CN113595602A

CN113595602A - Method of channel sounding, communication device, and computer-readable storage medium

Info

Publication number: CN113595602A
Application number: CN202110332135.8A
Authority: CN
Inventors: 于健; 郭宇宸
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-09-22
Filing date: 2017-09-22
Publication date: 2021-11-02
Anticipated expiration: 2037-09-22
Also published as: CN109547072B; CN109547072A; CN113595602B

Abstract

A method, a communication device, and a computer-readable storage medium for channel sounding are provided. The method comprises the following steps: at least one first communication device in the first communication device group transmits an NDPA frame; each first communication device in the first communication device group sends an NDP to a second communication device in the second communication device group, wherein the NDP is used for indicating the second communication device to probe channel information with at least one first communication device; at least one first communication device in the first communication device group sends a trigger frame to at least one second communication device in the second communication device group, wherein the trigger frame is used for triggering the at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device; at least one first communication device in the first communication device group receives the channel information fed back by the at least one second communication device. The method greatly improves the feedback efficiency of the channel information.

Description

Method of channel sounding, communication device, and computer-readable storage medium

Technical Field

The present application relates to communication technologies, and in particular, to a method, a communication device, and a computer-readable storage medium for channel sounding.

Background

Currently, in Wireless systems such as a Wireless Local Area Network (WLAN), an Access Point (AP) and a Station (STA) need to acquire channel state information in advance to perform functions such as Beamforming (BF), rate control, and resource allocation, so as to improve communication efficiency between the AP and the STA. Referring to fig. 1, taking an 802.11ac channel Sounding (Sounding) process as an example, the specific process includes: 1) an AP sends a Null Data Packet Announcement (NDPA) frame to inform a target STA needing channel detection of the current channel detection and parameters needed by the channel detection; 2) after the AP separates a Short Inter-frame Space (SIFS), the AP sends a Null Data Packet (NDP) to the aforementioned destination STA; 3) after the destination STA identifies itself as an STA requiring Channel sounding through the NDPA frame and obtains a Channel sounding indication parameter, Channel estimation is performed through the monitored NDP, and then Channel State Information (CSI) between the destination STA and the AP is fed back to the AP through a Beamforming Report (BFR). It should be noted that, in 802.11ac, the default destination STA that feeds back BFR to the AP first is the first STA indicated by the field of each station in the NDPA frame, and for the BFRs of other STAs, the AP needs to ask for the BFR through a beam forming Report Poll (BF Report Poll, abbreviated as BRP) frame.

In order to improve the applicability of channel Sounding based on 802.11ac, a channel Sounding process is introduced in a WLAN for multiple APs and multiple STAs, which may be applicable to a multi-cell joint transmission scenario, where the channel Sounding process is shown in fig. 2: the NDPA frame and NDP are sent first by AP1, then AP2 sends NDP, then STA11 starts feeding back BFR to AP1, after which AP1 continues to ask STA12 for BFR through BRP frames. After the AP1 finishes requesting channel state information from its associated STAs, the AP1 sends a Start Poll (SP) frame to the AP2 to inform the AP2 to continue requesting channel state information from STAs associated with the AP 2.

However, in the above-mentioned process in which the plurality of APs perform channel sounding with the plurality of STAs, the CSI feedback efficiency is low.

Disclosure of Invention

The application provides a channel sounding method, a communication device and a computer readable storage medium, which are used for solving the technical problem that in the prior art, the feedback efficiency of CSI is low in the process of carrying out channel sounding on a plurality of APs and a plurality of STAs.

In a first aspect, an embodiment of the present application provides a channel sounding method, which is applied to a communication system including a first communication device group and a second communication device group participating in channel sounding, where the first communication device group includes at least one first communication device, and the second communication device group includes at least one second communication device; the method comprises the following steps:

at least one first communication device in the first communication device group sends a Null Data Packet Announcement (NDPA) frame, wherein the NDPA frame is used for indicating the first communication device group and the second communication device group which participate in channel detection, and the channel detection comprises channel information for detecting a channel between the at least one first communication device and the at least one second communication device;

each first communication device in the first communication device group sends a Null Data Packet (NDP) to a second communication device in the second communication device group, wherein the NDP is used for indicating the second communication device to probe channel information with at least one first communication device;

at least one first communication device in the first communication device group sends a trigger frame to at least one second communication device in the second communication device group, wherein the trigger frame is used for triggering the at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

at least one first communication device in the first communication device group receives the channel information fed back by the at least one second communication device.

In the method provided by the first aspect, a trigger frame is sent to at least one second communication device by at least one first communication device in a first communication device group, where the trigger frame is used to ask for channel information between the at least one second communication device and the at least one first communication device from the at least one second communication device, so that each second communication device can not only feed back the channel information to the first communication device that sent the trigger frame, but also feed back the channel information to other first communication devices in the first communication device group, that is, in this embodiment, the second communication device feeds back the channel information to one or more first communication devices under the indication of the trigger frame, and the method of this embodiment greatly improves the feedback efficiency of the channel information.

In a possible design, the sending, by at least one first communication device in the first communication device group, an NDPA frame specifically includes:

a master communication device in the first communication device group sends an NDPA frame; the NDPA frame is further configured to indicate an identifier permutation order of the first communication devices in the first communication device group and a channel sounding indication parameter required when the at least one second communication device acquires channel information.

In a possible design, the receiving, by at least one first communication device in the first communication device group, channel information fed back by at least one second communication device specifically includes:

at least one first communication device in the first communication device group receives channel information fed back by at least one second communication device according to the identification arrangement sequence of the first communication devices in the first communication device group.

The method provided by the possible design can enable the second communication equipment to feed back the channel information according to the identifier arrangement sequence when feeding back the channel information, thereby being beneficial to the second communication equipment to acquire the channel information in time and greatly reducing the processing complexity of feeding back the channel information between one second communication equipment and a plurality of first communication equipment at the same time.

In one possible design, the method further includes:

at least one first communication device in the first communication device group sends a transmission opportunity transfer frame to the next first communication device according to the identification arrangement sequence of the first communication devices in the first communication device group; the transmission opportunity transfer frame is used for instructing the next first communication device to send the trigger frame to the at least one second communication device according to the identifier arranging sequence.

In one possible design, the method further includes:

and if the next first communication device is the last first communication device in the identifier arrangement sequence, the next first communication device sends a transmission opportunity returning frame to the main communication devices in the first communication device group, and the transmission opportunity returning frame is used for indicating the first communication devices in the first communication device group to successfully receive the required channel information to the main communication devices.

According to the method provided by the possible design, after a certain first communication device in the first communication device group sends a trigger frame, the first communication device sends a transmission opportunity transfer frame to the next first communication device according to an identification list field set by first communication in an NDPA frame, so that the opportunity of sending the trigger frame is transferred to the next first communication device, and therefore other first communication devices can obtain the opportunity of asking for channel information from at least one second communication device, the integrity of channel information feedback is improved, and the situation that channel information is not completely obtained is avoided.

In one possible design, the method further includes:

if the next first communication device sends the trigger frame meeting the preset condition, the next first communication device sends a failure frame to the main communication device, so as to inform the main communication device that the next first communication device cannot successfully receive the channel information fed back by the at least one second communication device;

wherein the preset conditions include: and the sending times of the next first communication equipment sending the trigger frame reach at least one of a first preset threshold value and the total sending time of the next first communication equipment sending the trigger frame reach a second preset threshold value.

In one possible design, the method further includes:

and the main communication device or the next first communication device sends the transmission opportunity transfer frame to another first communication device which is positioned behind the next first communication device and adjacent to the next first communication device according to the identification arrangement sequence.

The method provided by this possible design, when one first communication device in the first communication device group sends a transmission opportunity transfer frame to a next first communication device, the next first communication device sends a trigger frame to at least one second communication device according to the transmission opportunity transfer frame, and when the trigger frame sent by the next first communication device satisfies a preset condition, the next first communication device actively sends a failure frame to the main communication devices in the first communication device group for notifying the main communication devices that the next first communication device cannot successfully receive channel information fed back by at least one second communication device, so that the main communication device or the next first communication device sends the transmission opportunity transfer frame to another first communication device that is located after the next first communication device and adjacent to the next communication device according to the above identified arrangement order, the opportunity of asking for the channel information is transferred to other first communication equipment in time, so that when a certain AP cannot acquire the channel information, the acquisition of the channel information by other APs and the subsequent joint transmission of multiple APs cannot be influenced, and the efficiency of acquiring the channel information is greatly improved.

In a possible design, the sending, by at least one first communication device in the first communication device group, a trigger frame to at least one second communication device specifically includes:

a master communication device in a first communication device group sends at least one trigger frame to at least one second communication device; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

In the possible design, the auxiliary communication device does not need to send a trigger frame, and only needs to acquire the required channel information in an interception mode, so that the air interface overhead of the auxiliary communication device is reduced.

In one possible design, the method further includes:

the method comprises the steps that a primary communication device sends a retransmission bitmap trigger frame to an auxiliary communication device, wherein the retransmission bitmap trigger frame is used for requesting the auxiliary communication device for receiving channel information fed back by the auxiliary communication device aiming at least one second communication device;

and the main communication equipment receives the retransmission bit map frame sent by the auxiliary communication equipment, wherein the retransmission bit map frame carries the receiving condition of the channel information fed back by the auxiliary communication equipment aiming at the at least one second communication equipment.

In one possible design, the retransmission bitmap trigger frame includes: information of a frame type identification and at least one secondary communication device;

retransmitting the bitmap frame includes: the secondary communication device comprises an identification field of at least one second communication device and a feedback fragment retransmission bitmap field corresponding to the at least one second communication device, wherein one feedback fragment retransmission bitmap field is used for indicating the receiving condition of the channel information fed back by the secondary communication device aiming at one second communication device.

In the method provided by the possible design, the primary communication device in the first communication device group sends the retransmission bitmap trigger frame through the secondary communication device to request to acquire the receiving condition of the channel information fed back by the secondary communication device for the at least one second communication device, and acquires the receiving condition of the channel information fed back by the secondary communication device for the at least one second communication device according to the received retransmission bitmap frame sent by the secondary communication device, so that the condition that the time delay for acquiring the channel information is increased due to non-intercommunication between the first communication devices is avoided, and the feedback efficiency of the channel information is further improved.

a master communication device of a first communication device group transmits a first NDPA frame to at least one second communication device, the first NDPA frame including: the first identification, the number field of the first communication equipment in the first communication equipment group, the identification list field of the first communication equipment in the first communication equipment group, the number field of the second communication equipment in the second communication equipment group and the information field of each second communication equipment; the identification list field is used for representing the identification arrangement sequence of the first communication equipment in the first communication equipment group, the information field of the second communication equipment is used for representing the identification of the second communication equipment and the channel detection indication parameter, and the first identification is used for representing the type of the first NDPA frame;

the secondary communication device in the first communication device group transmits a second NDPA frame to the at least one second communication device, the second NDPA frame including: the second identifier is used for representing the type of the second NDPA frame, and the length of the first NDPA frame is larger than that of the second NDPA frame.

In the method provided by the possible design, both the primary communication device and the secondary communication device can send the NDPA frame to the second communication device, which improves the diversity of sending the NDPA and expands the application range of the communication scene.

In a second aspect, an embodiment of the present application provides a channel sounding method, which is applied to a communication system including a first communication device group and a second communication device group participating in channel sounding, where the first communication device group includes at least one first communication device, and the second communication device group includes at least one second communication device; the method comprises the following steps:

a second communication device in the second communication device group receives a null data packet declaration (NDPA) frame sent by at least one first communication device in the first communication device group, wherein the NDPA frame is used for indicating the first communication device group and the second communication device group which participate in channel detection, and the channel detection comprises channel information of a channel between the at least one first communication device and the at least one second communication device;

a second communication device in the second communication device group receives a Null Data Packet (NDP) sent by each first communication device in the first communication device group, and probes channel information between the second communication device and at least one first communication device according to the NDP;

at least one second communication device in the second communication device group receives a trigger frame sent by at least one first communication device in the first communication device group, wherein the trigger frame is used for triggering the at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

at least one second communication device in the second communication device group feeds back channel information to at least one first communication device in the first communication device group.

In a possible design, the receiving, by the second communication device in the second communication device group, the NDPA frame sent by at least one first communication device in the first communication device group specifically includes:

the second communication device in the second communication device group receives an NDPA frame sent by the master communication device in the first communication device group, and the NDPA frame is further used for indicating the identifier permutation order of the first communication device in the first communication device group and a channel sounding indication parameter required when the at least one second communication device acquires channel information.

In a possible design, feeding back channel information to at least one first communication device in a first communication device group by at least one second communication device in the second communication device group specifically includes:

and at least one second communication device in the second communication device group feeds back channel information to at least one first communication device in the first communication device group according to the identification arrangement sequence of the first communication device in the first communication device group.

In a possible design, the receiving, by at least one second communication device in the second communication device group, the trigger frame sent by at least one first communication device in the first communication device group specifically includes:

at least one second communication device in the second communication device group receives at least one trigger frame sent by the main communication device in the first communication device group; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

a second communication device in the second communication device group receives a first NDPA frame sent by a master communication device in the first communication device group, where the first NDPA frame includes: the first identification, the number field of the first communication equipment in the first communication equipment group, the identification list field of the first communication equipment in the first communication equipment group, the number field of the second communication equipment in the second communication equipment group and the information field of each second communication equipment; the identification list field is used for representing the identification arrangement sequence of the first communication equipment in the first communication equipment group, the information field of the second communication equipment is used for representing the identification of the second communication equipment and the channel detection indication parameter, and the first identification is used for representing the type of the first NDPA frame;

receiving, by a second communication device in the second communication device group, a second NDPA frame sent by a secondary communication device in the first communication device group, where the second NDPA frame includes: the second identifier is used for representing the type of the second NDPA frame, and the length of the first NDPA frame is larger than that of the second NDPA frame.

The beneficial effects of the method provided by the second aspect and the possible designs of the second aspect may refer to the beneficial effects that can be brought by the possible designs of the first aspect and the first aspect, and are not described herein again.

In one possible design, the NDPA frame includes: a number of first communication devices in the first communication device group field, an identification list of first communication devices in the first communication device group field, a number of second communication devices in the second communication device group field, and an information field of each second communication device;

the identification list field is used for representing the identification arrangement sequence of the first communication equipment in the first communication equipment group, and the information field of the second communication equipment is used for representing the identification of the second communication equipment and the channel detection indication parameter.

The frame format of the NDPA frame provided by the possible design can enable the second communication device to know the identifier arrangement sequence of the first communication device through the identifier list field, so that the channel information is fed back based on the identifier arrangement sequence, the second communication device can conveniently obtain the channel information in time, and the processing complexity of feeding back the channel information between one second communication device and a plurality of first communication devices at the same time is greatly reduced; meanwhile, the frame format is simple in design, and the difficulty and complexity of the second communication device in analyzing the NDPA frame are reduced.

In one possible design, the trigger frame includes information of at least one target communication device;

the information of the target communication equipment is used for indicating the target communication equipment to acquire channel information between the target communication equipment and part or all of the equipment in the first communication equipment group; the target communication device is a second communication device selected by the first communication device sending the trigger frame.

In a possible design, the information of the target communication device includes an identifier of the target communication device and at least one piece of feedback indication information, and one piece of feedback indication information corresponds to one first communication device;

the feedback indication information is used for indicating to the target communication device that the first communication device sending the trigger frame needs to acquire channel information between the target communication device and the first communication device corresponding to the feedback indication information.

In a possible design, in the information of the target communication device, an order of each piece of feedback indication information in the at least one piece of feedback indication information is the same as an identification arrangement order of the first communication devices in the first communication device group.

In one possible design, the information of the target communication device further includes: and the identifier of the first communication equipment corresponding to the feedback indication information is adjacent to the identifier of the first communication equipment corresponding to the feedback indication information.

In a possible design, the feedback indication information is further used to indicate to the target communication device that the first communication device that sends the trigger frame needs to acquire the fragmentation information of the channel information between the target communication device and the first communication device corresponding to the feedback indication information.

In the method provided by each possible design, through the structure of the trigger frame designed above, the first communication device that sends the trigger frame can obtain the channel information between the second communication device and at least one first communication device through the trigger frame, and the second communication device can also send the channel information to the first communication device that is not associated with the second communication device, which greatly improves the feedback efficiency of the channel information.

In one possible design, the channel information is carried in a beamforming report.

In one possible design, the beamforming report includes: a frame identification, at least one first multiple-input multiple-output, MIMO, control field, and channel information associated with the first MIMO control field; the channel information related to the first MIMO control field is the channel information between the target communication equipment and the first communication equipment related to the first MIMO control field; wherein a first MIMO control field is associated with a first communication device corresponding to a feedback indication information;

the first MIMO control field includes: the identification of the first communication device related to the first MIMO control field and the identification of the first communication device corresponding to the last feedback indication information in the at least one feedback indication information are obtained; the frame identity is used to characterize the beamforming report as a report containing channel information between the target communication device and at least one first communication device participating in channel sounding.

According to the beam forming report provided by the possible design, the first communication device can acquire the channel information between the second communication device and the at least one first communication device through simple analysis operation, and the frame format of the beam forming report is simple, so that the complexity of acquiring the channel information by the first communication device is reduced.

In one possible design, the beamforming report includes: the frame identification, a second multiple-input multiple-output (MIMO) control field and channel information between the target communication equipment and the first communication equipment corresponding to each piece of feedback indication information; the frame identification is used for characterizing the beamforming report as a report containing channel information between the target communication device and the at least one first communication device;

wherein the second MIMO control field comprises: at least one first MIMO control field, one first MIMO control field being associated with a first communication device corresponding to one feedback indication information, the first MIMO control field comprising: an identity of the first communication device associated with the first MIMO control field, an identity of the first communication device corresponding to a last feedback indication information of the at least one feedback indication information.

The frame format of the beamforming report provided by the possible design increases the diversity of the beamforming report format, has a simple structure, and reduces the complexity of the first communication device for acquiring the channel information.

In one possible design, the beamforming report includes: the frame identification, a third multiple-input multiple-output (MIMO) control field and channel information between the target communication equipment and the first communication equipment corresponding to each piece of feedback indication information; the frame identification is used for characterizing the beamforming report as a report containing channel information between the target communication device and the at least one first communication device;

wherein the third MIMO control field comprises: the target communication device feeds back the channel information between the first communication devices corresponding to the at least one piece of feedback indication information, and the fragment indication field corresponding to the first communication device corresponding to each piece of feedback indication information; the fragment indication field is used for indicating the number of the remaining channel information fragments which are not fed back by the target communication equipment;

in the third MIMO control field, the number of repetitions of the common part is zero, and the common part includes a number field of the first communication devices corresponding to the at least one feedback indication information and an identification arrangement order field of the first communication devices corresponding to the at least one feedback indication information.

The method provided by the possible design increases the diversity of the beam forming report format, and in addition, the repetition times of the common part in the third MIMO control field is zero, so the signaling overhead of the beam forming report is small, the frame format is simple, and the complexity of the first communication equipment for acquiring the channel information is reduced

In a third aspect, to implement the method for channel sounding in the first aspect, an embodiment of the present application provides a communication network element, where the communication network element is a first communication device related to the first aspect, and the first communication device has a function of implementing the method for channel sounding. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions. Optionally, the first communication device may be an AP, and the second communication device may be a STA.

In a possible implementation manner of the third aspect, the first communication device includes a plurality of functional modules or units, and is configured to implement the method for channel sounding in any of the above-described first aspects.

In another possible implementation manner of the third aspect, the first communication device may include a processor and a transceiver in a structure. The processor is configured to support the first communication device to perform corresponding functions in any of the above-described methods for channel sounding in the first aspect. The transceiver is used for supporting communication between the first communication device and other network devices or terminal devices, and may be a corresponding radio frequency module or a baseband module, for example. The first communication device may also include a memory, coupled to the processor, that stores program instructions and data necessary for the first communication device to perform the above-described method of channel sounding.

In a fourth aspect, in order to implement the method for channel sounding in the second aspect, an embodiment of the present application provides a communication network element, where the communication network element is the second communication device in the above aspects, and the second communication device has a function of implementing the method for channel sounding in the above aspects. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions. Optionally, the second communication device may be a STA.

In a possible implementation manner of the fourth aspect, the second communication device includes a plurality of functional modules or units, and is configured to implement the method for channel sounding according to any one of the second aspect.

In another possible implementation manner of the fourth aspect, the second communication device may include a processor and a transceiver in its structure. The processor is configured to support the second communication device to perform the corresponding functions of the method for channel sounding of any of the second aspects. The transceiver is configured to support communication between the second communication device and other network devices or APs, and may be a corresponding radio frequency module or a baseband module, for example. The second communication device may also include a memory, coupled to the processor, that stores program instructions and data necessary for the second communication device to perform the above-described method of channel sounding.

In a fifth aspect, an embodiment of the present application provides a computer storage medium for storing computer software instructions for the first communication device, which includes a program designed to execute the first aspect.

In a sixth aspect, an embodiment of the present application provides a computer storage medium for storing computer software instructions for the second communication device, which includes a program designed to execute the second aspect.

In a seventh aspect, the present application provides a computer program product, where the computer program product includes a computer program, and when the computer program product is read and executed by a processor or other type of chip, the computer program product may implement the method for channel sounding provided in the foregoing embodiments of the present application. The advantages and specific working principle achieved by the computer program product refer to the foregoing embodiments, and are not described in detail herein.

In an eighth aspect, an embodiment of the present application further provides a communication system, where the system includes a first communication device group and a second communication device group;

a first communication device of a first communication device group for performing the method provided in the first aspect and in each possible design of the first aspect;

a second communication device of the second communication device group for performing the method as provided in the second aspect and in each possible design of the second aspect.

Compared with the prior art, the channel detection method, the communication device and the computer-readable storage medium provided by the application, transmitting a trigger frame by at least one first communication device of a first group of communication devices to at least one second communication device, the trigger frame is used for asking at least one second communication device for channel information between the at least one second communication device and the at least one first communication device, so that each second communication device can not only feed back channel information to the first communication device which sends the trigger frame, but also feed back channel information to other first communication devices in the first communication device group, that is, in this embodiment, the second communication device feeds back the channel information to one or more first communication devices under the indication of the trigger frame.

Drawings

FIG. 1 is a schematic diagram of a channel sounding process of 802.11ac provided herein;

fig. 2 is a schematic diagram illustrating a process of performing channel sounding between multiple APs and multiple STAs in the prior art provided by the present application;

FIG. 3 is an architecture diagram of a communication system provided herein;

fig. 4 is a schematic structural diagram of a WLAN system provided in the present application;

fig. 5 is a signaling flowchart of a first embodiment of a channel sounding method provided in the present application;

fig. 5a is a schematic diagram of an NDPA frame structure provided in the present application;

fig. 5b is a frame structure diagram of a first NDPA frame provided in the present application;

fig. 5c is a frame structure diagram of a second NDPA frame provided in the present application;

fig. 5d is a schematic diagram of a frame structure of a trigger frame provided in the present application;

fig. 5e is a diagram illustrating a beamforming report provided herein;

fig. 5f is a schematic diagram of a frame format of a VHE MIMO control field provided in the present application;

fig. 5g is a diagram of a beamforming report provided herein;

fig. 5h is a first schematic diagram of a frame format of a VHE mimo control for all Aps field provided in the present application;

fig. 5i is a schematic diagram of a frame format of a VHE mimo control for all Aps field provided in the present application;

fig. 5j is a schematic diagram of a frame format of a ReTx Bitmap trigger provided in the present application;

fig. 5k is a schematic diagram of a frame structure of a retransmitted bitmap frame provided in the present application;

fig. 6a is a first schematic diagram illustrating a frame interaction process of channel sounding provided in the present application;

fig. 6b is a schematic diagram illustrating a frame interaction flow of channel sounding according to the present application;

fig. 7 is a signaling flowchart of a second embodiment of a channel sounding method provided in the present application;

fig. 8 is a signaling flowchart of a third embodiment of a channel sounding method provided in the present application;

fig. 9 is a schematic diagram illustrating a frame interaction flow of channel sounding provided in the present application;

fig. 10 is a flowchart illustrating a fourth embodiment of a channel sounding method provided in the present application;

fig. 11 is a fourth schematic diagram illustrating a frame interaction flow of channel sounding provided in the present application;

fig. 12 is a signaling flowchart of a fifth embodiment of a channel sounding method provided in the present application;

fig. 13 is a schematic diagram illustrating a frame interaction flow of channel sounding according to the present application;

fig. 14 is a schematic structural diagram of a first embodiment of a communication device provided in the present application;

fig. 15 is a schematic structural diagram of a second embodiment of a communication device provided in the present application;

fig. 16 is a schematic structural diagram of a third embodiment of a communication device provided in the present application;

fig. 17 is a schematic structural diagram of a fourth embodiment of a communication device provided in the present application.

Detailed Description

The channel sounding method and apparatus provided in the present application may be applied to the communication system shown in fig. 3, where the communication system includes a first communication device group and a second communication device group participating in channel sounding. Wherein the first communication device group comprises at least one first communication device and the second communication device group comprises at least one second communication device. Optionally, the communication system may be a Wireless Local Area Network (WLAN) system, and may also be a network system of other systems, for example: global System for Mobile communications (GSM) System, Code Division Multiple Access (CDMA) System, Wideband Code Division Multiple Access (WCDMA) System, Time Division-Synchronous Code Division Multiple Access (TD-SCDMA), Long Term Evolution (LTE) System, and future 5G System.

Taking the communication system shown in fig. 3 as a WLAN system as an example, a Station (STA) and an Access Point (AP) are basic constituent devices of the WLAN system. The AP is an access point for a mobile user to enter a wired network, and is mainly deployed in a home, a building, and a campus, and typically has a coverage radius of several tens of meters to hundreds of meters, or may be deployed outdoors. The AP acts as a bridge connecting the network and the wireless network, and mainly functions to connect the wireless network clients together and then to access the wireless network to the ethernet. Specifically, the AP may be a device with a WiFi (Wireless Fidelity, chinese) chip, for example, a terminal device or a network device with a WiFi chip. Optionally, the AP may be a device supporting 802.11ax standard, and further optionally, the AP may be a device supporting multiple WLAN standards such as 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a, and the type of the standard supported by the AP is not limited in this embodiment.

STAs are typically terminal devices in WLAN systems. The STA may be mobile or fixed, and is the most basic component device of the wireless local area network, and may be a wireless communication chip, a wireless sensor or a wireless communication terminal. For example: the mobile phone supporting the WiFi communication function, the tablet computer supporting the WiFi communication function, the set top box supporting the WiFi communication function, the smart television supporting the WiFi communication function, the smart wearable device supporting the WiFi communication function, the vehicle-mounted communication device supporting the WiFi communication function and the computer supporting the WiFi communication function.

In the WLAN system, the first communication device may be an AP and the second communication device may be a STA, and optionally, the first communication device may be a STA and the second communication device may be an AP. Optionally, in the WLAN system, the AP and the AP may communicate with each other, and the STA may also communicate with each other. Illustratively, taking the first communication device as an AP and the second communication device as an STA as an example, fig. 4 shows a schematic structural diagram of a WLAN system based on the AP and the STA, as shown in fig. 4, 1 AP in the WLAN system may perform information interaction with multiple STAs (2 in the figure as an example), which includes STA1 and STA 2. The following embodiments are described by taking the first communication device as an AP and the second communication device as an STA as an example.

It should be understood that although the terms first, second, third, etc. may be used to describe XXX in embodiments of the present invention, these XXX should not be limited to these terms. These terms are only used to distinguish XXX from each other. For example, a first XXX may also be referred to as a second XXX, and similarly, a second XXX may also be referred to as a first XXX, without departing from the scope of embodiments of the present invention.

As shown in fig. 2, in the conventional 802.11 ac-based channel Sounding (Sounding) process, in order to improve the applicability of channel Sounding, in the WLAN, a plurality of APs and a plurality of STAs perform channel Sounding, first, an AP1 sends an NDPA frame and an NDP, then, an AP2 sends the NDP, then, an STA11 starts to feed back a Beamforming Report (BFR) to its associated AP1, and then, the AP1 continues to request for a BFR from the STA12 through a BRP frame. After the AP1 finishes requesting channel state information from its associated STAs, the AP1 sends a Start Poll (SP) frame to the AP2 to inform the AP2 to continue requesting channel state information from STAs associated with the AP 2. However, in the channel sounding process based on 802.11ac, the STA can only feed back the BFR to the AP associated with the STA, the range of the feedback object is limited, and the feedback efficiency of the CSI is low.

In order to solve the above technical problem, the present application provides a method for channel sounding, where at least one first communication device in a first communication device group sends a trigger frame to at least one second communication device in a second communication group, and the trigger frame is used to ask for channel information between the at least one second communication device and the at least one first communication device from the at least one second communication device, so that the at least one second communication device can not only feed back the channel information to the first communication device that sent the trigger frame, but also feed back the channel information to other first communication devices in the first communication device group. Optionally, the channel information may be carried in a Beamforming Report (BFR) for transmission, and each fed back BFR includes channel information between the second communication device and at least one first communication device in the first communication device group, where the channel information may be CSI, CQI, and other information related to channel state and quality.

The technical solution of the present application will be described in detail below with specific examples. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments.

Fig. 5 is a signaling flowchart of a first embodiment of a channel sounding method provided in the present application. The present embodiment relates to a process in which, during a channel detection process of at least one first communication device and at least one second communication device, the first communication device may ask for channel information between the at least one second communication device and the at least one first communication device from the at least one second communication device through a trigger frame provided in this embodiment, so that the at least one second communication device may feed back the channel information between the at least one first communication device and the at least one second communication device to the at least one first communication device. As shown in fig. 5, the method includes:

s101: at least one first communication device in the first communication device group transmits an NDPA frame indicating the first communication device group and the second communication device group participating in channel sounding, wherein the channel sounding includes channel information sounding a channel between the at least one first communication device and the at least one second communication device.

Specifically, the first communication device group and the second communication device group include a plurality of devices participating in channel sounding, in this application, the first communication device group may include at least one first communication device, and the second communication device group may include at least one second communication device. Optionally, one of all the first communication devices included in the first communication device group may be used as a primary communication device, and the other remaining first communication devices may be used as secondary communication devices.

When a first communication device in a first communication device group needs to acquire channel information with a second communication device in a second communication device group, the first communication device in the first communication device group initiates a channel detection procedure, that is: at least one first communication device in the first communication device group sends an NDPA frame, where the NDPA frame may be used to indicate the first communication device group and the second communication device group participating in channel sounding, and the channel sounding in this application may include sounding channel information of a channel between the at least one first communication device and the at least one second communication device.

Optionally, the NDPA frame may be sent by the primary communication device in the first communication device group, or may be sent by the primary communication device and the secondary communication device in the first communication device group, respectively. The second communication device in the second communication device group may know that it is a device participating in channel sounding by listening to the NDPA frame.

In the case that the NDPA frame is transmitted by the master communication device in the first communication device group, the NDPA frame may also be used to indicate an identification arrangement order of the first communication devices in the first communication device group and a channel sounding indication parameter required when the at least one second communication device acquires channel information with the at least one first communication device. Optionally, the channel sounding indication parameter may include, for example: a Sounding Dialog Token (Sounding Dialog Token) field, Partial bandwidth information (Partial BW Info), Feedback Type (Feedback Type), Ng (number of grouping subcarriers) information, Codebook size field, and other information common to the first communication device in the first communication device group, wherein the Feedback Type field and the Ng field may be located in the same field, see the Feedback Type and Ng field in fig. 5 a; in addition, the channel sounding indication parameter may further include: information indicated for each AP, such as the Number of columns of channel information (Nc) that each AP needs to acquire, is taken as Nc as an example, where "information indicated for each AP" refers to different APs and the value of Nc is different. The format of the NDPA frame is not limited in this embodiment, as long as the NDPA frame can indicate the first communication device group and the second communication device group participating in the channel sounding, or as long as the NDPA frame can indicate the first communication device group and the second communication device group participating in the channel sounding, indicate the identifier arrangement order of the first communication device in the first communication device group, and indicate a channel sounding indication parameter required when the at least one second communication device acquires the channel information.

Optionally, as an optional implementation manner of the NDPA frame, the NDPA frame may include: the number field of first communication equipment in a first communication equipment group, the identification list field of first communication equipment in the first communication equipment group, the number field of second communication equipment in a second communication equipment group and the information field of each second communication equipment; the identification list field is used for representing the identification arrangement sequence of the first communication equipment in the first communication equipment group, and the information field of the second communication equipment is used for representing the identification of the second communication equipment and the channel detection indication parameter. Optionally, taking the first communication device as an AP and the second communication device as an STA as an example, the frame structure of the NDPA frame may be as shown in fig. 5 a.

Taking fig. 5a as an example, the number field of the first communication device in the first communication device group is an "AP number" field, and the identification list field of the first communication device in the first communication device group is an "AP ID list" field, where the field is used to characterize the identification arrangement order of the first communication device in the first communication device group (i.e. the identification arrangement order of the APs), for example, according to the number (e.g. 5) indicated by the AP number field, the AP ID list includes a plurality of AP IDs, which are sequentially: AP ID1, AP ID 2, AP ID3, AP ID4, AP ID 5; the number field of the second communication device in the second communication device group is a "number of STAs" field, and the information field of the second communication device is a "STA info" field, where the field is used to represent the identifier of the second communication device and a channel sounding indication parameter when the second communication device acquires channel information. As shown in fig. 5a, the STA Info field includes Association Identifier (AID), Partial bandwidth information (Partial BW Info), feedback Type and ng (feedback Type and ng), and Nc; the AID is an identifier of an STA participating in channel sounding; partial bandwidth information (Partial BW Info) for indicating the STA to feed back channel state information of the Partial bandwidth; a Feedback Type (Feedback Type) is used to indicate whether the current Feedback is single-user Feedback or multi-user Feedback; ng is used to indicate grouping information of sub-carriers; nc is used to indicate the number of columns of channel information requested by the AP, each column corresponding to a first communication device, and it should be noted that the value of Nc is different for different APs. In addition, the AID, the Partial BW Info, the Feedback Type and Ng, and the Codebook size may be information common to the APs in the first communication device group, that is, the STA may all use the channel sounding indication parameter when acquiring the channel information with at least one AP. Optionally, the NDPA Frame related in the present application is a MAC Frame, so that a Frame format of the NDPA Frame may further include a Frame Control (FC) field that is common to the MAC Frame, where the FC field includes fields of a type and a subtype of the MAC Frame, and is used to identify the type of the MAC Frame; a Receiving Address field (RA) and a Transmitting Address field (TA) for identifying a Receiving end and a Transmitting end of the MAC frame. In addition, the probe Dialog Token (Sounding Dialog Token) field in fig. 5a is used to index the sequence number of the channel probe.

Optionally, as another optional implementation manner of the NDPA frame, the NDPA frame may be sent by the primary communication device and the secondary communication device in the first communication device group, and this manner may improve reliability of NDPA frame transmission, thereby improving efficiency of the second communication device in listening to the NDPA frame. It should be noted that, when the primary communication device and the secondary communication device in the first communication device group respectively send the NDPA frame, the primary communication device sends the first NDPA frame, the secondary communication device sends the second NDPA frame, the frame formats of the first NDPA frame and the second NDPA frame are different, and the length of the first NDPA frame is greater than that of the second NDPA frame. In addition, when the first NDPA frame and the second NDPA frame are transmitted, the following may be specifically performed: for example, referring to a first frame interaction flow diagram of channel sounding shown in fig. 6a, assuming that a first communication device group includes AP1, AP2, and AP3, a second communication device group includes STA1 and STA2, and an AP1 serving as a main communication device first transmits the first NDPA frame, then after an SIFS interval, AP1 transmits NDP1, immediately after the AP2 transmits the second NDPA frame, after the SIFS interval, AP2 transmits NDP2, and finally, after the AP3 transmits the second NDPA frame, after the SIFS interval, the AP3 transmits NDP 3. The first NDPA frame may be used to indicate a first communication device group and a second communication device group participating in channel sounding, and may also be used to indicate an identification arrangement order of first communication devices in the first communication device group and a channel sounding indication parameter required when at least one second communication device acquires channel information with at least one first communication device, where the indicated channel sounding indication parameter only includes information related to a primary communication device, for example, only includes Nc of the primary communication device, and the second NDPA frame may be used to indicate the second communication device group participating in channel sounding and Nc information related to each device in the second communication device group and the secondary communication device.

Optionally, the first NDPA frame may include a first identifier, a number of first communication devices in the first communication device group field, an identifier list field of the first communication devices in the first communication device group, a number of second communication devices in the second communication device group field, and an information field of each second communication device; the identifier list field is used to characterize an identifier permutation order of a first communication device in the first communication device group, the information field of the second communication device is used to characterize an identifier of the second communication device and the channel sounding indication parameter, and the first identifier is used to characterize a type of the first NDPA frame. Note that, unlike the configuration of the NDPA frame shown in fig. 5a, the channel sounding indication parameters indicated by the information field of the second communication device group in the NDPA frame indicated in fig. 5a may indicate not only the information of the primary communication device but also the information of the secondary communication device, for example, Nc (AP1) … … Nc (apk) is included in the indicated Nc, but only the information of the primary communication device is included in the channel sounding indication parameters indicated by the information field of the second communication device in the first NDPA frame, for example, only the Nc (AP1) of the primary communication device is included in the indicated Nc. Further, compared with the NDPA frame shown in fig. 5a, the first NDPA frame has a first flag added, and the first flag may be located at any position in the NDPA frame shown in fig. 5a by adding a bit, so as to form the first NDPA frame, or the first flag may be carried by a reserved bit in a Sounding Dialog Token, so as to represent that the first NPD frame is a Long NDPA frame. Alternatively, the structure of the first NDPA frame may be as shown in fig. 5 b.

Optionally, the second NDPA frame may include: a second identifier, a number field of second communication devices in the second communication device group, and an information field of each second communication device, where the second identifier is used to characterize a type of the second NDPA frame, and a length of the first NDPA frame is greater than a length of the second NDPA frame. The frame format of the second NDPA frame may be as shown in fig. 5 c. Compared with the first NDPA shown in fig. 5a, the STA Info of the first NDPA frame includes Nc of the primary communication device, the information field of the second communication device of the second NDPA frame includes Nc of the secondary communication device (i.e., which secondary communication device the second NDPA frame transmits, and Nc is corresponding to which secondary communication device), and the STA receiving the second NDPA frame may determine the fields of AID, Partial BW Info, Feedback Type and Ng, and Codebook size through the Sounding Dialog Token of the second NDPA frame. Optionally, the second identifier in the second NDPA frame may be implemented by adding a bit, or may be implemented by a reserved bit in a Sounding Dialog Token, so as to indicate that the second NDPA frame is a Short NDPA frame. The length of the first NDPA frame is greater than the length of the second NDPA frame. Optionally, the first NDPA frame and the second NDPA frame are transmitted in a bundled manner, where "bundled" is to be understood to mean that once the primary communication device transmits the first NDPA frame, the secondary communication device transmits the second NDPA frame accordingly.

S102: the second communication device in the second communication device group receives the NDPA frame transmitted by at least one first communication device in the first communication device group.

After the second communication device in the second communication device group receives the NDPA frame, it can be known that the second communication device is the second communication device participating in the current channel sounding through the NDPA frame, and it can also be known that the first communication device participating in the current channel sounding through the NDPA frame. Optionally, the channel sounding indication parameter required in channel sounding may also be known through the NDPA frame.

S103: each first communication device in the first communication device group sends an NDP to a second communication device in the second communication device group, wherein the NDP is used for the second communication device to detect channel information with at least one first communication device.

S104: and the second communication equipment in the second communication equipment group receives the null data packet NDP sent by each first communication equipment in the first communication equipment group, and detects the channel information between the second communication equipment and at least one first communication equipment according to the NDP.

Specifically, after at least one first communication device in the first communication device group transmits the NDPA frame, optionally, after a Short Inter-frame Space (SIFS) interval, each first communication device in the first communication device group transmits the NDP to a second communication device in the second communication device group, and optionally, the transmission mode of the NDP and the NDPA frame may be transmitted in a broadcast form. Different first communication devices respectively send the NDP, and after receiving the NDP sent by the different first communication devices, a second communication device in the second communication device group may probe channel information between the second communication device and at least one first communication device sending the NDP according to the received NDP.

For example, referring to the second channel sounding procedure diagram shown in fig. 6b, assuming that the first communication device group includes AP1 and AP2, and the second communication device group includes STA1 and STA2, the AP1 in the first communication device group transmits an NDPA frame to the second communication device group, and then after an SIFS interval, the AP1 transmits an NDP1, and then the AP2 transmits an NDP2 (optionally, when the AP1 and the AP2 transmit an NDP, the NDP may be transmitted in the order of APs in the AP ID list in fig. 5a, or may not be transmitted in the order of APs in the AP ID list, which is not limited in this embodiment). When both the STA1 and the STA2 sense the NDP1 and the NDP2, the STA1 estimates a channel between the STA1 and the AP1 according to the NDP1 to obtain channel information of the STA1-AP1, and optionally, the STA1 also estimates a channel between the STA1 and the AP2 according to the NDP2 to obtain channel information of the STA1-AP 2; the STA2 estimates the channel between the STA2 and the AP1 according to the NDP1 to obtain the channel information of the STA2-AP1, and optionally, the STA2 also estimates the channel between the STA2 and the AP2 according to the NDP2 to obtain the channel information of the STA2-AP 2.

S105: at least one first communication device in the first communication device group sends a trigger frame to at least one second communication device in the second communication device group, wherein the trigger frame is used for triggering the second communication device to feed back channel information between the at least one second communication device and the at least one first communication device.

For example, in fig. 6b, the AP1 broadcasts a trigger frame for triggering STA1 and STA2 to feed back channel information, which specifically includes: triggering STA1 to feed back channel information between STA1 and AP1 and channel information between STA1 and AP 2; further comprising: the triggering STA2 feeds back channel information between STA2 and AP1 and channel information between STA2 and AP 2.

Specifically, after each first communication device in the first communication device group sends an NDP, at least one first communication device in the first communication device group may send a Trigger frame (BF Report Trigger, abbreviated as BRP Trigger) sending manner to the second communication device in the second communication device group, which may be a broadcast manner. The trigger frame is used for triggering the second communication device to feed back channel information between the at least one second communication device and the at least one first communication device.

S106: at least one second communication device in the second communication device group receives the trigger frame.

S107: and feeding back channel information to at least one first communication device in the first communication device group by at least one second communication device in the second communication device group according to the trigger frame.

S108: at least one first communication device in the first communication device group receives the channel information fed back by the at least one second communication device.

Specifically, after at least one second communication device in the second communication device group receives the trigger frame, the content of the trigger frame and the indication function are combined, and channel information between the second communication device and the at least one first communication device is fed back to the at least one first communication device in the first communication device group. Optionally, when feeding back the channel information, at least one second communication device in the second communication device group may feed back the channel information in a multicast form, or may feed back the channel information in a broadcast form, and a first communication device in the first communication device group may obtain channel information required by itself in an interception manner, where the feedback manner of the channel information is not limited in this embodiment.

It should be noted that, in this embodiment, the content of the channel information fed back by the second communication device depends on the content to be requested by the trigger frame sent by the first communication device, that is, the first communication device may notify the second communication device through a trigger frame, and the first communication device needs to acquire the channel information between the second communication device and any first communication device in the first communication device group, so that the channel information fed back by the second communication device is the channel information between the second communication device and the first communication devices; optionally, the first communication device may also notify, through a trigger frame, the plurality of second communication devices, where the first communication device needs to acquire channel information between which second communication devices in the second communication device group and which first communication devices in the first communication device group, and then the channel information fed back by the corresponding second communication device includes channel information between the second communication device and the corresponding first communication device. For example, in fig. 6b, after receiving a trigger frame broadcast by AP1 by STA1 and STA2, respectively, in combination with the trigger frame, STA1 learns that AP1 not only needs to acquire channel information between STA1 and AP1 but also needs to acquire channel information between STA1 and AP2, in addition, STA2 learns that AP1 needs to acquire channel information between STA2 and AP1 and between STA2 and AP2 by combining with the trigger frame, channel information fed back to AP1 by STA1 includes channel information between STA1-AP1 and STA1-AP2, and channel information fed back by STA2 includes channel information between STA2-AP1 and STA2-AP 2. In addition, the frame format of the trigger frame is not limited in this embodiment, as long as the trigger frame can trigger at least one second communication device in the second communication device group to feed back channel information between the at least one second communication device and the at least one first communication device.

As can be seen from the foregoing description, in this embodiment, a trigger frame is sent to at least one second communication device by at least one first communication device in a first communication device group, where the trigger frame is used to ask for channel information between the at least one second communication device and the at least one first communication device from the at least one second communication device, so that each second communication device can not only feed back the channel information to the first communication device that sent the trigger frame, but also feed back the channel information to other first communication devices in the first communication device group, that is, in this embodiment, the second communication device feeds back the channel information to one or more first communication devices under the indication of the trigger frame, and the method of this embodiment greatly improves the feedback efficiency of the channel information.

An alternative implementation of the trigger frame referred to in the above embodiments is described in detail below:

optionally, the trigger frame may include information of at least one target communication device. The information of the target communication device is used to instruct the target communication device to acquire channel information between the target communication device and some or all devices in the first communication device group, the target communication device is a second communication device selected by the first communication device that sends the trigger frame, and the target communication device may be one or more devices. That is, the first communication device that transmits the trigger frame may select which second communication devices and which first communication devices the first communication device wants to acquire channel information through the trigger frame. In this embodiment, a specific format of the information of the target communication device included in the trigger frame is not limited, as long as the first communication device can obtain, through the trigger frame, channel information between one or more target communication devices and some or all devices in the first communication device group. For example, taking the first communication device as an AP and the second communication device as an STA as an example, the frame format of the trigger frame may be as shown in fig. 5 d:

in connection with the structure of the trigger frame shown in fig. 5d, the trigger frame may include information common to a plurality of first communication devices (i.e., common part information) and information for each STA (i.e., station-by-station information STA Info). The Common partial information (Common Info) indicates information Common to a plurality of first communication apparatuses such as sound Dialog Token, STA Info is information of the target communication apparatus, and the trigger frame shown in fig. 5d includes n target communication apparatuses, STA1 … … STAn respectively, selected by the first communication apparatus that transmits the trigger frame.

Optionally, as an optional implementation manner of the "information of the target communication device", the information of each target communication device may include: the identification of the target communication equipment and at least one piece of feedback indication information, wherein one piece of feedback indication information corresponds to one piece of first communication equipment; the feedback indication information is used to indicate to the target communication device that the first communication device that sent the trigger frame needs to acquire channel information between the target communication device and the first communication device corresponding to the feedback indication information. Optionally, the information of the target communication device may further include resource indication information, which is used to indicate a resource unit and a physical layer parameter (e.g., MCS) that the second communication device should adopt when feeding back the channel information. In this alternative implementation, the first communication device that sends the trigger frame may indicate, through the STA Info, which second communication device is the target communication device selected by itself, and indicate, through the feedback indication information, which target communication devices and which first communication devices the first communication device that sends the trigger frame wants to acquire channel information between. For example, if the trigger frame transmitted by the AP1 includes STA1 Info and STA2 Info, it indicates that the AP1 transmitting the trigger frame selects STA1 and STA2 as target communication devices, and if the STA1 Info includes feedback indication information 1 corresponding to AP1 and feedback indication information 2 corresponding to AP2, it indicates that the AP1 wants to acquire channel information between STA1 and AP1 and channel information between STA1 and AP 2.

Continuing with the example that the first communication device is an AP and the second communication device is an STA, in conjunction with the frame structure shown in fig. 5d, the STA Info field may include the following two forms, a and B:

in the form a, the order of each feedback indication information in the information (e.g., STA Info shown in fig. 5 d) of one target communication device is the same as the identification arrangement order of the first communication device in the first communication device group.

In the form a of fig. 5d, the AID is an identifier of the second communication device (i.e. an identifier of the target communication device) selected by the first communication device that transmits the trigger frame, the feedback indication information 1 indicates channel information between the STA feedback in the STA Info and the first communication device AP1, the feedback indication information 2 indicates channel information between the STA feedback in the STA Info and the first communication device AP2, and the feedback indication information K indicates channel information between the STA feedback in the STA Info and the first communication device APK. Alternatively, if the arrangement order of the APs in the AP ID list of the NDPA frame transmitted by the first communication device is AP1, AP2, and AP3 … … APK, in fig. 5d, the arrangement order of the feedback indication information is: feedback instruction information 1, feedback instruction information 2, and feedback instruction information 3 … … feedback instruction information K. Optionally, the Feedback indication information may be a Feedback Segment Transmission Bitmap (Feedback Segment Transmission Bitmap). Optionally, when the target communication device cannot feed back the channel information to the first communication device at one time, the target communication device may divide the channel information to be fed back into a plurality of segments (segments), so that the feedback indication information in the trigger frame may indicate to the target communication device that the first communication device that sends the trigger frame needs to acquire the channel information between the target communication device and the first communication device corresponding to the feedback indication information, and may also be used to indicate to the target communication device that the first communication device that sends the trigger frame needs to acquire which segments (segments) in the channel information between the target communication device and the first communication device corresponding to each piece of feedback indication information in fig. 5 d.

Form B: in this implementation, the information of a target communication device (e.g. the STA Info field in fig. 5 d) includes, in addition to the identification of the target communication device and at least one piece of feedback indication information: and the identifier of the first communication device corresponding to each piece of feedback indication information is adjacent to the identifier of the first communication device corresponding to the piece of feedback indication information.

In the B form of fig. 5d, the AID is an identifier of the second communication device (i.e. an identifier of the target communication device) selected by the first communication device that transmits the trigger frame, the feedback indication information 1 indicates channel information between the STA feedback in the STA Info and the first communication device AP1, the feedback indication information 2 indicates channel information between the STA feedback in the STA Info and the first communication device AP2, and the feedback indication information K indicates channel information between the STA feedback in the STA Info and the first communication device APK, as shown in fig. 5d, the ID of the AP1 is adjacent to the feedback indication information 1, the ID of the AP2 is adjacent to the feedback indication information 2, and so on. The Feedback indication information may be Feedback Segment Transmission Bitmap.

With the above A, B two forms, after the second communication device receives the trigger frame, it can determine whether it is the object to be triggered by the trigger frame by combining the STA Info field in the trigger frame; and then, according to the specific content of the STA Info field, determining that the first communication equipment which sends the trigger frame needs to know the channel information between the first communication equipment and the first communication equipment. .

Continuing with the above-mentioned frame interaction flowchart shown in fig. 6b as an example, assume that the first communication device group includes AP1 and AP2, and the second communication device group includes STA1 and STA2, assume that the AP1 transmits a trigger frame and carries information (STA info) of a target communication device in the trigger frame, and assume that the STA info is STA1 info (i.e., STA1 info includes ID of STA 1), and the order of the feedback indication information is feedback indication information 1 and feedback indication information 2. When the trigger frame is heard by STA1, STA1 knows that it is a target communication device in combination with AID in STA info, and AP1 wants to acquire channel information between STA1 and AP1 and AP2 in combination with the structure of the trigger frame. When STA1 feeds back channel information, the channel information includes channel information between STA1-AP1 and STA1-AP 2.

When a plurality of STA info are carried in the trigger frame, assuming that STA1 info and STA2 info, the order of the feedback indication information in STA1 info and STA2 info is feedback indication information 1 and feedback indication information 2. After the trigger frame is intercepted by STA1 and STA2, STA1 learns that it is a target communication device by combining with AID in STA1 info, and learns that AP1 wants to acquire channel information between STA1 and AP1 and AP2 by combining with the structure of the trigger frame; meanwhile, the STA2 learns that it is a target communication device in combination with AID in the STA2 info, and learns that the AP1 wants to acquire channel information between the STA2 and the

APs

1 and 2 in combination with the structure of the trigger frame. Therefore, when the STA1 feeds back the channel information, the channel information includes the channel information between the STA1-AP1 and the STA1-AP2, and when the STA2 feeds back the channel information, the channel information includes the channel information between the STA2-AP1 and the STA2-AP 2.

As can be seen from the above description, what channel information is included in the channel information fed back by the STA is determined by the content of the trigger frame.

For the channel information fed back by the second communication device, optionally, the channel information may be transmitted in a beam forming report. The beamforming report may include three alternative implementations. It should be noted that the following three alternative implementations are merely shown by way of example, and do not limit the specific content of the beamforming report, so long as the beamforming report includes channel information between the target communication device and the at least one first communication device.

The first implementation mode comprises the following steps:

in this implementation, the beamforming report includes: a frame identification, at least one first multiple-input multiple-output, MIMO, control field, and channel information associated with the first MIMO control field; the channel information associated with the first MIMO control field is the channel information between the target communication device and the first communication device associated with the first MIMO control field; wherein a first MIMO control field is associated with a first communication device corresponding to a feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device participating in channel sounding

Alternatively, the beamforming report may be an Action frame or an Action No ACK (Action without acknowledgement) frame. In at least one first MIMO control field included in the beamforming report, one first MIMO control field is associated with a first communication device corresponding to one feedback indication information in the information of the target communication device, and one first MIMO control field is associated with one channel information, where the channel information associated with the first MIMO control field is channel information between the target communication device and the first communication device associated with the first MIMO control field. Optionally, the first MIMO control field may be, for example, a VHE MIMO control field of fig. 5e, where each VHE MIMO control field corresponds to a first communication device, and indicates that the VHE MIMO control field is associated with the first communication device, for example, the VHE MIMO control for AP1, the VHE MIMO control for AP2, and so on.

Continuing with the frame interaction flow shown in fig. 6b, it is assumed that the first communication device group includes AP1 and AP2, the second communication device group includes STA1 and STA2, and it is assumed that AP1 transmits the trigger frame shown in fig. 5d, where the trigger frame includes STA1 info and STA2 info, and the order of the feedback indication information in STA1 info and STA2 info is feedback indication information 1 and feedback indication information 2, that is, the target communication devices selected by AP1 are STA1 and STA2 (the first communication device corresponding to feedback indication information 1 is AP1, and the second communication device corresponding to feedback indication information 2 is AP 2). Therefore, both STA1 and STA2 are to feed back beamforming reports to AP1 and AP 2.

Referring to the schematic diagram of the beamforming report shown in fig. 5e, in the beamforming report fed back by STA1 or STA2, two VHE MIMO control fields are included, a first VHE MIMO control field (i.e., VHE MIMO control for AP1 in fig. 5 e) of the two VHE MIMO control fields is associated with AP1 corresponding to feedback indication information 1, and another VHE MIMO control field (i.e., VHE MIMO control for AP2 in fig. 5 e) is associated with AP2 corresponding to feedback indication information 2. Therefore, when the STA1 feeds back the channel information, the channel information associated with the VHE MIMO control for AP1 (i.e. CSI/CQI/etc. for AP1 in fig. 5 e) is the channel information between STA1 and AP1, and the channel information associated with the VHE MIMO control for AP2 (i.e. CSI/CQI/etc. for AP2 in fig. 5 e) is the channel information between STA1 and AP2, that is, the beamforming report fed back by STA1 includes the channel information between STA1-AP1 and STA1-AP 2. When the channel information fed back by the STA2, the CSI/CQI/etc. for AP1 is the channel information between the STA2 and the AP1, and the CSI/CQI/etc. for AP2 is the channel information between the STA2 and the AP2, that is, the beamforming report fed back by the STA2 includes the channel information between the STA2-AP1 and the STA2-AP 2.

Further, the first MIMO control field involved in the beamforming report includes: the identifier of the First communication device related to the First MIMO control field, the identifier of the First communication device corresponding to the last Feedback indication information in at least one piece of Feedback indication information in the information of the target communication device, and some or all of the Nc index field, Nr index field, BW field, Grouping field, Codebook information field, Feedback Type field, Remaining Feedback Segment field, First Feedback Segment field, RU start index field, RU End index field, Sounding Dialog Token Number field, and Reserved field shown in fig. 5 f. Optionally, taking the first communication device as an AP and the second communication device as an STA as an example, a format of the VHE MIMO control field in fig. 5e may be as shown in fig. 5 f.

In fig. 5f, the AP ID is the identifier of the first communication device related to the VHE MIMO control field, and the Last AP is the identifier of the first communication device corresponding to the Last feedback indication information among all the feedback indication information shown in fig. 5 d. Taking the above fig. 5e as an example, the frame structures of VHE MIMIO control for AP1 and VHE MIMIO control for AP2 are both shown in fig. 5f, except that AP ID in VHE MIMIO control for AP1 is AP1, Last AP is AP2, AP ID in VHE MIMIO control for AP2 is AP2, and Last AP is AP 2.

The second implementation mode comprises the following steps:

in this implementation, the beamforming report includes: frame identification, a second MIMO control field and channel information between the target communication device and the first communication device corresponding to each feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device. The second MIMO control field comprises: at least one first MIMO control field, one first MIMO control field associated with a first communication device corresponding to one feedback indication information, the first MIMO control field comprising: the identifier of the First communication device related to the First MIMO control field, the identifier of the First communication device corresponding to the last Feedback indication information in the at least one Feedback indication information, and some or all of the Nc index field, the Nr index field, the BW field, the Grouping field, the Codebook information field, the Feedback Type field, the Remaining Feedback Segment field, the First Feedback Segment field, the RU start index field, the RU End index field, the Sounding Dialog Token Number field, and the Reserved field shown in fig. 5 f.

Alternatively, the beamforming report may be an Action frame or an Action No ACK (Action without acknowledgement) frame. The beamforming report includes a second MIMO control field, and the second MIMO control field includes at least one first MIMO control field.

Continuing with the frame interaction procedure shown in fig. 6b, it is assumed that the first communication device group includes AP1 and AP2, and the second communication device group includes STA1 and STA2, and it is assumed that AP1 transmits a trigger frame having the structure shown in fig. 5d, where the trigger frame includes STA1 info and STA2 info, and the order of the feedback indication information in STA1 info and STA2 info is feedback indication information 1 and feedback indication information 2, that is, the target communication devices selected by AP1 are STA1 and STA2 (the first communication device corresponding to feedback indication information 1 is AP1, and the second communication device corresponding to feedback indication information 2 is AP 2). Therefore, both STA1 and STA2 feed back beamforming reports.

When STA1 feeds back a beamforming report, for example, the beamforming report may be as shown in fig. 5 g. In fig. 5g, Category and vhe (very High efficiency) Action are frame identifiers for identifying the beamforming report as a report containing channel information between the target communication device and at least one first communication device participating in channel sounding; VHE MIMO control for all APs is the second MIMO control field, CSI/CQI/etc. for AP1 is the channel information between STA1-AP1, and CSI/CQI/etc. for AP2 is the channel information between STA1-AP 2. With reference to the VHE MIMO control for all Aps shown in fig. 5g, a format of the VHE MIMO control for all Aps may be shown in fig. 5h, where each first MIMO control field in fig. 5h is the VHE MIMO control field in fig. 5e, and a specific format thereof may also be shown in fig. 5 f.

The third implementation mode comprises the following steps:

for the frame formats of the beamforming reports shown in the first implementation and the second implementation, some pieces of information included in the MIMO control fields are the same, so that a third implementation is introduced to save the feedback overhead of the beamforming report.

In this implementation, the beamforming report includes: frame identification, a third MIMO control field, and channel information between the target communication device and the first communication device corresponding to each feedback indication information; the third MIMO control field includes: the target communication device feeds back the channel information between the first communication devices corresponding to the at least one piece of feedback indication information, and a fragmentation indication field corresponding to the first communication device corresponding to each piece of feedback indication information, wherein the fragmentation indication field is used for indicating the number of the remaining channel information fragments which are not fed back and are of the target communication device; in the third MIMO control field, the number of repetitions of the common part is zero, the common part includes a number field of the first communication devices corresponding to the at least one piece of feedback indication information and an identifier permutation order field of the first communication devices corresponding to the at least one piece of feedback indication information, and the frame identifier is used to characterize the beamforming report as a report including channel information between the target communication device and the at least one first communication device.

Continuing with the frame interaction procedure shown in fig. 6b, it is assumed that the first communication device group includes AP1 and AP2, and the second communication device group includes STA1 and STA2, and it is assumed that AP1 transmits a trigger frame having the structure shown in fig. 5d, where the trigger frame includes STA1 info and STA2 info, and the order of the feedback indication information in STA1 info and STA2 info is feedback indication information 1 and feedback indication information 2, that is, the target communication devices selected by AP1 are STA1 and STA2 (the first communication device corresponding to feedback indication information 1 is AP1, and the second communication device corresponding to feedback indication information 2 is AP 2). Therefore, both STA1 and STA2 feed back beamforming reports. Taking the target communication device as STA1 as an example, the frame format of the beamforming report fed back by STA1 may also be as shown in fig. 5g, and the third MIMO control field may be VHE MIMO control for all Aps in fig. 5 g. Different from the format of the second MIMO control field, in this implementation, the specific format of the VHE MIMO control for all Aps may be as shown in fig. 5 i. In fig. 5i, the first behavior STA1 is configured to set the number of the APs to the number field of the first communication device corresponding to the feedback indication information and the AP ID list to the ID array sequence field of the first communication device corresponding to the feedback indication information, in conjunction with the first behavior STA in fig. 5i, when feeding back the channel information between the first communication devices corresponding to the feedback indication information 1 and the feedback indication information 2, the number of repetitions of the MIMO control field is zero. The second row in fig. 5i indicates for each first communication device corresponding to the feedback indication information, K is greater than or equal to 1. With reference to the frame interaction flow shown in fig. 6b, K is 2, where the Remaining Feedback Segment (AP1) is a Segment indication field corresponding to the first communication device corresponding to the Feedback indication information 1, and is used to indicate the number of Remaining channel information segments of the STA1 that are not fed back.

In addition, the frame format design is simple, and analysis of the second communication device and the first communication device is facilitated, so that transmission delay between the first communication device and the second communication device can be greatly reduced.

Fig. 7 is a signaling flowchart of a second embodiment of a channel sounding method provided in the present application. Different from the embodiment shown in fig. 5, the present embodiment relates to a specific process of feeding back channel information by the second communication device, that is, the present embodiment is directed to an alternative implementation manner of S107 and S108 in fig. 5. S107 in fig. 5 described above may be replaced with S201 described below, and S108 may be replaced with S202 described below. As shown in fig. 7, the method includes:

s201: and at least one second communication device in the second communication device group feeds back channel information to at least one first communication device in the first communication device group according to the identification arrangement sequence of the first communication device in the first communication device group.

S202: at least one first communication device in the first communication device group receives channel information fed back by at least one second communication device according to the identification arrangement sequence of the first communication devices in the first communication device group.

In this embodiment, the second communication device in the second communication device group may obtain the identifier permutation sequence of the first communication device in the first communication device group through the identifier list field of the first communication device in the NDPA frame. Therefore, when at least one second communication device in the second communication device group feeds back the corresponding channel information after receiving the trigger frame, the at least one second communication device in the second communication device group may feed back according to the identifier arrangement order of the first communication device.

Continuing with the frame interaction flow shown in fig. 6b as an example, assuming that the first communication device group includes AP1 and AP2, and the second communication device group includes STA1 and STA2, and it is assumed that AP1 sends a trigger frame having the structure shown in fig. 5d, where the trigger frame includes STA1 info and STA2 info, and the order of feedback indication information in STA1 info and STA2 info is feedback indication information 1 — feedback indication information 2, where the first communication device corresponding to the feedback indication information 1 is AP1, the second communication device corresponding to the feedback indication information 2 is AP2, and it is known that the target communication device selected by AP1 is STA1 and STA2 according to the content of the trigger frame. Therefore, both STA1 and STA2 have to feed back channel information.

Taking STA1 as an example, the channel information generated by STA1 according to the trigger frame includes channel information between STA1 and AP1 and channel information between STA1 and AP 2. If the order of the identities of the AP1 and AP2 in the identity list field of the first group of communication devices in the NDPA frame is: AP1 is in front, AP2 is behind, and STA1 may preferentially feed back channel information between STA1 and AP1 and then feed back channel information between STA1 and AP2 when feeding back channel information. It should be noted that, when the STA is required to feed back the channel state information of multiple APs, the STA needs a larger communication resource and a longer processing time by using the channel information feedback method in the embodiment of fig. 5; if the STA resources are limited and it is desired to shorten the processing time, the sequential feedback method described in the embodiment of fig. 7 may be adopted. Therefore, in this embodiment, the STA can perform feedback according to the identifier arrangement sequence of the APs, which is beneficial for the STA to obtain channel information in time, and greatly reduces the processing complexity of simultaneously feeding back the channel information between one STA and a plurality of APs. For the case that the STA2 feeds back the channel information, it is similar to the feedback of the STA1 and is not described herein again.

It should be noted that, when feeding back the channel information, whether the STA1 and the STA2 feed back the channel information at the same time or not is scheduled by the AP sending the trigger frame, that is, the STA1 and the STA2 may feed back the channel information at the same time, or the STA1 feeds back the channel information first, and the STA2 feeds back the channel information later.

On the other hand, for the STA to feed back the channel information, taking STA1 as an example, assuming that the feedback capability of STA1 is insufficient, but STA1 is required by AP1 to feed back the channel information between STA1 and multiple APs (as shown in the example shown in fig. 6b, STA1 is required by AP1 to feed back the channel information between STA1-AP1 and STA1-AP 2), STA1 preferentially feeds back the channel information between STA1 and the AP which transmits the trigger frame during feedback.

According to the channel detection method, the channel information is fed back to the at least one first communication device in the first communication device group through the at least one second communication device in the second communication device group according to the identification arrangement sequence of the first communication device in the first communication device group, so that the STA can obtain the channel information in time, and the processing complexity of feeding back the channel information between the STA and a plurality of APs at the same time is greatly reduced.

Fig. 8 is a signaling flowchart of a third embodiment of a channel sounding method provided in the present application. The present embodiment relates to a specific process in which after a certain first communication device in a first communication device group sends a trigger frame, an opportunity to send the trigger frame is transferred to another first communication device, so that the other first communication device can obtain an opportunity to request channel information from a second communication device. On the basis of the above embodiment, further, the method may further include the steps of:

s301: at least one first communication device in a first communication device group sends a transmission opportunity transfer frame to the next first communication device according to the identification arrangement sequence of the first communication devices in the first communication device group; and the transmission opportunity transfer frame is used for indicating the next first communication equipment to send a trigger frame to at least one second communication equipment according to the identifier arranging sequence.

Optionally, in this embodiment, each first communication device in the first communication device group may send a trigger frame to at least one second communication device in the second communication device group, and only the sending time and the sending sequence are different. After a first communication device sends a trigger frame, optionally, the first communication device may send a transmission opportunity transfer frame to a next first communication device after receiving complete channel information required by the first communication device itself; the first communication device may transmit the transmission opportunity transfer frame to the next first communication device after receiving the partial channel information.

Referring to fig. 9, a third schematic diagram of a frame interaction flow of channel sounding is shown, in fig. 9, a first communication device group includes AP1, AP2, and AP3, and a second communication device group includes STA1 and STA 2. First, the AP1, the AP2, and the AP3 in the first communication device group transmit NDPs in the order of the AP ID list in the NDPA frame, that is, the AP1 transmits NDP1 first, then the AP2 transmits NDP2, and then the AP3 transmits NDP 3. Then, the first communication device in the first communication device group may transmit the trigger frame (BRP trigger) in the order of the AP ID list, i.e., the AP1 transmits the trigger frame first. Assume that a trigger frame sent by the AP1 includes STA1 info and STA2 info, feedback indication information in the STA1 info and STA2 info are both feedback indication information 1, a first communication device corresponding to the feedback indication information 1 is the AP1, and STA1 info and STA2 info included in the trigger frame indicate that target communication devices selected by the AP1 are STA1 and STA 2. Therefore, both STA1 and STA2 need to feed back channel information with AP 1. Alternatively, when feeding back the channel information, the STA1 and the STA2 may feed back the channel information in a multicast or broadcast manner.

Alternatively, after the AP1 successfully receives the channel information fed back by the STA1 and the STA2, the AP1 may send a transmission opportunity Transfer frame (TXOP Transfer) to the AP 2.

S302: and the next first communication equipment transmits a trigger frame to at least one second communication equipment in the second communication equipment group according to the transmission opportunity transfer frame so as to acquire channel information between the at least one second communication equipment and the at least one first communication equipment.

Specifically, continuing with the frame interaction procedure shown in fig. 9 as an example, when the AP2 receives the transmission opportunity transfer frame, the AP2 sends a trigger frame to the SAT1 and the STA2 to acquire channel information between the STA1 and the STA2 and at least one of the AP1, the AP2, and the AP 3.

Optionally, when the STA1 and the STA2 feed back channel information according to the trigger frame sent by the AP1, both the AP2 and the AP3 may listen to the channel information, so as to obtain channel information between the STA1 and the STA2 and themselves; of course, AP2 and AP3 may not listen.

When the AP2 listens to the channel information fed back by the STA1 and the STA2 according to the trigger frame sent by the AP1, the AP2 and the AP2 may acquire partial channel information between the STA1 and the STA2 and themselves, and at this time, the trigger frame sent by the AP2 may be directed to an STA corresponding to the partial channel information that is not listened to, for example, if the AP2 listens to the channel information fed back by the STA1 and the STA2 according to the trigger frame sent by the AP1, the AP2 knows the channel information between the STA1 and the AP1, between the STA1 and the AP1, and does not listen to the channel information between the STA1 and the AP1, and at this time, the trigger frame sent by the AP1 includes the STA1 info to acquire the channel information between the STA1 and the AP 1. When the AP2 sends a trigger frame once, and finds that the STA2 only feeds back a part of the fragments of the channel information in the channel information, the AP2 sends the trigger frame again to obtain the remaining fragments of the channel information between the AP2 and the STA 2.

When the AP2 does not listen to the channel information fed back by STA1 and STA2 according to the trigger frame sent by AP1, the trigger frame sent by AP2 includes STA1 info and STA2 info.

S303: the next first communication device judges whether the next first communication device is the last first communication device in the identifier arrangement sequence; if not, S304 is executed, and if yes, S305 is executed.

S304: the next first communication device continues to transmit the transmission opportunity transfer frame to another first communication device adjacent to the next first communication device in the first communication device group in the order of the identification.

Optionally, after the AP2 successfully receives the required channel information, the AP2 determines whether it is the last first communication device through the AP ID list in the received NDPA frame, if not, the AP2 may send a transmission opportunity transfer frame to the AP3, and after the AP3 receives the transmission opportunity transfer frame, the above-mentioned processes of S302 and S303 are also performed.

S305: and the next first communication equipment sends a transmission opportunity returning frame to the main communication equipment in the first communication equipment group, wherein the transmission opportunity returning frame is used for indicating the main communication equipment that the first communication equipment in the first communication equipment group successfully receives the required channel information.

Specifically, when the AP3 determines that the first communication device itself is the last first communication device according to the received NDPA frame, after the AP3 successfully receives the channel information required by itself, the AP3 may send a transmission opportunity return frame to the first communication device that sends the NDPA frame in the first communication device group, and optionally, the AP3 may send a transmission opportunity return frame (TXOP return) to a master communication device (assumed to be the AP1) in the first communication device group. After the primary communication device receives the transmission opportunity return frame, it is known that all the first communication devices in the first communication device group successfully receive the required channel information, and then the primary communication device may start initialization (initialization) multi-cell joint transmission.

Optionally, the TXOP transfer and TXOP return may be a simple control frame or an Action frame, and only need to inform that its function is TXOP transfer or TXOP return through the type and subtype of the MAC frame or through the function field in the frame body. Optionally, Duration may be used to indicate the remaining TXOP Duration, and TA and RA may be used to indicate the initiator and the receiver of the TXOP transfer or return.

According to the channel detection method provided by the application, after a certain first communication device in a first communication device group sends a trigger frame, the first communication device sends a transmission opportunity transfer frame to the next first communication device according to an identification list field set by first communication in an NDPA frame, so that the opportunity of sending the trigger frame is transferred to the next first communication device, other first communication devices can obtain the opportunity of asking for channel information from at least one second communication device, the integrity of channel information feedback is improved, and the condition that channel information is not completely obtained is avoided.

Fig. 10 is a flowchart illustrating a fourth embodiment of a channel sounding method provided in the present application. The present embodiment relates to a processing procedure when the next first communication device cannot successfully acquire channel information all the time after the next first communication device receives a transmission opportunity transfer frame and sends a trigger frame. On the basis of the above embodiment, after the next first communication device receives the transmission opportunity transfer frame, the method may further include the steps of:

s401: and if the next first communication device sends a trigger frame meeting a preset condition, the next first communication device sends a failure frame to the main communication device for informing the main communication device that the next first communication device cannot successfully receive the channel information fed back by the at least one second communication device.

S402: and the main communication device or the next first communication device sends the transmission opportunity transfer frame to another first communication device which is positioned behind the next first communication device and adjacent to the next first communication device according to the identification arrangement sequence.

Specifically, referring to the frame interaction flow diagram of channel sounding shown in fig. 11, assuming that the next first communication device is AP2, when the number of times that the AP2 sends the trigger frame reaches a first threshold and/or the total sending time that the AP2 sends the trigger frame reaches a second preset threshold, the AP2 sends a failure frame, such as a BF Report failure frame, to the AP1 (the AP1 is set as the main communication device). After the AP1 receives the channel information failure frame, the AP1 knows that the AP2 cannot successfully receive the channel information, and then the AP1 or the AP2 sends a transmission opportunity transfer frame to the AP3 according to the identifier permutation order of the first communication device in the NDPA frame (assuming that the identifier permutation order of the first communication device in the NDPA frame is AP1-AP2-AP3), where the AP3 is another first communication device located behind the AP2 and adjacent to the AP2, so that the AP3 sends a trigger frame to at least one second communication device to obtain the channel information between the at least one second communication device and the at least one first communication device. It should be noted that the "adjacent" in the "another first communication apparatus adjacent to the next first communication apparatus" referred to in the present embodiment refers to another first communication apparatus adjacent to the "next first communication apparatus" after the "next first communication apparatus" in the identification sorting order of the first communication apparatus in the NDPA frame.

Optionally, when the main communication device (AP1) knows that the AP2 cannot successfully acquire the channel information, the AP1 may forward the acquired channel information between the at least one first communication device and the at least one second communication device to the AP2 through a wired or other wireless frequency band, or when performing joint transmission, different APs 2 participate together.

In the channel detection method provided by the present application, after a first communication device in a first communication device group sends a transmission opportunity transfer frame to a next first communication device, the next first communication device sends a trigger frame to at least one second communication device according to the transmission opportunity transfer frame, when the trigger frame sent by the next first communication device satisfies a preset condition, the next first communication device actively sends a failure frame to a main communication device in the first communication device group for notifying the main communication device that the next first communication device cannot successfully receive channel information fed back by at least one second communication device, so that the main communication device or the next first communication device sends the transmission opportunity transfer frame to another first communication device located behind and adjacent to the next first communication device according to the above identification arrangement order, the opportunity of asking for the channel information is transferred to other first communication equipment in time, so that when a certain AP cannot acquire the channel information, the acquisition of the channel information by other APs and the subsequent joint transmission of multiple APs cannot be influenced, and the efficiency of acquiring the channel information is greatly improved.

Fig. 12 is a signaling flowchart of a fifth embodiment of a channel sounding method provided in the present application. Different from the embodiment shown in fig. 8, in this embodiment, it is the primary communication device in the first communication device group that sends the trigger frame to at least one second communication device in the second communication device group, and the other secondary communication devices in the first communication device group do not send the trigger frame. The embodiment relates to a specific process for acquiring the receiving condition of the channel information of other auxiliary communication devices by the main communication device. After S104 shown in fig. 5, the method may further include the steps of:

s501: a master communication device in a first communication device group sends at least one trigger frame to at least one second communication device; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

S502: at least one second communication device in the second communication device group receives at least one trigger frame sent by the main communication device in the first communication device group.

Specifically, the primary communication device is any one of the first communication devices in the first communication device group, and the remaining other first communication devices are the secondary communication devices. In this embodiment, the trigger frame is uniformly sent by the primary communication device, and the other secondary communication devices do not send the trigger frame, and acquire the channel information fed back by the at least one second communication device in an interception manner.

Referring to fig. 13, a frame interaction flow diagram of channel sounding is shown in fig. 13, where the first communication device group includes AP1, AP2, and AP3, and the second communication device group includes STA1 and STA 2. First, the AP1, the AP2, and the AP3 in the first communication device group transmit NDPs in the order of the AP ID list in the NDPA frame, that is, the AP1 transmits NDP1 first, then the AP2 transmits NDP2, and then the AP3 transmits NDP 3. Then, the master communication device (AP1) in the first communication device group sends a Trigger frame (BRP Trigger), where the Trigger frame includes STA1 info and STA2 info, an order of the feedback indication information in the STA1 info is feedback indication information 1 — feedback indication information 2 — feedback indication information 3, and an order of the feedback indication information in the STA2 info is feedback indication information 1 — feedback indication information 2, where the first communication device corresponding to the feedback indication information 1 is AP1, the first communication device corresponding to the feedback indication information 2 is AP2, and the first communication device corresponding to the feedback indication information 3 is AP 3. STA1 info and STA2 info contained in the trigger frame indicate that the target communication devices selected by AP1 are STA1 and STA 2. Therefore, both STA1 and STA2 need to feed back channel information with AP 1. Alternatively, when feeding back the channel information, the STA1 and the STA2 may feed back the channel information in a multicast or broadcast manner.

In addition, channel information fed back by STA1 includes channel information between STA1-AP1, STA1-AP2 and STA1-AP3, i.e., BFR (AP1&2&3) in fig. 13, and channel information fed back by STA2 includes channel information between STA2-AP1 and STA2-AP2, i.e., BFR (AP1&2) in fig. 13.

S503: and the primary communication equipment sends a retransmission bitmap trigger frame to the secondary communication equipment, wherein the retransmission bitmap trigger frame is used for requesting the secondary communication equipment for the receiving condition of the channel information fed back by the secondary communication equipment aiming at least one second communication equipment.

S504: and the auxiliary communication equipment sends a retransmission bit map frame to the main communication equipment, wherein the retransmission bit map frame carries the receiving condition of the channel information fed back by the auxiliary communication equipment aiming at least one second communication equipment.

S505: and the main communication equipment receives the retransmission bitmap frame sent by the auxiliary communication equipment.

Specifically, in this embodiment, since the opportunities for retrieving channel information are integrated in the AP1, the other secondary APs (AP2 and AP3) listen to the channel information fed back by the STA1 and STA2 in a listening manner, so as to obtain the channel information required by themselves. When the AP1 wants to acquire the reception condition of the channel information of other secondary APs, the AP1 sends a Retransmission Bitmap trigger frame (Retransmission Bitmap trigger, referred to as ReTx Bitmap trigger) to the other secondary APs. Optionally, in this embodiment, the primary communication device and the secondary communication device may transmit the ReTx Bitmap trigger frame and the ReTx Bitmap frame in a wired or wireless manner. Optionally, the retransmitting bitmap trigger frame may include: a frame type identification and information of at least one secondary communication device. For example, the frame format of the ReTx Bitmap trigger may be as shown in fig. 5 j.

In fig. 5j, Trigger Type is a frame Type identifier for identifying that the frame is a retransmission bitmap Trigger frame, an AP ID included in STA Info is for indicating that the AP feeds back a reception situation of channel information fed back by an STA in the STA Info, and RU allocation is resource unit configuration.

When the secondary AP receives the ReTx Bitmap trigger, the secondary AP transmits a retransmission Bitmap frame (ReTx Bitmap) to the primary communication device, where the retransmission Bitmap frame carries a reception condition of channel information fed back by the secondary AP for at least one STA. When the AP1 knows that neither AP2 nor AP3 has completely received the required channel information, the AP1 sends corresponding trigger frames to STA1 and STA2 again to instruct STA1 and STA2 to continue to feed back the fragments of the remaining channel information in the channel information. Optionally, the retransmitting bitmap frame includes: the secondary communication device comprises an identification field of at least one second communication device and a feedback fragment retransmission bitmap field corresponding to the at least one second communication device, wherein one feedback fragment retransmission bitmap field is used for indicating the receiving condition of the channel information fed back by the secondary communication device aiming at one second communication device. Illustratively, the structure of the retransmitted bitmap frame can be seen in fig. 5 k.

In fig. 5k, the AID of STA is an identification field of the second communication device, the Feedback Segment retransmission bitmap is a Feedback Segment retransmission bitmap field corresponding to the second communication device, and one Feedback Segment retransmission bitmap field is used to indicate a receiving situation of channel information fed back by the secondary communication device for one second communication device. The Preferred RU/MCS for CSI/CQI feedback indicates Resource Units (RUs) and Modulation and Coding Schemes (MCS) that the AP intends to use when the AP wants to receive channel information sent by the STA, that is, other secondary APs schedule the STA to send channel information in the proposed RU and adopt the proposed MCS when the AP1 recommends to request channel information from at least one STA next time.

According to the channel detection method, the main communication equipment in the first communication equipment group sends the retransmission bitmap trigger frame through the auxiliary communication equipment to request to acquire the receiving condition of the channel information fed back by the auxiliary communication equipment aiming at the at least one second communication equipment, and the receiving condition of the channel information fed back by the auxiliary communication equipment aiming at the at least one second communication equipment is acquired according to the received retransmission bitmap frame sent by the auxiliary communication equipment, so that the condition that the time delay for acquiring the channel information is increased due to non-intercommunication between the first communication equipment is avoided, and the feedback efficiency of the channel information is further improved.

Fig. 14 is a schematic structural diagram of a first embodiment of a communication device provided in the present application. The communication device is the first communication device involved in the above method embodiment, and is applicable to a communication system including a first communication device group and a second communication device group participating in channel sounding, where the first communication device group includes at least one first communication device, and the second communication device group includes at least one second communication device; the first communication device includes: a transmitting module 11 and a receiving module 12.

The sending module 11 is configured to send a null data packet announcement, NDPA frame, where the NDPA frame is used to indicate a first communication device group and a second communication device group participating in channel sounding, where the channel sounding includes sounding channel information of a channel between at least one first communication device and at least one second communication device;

the sending module 11 is further configured to send a Null Data Packet (NDP) to a second communication device in the second communication device group, and send a trigger frame to at least one second communication device in the second communication device group, where the NDP is used to instruct the second communication device to probe channel information with at least one first communication device; the trigger frame is used for triggering at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

the receiving module 12 is configured to receive channel information fed back by at least one second communication device.

Optionally, the first communication device is a master communication device;

the NDPA frame sent by the sending module 11 is further configured to indicate an identifier permutation order of a first communication device in the first communication device group and a channel sounding indication parameter required when at least one second communication device acquires channel information.

Optionally, the receiving module 12 is specifically configured to receive channel information fed back by at least one second communication device according to the identifier ranking order of the first communication devices in the first communication device group.

Optionally, the sending module 11 is further configured to send a transmission opportunity transfer frame to a next first communication device according to the identifier ranking order of the first communication devices in the first communication device group; and the transmission opportunity transfer frame is used for indicating the next first communication equipment to send a trigger frame to at least one second communication equipment according to the identifier arranging sequence.

Optionally, if the next first communication device is the last first communication device in the identifier permutation order,

the sending module 11 is further configured to send a transmission opportunity returning frame to the master communication device in the first communication device group, where the transmission opportunity returning frame is used to indicate, to the master communication device, that all the first communication devices in the first communication device group successfully receive the required channel information.

Optionally, if the trigger frame sent by the next first communication device satisfies the preset condition,

the sending module 11 is further configured to send a failure frame to the primary communication device, where the failure frame is used to notify the primary communication device that the next first communication device cannot successfully receive the channel information fed back by the at least one second communication device;

wherein the preset conditions include: the sending frequency of the trigger frame sent by the sending module 11 reaches at least one of a first preset threshold value and a second preset threshold value, where the total sending time of the trigger frame sent by the sending module 11 reaches the first preset threshold value.

Optionally, the sending module 11 is further configured to send the transmission opportunity transfer frame to another first communication device that is located after the next first communication device and adjacent to the next first communication device according to the identifier ranking order.

Optionally, if the sending module 11 is a module in the main communication device,

the sending module 11 is specifically configured to send at least one trigger frame to at least one second communication device; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

Optionally, the sending module 11 is further configured to send a retransmission bitmap trigger frame to the secondary communication device, where the retransmission bitmap trigger frame is used to request, to the secondary communication device, a receiving condition of channel information fed back by the secondary communication device for at least one second communication device;

the receiving module 12 is further configured to receive a retransmitted bitmap frame sent by the secondary communication device, where the retransmitted bitmap frame carries a receiving condition of channel information fed back by the secondary communication device for at least one second communication device.

Optionally, the retransmitting the bitmap trigger frame includes: information of a frame type identification and at least one secondary communication device;

the retransmission bitmap frame includes: the secondary communication device comprises an identification field of at least one second communication device and a feedback fragment retransmission bitmap field corresponding to the at least one second communication device, wherein one feedback fragment retransmission bitmap field is used for indicating the receiving condition of the channel information fed back by the secondary communication device aiming at one second communication device.

Optionally, the sending module 11 is specifically configured to send a first NDPA frame to at least one second communication device, where the first NDPA frame includes: a first identifier, a number of first communication devices in the first communication device group field, an identifier list field of first communication devices in the first communication device group, a number of second communication devices in a second communication device group field, and an information field of each second communication device; the identification list field is used for representing an identification arrangement order of first communication equipment in the first communication equipment group, the information field of the second communication equipment is used for representing identification of the second communication equipment and the channel sounding indication parameter, and the first identification is used for representing the type of the first NDPA frame;

the sending module 11 is further configured to send a second NDPA frame to at least one second communication device, where the second NDPA frame includes: a second identifier, a number field of second communication devices in the second communication device group, and an information field of each second communication device, where the second identifier is used to characterize a type of the second NDPA frame, and a length of the first NDPA frame is greater than a length of the second NDPA frame.

Optionally, the NDPA frame includes: a number of first communication devices in the first communication device group field, an identification list field of first communication devices in the first communication device group field, a number of second communication devices in a second communication device group field, and an information field of each second communication device;

Optionally, the trigger frame includes information of at least one target communication device;

the information of the target communication device is used for instructing the target communication device to acquire channel information between the target communication device and part or all of devices in the first communication device group; the target communication device is a second communication device selected by the first communication device sending the trigger frame.

Optionally, the information of the target communication device includes an identifier of the target communication device and at least one piece of feedback indication information, where one piece of feedback indication information corresponds to one first communication device;

the feedback indication information is used to indicate to the target communication device that the first communication device that sent the trigger frame needs to acquire channel information between the target communication device and the first communication device corresponding to the feedback indication information.

Optionally, in the information of the target communication device, an order of each piece of feedback indication information in the at least one piece of feedback indication information is the same as an identifier arrangement order of the first communication device in the first communication device group.

Optionally, the information of the target communication device further includes: and the identifier of the first communication device corresponding to the feedback indication information is adjacent to the identifier of the first communication device corresponding to the feedback indication information.

Optionally, the channel information is carried in a beamforming report.

In one possible implementation, the beamforming report includes: a frame identification, at least one first multiple-input multiple-output, MIMO, control field, and channel information associated with the first MIMO control field; the channel information associated with the first MIMO control field is the channel information between the target communication device and the first communication device associated with the first MIMO control field; wherein a first MIMO control field is associated with a first communication device corresponding to a feedback indication information;

the first MIMO control field comprises: an identifier of the first communication device related to the first MIMO control field, an identifier of the first communication device corresponding to a last feedback indication information of the at least one feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device participating in channel sounding.

In another possible implementation, the beamforming report includes: frame identification, a second multiple-input multiple-output (MIMO) control field and channel information between the target communication device and the first communication device corresponding to each piece of feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device;

wherein the second MIMO control field comprises: at least one first MIMO control field, one first MIMO control field associated with a first communication device corresponding to one feedback indication information, the first MIMO control field comprising: an identity of the first communication device related to the first MIMO control field, an identity of the first communication device corresponding to a last feedback indication information of the at least one feedback indication information.

In yet another possible implementation, the beamforming report includes: frame identification, a third MIMO control field, and channel information between the target communication device and the first communication device corresponding to each feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device;

wherein the third MIMO control field comprises: a common part of the target communication device when feeding back channel information between first communication devices corresponding to the at least one piece of feedback indication information, and a fragmentation indication field corresponding to the first communication device corresponding to each piece of feedback indication information; the fragmentation indication field is used for indicating the number of the residual channel information fragmentation which is not fed back by the target communication equipment;

in the third MIMO control field, the number of repetitions of the common part is zero, and the common part includes a number field of the first communication devices corresponding to the at least one feedback indication information and an identifier permutation order field of the first communication devices corresponding to the at least one feedback indication information.

Optionally, the feedback indication information is further configured to indicate, to the target communication device, that the first communication device that sends the trigger frame needs to acquire the fragmentation information of the channel information between the target communication device and the first communication device corresponding to the feedback indication information.

The communication device provided in the embodiment of the present application may perform the process performed by the first communication device in the above method embodiments, and the implementation principle and the technical effect are similar, which are not described herein again.

Fig. 15 is a schematic structural diagram of a second communication device according to an embodiment of the present application. The communication device is a second communication device and is applicable to a communication system comprising a first communication device group and a second communication device group which participate in channel detection, wherein the first communication device group comprises at least one first communication device, and the second communication device group comprises at least one second communication device; the second communication device includes: a receiving module 21, a channel detecting module 22 and a transmitting module 23;

the receiving module 21 is configured to receive a null data packet announcement, NDPA, frame sent by at least one first communication device in the first communication device group, where the NDPA frame is used to indicate a first communication device group and a second communication device group participating in channel sounding, where the channel sounding includes sounding channel information of a channel between the at least one first communication device and the at least one second communication device;

the receiving module 21 is further configured to receive a null data packet NDP sent by each first communication device in the first communication device group;

the channel sounding module 22 is configured to sound channel information between the second communication device and at least one first communication device according to the NDP;

the receiving module 21 is further configured to receive a trigger frame sent by at least one first communication device in the first communication device group, where the trigger frame is used to trigger at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

the sending module 23 is configured to feed back channel information to at least one first communication device in the first communication device group.

Optionally, the receiving module 21 is specifically configured to receive an NDPA frame sent by a master communication device in the first communication device group, where the NDPA frame is further configured to indicate an identifier permutation order of the first communication device in the first communication device group and a channel sounding indication parameter required when at least one second communication device acquires channel information.

Optionally, the sending module 23 is specifically configured to feed back channel information to at least one first communication device in the first communication device group according to the identifier ranking order of the first communication devices in the first communication device group.

Optionally, the receiving module 21 is specifically configured to receive at least one trigger frame sent by a master communication device in the first communication device group; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

Optionally, the receiving module 21 is specifically configured to receive a first NDPA frame sent by a primary communication device in the first communication device group, and receive a second NDPA frame sent by a secondary communication device in the first communication device group;

the first NDPA frame includes: a first identifier, a number of first communication devices in the first communication device group field, an identifier list field of first communication devices in the first communication device group, a number of second communication devices in a second communication device group field, and an information field of each second communication device; the identification list field is used for representing an identification arrangement order of first communication equipment in the first communication equipment group, the information field of the second communication equipment is used for representing identification of the second communication equipment and the channel sounding indication parameter, and the first identification is used for representing the type of the first NDPA frame;

the second NDPA frame includes: a second identifier, a number field of second communication devices in the second communication device group, and an information field of each second communication device, where the second identifier is used to characterize a type of the second NDPA frame, and a length of the first NDPA frame is greater than a length of the second NDPA frame.

Optionally, the channel information is carried in a beamforming report.

Optionally, the beamforming report includes: a frame identification, at least one first multiple-input multiple-output, MIMO, control field, and channel information associated with the first MIMO control field; the channel information associated with the first MIMO control field is the channel information between the target communication device and the first communication device associated with the first MIMO control field; wherein a first MIMO control field is associated with a first communication device corresponding to a feedback indication information;

Optionally, the beamforming report includes: frame identification, a second multiple-input multiple-output (MIMO) control field and channel information between the target communication device and the first communication device corresponding to each piece of feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device;

Optionally, the beamforming report includes: frame identification, a third MIMO control field, and channel information between the target communication device and the first communication device corresponding to each feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device;

The communication device provided in the embodiment of the present application may perform the process performed by the second communication device in the above method embodiments, and the implementation principle and the technical effect are similar, which are not described herein again.

Fig. 16 is a schematic structural diagram of a third embodiment of a communication device provided in the present application. The communication device is the first communication device involved in the above method embodiment, and is applicable to a communication system including a first communication device group and a second communication device group participating in channel sounding, where the first communication device group includes at least one first communication device, and the second communication device group includes at least one second communication device. As shown in fig. 16, the first communication device may include a receiver 31, a memory 32, a processor 33, at least one communication bus 34, and a transmitter 35. The communication bus 34 is used to realize communication connections between the elements. The memory 32 may comprise a high speed RAM memory, and may also include a non-volatile memory NVM, such as at least one disk memory, in which various programs may be stored for performing various processing functions and implementing the method steps of the present embodiment. In this embodiment, the transmitter 35 may be a radio frequency processing module or a baseband processing module in the first communication device, the receiver 31 may also be a radio frequency processing module or a baseband processing module in the first communication device, the transmitter 35 and the receiver 31 may be integrated together to be implemented as a transceiver, both the transmitter 35 and the receiver 31 may be coupled to the processor 33, and may implement the receiving or transmitting actions under the instruction or control of the processor 33.

In this embodiment, the transmitter 35 is configured to transmit a null data packet announcement, NDPA frame, where the NDPA frame is used to indicate a first communication device group and a second communication device group participating in channel sounding, where the channel sounding includes sounding channel information of a channel between at least one first communication device and at least one second communication device;

the transmitter 35 is further configured to transmit a Null Data Packet (NDP) to a second communication device in the second communication device group, and transmit a trigger frame to at least one second communication device in the second communication device group, where the NDP is used to instruct the second communication device to probe channel information with at least one first communication device; the trigger frame is used for triggering at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

the receiver 31 is configured to receive channel information fed back by at least one second communication device.

Optionally, the first communication device is a master communication device;

the NDPA frame sent by the transmitter 35 is further configured to indicate an identifier permutation order of the first communication devices in the first communication device group and a channel sounding indication parameter required when the at least one second communication device acquires channel information.

Optionally, the receiver 31 is specifically configured to receive channel information fed back by at least one second communication device according to the identification ranking order of the first communication devices in the first communication device group.

Optionally, the transmitter 35 is further configured to transmit a transmission opportunity transfer frame to a next first communication device according to the identification ranking order of the first communication devices in the first communication device group; and the transmission opportunity transfer frame is used for indicating the next first communication equipment to send a trigger frame to at least one second communication equipment according to the identifier arranging sequence.

the transmitter 35 is further configured to transmit a transmission opportunity returning frame to the master communication device in the first communication device group, where the transmission opportunity returning frame is used to indicate to the master communication device that the first communication devices in the first communication device group all successfully receive the required channel information.

the transmitter 35 is further configured to transmit a failure frame to the primary communication device, so as to notify the primary communication device that the next first communication device cannot successfully receive the channel information fed back by the at least one second communication device;

wherein the preset conditions include: at least one of the number of times that the trigger frame is transmitted by the transmitter 35 reaches a first preset threshold value and the total transmission time that the trigger frame is transmitted by the transmitter 35 reaches a second preset threshold value.

Optionally, the transmitter 35 is further configured to transmit the transmission opportunity transfer frame to another first communication device that is located after the next first communication device and adjacent to the next first communication device according to the identification ranking order.

Alternatively, if the transmitter 35 is a component in the primary communication device,

the transmitter 35 is specifically configured to transmit at least one trigger frame to at least one second communication device; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

Optionally, the transmitter 35 is further configured to transmit a retransmission bitmap trigger frame to the secondary communication device, where the retransmission bitmap trigger frame is used to request, from the secondary communication device, a receiving condition of channel information fed back by the secondary communication device for at least one second communication device;

the receiver 31 is further configured to receive a retransmission bitmap frame sent by the secondary communication device, where the retransmission bitmap frame carries a receiving condition of channel information fed back by the secondary communication device for at least one second communication device.

Optionally, the transmitter 35 is specifically configured to transmit a first NDPA frame to at least one second communication device, where the first NDPA frame includes: a first identifier, a number of first communication devices in the first communication device group field, an identifier list field of first communication devices in the first communication device group, a number of second communication devices in a second communication device group field, and an information field of each second communication device; the identification list field is used for representing an identification arrangement order of first communication equipment in the first communication equipment group, the information field of the second communication equipment is used for representing identification of the second communication equipment and the channel sounding indication parameter, and the first identification is used for representing the type of the first NDPA frame;

the transmitter 35 is further configured to transmit a second NDPA frame to at least one second communication device, where the second NDPA frame includes: a second identifier, a number field of second communication devices in the second communication device group, and an information field of each second communication device, where the second identifier is used to characterize a type of the second NDPA frame, and a length of the first NDPA frame is greater than a length of the second NDPA frame.

Optionally, the channel information is carried in a beamforming report.

Fig. 17 is a schematic structural diagram of a fourth embodiment of a communication device provided in the present application. The communication device is a second communication device and is applicable to a communication system comprising a first communication device group and a second communication device group which participate in channel detection, wherein the first communication device group comprises at least one first communication device, and the second communication device group comprises at least one second communication device. As shown in fig. 17, the second communication device may include a receiver 41, a memory 42, a processor 43, at least one communication bus 44, and a transmitter 45. The communication bus 44 is used to enable communication connections between the elements. The memory 42 may comprise a high speed RAM memory and may also include a non-volatile memory NVM, such as at least one disk memory, in which various programs may be stored for performing various processing functions and implementing the method steps of the present embodiment. In this embodiment, the transmitter 45 may be a radio frequency processing module or a baseband processing module in the first communication device, the receiver 41 may also be a radio frequency processing module or a baseband processing module in the first communication device, the transmitter 45 and the receiver 41 may be integrated together to be implemented as a transceiver, both the transmitter 45 and the receiver 41 may be coupled to the processor 43, and may implement the actions of receiving or transmitting under the instruction or control of the processor 43.

In this embodiment, the receiver 41 is configured to receive a null data packet announcement, NDPA, frame sent by at least one first communication device in the first communication device group, where the NDPA frame is used to indicate a first communication device group and a second communication device group participating in channel sounding, where the channel sounding includes sounding channel information of a channel between the at least one first communication device and the at least one second communication device;

the receiver 41 is further configured to receive a null data packet NDP sent by each first communication device in the first communication device group;

the processor configured to probe channel information between the second communication device and at least one first communication device according to the NDP;

the receiver 41 is further configured to receive a trigger frame sent by at least one first communication device in the first communication device group, where the trigger frame is used to trigger at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

the transmitter 45 is configured to feed back channel information to at least one first communication device in the first communication device group.

Optionally, the receiver 41 is specifically configured to receive an NDPA frame sent by a master communication device in the first communication device group, where the NDPA frame is further configured to indicate an identifier permutation order of the first communication devices in the first communication device group and a channel sounding indication parameter required when at least one second communication device acquires channel information.

Optionally, the transmitter 45 is specifically configured to feed back channel information to at least one first communication device in the first communication device group according to the identifier ranking order of the first communication devices in the first communication device group.

Optionally, the receiver 41 is specifically configured to receive at least one trigger frame sent by a master communication device in the first communication device group; and the auxiliary communication equipment in the first communication equipment group acquires the channel information fed back by at least one second communication equipment in an interception mode.

Optionally, the receiver 41 is specifically configured to receive a first NDPA frame sent by a primary communication device in the first communication device group, and receive a second NDPA frame sent by a secondary communication device in the first communication device group;

Optionally, the channel information is carried in a beamforming report.

The present application also provides a computer-readable storage medium having stored therein instructions, which, when run on a computer, cause the computer to perform the method performed by the first communication device in the above-described method embodiments.

The present application also provides a computer-readable storage medium having stored therein instructions, which, when run on a computer, cause the computer to perform the method performed by the second communication device in the above-described method embodiments.

Embodiments of the present application further provide a computer program product, which contains instructions, when the computer program is executed by a computer, the instructions cause the computer to perform the functions performed by the first communication device in the above method.

Embodiments of the present application further provide a computer program product, which contains instructions that, when executed by a computer, cause the computer to perform the functions performed by the second communication device in the above method.

All or part of the above embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using a software program, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions described in accordance with the embodiments of the application, in whole or in part, result when the computer program instructions are loaded and executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium. For example, the computer instructions may be transmitted from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, digital subscriber line DSL), or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium such as a floppy disk, a hard disk, a magnetic tape, an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk SSD), among others.

Claims

1. A method of channel sounding, adapted to a communication system including a first communication device group and a second communication device group participating in channel sounding, wherein the first communication device group includes at least one first communication device, wherein the second communication device group includes at least one second communication device, and wherein at least one second communication device in the second communication device group is not associated with at least one first communication device in the first communication device group; the method comprises the following steps:

at least one first communication device in the first communication device group sends a Null Data Packet Announcement (NDPA) frame, wherein the NDPA frame is used for indicating a first communication device group and a second communication device group which participate in channel sounding, and the channel sounding comprises channel information for sounding a channel between the at least one first communication device and the at least one second communication device;

each first communication device in the first communication device group sending a Null Data Packet (NDP) to a second communication device in the second communication device group, wherein the NDP is used for indicating the second communication device to probe channel information with at least one first communication device;

at least one first communication device in the first communication device group receives channel information fed back by at least one second communication device.

2. The method of claim 1, wherein the sending of the NDPA frame by at least one first communication device in the first communication device group comprises: at least one first communication device in the first communication device group sends an NDPA frame to a second communication device in the second communication group, wherein the second communication device in the second communication group comprises at least one second communication device which is not associated with the first communication device.

3. The method according to claim 1 or 2, wherein at least one first communication device of the first communication device group sends a trigger frame to at least one second communication device of the second communication device group, wherein the at least one second communication device comprises at least one second communication device unassociated with the first communication device.

4. The method according to any of claims 1-3, wherein the NDPA frame is used to indicate an identification ordering of first communication devices in the first communication device group and a channel sounding indication parameter required by at least one second communication device to acquire channel information.

5. The method according to any of claim 4, wherein each first communication device of the first communication device group sends a Null Data Packet (NDP) to a second communication device of the second communication device group, and specifically comprises: and each first communication device in the first communication device group respectively sends a Null Data Packet (NDP) to second communication devices in the second communication device group according to a first sequence, wherein the first sequence is determined based on the identification arrangement sequence.

6. The method of any of claims 1-5, wherein the NDPA frame comprises information common to at least two first communication devices of the first group of communication devices and information corresponding to each of the at least two first communication devices.

7. The method of claim 6, wherein the information common to the at least two first communication devices comprises: site identification information, partial bandwidth information, feedback type, grouping information of subcarriers and codebook size;

the information corresponding to each of the at least two first communication devices respectively comprises: and each first communication device corresponds to the column number of the channel information required to be acquired.

8. The method according to any of claims 1-7, wherein the trigger frame comprises information of at least one target communication device, the information of the target communication device instructing the target communication device to acquire channel information between the target communication device and some or all of the devices in the first communication device group; the target communication device is a second communication device selected by the first communication device sending the trigger frame.

9. The method of claim 8, wherein the information of the target communication device comprises an identifier of the target communication device and at least one piece of feedback indication information, one piece of the feedback indication information corresponding to one first communication device;

10. The method according to any of claims 1-9, wherein the channel information is carried in a beamforming report.

11. The method of claim 10, wherein the beamforming report comprises: a frame identification, at least one first multiple-input multiple-output, MIMO, control field, and channel information associated with the first MIMO control field; the channel information associated with the first MIMO control field is the channel information between the target communication device and the first communication device associated with the first MIMO control field; wherein one of the first MIMO control fields is associated with a first communication device corresponding to one of the feedback indication information;

the frame identification is used to characterize the beamforming report as a report containing channel information between the target communication device and at least one first communication device participating in channel sounding;

the first MIMO control field comprises: an identity of the first communication device related to the first MIMO control field, an identity of the first communication device corresponding to a last feedback indication information of the at least one feedback indication information.

12. The method of claim 10, wherein the beamforming report comprises: frame identification, a multiple-input multiple-output (MIMO) control field related to at least two first communication devices corresponding to the feedback indication information, and channel information between the target communication device and the first communication device corresponding to each feedback indication information;

the frame identification is used to characterize the beamforming report as a report containing channel information between the target communication device and at least two first communication devices.

13. A method of channel sounding, adapted to a communication system including a first communication device group and a second communication device group participating in channel sounding, wherein the first communication device group includes at least one first communication device, wherein the second communication device group includes at least one second communication device, and wherein at least one second communication device in the second communication device group is not associated with at least one first communication device in the first communication device group; the method comprises the following steps:

a second communication device in a second communication device group receives a null data packet declaration (NDPA) frame sent by at least one first communication device in the first communication device group, wherein the NDPA frame is used for indicating the first communication device group and the second communication device group which participate in channel detection, and the channel detection comprises channel information for detecting a channel between the at least one first communication device and the at least one second communication device;

a second communication device in the second communication device group receives a Null Data Packet (NDP) sent by each first communication device in the first communication device group, and detects channel information between the second communication device and at least one first communication device according to the NDP;

and at least one second communication device in the second communication device group feeds back channel information to at least one first communication device in the first communication device group.

14. The method of claim 13, wherein a second communication device of the second communication device group receives the NDPA frame sent by at least one first communication device of the first communication device group, and wherein the second communication device of the second communication device group comprises at least one second communication device unassociated with the first communication device.

15. The method according to claim 13 or 14, wherein the second communication device in the second communication device group receives the trigger frame sent by at least one first communication device in the first communication device group, and the at least one second communication device comprises at least one second communication device unassociated with the first communication device.

16. The method according to any of claims 13-15, wherein the NDPA frame is used to indicate an identification ranking of the first communication devices in the first communication device group and a channel sounding indication parameter required by the at least one second communication device to acquire the channel information.

17. The method of any of claims 13-16, wherein the NDPA frame comprises information common to at least two first communication devices of the first group of communication devices and information corresponding to each of the at least two first communication devices.

18. The method of claim 17, wherein the information common to the at least two first communication devices comprises: site identification information, partial bandwidth information, feedback type, grouping information of subcarriers and codebook size;

19. The method according to any of claims 13-17, wherein the trigger frame comprises information of at least one target communication device, the information of the target communication device instructing the target communication device to obtain channel information between the target communication device and some or all of the devices in the first communication device group; the target communication device is a second communication device selected by the first communication device sending the trigger frame.

20. The method of claim 19, wherein the information of the target communication device comprises an identifier of the target communication device and at least one feedback indication information, one feedback indication information corresponding to one first communication device;

21. The method according to any of claims 13-19, wherein the channel information is carried in a beamforming report.

22. The method of claim 21, wherein the beamforming report comprises: at least one first multiple-input multiple-output, MIMO, control field, and channel information associated with the first MIMO control field; the channel information associated with the first MIMO control field is the channel information between the target communication device and the first communication device associated with the first MIMO control field; wherein a first MIMO control field is associated with a first communication device corresponding to a feedback indication information;

the first MIMO control field comprises: an identity of the first communication device corresponding to a last feedback indication information of the at least one feedback indication information; the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least one first communication device participating in channel sounding.

23. The method of claim 21, wherein the beamforming report comprises: the Multiple Input Multiple Output (MIMO) control fields related to at least two first communication devices corresponding to the feedback indication information and channel information between the target communication device and the first communication device corresponding to each feedback indication information;

the frame identification is used to characterize the beamforming report as a report containing channel information between a target communication device and at least two first communication devices.

24. A communication device, wherein the communication device is a first communication device and is adapted to a communication system including a first communication device group and a second communication device group participating in channel sounding, wherein the first communication device group includes at least one first communication device, wherein the second communication device group includes at least one second communication device, and wherein at least one second communication device in the second communication device group is not associated with at least one first communication device in the first communication device group; the first communication device includes: a transmitting module and a receiving module;

the sending module is configured to send a null data packet announcement, NDPA, frame, where the NDPA frame is used to indicate a first communication device group and a second communication device group participating in channel sounding, where the channel sounding includes sounding channel information of a channel between at least one first communication device and at least one second communication device;

the sending module is further configured to send a Null Data Packet (NDP) to a second communication device in the second communication device group, and send a trigger frame to at least one second communication device in the second communication device group, where the NDP is used to indicate that the second communication device probes channel information with at least one first communication device; the trigger frame is used for triggering at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

the receiving module is configured to receive channel information fed back by at least one second communication device.

25. A communication device, wherein the communication device is a second communication device, and is adapted to a communication system including a first communication device group and a second communication device group participating in channel sounding, wherein the first communication device group includes at least one first communication device, wherein the second communication device group includes at least one second communication device, and wherein at least one second communication device in the second communication device group is not associated with at least one first communication device in the first communication device group; the second communication device includes: the system comprises a receiving module, a channel detection module and a sending module;

the receiving module is configured to receive a null data packet announcement, NDPA, frame sent by at least one first communication device in the first communication device group, where the NDPA frame is used to indicate a first communication device group and a second communication device group participating in channel sounding, where the channel sounding includes sounding channel information of a channel between the at least one first communication device and the at least one second communication device;

the receiving module is further configured to receive a null data packet NDP sent by each first communication device in the first communication device group;

the channel detection module is configured to detect channel information between the second communication device and at least one first communication device according to the NDP;

the receiving module is further configured to receive a trigger frame sent by at least one first communication device in the first communication device group, where the trigger frame is used to trigger at least one second communication device to feed back channel information between the at least one second communication device and the at least one first communication device;

the sending module is configured to feed back channel information to at least one first communication device in the first communication device group.

26. A computer-readable storage medium having stored therein instructions which, when executed on a computer, cause the computer to perform the method of any one of claims 1-23.