include a MIMO control field and a beamforming report field, wherein the beamforming report field is empty, that is, does not include channel state information. Accordingly, AP3 receives the beamforming report frame and recognizes that the beamforming report field in the beamforming report frame does not include channel state information, then AP3 determines that it is not selected to participate in the collaborative transmission. Optionally, the beamforming report frame also includes the category field, action indication field, etc. in Table 2.

[0172] Optionally, in combination with Table 2, if the transmission mode of the beamforming report frame is broadcast, the beamforming report frame sent by the STA may include the MIMO control field and the beamforming report field of the target AP, as well as the MIMO control field of the non-target AP. For example: the frame structure of the beamforming report frame can also be as follows: Fig.11As shown. Among them, the beamforming report frame includes the MIMO control field (i.e., MIMO control field 1 in the figure) and beamforming report field (i.e., beamforming report field 1 in the figure) of AP1, the MIMO control field (i.e., MIMO control field 2 in the figure) and beamforming report field (i.e., beamforming report field 2 in the figure) of AP2, and the MIMO control field (i.e., MIMO control field 3 in the figure) of AP3. Optionally, the identification information of the AP may be carried in the MIMO control field and the beamforming report field, for example: AP1, AP2, and AP3 may obtain their respective corresponding fields by matching their respective identification information. Among them, AP1 and AP2 may identify and obtain information in the MIMO control field and the beamforming report field. If AP3 does not identify the beamforming report field of AP3, that is, does not obtain the channel state information, then AP3 may determine that it is not selected, and AP3 may obtain the control information in the MIMO control field.

[0173] Optionally, the identification information of the AP may also be carried in the MIMO control field instead of the beamforming report field. The AP may obtain the corresponding MIMO control field by matching the identification information in the MIMO control field, and determine that the subsequent field adjacent to the MIMO control field is its own beamforming report field. Alternatively, the AP may read the fields of the AP itself before reading the next field containing the identification information of other APs. For example, Fig.12 As shown, MIMO control field 1 includes identification information of AP1. Based on the identification information, AP1 can determine that MIMO control field 1 corresponds to AP1, obtain the control information therein, and continue to read the subsequent beamforming report field.

[0174] Optionally, the AP identification information (including target AP and non-target AP) can also be carried in other frames sent before the channel measurement report frame, to instruct the corresponding AP to obtain its own fields in the channel measurement report frame according to the order of the AP identification information. Optionally, the AP identification information can be carried in the NDPA frame or the channel measurement report trigger frame.

[0175] Optionally, the beamforming report frame may also include a MIMO control field and a beamforming report field of a target AP, and a MIMO control field and a beamforming report field of a non-target AP, wherein the beamforming report field of the non-target AP is empty.

[0176] It should be noted that the positions of the various fields in the frame structure described in this application are only illustrative examples and can be set according to actual needs, and this application does not limit them.

[0177] Optionally, in combination with Table 3, APs (AP1, AP2, and AP3) may also share a MIMO control field, that is, the control information of AP1, AP2, and AP3 may be carried in the MIMO control field. Optionally, the identification information of the AP may be carried in the MIMO control field in correspondence with the control information. Accordingly, the AP may identify the identification information and determine that the field after the identification information (the field before the next identification information) is its own control information. For example, the frame structure of the beamforming report frame may refer to Fig.13 Specifically, the beamforming report frame includes the MIMO control field of the AP, the beamforming report field of AP1 (i.e., beamforming report field 1 in the figure), and the beamforming report field of AP2 (i.e., beamforming report field 2 in the figure). Accordingly, AP1, AP2, and AP3 can read the MIMO control field to obtain their respective control information, wherein AP3 does not recognize the corresponding beamforming report field, that is, AP3 does not obtain the corresponding channel state information, and AP3 is determined not to be selected. Optionally, the identification information of the AP may also be carried in other frames sent before the channel measurement report frame, and the AP may obtain its own fields in the channel measurement report frame according to the order indicated by the identification information of the AP.

[0178] Optionally, in the present application, the STA may also compress the channel measurement report frame (e.g., beamforming report frame) to further reduce the channel overhead. Optionally, the STA compresses the beamforming report using a general or private algorithm. General algorithms include, but are not limited to, algorithms such as Moving Picture Experts Group (MPEG)-2, MPEG-4, H.264, Request For Comments (RFC) 1951, and RFC 1952. The specific compression method can refer to the existing technology, which is not limited in the present application. Accordingly, in the present application, the STA may send a compression indication field, which is used to indicate that the beamforming report field is compressed. Optionally, the compression indication field may be included in the beamforming report frame. The AP may decompress the compressed beamforming report field based on the indication of the compression indication field to obtain a beamforming report frame. Optionally, the NDPA frame sent by the AP may include a compression indication to notify other APs that the beamforming report is compressed and to notify the STA to compress the beamforming report. Optionally, the compression indication may be carried in the feedback type field in the NDPA frame, and its frame structure may refer to Fig.14 Optionally, the above frame compression method can also be applied to point-to-point transmission, for example, a signaling interaction process between STAs.

[0179] It should be noted that step 204 and step 205 can be executed simultaneously or sequentially, and the execution order is not limited. Optionally, the STA may first execute step 204 to send a channel measurement report frame to the target AP, and then execute step 205 to send an indication frame to the non-target AP; or, the STA may first execute step 205 and then execute step 204; or, the STA may execute step 204 and step 205 simultaneously.

[0180] In summary, according to the technical solution in the embodiment of the present application, STA can send a channel measurement report frame to notify the target AP that it is selected to participate in the collaborative transmission. STA does not send the channel state information of the unselected non-target AP to notify the non-target AP that it is not selected to participate in the collaborative transmission. STA can also send an indication frame that does not carry channel state information to the non-target AP to notify the non-target AP that it is not selected to participate in the collaborative transmission, thereby providing a channel detection method for collaborative AP selection performed by STA, and STA can selectively feedback channel state information to effectively save channel overhead, improve resource utilization, and realize the selection of collaborative AP.

[0181] Scene 2

[0182] Combination Figure 3 ,like Fig.15 FIG. 1 is a flow chart of a channel detection method in an embodiment of the present application. Fig.15 middle:

[0183] Step 301: n APs send channel detection frames to STAs.

[0184] Step 302: The STA performs channel detection on the channels of n APs to obtain channel status information.

[0185] Step 303: The STA selects m target APs from n APs according to the channel state information.

[0186] Step 304: The STA sends a channel measurement report frame, which includes channel state information of m target APs among n APs and identifiers of the m target APs. The channel measurement report frame is also used to indicate that the m target APs are selected to participate in collaborative transmission.

[0187] Step 305: The STA sends indication information, where the indication information includes channel quality information or unselected indication information.

[0188] Specifically, in the present application, the STA may indicate that m target APs are selected to participate in the collaborative transmission by sending a channel measurement report frame, wherein the manner in which the STA sends the channel measurement report frame may refer to step 104 and will not be described in detail here.

[0189] Further, the STA may also send indication information, which is used to indicate that (nm) non-target APs are not selected to participate in the collaborative transmission. Optionally, the indication information may be carried in a beamforming report frame. Alternatively, the indication information may also be carried in an indication frame, which has a simple frame structure, including: a sending address, a receiving address, and an indication field (the indication field carries the indication information).

[0190] Example: See Fig.15 Optionally, the STA sends a channel measurement report frame including identification information of AP1 and AP2 and channel state information, indicating that AP1 and AP2 are selected as target APs participating in collaborative transmission, and the STA sends indication information, which includes channel quality information of AP3 or unselected indication information, indicating that AP3 is not selected to participate in collaborative transmission.

[0191] Optionally, the indication information may include channel quality information, which is used for non-target APs to identify that the indication information only carries channel quality information but does not carry the channel state information requested by the AP, and to determine that the AP is not selected to participate in the collaborative transmission. In addition, the channel quality information can also reflect the quality of the channel. Accordingly, the AP can determine the channel quality between it and the STA based on the channel quality information. Optionally, the channel quality information can be indicators such as RSSI, SNR, and channel correlation. Optionally, the bit length of the channel quality information is less than the bit length of the total channel state information required by the AP, thereby further saving channel overhead.

[0192] Optionally, the indication information may also include unselected indication information, which is used for the non-target AP to determine that the AP is not selected to participate in the cooperative transmission when it recognizes that the indication frame includes the unselected indication information. Optionally, the length of the indication information may be 1 bit, thereby further saving channel overhead.

[0193] Combine the following Figure 3 , a detailed description is given by taking the example of indicating that the information is carried in a channel measurement report frame (or beamforming report frame).

[0194] Optionally, in the present application, the beamforming report frame may include two forms:

[0195] 1) One beamforming report frame can carry information of multiple APs.

[0196] 2) A beamforming report frame only carries the information of one AP.

[0197] For 1), optionally, the beamforming report frame may include channel state information of AP1 and AP2, and indication information of AP3, so that AP1 and AP2 are determined as selected target APs after identifying the channel state information, and AP3 is determined as an unselected non-target AP after identifying the indication information.

[0198] For example, the beamforming report frame includes a selection information field. Optionally, the indication information may be carried in the selection information field, so that AP3 can determine that it is not selected after identifying the selection information field. Fig.16 As shown, in Fig.16 In the beamforming report frame, the selection information field may include the identification information of AP3 and the indication information. After the local identification information of AP3 successfully matches the identification information in the selection information field, AP3 reads the indication information in the field. If the indication information is channel quality information, such as RSSI, AP3 can obtain the result. If the indication information is unselected indication information, AP3 determines that it is not selected. In addition, the beamforming report frame also includes the MIMO control field and beamforming report field of AP1, the MIMO control field and beamforming report field of AP2, and the MIMO control field of AP3. Optionally, the beamforming report frame can also be as follows. Fig.17 As shown, the identification information of the AP can be carried in the MIMO control field, but not in the beamforming report field and the selection information field. The frame structure is the same as Fig.12 Similar, related descriptions can be found in Fig.12 The content is not repeated here.

[0199] For 2), the channel measurement report frames of each AP may be independent of each other. For example, the channel measurement report frame of AP1 includes the identification information and channel status information of AP1, but does not include the information of other APs.

[0200] For example, the beamforming report of AP3 may include a selection information field. The function of the selection information field is as described above and will not be repeated here. The frame structure of the beamforming report frame may be as follows: Fig.18 As shown, refer to Fig.18 The field may also include other fields such as the MIMO control field of AP3.

[0201] It should be noted that step 304 and step 305 can be executed simultaneously or sequentially, and the execution order is not limited.

[0202] Scene 3

[0203] Combination Figure 3 ,like Fig.19 FIG. 1 is a flow chart of a channel detection method in an embodiment of the present application. Fig.19 middle:

[0204] Steps 401 to 404 may refer to the steps in scenario 1 or scenario 2, and are not described in detail here.

[0205] Step 405: The target AP and the STA receive the first data sent by the master AP.

[0206] Optionally, in the present application, the master AP may be one of the m target APs, or may not be a target AP. For example, the master AP may be Figure 3 AP1 in.

[0207] Specifically, the master AP shares the first data with the target AP, and at the same time, the STA can also receive the first data shared by the master AP. If the STA successfully receives the first data, the process proceeds to step 406. If the STA fails to receive the first data, the process proceeds to step 407.

[0208] Optionally, in step 406, the STA sends a reception success response frame.

[0209] Specifically, in the present application, the STA may send a successful reception response frame to the main AP, or to the main AP and other target APs, to inform the main AP, or the main AP and other target APs that the first data is successfully received. The main AP, or the main AP and other target APs may delete the cached first data, thereby reducing device pressure.

[0210] Step 407: The STA sends a retransmission request frame to p retransmission APs among the m target APs, where the retransmission request frame is used to instruct the p retransmission APs to retransmit the first data.

[0211] Specifically, in the present application, if the STA fails to receive the first data, the STA may select p retransmission APs from the m target APs and send a retransmission request frame to the p retransmission APs, where the retransmission request frame is used to instruct the retransmission APs to retransmit the first data to the STA.

[0212] Optionally, in this application, the STA may select a primary AP (eg Figure 3 The STA sends a retransmission request frame to the primary AP to instruct the primary AP to retransmit the first data.

[0213] Optionally, in the present application, the STA may select a target AP other than the primary AP or the AP that previously sent the first data as a retransmission AP. Optionally, the number of retransmission APs may be greater than or equal to 1 and less than or equal to m.

[0214] Optionally, in the present application, the STA may select p retransmission APs according to a preset rule. Optionally, the preset rule may be: selecting p APs with the best channel status from m target APs, etc., which is not limited in the present application.

[0215] Optionally, in the present application, the retransmission request frame includes but is not limited to: a retransmission mode field, a retransmission AP information field, and / or a sending address indication field. Among them, the retransmission mode field can be used to indicate whether the retransmitting AP adopts joint transmission to retransmit the first data. Optionally, setting 1 in the retransmission mode field can indicate joint transmission, and setting 0 can indicate non-joint transmission. Optionally, the retransmission request frame may also include a sending address indication field, which is used to indicate the address information carried in the first data sent by the retransmitting AP. Optionally, the sending address indication field is the address information of the AP that sent the first data last time. Optionally, the address information can be MAC address information.

[0216] Optionally, the retransmission request frame may also include a destination address field (or may be referred to as a receiving address field (RA)) and a retransmission AP information field, wherein the destination address field is a broadcast address or address information of a retransmission AP; the retransmission AP information field may include identification information of the retransmission AP. Optionally, the identification information may be information such as a MAC address or AID of the retransmission AP.

[0217] Optionally, if the retransmission request frame is sent in a broadcasting mode, when the retransmission AP information field includes identification information of multiple APs, the retransmission request frame may not include the retransmission mode field. The AP whose local identification information successfully matches the identification information carried in the retransmission AP information field may be confirmed as the retransmission AP and jointly transmit the first data with other retransmission APs.

[0218] Optionally, if the retransmission request frame is sent in unicast mode and the STA selects only one retransmission AP, the retransmission request frame may not include the retransmission AP information field and / or the retransmission mode field. The AP that receives the retransmission request frame may be identified as the retransmission AP and retransmit the first data using non-joint transmission. Fig. 20 The frame structure diagram of the retransmission request frame is shown in FIG. Fig. 20 The retransmission request frame may also include a transmitting address field (TA), a frame control field, a duration field, a frame check sequence (FCS), etc.

[0219] Step 408: p retransmitting APs send first data.

[0220] Specifically, in the present application, the AP that receives the retransmission request frame resends the first data.

[0221] Optionally, if the AP receiving the retransmission request frame is the AP that sent the first data last time, such as AP1, and the retransmission request frame indicates that non-joint transmission is adopted, then the master AP resends the first data to the STA after receiving the retransmission request frame.

[0222] Optionally, if the AP that receives the retransmission request frame is not the AP that sent the first data last time, for example, AP2. AP2 identifies whether the retransmission AP information field in the retransmission request frame includes indication information of multiple APs and / or joint transmission indication. If included, AP2 retransmits the first data with other retransmitting APs. If not included, AP2 retransmits the first data to the STA. Optionally, if the retransmission request frame received by AP2 also includes a sending address indication field, and the sending address indication field includes the address information of the AP that sent the first data last time, then the first data retransmitted by AP2 includes the address information of the AP that sent the first data last time, for example, the address information of AP1.

[0223] Step 409: The STA decodes the received first data to obtain the decoded first data.

[0224] Specifically, the STA receives the first data sent by the retransmitting AP, and decodes the first data to obtain the decoded first data.

[0225] Optionally, if the address information carried in the first data re-received by the STA is the same as the address information carried by the first data received last time, the STA may perform joint soft decoding on the first data received this time and last time, thereby improving the decoding accuracy. Optionally, the STA may perform joint soft decoding on the first data with the same address information received multiple times, that is, the STA may instruct the retransmission AP to retransmit the first data after each failure to receive the first data, and the content of the sending address indication field carried in the retransmission request frame is consistent, which is used to indicate that the first data retransmitted by the retransmission AP each time includes the same address information.

[0226] Optionally, in the present application, in order to implement the above-mentioned collaborative transmission mode, the STA and / or AP may send a dynamic AP selection indication to indicate that the STA dynamically selects the retransmission AP when retransmitting data. Optionally, the dynamic AP selection indication may be carried in the physical preamble of the physical layer protocol data unit. Optionally, the physical preamble may be the physical preamble of the NDP sent by the AP, or the physical preamble of the first data, which is not limited in the present application. A structural diagram of a physical layer protocol data unit is shown in FIG. Fig.21As shown, the physical preamble may include at least one signaling field (SIG), which may also be called a next generation signaling field, and the signaling field may include an AP collaboration field. In an example, the function corresponding to the value of the AP collaboration field may be as shown in Table 4.

[0227] Table 4

[0228]

[0229] It should be noted that the values ​​corresponding to each field in each table in this application can be set according to actual needs, and this application does not limit it.

[0230] Optionally, the cooperative transmission method in scenario 3 can also be applied to Fig. 22 In the application scenario shown, of course, the cooperative transmission method in scenario three can also be applied to other scenarios. Fig. 22 This is for illustrative purposes only. Fig. 22 In the example, AP1 and AP3 perform cooperative transmission to STA1, and AP2 and AP3 perform cooperative transmission to STA2. Specifically, when AP1 sends second data to STA1, the second data is shared with AP3. When AP2 sends third data to STA2, the third data is shared with AP3.

[0231] Optionally, similar to scenario 3, if STA1 fails to receive the second data sent by AP1, STA1 may select AP1, or AP3, or AP1 and AP3 as the retransmission AP, and send a retransmission request to the retransmission AP, instructing the retransmission AP to retransmit the second data. The retransmission method can refer to scenario 3, which is not described here. For STA2, AP2, or AP3, or AP2 and AP3 can also be selected as the retransmission AP. The specific details can refer to scenario 3, which is not described here.

[0232] Optional, in Fig. 22 In the transmission architecture shown, AP1 and AP2 can send data at the same time or at different times. Optionally, if AP1 and AP2 send data at different times, AP3 can cache the second data and the third data respectively, and if AP3 is selected as the retransmission AP by STA1, AP3 retransmits the second data to STA1. If AP3 is selected as the retransmission AP by STA2, AP3 retransmits the third data to STA2.

[0233] Optionally, if AP1 and AP2 send data at the same time, AP3 can cache the second data and the third data respectively, or AP3 can also merge the second data and the third data. That is, if AP3 is selected as the retransmission AP by STA1, the data resent by AP3 to STA1 is the merged data. It should be noted that if it is the merged data, STA1 and / or STA2 need to decode the merged data in an XOR manner and also obtain the second data or the third data.

[0234] The above mainly introduces the solution provided by the embodiment of the present invention from the perspective of interaction between various network elements. It can be understood that in order to implement the above functions, STA and AP include hardware structures and / or software modules corresponding to the execution of various functions. 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 in this document, the embodiments of the present invention can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in hardware or in a computer software-driven hardware manner 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 exceed the scope of this application.

[0235] The embodiment of the present invention can divide the functional modules of AP and STA according to the above method example. 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 invention is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0236] In the case of dividing each functional module into corresponding functional modules, Fig.23 A possible structural diagram of the communication device 100 on the STA side involved in the above embodiment is shown, such as Fig.23As shown, the device 100 may include: a transceiver module 11 and an acquisition module 12. The transceiver module 11 may be used to support the STA to execute the step of "receiving channel detection frames sent by n APs", for example, it may support the STA to execute steps 102, 202, 302, and 402 in the above embodiment. Alternatively, the transceiver module 11 may also be used to support the STA to execute the step of "sending a channel measurement report frame", for example, it may support the STA to execute steps 104, 204, 304, and 404 in the above embodiment. Alternatively, the transceiver module 11 may also be used to support the STA to execute the step of "sending an indication frame", for example, it may support the STA to execute steps 205, 305, and 405 in the above embodiment. Alternatively, the transceiver module 11 may also be used to support the STA to execute the step of "sending or receiving a feedback type indication". Alternatively, the transceiver module 11 may also be used to support the STA to execute the step of "receiving the first data sent by the master AP", for example, it may support the STA to execute step 405 in the above embodiment. Alternatively, the transceiver module 11 may also be used to support the STA to execute the step of "if the first data reception fails, then send a retransmission request frame to p retransmission APs among the m target APs", for example, the STA may be supported to execute step 407 in the above embodiment. Alternatively, the transceiver module 11 may also be used to support the STA to execute the step of "receiving the first data retransmitted by the retransmission AP", for example, the STA may be supported to execute step 409 in the above embodiment. The acquisition module 12 may be used to support the STA to execute the step of "performing channel detection based on the channel detection frame to obtain the channel state information of each AP", for example, the STA may be supported to execute steps 102, 202, 302, and 402 in the above embodiment.

[0237] Optional, such as Fig.23 As shown, the device 100 may also include a decoding module 13, which can be used to support the STA to execute the step of "performing joint soft decoding based on the first data retransmitted by the retransmitting AP and the first data sent by the main AP to obtain the decoded first data". For example, it can support the STA to execute step 408 in the above embodiment.

[0238] 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.

[0239] In another example, Fig.24A schematic block diagram of another STA-side communication device 200 of an embodiment of the present application is shown. The device 200 of the embodiment of the present application may be the STA in the above method embodiment, and the device 200 may be used to perform part or all of the functions of the STA in the above method embodiment. The device 200 may include: a processor 21, a baseband circuit 23, a frequency circuit 24, and an antenna 25. Optionally, the device 200 may also include a memory 22. The various components of the device 200 are coupled together through a bus 26, wherein the bus 26 includes a power bus, a control bus, and a status signal bus in addition to a data bus. However, for the sake of clarity, various buses are labeled as bus systems 26 in the figure.

[0240] The processor 21 can be used to control the STA, to execute the processing performed by the STA in the above-mentioned embodiments, to execute the processing procedures involving the STA in the above-mentioned method embodiments and / or other processes for the technology described in this application, and to run an operating system, be responsible for managing the bus, and execute programs or instructions stored in the memory.

[0241] The baseband circuit 23, the radio frequency circuit 24 and the antenna 25 can be used to support the sending and receiving of information between the STA and the AP or the station involved in the above embodiment, so as to support wireless communication between the STA and other nodes. In one example, the signaling or data generated by the baseband circuit 23 after encoding and encapsulating according to the protocol is processed by the radio frequency circuit for analog conversion, filtering, amplification and up-conversion, and then sent to the AP via the antenna 25. In another example, the channel detection frame sent by the AP is received via the antenna 25, filtered, amplified, down-converted and digitized by the radio frequency circuit 24, and then decoded by the baseband circuit 23, decapsulated according to the protocol, and processed by the processor 21 to restore the service data and signaling information sent by the station. It can be understood that the baseband circuit 23, the radio frequency circuit 24 and the antenna 25 can also be used to support the STA to communicate with other network entities, for example, to support the STA to communicate with the network element on the core network side.

[0242] The memory 22 may be used to store the program code and data of the STA, and it is easy for those skilled in the art to understand that the memory 22 or any part thereof may be located outside the device 200. For example, the memory 22 may include a transmission line and / or a computer product separated from the wireless node, and these media may be accessed by the processor 21 through the bus interface 26. Alternatively, the memory 22 or any part thereof may be integrated into the processor 21, for example, it may be a cache and / or a general register.

[0243] Understandably, Fig.24Only a simplified design of STA is shown. For example, in practical applications, STA may include any number of transmitters, receivers, processors, memories, etc., and all STAs that can implement the present invention are within the protection scope of the present invention.

[0244] like Fig.25 FIG. 3 is a schematic block diagram of an access point side device 300 according to an embodiment of the present application. Fig.25 The device 300 shown may correspond to the device on the AP side in the above method embodiment, and may have any function of the AP in the method. Optionally, the device 300 in the embodiment of the present application may be an AP or a chip in the AP. The device 300 may include a transceiver module 31 and a processing module 32. Optionally, the device 300 may also include a storage module 33. The storage module 33 may be used to cache all or part of the first data.

[0245] The transceiver module 31 can be understood to include a receiving module and a sending module. The receiving module can be used to receive the signaling or data sent by the STA in step 104, step 204, step 304, step 404, step 405, and step 406 of the aforementioned method embodiment. The sending module can be used to send the signaling or data in step 101, step 201, step 301, step 401, step 405, and step 408 of the aforementioned embodiment.

[0246] The processing module 32 may be used to execute the relevant steps of determining whether to be selected by the STA to participate in the cooperative transmission based on the feedback information of the channel state information in the aforementioned method embodiment.

[0247] It should be understood that the device 300 according to the embodiment of the present application may correspond to the AP in the various methods of the aforementioned embodiments, and the above-mentioned and other management operations and / or functions of each module in the device 300 are respectively for implementing the corresponding steps of the aforementioned methods. For the sake of brevity, they will not be repeated here.

[0248] In another example, Fig.26 A schematic block diagram of another communication device 400 on the AP side of an embodiment of the present application is shown. The device 400 of the embodiment of the present application may be the AP in the above method embodiment, and the device 400 may be used to perform part or all of the functions of the AP in the above method embodiment. The device 400 may include: a processor 41, a baseband circuit 43, a radio frequency circuit 44 and an antenna 45. Optionally, the device 400 may also include a memory 42. The various components of the device 400 are coupled together through a bus 46, wherein the bus system 46 includes a power bus, a control bus and a status signal bus in addition to a data bus. However, for the sake of clarity, various buses are labeled as bus systems 46 in the figure.

[0249] The processor 41 can be used to control the AP, to execute the processing performed by the AP in the above-mentioned embodiments, to execute the processing procedures involving the AP in the above-mentioned method embodiments and / or other processes used for the technology described in this application, and to run an operating system, be responsible for managing the bus, and execute programs or instructions stored in the memory.

[0250] The baseband circuit 43, the radio frequency circuit 44 and the antenna 45 can be used to support the AP and the STA or AP involved in the above embodiments to send and receive information, so as to support wireless communication between the AP and other nodes. In one example, the signaling or data sent by the STA, such as the channel measurement report frame, is received via the antenna 45, and is filtered, amplified, down-converted and digitized by the radio frequency circuit 44, and then decoded by the baseband circuit 43, decapsulated data according to the protocol, and processed by the processor 41 to restore the service data and signaling information sent by the station; in another example, the collaborative response message sent by the AP can be processed by the processor 41, encapsulated according to the protocol, encoded and other baseband processing by the baseband circuit 43, and further processed by the radio frequency circuit 44 to analog conversion, filtering, amplification and up-conversion, and then sent to the STA via the antenna 45. It can be understood that the baseband circuit 43, the radio frequency circuit 44 and the antenna 45 can also be used to support the AP to communicate with other network entities, for example, to support the AP to communicate with the network element on the core network side.

[0251] The memory 42 can be used to store the program code and data of the AP. The memory 42 can be Fig.25 The storage module 33 in. Fig.26 The memory 42 is shown as being separated from the processor 41, however, it is readily apparent to those skilled in the art that the memory 42 or any portion thereof may be located outside the device 400. For example, the memory 42 may include a transmission line and / or a computer product separated from a wireless node, and these media may be accessed by the processor 41 through the bus interface 46. Alternatively, the memory 42 or any portion thereof may be integrated into the processor 41, for example, may be a cache and / or a general register.

[0252] Understandably, Fig.26 Only a simplified design of the AP is shown. For example, in practical applications, the AP may include any number of transmitters, receivers, processors, memories, etc., and all APs that can implement the present invention are within the protection scope of the present invention.

[0253] The embodiment of the present application also provides a computer-readable storage medium, in which instructions are stored, and the instructions can be executed by one or more processors on the processing circuit. When the instructions are run on a computer, the computer executes the methods described in the above aspects. Optionally, the computer storage medium is a non-volatile readable storage medium.

[0254] An embodiment of the present application also provides a chip system, which includes a processor for supporting a STA or an AP to implement the functions involved in the above embodiments, such as generating or processing the data and / or information involved in the above methods.

[0255] In a possible design, the chip system may also include a memory, which is used to store program instructions and data necessary for the STA or AP. The chip system may be composed of a chip, or may include a chip and other discrete devices, and the processor is used to execute the program instructions so that the communication device installed with the chip system implements the methods and functions of the AP or STA involved in any of the above embodiments. Optionally, the memory may be located outside the processor as an external storage medium, or may be located inside the processor as an internal storage medium of the processor.

[0256] The embodiment of the present application also provides a processor, which is coupled with a memory and is used to execute the method and function related to STA in any of the above embodiments.

[0257] The embodiment of the present application also provides a processor, which is coupled with a memory and is used to execute the method and function related to the AP in any of the above embodiments.

[0258] An embodiment of the present application also provides a chip, including a processing circuit and an input-output circuit, wherein the input-output circuit is used to input signaling or data to the processing circuit, and is also used to output signaling or data generated by the processing circuit, and the processing circuit is used to implement signaling or data processing, so that a communication device equipped with the chip can implement the methods and functions involving STA in any of the above embodiments.

[0259] An embodiment of the present application also provides a chip, including a processing circuit and an input-output circuit, wherein the input-output circuit is used to input signaling or data to the processing circuit, and is also used to output signaling or data generated by the processing circuit, and the processing circuit is used to implement signaling or data processing, so that a communication device equipped with the chip can implement the methods and functions involving AP in any of the above embodiments.

[0260] The embodiment of the present application also provides a computer program product including instructions, which, when executed on a computer, enables the computer to execute the method and function involving STA in any of the above embodiments.

[0261] The embodiment of the present application also provides a computer program product including instructions, which, when executed on a computer, enables the computer to execute the method and function involving AP in any of the above embodiments.

[0262] An embodiment of the present application also provides a wireless communication system, which includes at least one STA and at least one AP involved in the above embodiment.

[0263] The steps of the method or algorithm described in conjunction with the disclosed content of the embodiments of the present invention may be implemented in hardware or by executing software instructions by a processor. The software instructions may be composed of corresponding software modules, which may be stored in a random access memory (RAM), a flash memory, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a register, a hard disk, a mobile hard disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium may also be a component of the processor. The processor and the storage medium may be located in an ASIC. In addition, the ASIC may be located in an AP. Of course, the processor and the storage medium may also be present in the AP as discrete components.

[0264] Those skilled in the art should be aware that in one or more of the above examples, the functions described in the embodiments of the present invention can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any media that facilitates the transmission of computer programs from one place to another. Storage media can be any available media that can be accessed by general or special-purpose computers.

[0265] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A channel detection method, characterized in that: include: The station STA receives a null data packet declaration NDPA frame sent by one AP among n APs or the n APs, where the NDPA frame is used to instruct the STA to perform channel detection; The STA receives the channel detection frames sent by the n APs, where n is an integer greater than 1; The STA performs channel detection based on the channel detection frame to obtain channel state information of each AP; The STA sends a channel measurement report frame, which includes channel state information of m target APs among the n APs and identifiers of the m target APs. The channel measurement report frame is also used to indicate that the m target APs are selected to participate in collaborative transmission, where m is an integer greater than 1 and less than or equal to n.

2. The method according to claim 1, characterized in that The method further comprises: The STA sends indication information, where the indication information is used to indicate that (nm) non-target APs are not selected to participate in the collaborative transmission.

3. The method according to claim 2, characterized in that The indication information includes the channel quality information of the (nm) non-target APs and the identifiers of the (nm) non-target APs; or, The indication information includes unselected indication information and identifiers of the (nm) non-target APs, the unselected indication information is used to indicate that the (nm) non-target APs are not selected, and the channel quality information is used to indicate the channel quality of the channel between the non-target AP and the STA.

4. The method according to any one of claims 1 to 3, characterized in that Before sending the channel measurement report frame, the method further includes: The STA sends or receives a feedback type indication, where the feedback type indication is used to indicate a type of channel state information fed back by the STA, where the type of channel state information fed back by the STA includes: selective feedback and non-selective feedback; The selective feedback indicates that the STA feeds back the channel state information of some of the n APs, and the non-selective feedback indicates that the STA feeds back the channel state information of each of the n APs.

5. The method according to any one of claims 1 to 3, characterized in that The channel measurement report frame includes: a multiple-input multiple-output control field, and a feedback type field of the multiple-input multiple-output control field is a reserved value, which is used to indicate that the type of the STA feedback channel state information is selective feedback.

6. The method according to claim 1, characterized in that The method further comprises: The STA receives first data sent by the master AP, wherein the first data is data shared among the m target APs, and the master AP is included in the m target APs; If the STA fails to receive the first data, a retransmission request frame is sent to p retransmission APs among the m target APs, where the retransmission request frame is used to instruct the p retransmission APs to resend the first data, where p is an integer greater than or equal to 1 and less than or equal to m.

7. The method according to claim 6, characterized in that in, The retransmission request frame includes at least one of the following: a destination address field, a retransmission AP information field, a retransmission mode field, and a transmission address indication field; Wherein, the destination address field is a broadcast address or the address of the retransmitting AP; The retransmission AP information field includes identification information of the retransmission AP; The retransmission mode field is used to indicate whether to retransmit the first data using joint transmission; The sending address indication field is used to indicate the address information of the primary AP carried by the first data.

8. The method according to any one of claims 6 or 7, characterized in that: If the p retransmitting APs are not the primary AP, the method further includes: receiving first data retransmitted by the retransmitting AP, wherein the first data includes address information of the master AP; Based on the first data retransmitted by the retransmitting AP and the first data sent by the main AP, joint soft decoding is performed to obtain the first data after joint soft decoding.

9. A channel detection method, characterized in that: include: The access point AP sends a null data packet declaration NDPA frame to the station STA, where the NDPA frame is used to instruct the STA to perform channel detection; The AP sends a channel detection frame, where the channel detection frame is used by the STA to perform channel detection to obtain channel state information; The AP receives feedback information sent by the STA; Based on the feedback information, the AP determines whether it is selected by the STA to participate in the collaborative transmission; If the feedback information is a channel measurement report frame, determining whether the AP is selected by the STA to participate in cooperative transmission based on the feedback information includes: Receive the channel measurement report frame fed back by the STA, and identify whether the channel measurement report frame includes the identification information of the AP and the channel state information of the AP, wherein the channel measurement report frame includes the channel state information of m target APs and the identifications of the m target APs; If the identification information and the channel state information of the AP are identified, it is determined that the AP is selected to participate in the collaborative transmission.

10. The method according to claim 9, characterized in that If the feedback information is indication information, determining whether the AP is selected by the STA to participate in the collaborative transmission based on the feedback information includes: The AP receives the indication information sent by the STA, where the indication information is used to indicate that the AP is not selected to participate in the collaborative transmission; The AP determines, based on the indication information, that the AP is not selected to participate in the collaborative transmission.

11. The method according to claim 10, characterized in that The indication information includes the channel quality information of the AP and the identifier of the AP; or The indication information includes unselected indication information and an identifier of the AP, wherein the unselected indication information is used to indicate that the AP is not selected; The channel quality information is used to indicate the channel quality of the channel between the AP and the STA.

12. The method according to any one of claims 9 to 11, characterized in that: Before the STA feeds back the channel measurement report frame, the method further includes: The AP sends or receives a feedback type indication, where the feedback type indication is used to indicate a type of channel state information fed back by the STA, where the type of channel state information fed back by the STA includes: selective feedback and non-selective feedback; The selective feedback means that the STA feeds back the channel state information of some APs among the n APs, and the non-selective feedback means that the STA feeds back the channel state information of each AP among the n APs.

13. The method according to claim 9, characterized in that The method further comprises: The AP receives first data sent by the main AP to the AP and the STA; The AP receives a retransmission request frame sent by the STA, wherein the retransmission request frame is sent by the STA to the AP after failing to receive the first data, and the retransmission request frame is used to instruct the AP to resend the first data; Send the first data to the STA.

14. The method according to claim 13, characterized in that in, The retransmission request frame includes a sending address indication field for indicating address information of a primary AP that sends the first data. The method further includes: The AP sends first data including address information of the master AP to the STA.

15. A communication device applied to a station STA, characterized in that: include: A transceiver module is used to receive an empty data packet declaration NDPA frame sent by one or all of the n APs, and the NDPA frame is used to instruct the STA to perform channel detection The transceiver module is further used to receive channel detection frames sent by n APs, where n is an integer greater than 1; An acquisition module, configured to perform channel detection based on the channel detection frame to obtain channel state information of each AP; The transceiver module is also used to send a channel measurement report frame, which includes channel state information of m target APs among the n APs and identifiers of the m target APs. The channel measurement report frame is also used to indicate that the m target APs are selected to participate in collaborative transmission, where m is an integer greater than 1 and less than or equal to n.

16. The communication device according to claim 15, characterized in that: The transceiver module is further used to send indication information, where the indication information is used to indicate that (nm) non-target APs are not selected to participate in the collaborative transmission.

17. The communication device according to claim 16, characterized in that: The indication information includes the channel quality information of the (nm) non-target APs and the identifiers of the (nm) non-target APs; or, The indication information includes unselected indication information and identifiers of the (nm) non-target APs, wherein the unselected indication information is used to indicate that the (nm) non-target APs are not selected; The channel quality information is used to indicate the channel quality of the channel between the non-target AP and the STA.

18. The communication device according to any one of claims 15 to 17, characterized in that: The transceiver module is also used for: Sending or receiving a feedback type indication, where the feedback type indication is used to indicate a type of the STA feedback channel state information, where the type of the STA feedback channel state information includes: selective feedback and non-selective feedback; The selective feedback indicates that the STA feeds back the channel state information of some of the n APs, and the non-selective feedback indicates that the STA feeds back the channel state information of each of the n APs.

19. The communication device according to any one of claims 15 to 17, characterized in that: The channel measurement report frame includes: a multiple-input multiple-output control field, and a feedback type field of the multiple-input multiple-output control field is a reserved value, which is used to indicate that the type of the STA feedback channel state information is selective feedback.

20. The communication device according to claim 15 or 16, characterized in that: The transceiver module is also used for: receiving first data sent by a master AP, wherein the first data is data shared among the m target APs, and the master AP is included in the m target APs; If the STA fails to receive the first data, a retransmission request frame is sent to p retransmission APs among the m target APs, where the retransmission request frame is used to instruct the p retransmission APs to resend the first data, where p is an integer greater than or equal to 1 and less than or equal to m.

21. The communication device according to claim 20, characterized in that: in, The retransmission request frame includes a destination address field, a retransmission AP information field, a retransmission mode field, and a sending address indication field; Wherein, the destination address field is a broadcast address or the address of the retransmitting AP; The retransmission AP information field includes identification information of the retransmission AP; The retransmission mode field is used to indicate whether to retransmit the first data using joint transmission; The sending address indication field is used to indicate that the first data carries the address information of the primary AP.

22. The communication device according to claim 20, characterized in that If the p retransmitting APs are not the main AP, the transceiver module is further used for: receiving first data retransmitted by the retransmitting AP, wherein the first data includes address information of the master AP; Correspondingly, the STA further includes a decoding module, which is used to perform joint soft decoding based on the first data retransmitted by the retransmitting AP and the first data sent by the main AP, and obtain the first data after the joint soft decoding.

23. A communication device applied to an access point AP, characterized in that: include: A transceiver module, used to send a null data packet declaration NDPA frame to a station STA, wherein the NDPA frame is used to instruct the STA to perform channel detection; A transceiver module, used to send a channel detection frame, where the channel detection frame is used by the STA to perform channel detection based on the channel detection frame and obtain channel state information; The transceiver module is further used to receive feedback information sent by the STA; A processing module, configured to determine whether the AP is selected by the STA to participate in cooperative transmission based on the feedback information; If the feedback information is a channel measurement report frame, The transceiver module is also used to receive the channel measurement report frame fed back by the STA; The processing module is further used to identify whether the channel measurement report frame includes the identification information of the AP and the channel state information of the AP, and the channel measurement report frame includes the channel state information of m target APs and the identifications of the m target APs; If the identification information of the AP and the channel state information of the AP are identified, the processing module determines that the AP is selected to participate in the cooperative transmission.

24. The communication device according to claim 23, characterized in that If the feedback information is indication information; The transceiver module is further used to receive the indication information sent by the STA, where the indication information is used to indicate that the AP is not selected to participate in the collaborative transmission; The processing module is further configured to determine, based on the indication information, that the AP is not selected to participate in the collaborative transmission.

25. The communication device according to claim 24, characterized in that The indication information includes the channel quality information of the AP and the identifier of the AP; or The indication information includes unselected indication information and an identifier of the AP, and the unselected indication information is used to indicate that the AP is not selected.

26. The communication device according to any one of claims 23 to 25, characterized in that: The transceiver module is also used for: Sending or receiving a feedback type indication, where the feedback type indication is used to indicate a type of the STA feedback channel state information, where the type of the STA feedback channel state information includes: selective feedback and non-selective feedback; The selective feedback means that the STA feeds back the channel state information of some APs among the n APs, and the non-selective feedback means that the STA feeds back the channel state information of each AP among the n APs.

27. The communication device according to claim 23, characterized in that The transceiver module is also used for: Receiving first data sent by a master AP to the AP and the STA; receiving a retransmission request frame sent by the STA, wherein the retransmission request frame is sent by the STA to the AP after failing to receive the first data, and the retransmission request frame is used to instruct the AP to resend the first data; Send the first data to the STA.

28. The communication device according to claim 27, characterized in that in, The retransmission request frame includes a sending address indication field for indicating address information of a primary AP that sends the first data, and the transceiver module is further used for: First data including address information of the master AP is sent to the STA.

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