Communication method and device

Abstract

Embodiments of the present application provide a communication method and apparatus for improving the robustness of a communication process and the accuracy of a perception result. The communication method includes: generating a first physical layer protocol data unit (PPDU), the first PPDU including a first field for indicating that the degree of change in a channel state does not exceed a threshold; and sending the first PPDU.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the Intellectual Property Office of the People's Republic of China on April 26, 2021, with application number 202110456293.4 and invention name "A Communication Method and Device", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of wireless communication technology, and in particular to a communication method and device. Background Art

[0004] In the wireless passive sensing process, such as Figure 1a and Figure 1b As shown, a sensing transmitter sends a null data packet announcement (NDPA) and a null data packet (NDP), and one or more sensing receivers measure channel state information (CSI).

[0005] exist Figure 1a In the process, Sensing Transmitter sends a feedback request. If Sensing Receiver 1 measures that the change in CSI meets the threshold, Sensing Receiver 1 sends an ACK message to station (STA) 1. Sensing Transmitter sends a feedback trigger, and Sensing Receiver 1 sends feedback. Figure 1bIn this scenario, Sensing Transmitter sends a Feedback request. If Sensing Receiver 1 detects a change in the CSI that meets the threshold, Sensing Receiver 1 sends Feedback. That is, if the threshold is met, Sensing Receiver 1 considers the CSI change significant and provides an ACK or Feedback. If the threshold is not met, Sensing Receiver 1 considers the CSI change minor and does not provide any feedback. Thus, if Sensing Transmitter receives an ACK or Feedback, it can determine that Sensing Receiver 1 has measured a significant change in the CSI. If it does not receive an ACK or Feedback, it can determine that Sensing Receiver 1 has measured a minor change in the CSI.

[0006] However, due to factors such as poor channel quality or packet loss, the Sensing Receiver may send ACK or Feedback information but not be received by the Sensing Transmitter. Alternatively, the Sensing Receiver may not receive the Feedback request and therefore not send ACK or Feedback information. Therefore, when the Sensing Transmitter does not receive any information, it may mistakenly believe that the CSI change is small, resulting in inaccurate sensing. Summary of the Invention

[0007] The present application provides a communication method and device to improve the accuracy of perception.

[0008] In a first aspect, a communication method is provided. In this method, a first communication device generates a first physical layer protocol data unit (PPDU), wherein the first PPDU includes a first field, the first field being used to indicate that a change in a channel state does not exceed a threshold. The first communication device transmits the first PPDU, and a second communication device receives the first PPDU. The second communication device may determine that the change in the channel state does not exceed the threshold.

[0009] In this communication method, the first communication device is used as the receiver and the second communication device is used as the transmitter. The receiver can be an access point (AP) or a station (STA), and the transmitter can be either an AP or a STA. By setting the first field to indicate that the change in the channel state has not exceeded a threshold, the transmitter can determine that the change in the channel state is small based on the received feedback. This improves the transmitter's accuracy in distinguishing feedback, enhances the robustness of the communication system, and ultimately improves the accuracy of the perception results.

[0010] In one possible design, the first field is also used to indicate that the degree of change in the channel state exceeds a threshold, and the second communication device can also determine that the degree of change in the channel state exceeds the threshold. Here, by setting the first field to indicate that the degree of change in the channel state exceeds the threshold, the sender can determine that the degree of change in the channel state is large based on the received feedback. Moreover, when the sender does not receive any feedback, it can also determine that the sender has not received the feedback information from the receiver. Therefore, the accuracy of the sender's feedback identification and the accuracy of the perception results can be further improved.

[0011] In one possible design, when the first field is used to indicate that the degree of change in the channel state does not exceed a threshold, the first field can be used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not exceed the threshold; or the first field can be used to indicate the length of the first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state does not exceed the threshold; or the first field can be a second long training field, and the information carried on the subcarriers of the second long training field is used to indicate that the degree of change in the channel state does not exceed the threshold; or the first field can be used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state does not exceed the threshold. By setting the first field, it can be implicitly indicated that the degree of change in the channel state does not exceed the threshold, thereby improving the accuracy of the transmitter's identification feedback.

[0012] In one possible design, when the first field is used to indicate that the degree of change in the channel state does not exceed a threshold, the first field may include negative acknowledgement information, where the negative acknowledgement information is used to indicate that the degree of change in the channel state does not exceed the threshold. By setting the first field, it can be explicitly indicated that the degree of change in the channel state does not exceed the threshold, thereby improving the accuracy of feedback identification by the transmitting end.

[0013] For example, the negative information may be non-acknowledgement (NACK) information or not met (Not met) information.

[0014] Optionally, the negative acknowledgement information may be carried in the preamble of the first PPDU, or the negative acknowledgement information may be carried in the MAC frame of the first PPDU.

[0015] In one possible design, if the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state does not exceed a threshold: the number of symbols in the first long training field is less than the number of space-time streams NSTS; the number of symbols in the first long training field is less than the number of spatial streams NSS; the number of symbols in the first long training field belongs to the first set; the number of symbols in the first long training field belongs to the second set, and the NSTS belongs to the third set; the number of symbols in the first long training field belongs to the fourth set, and the NSS belongs to the fifth set.

[0016] Or optionally, when the number of symbols in the first long training field is greater than or equal to NSTS, it can be used to indicate that the degree of change in the channel state does not exceed the threshold, or when the number of symbols in the first long training field is greater than or equal to NSS, it can be used to indicate that the degree of change in the signaling state does not exceed the threshold.

[0017] In one possible design, the first field is also used to indicate when the degree of change in the channel state exceeds a threshold. The first field can be used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state exceeds the threshold; or the first field can be used to indicate the length of the first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state exceeds the threshold; or the first field can be a second long training field, and the information carried on the subcarriers of the second long training field is used to indicate that the degree of change in the channel state exceeds the threshold; or the first field can be used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state exceeds the threshold. By setting the first field, it can be implicitly indicated that the degree of change in the channel state exceeds the threshold, thereby improving the accuracy of the transmitter's identification feedback.

[0018] In one possible design, when the first field is used to indicate that the degree of change in the channel state exceeds a threshold, the first field may include confirmation information, where the confirmation information is used to indicate that the degree of change in the channel state does not exceed the threshold. By setting the first field to explicitly indicate that the degree of change in the channel state does not exceed the threshold, the accuracy of feedback identification by the transmitting end can be improved.

[0019] For example, the confirmation information may be confirmation (ACK) information or meet (Met) information.

[0020] Optionally, the confirmation information may be carried in the preamble of the first PPDU, or the negative confirmation information may be carried in the MAC frame of the first PPDU.

[0021] In one possible design, if the number of symbols in the first long training field meets any of the following conditions, it is used to indicate that the degree of change in the channel state exceeds a threshold: the number of symbols in the first long training field is greater than NSTS; the number of symbols in the first long training field is greater than NSS; the number of symbols in the first long training field belongs to the sixth set; the number of symbols in the first long training field belongs to the seventh set, and the NSTS belongs to the eighth set; the number of symbols in the first long training field belongs to the ninth set, and the NSS belongs to the tenth set.

[0022] Or optionally, when the number of symbols in the first long training field is less than or equal to NSTS, it can be used to indicate that the degree of change in the channel state exceeds a threshold, or when the number of symbols in the first long training field is less than or equal to NSS, it can be used to indicate that the degree of change in the signaling state exceeds a threshold.

[0023] In one possible design, when the first field is used to indicate the number of symbols of the first long training field, the first field may be an NSTS field, and the NSTS field is used to indicate the number of symbols of the first long training field; or the first field may be the number of symbols of the ultra-high throughput long training field, Number of EHT-LTF Symbols field, and the Number of EHT-LTF Symbols field is used to indicate the number of symbols of the first long training field; or the first field may be an NSTS and midamble periodicity field, and the NSTS And Midamble Periodicity field is used to indicate the number of symbols of the first long training field; or the first field may include a modulation and coding strategy MCS field, and the MCS field is used to indicate the number of symbols of the first long training field; or the first field may include an MCS field and a space-time block coding STBC field, and the MCS field and the STBC field are used to indicate the number of symbols of the first long training field; or the first field may include an MCS field, an STBC field, and an extended spatial stream number NESS field, and the MCS field, the STBC field, and the NESS field are used to indicate the number of symbols of the first long training field.

[0024] In one possible design, the first PPDU may be an empty data packet NDP, or the first PPDU may include a media access control MAC frame. The NDP has no data field, which can save feedback overhead and improve feedback efficiency.

[0025] In one possible design, the first PPDU includes a MAC frame, and the MAC frame also includes a degree of change in the channel state, which can further improve the accuracy of perception.

[0026] In one possible design, the second communication device sends a second PPDU, and the first communication device receives the second PPDU. The second PPDU may be used to indicate that feedback is to be provided when the degree of change in the channel state does not exceed a threshold. Based on the indication in the second PPDU, the first communication device may set the first field to indicate that the degree of change in the channel state does not exceed the threshold, thereby improving the accuracy of the transmitting end in identifying feedback.

[0027] In one possible design, the second PPDU may also be used to indicate feedback when the degree of change in the channel state exceeds a threshold. Through the indication of the second PPDU, the first communication device may set the first field to indicate that the degree of change in the channel state exceeds the threshold, thereby improving the accuracy of the transmitting end in identifying feedback.

[0028] In a second aspect, a communication device is provided for implementing the various methods described above. The communication device may be the first communication device described in the first aspect, or a device including the first communication device, or a device included in the first communication device, such as a chip; or the communication device may be the second communication device described in any of the first aspects, or a device including the second communication device, or a device included in the second communication device. The communication device includes modules, units, or means corresponding to the methods described above, which may be implemented by hardware, software, or by hardware executing corresponding software implementations. The hardware or software includes one or more modules or units corresponding to the above functions. For example, it includes a processing module and a transceiver module coupled to each other.

[0029] In a third aspect, a communication device is provided. The communication device may be the first communication device or the second communication device of the first aspect, or a chip configured in the first communication device or the second communication device of the first aspect. The communication device includes a communication interface and a processor, and optionally, a memory. The memory is configured to store computer programs, instructions, or data. The processor is coupled to the memory and the communication interface. When the processor reads the computer program, instructions, or data, the communication device executes the method performed by the first communication device or the second communication device of the first aspect.

[0030] It should be understood that the communication interface can be implemented by an antenna, feeder, codec, etc. in the communication device. Alternatively, if the communication device is a chip provided in the first communication device or the second communication device, the communication interface can be an input / output interface of the chip, such as an input / output pin. The communication device may also include a transceiver for communicating with other devices. For example, when the communication device is the first communication device, the other device is the second communication device; or, when the communication device is the second communication device, the other device is the first communication device.

[0031] In a fourth aspect, a chip system is provided. The chip system includes a processor and may also include a memory, configured to implement the method performed by the first communication device or the second communication device in the first aspect. In one possible implementation, the chip system also includes a memory for storing program instructions and / or data. The chip system may be composed of a chip alone or may include a chip and other discrete components.

[0032] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program. When the computer program is run, it implements the method performed by the first communication device in the above-mentioned first aspect; or implements the method performed by the second communication device in the above-mentioned first aspect.

[0033] In a sixth aspect, a computer program product is provided, comprising: a computer program code, which, when run, causes the method performed by the first communication device in the above-mentioned first aspect to be executed, or causes the method performed by the second communication device in the above-mentioned first aspect to be executed.

[0034] In a seventh aspect, a communication system is provided, which includes the first communication device described in the first aspect and the second communication device described in the first aspect.

[0035] Among them, the technical effects brought about by any design method in the second to seventh aspects can refer to the technical effects brought about by the different design methods in the above-mentioned first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1a A schematic diagram of a perceptual process;

[0037] Figure 1b A schematic diagram of a perceptual process;

[0038] Figure 2 A schematic diagram of a perception system provided in an embodiment of the present application;

[0039] Figure 3A schematic diagram of a communication system provided in an embodiment of the present application;

[0040] Figure 4a A schematic diagram of a communication system in a home environment provided by an embodiment of the present application;

[0041] Figure 4b A schematic diagram of a communication system in an office environment provided in an embodiment of the present application;

[0042] Figure 5 A schematic diagram of the functional modules of a master control node and a measurement node provided in an embodiment of the present application;

[0043] Figure 6 A schematic diagram of a communication process provided in an embodiment of the present application;

[0044] Figure 7a A schematic diagram of a PPDU frame structure provided in an embodiment of the present application;

[0045] Figure 7b A schematic diagram of a PPDU frame structure provided in an embodiment of the present application;

[0046] Figure 7c A schematic diagram of a PPDU frame structure provided in an embodiment of the present application;

[0047] Figure 7d A schematic diagram of a PPDU frame structure provided in an embodiment of the present application;

[0048] Figure 7e A schematic diagram of a PPDU frame structure provided in an embodiment of the present application;

[0049] Figure 7f A schematic diagram of a PPDU frame structure provided in an embodiment of the present application;

[0050] Figure 8a A schematic diagram of a perception process provided in an embodiment of the present application;

[0051] Figure 8b A schematic diagram of a perception process provided in an embodiment of the present application;

[0052] Figure 8c A schematic diagram of a perception process provided in an embodiment of the present application;

[0053] Figure 9 A schematic diagram of a frame structure provided in an embodiment of the present application;

[0054] Figure 10a A schematic diagram of a perception process provided in an embodiment of the present application;

[0055] Figure 10bA schematic diagram of a perception process provided in an embodiment of the present application;

[0056] Figure 10c A schematic diagram of a perception process provided in an embodiment of the present application;

[0057] Figure 10d A schematic diagram of a perception process provided in an embodiment of the present application;

[0058] Figure 11 A schematic diagram of the structure of a communication device provided in an embodiment of the present application;

[0059] Figure 12 A schematic structural diagram of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0060] The present application will be described in further detail below with reference to the accompanying drawings.

[0061] This application will present various aspects, embodiments, or features in the context of systems that may include multiple devices, components, modules, etc. It should be understood and appreciated that each system may include additional devices, components, modules, etc., and / or may not include all of the devices, components, modules, etc. discussed in conjunction with the figures. Furthermore, combinations of these aspects may also be used.

[0062] Additionally, in the embodiments of this application, the word "exemplary" is used to indicate an example, illustration, or description. Any embodiment or design described in this application as "exemplary" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of the word "exemplary" is intended to present concepts in a concrete manner.

[0063] The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field will know that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0064] The embodiments of the present application can be applied to wireless local area network (WLAN) scenarios and can be applicable to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 system standards, such as 802.11a / b / g, 802.11n, 802.11ac, 802.11ax, or their successors, such as 802.11be or even later generations. Alternatively, they can be applied to 802.11bf. Alternatively, the embodiments of the present application can also be applied to wireless local area network systems such as the Internet of Things (IoT) network or the Vehicle to X (V2X) network. Of course, the embodiments of the present application can also be applied to other possible communication systems, such as long-term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), world-wide interoperability for microwave access (WiMAX) communication system, fifth generation mobile communication technology (5G) communication system and future communication systems.

[0065] The following explains some of the terms used in the embodiments of the present application to facilitate understanding by those skilled in the art.

[0066] 1) Wireless passive sensing, a technology that uses the influence of objects on radio waves to sense the existence, action, and movement of objects.

[0067] With the development of wireless communication technologies such as WLAN, fourth-generation mobile communication technology (4G), and 5G, various wireless communication devices have become widely deployed in people's daily lives. Wireless communication devices can include mobile phones, computers, wireless routers, smart home devices, wireless sensors, and wireless routers. For example, a home environment often contains several, dozens, or even hundreds of wireless communication devices, all of which are in close proximity to the user and objects such as furniture. During wireless communication, these wireless communication devices can sense interference caused by human bodies and objects on the radio waves. This interference can be used to detect human bodies and objects. This is the working principle of wireless passive sensing technology. Simply put, wireless passive sensing technology uses a principle similar to "human radar" to sense surrounding human bodies and objects.

[0068] In a WLAN scenario, the wireless passive sensing technology may be a WLAN sensing technology. The following mainly describes the embodiment of the present application using an example of a WLAN scenario.

[0069] 2) Sensing Transmitter: A device that sends the signal used for sensing measurement during the sensing process. The transmitter can also be called the signal transmitter or the transmitter.

[0070] The sending end may be a wireless access point (AP) or a station (STA).

[0071] 3) Sensing Receiver: The device that receives the signal used for sensing measurement during the sensing process and performs sensing measurement. The receiving end can also be called the signal receiving end or the receiving end.

[0072] The receiving end can be an AP or a STA.

[0073] 4) The STAs referred to in the embodiments of the present application may be various user terminals, user devices, access devices, subscriber stations, subscriber units, mobile stations, user agents, user equipment, or other names with wireless communication capabilities. User terminals may include various handheld devices, vehicle-mounted devices, wearable devices, computing devices, or other processing devices connected to a wireless modem with wireless communication capabilities, as well as various forms of user equipment (UE), mobile stations (MS), terminals, terminal equipment, portable communication devices, handsets, portable computing devices, entertainment devices, gaming devices or systems, global positioning system devices, or any other suitable devices configured to conduct network communications via a wireless medium. For example, a STA may be a communication server, router, switch, or bridge. For the sake of convenience, the above-mentioned devices are collectively referred to as stations or STAs.

[0074] The AP and STA involved in the embodiments of the present application may be APs and STAs applicable to the IEEE 802.11 system standard. An AP is a device deployed in a wireless communication network to provide wireless communication functions for its associated STAs. The AP can be used as the hub of the communication system, and is typically a network-side product that supports the media access control (MAC) and physical layer (PHY) of the 802.11 system standard. For example, it may be a base station, router, gateway, repeater, communication server, switch or bridge and other communication equipment, wherein the base station may include various forms of macro base stations, micro base stations, relay stations, etc. Here, for the sake of convenience of description, the above-mentioned devices are collectively referred to as APs. STAs are typically terminal products that support the MAC and PHY of the 802.11 system standard, such as mobile phones, laptops, etc.

[0075] 5) CSI refers to the channel measurement result obtained by the receiver after measuring the training packets sent by the transmitter, which can be used to reflect the status of the (wireless) channel of the link between the receiver and the transmitter.

[0076] In WLAN protocols, channel state information (CSI) is measured for each orthogonal frequency division multiplexing (OFDM) subcarrier group, obtaining the corresponding CSI matrix. The size of a full-dimensional CSI matrix is ​​the number of transmit antennas multiplied by the number of receive antennas, and each matrix element is a complex number consisting of a real and an imaginary part. When the number of antennas and subcarriers is large, the total amount of uncompressed CSI data is also large.

[0077] When measuring the channel, the transmitting end includes training symbols in the training packet. The receiving end performs channel measurement based on the structure of these training symbols. Optionally, the training packet may not include training symbols.

[0078] In this application, "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0079] The term "plurality" in this application refers to two or more.

[0080] In addition, it should be understood that, in the description of this application, words such as "first" and "second" are only used for the purpose of distinguishing the description, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying order.

[0081] See also Figure 2 , shows an architecture diagram of a perception system applicable to the embodiment of the present application. The perception system includes one or more sending terminals (such as Figure 2 ), and one or more receiving ends (such as Figure 2 The transmitting end and the receiving end may be set in the same physical device or in different physical devices.

[0082] During the sensing process, transmitter 101 transmits a signal, and receiver 102 receives it. The signal received by receiver 102 may include direct signal 104 (a signal not affected by detection target 103) and affected signal 105 (a signal affected by detection target 103). When detection target 103 moves, affected signal 105 changes. The superimposed wireless signal of direct signal 104 and affected signal 105 received by receiver 102 also changes accordingly, allowing receiver 103 to detect a change in the wireless channel.

[0083] The wireless channel is quantified as CSI, which can be used to reflect the status of the wireless channel. Changes in the wireless channel are reflected as changes in the amplitude and phase of the CSI.

[0084] Based on the two CSI measurement results and a threshold condition, the receiving end 102 can determine the extent of the CSI change, that is, the extent of the channel change. For example, if the CSI change meets the threshold condition, the receiving end 102 determines that the CSI change is significant. If the CSI change does not meet the threshold condition, the receiving end 102 determines that the CSI change is minor. If the CSI change is significant, the receiving end 101 can further interact with the receiving end 102 to achieve more accurate perception.

[0085] Compared to wearable devices such as cameras or bracelets, wireless passive sensing requires no additional hardware costs and users do not need to wear devices, making it convenient for monitoring the elderly and children and detecting possible intrusions by thieves. Wireless passive sensing technology has little impact on user privacy and can monitor areas such as bedrooms and bathrooms, providing more comprehensive protection. In addition, wireless passive sensing technology can effectively sense in poor lighting conditions and in the presence of obstructions (such as curtains and wooden furniture), and can also perform multi-room sensing across walls. In addition, wireless passive sensing has very high perception accuracy and can be used for gesture recognition and respiratory sleep monitoring.

[0086] like Figure 3 The communication system includes one or more master nodes, such as Figure 3 The communication system also includes one or more measurement nodes, such as Figure 3 The measurement nodes 202, 203, and 204 are shown in FIG. The link sent by the measurement nodes and received by the master node is called uplink 210. The link sent by the master node and received by the measurement node is called downlink 211. Master node 201 interacts with other master nodes 205 via control link 212. Control link 212 can be connected via wired Ethernet or wireless network and is used to coordinate detection between different master nodes.

[0087] The master control node can be a network element that supports WiFi or other wireless network protocols. For example, the master control node can be deployed in a WLAN access point or smart home control center. The measurement node can be a mobile device such as a mobile phone, or a device with integrated WLAN functionality, such as a printer, smart printer, or smart light. The master control node and measurement nodes can interact using a wireless network protocol (such as WiFi). The master control node can send downlink measurement packets to the measurement node and coordinate the measurement node to perform CSI measurements, thereby obtaining the presence and movement of surrounding people / objects through CSI.

[0088] The transmitting end in the sensing process can be a master control node or a measurement node, and the receiving end can be a master control node or a measurement node. Alternatively, the master control node can be the transmitting end or the receiving end in the sensing process, and the measurement node can be the transmitting end or the receiving end in the sensing process. Of course, it is possible that the master control node can be neither the transmitting end nor the receiving end, and can control multiple measurement nodes to act as transmitting ends and receiving ends, respectively, which is not limited in the embodiments of the present application.

[0089] Figure 3 The communication system shown can be applied to home scenarios and office scenarios.

[0090] Family scenes can be Figure 4a As shown, Figure 4a In the home environment shown in FIG, a master control node 301 and multiple measurement nodes, such as measurement nodes 302, 303, 304, 305, 306, 307, and 308, are deployed. Master control node 301 can interact with multiple measurement nodes to monitor the entire home environment. For example, the link between master control node 301 and measurement node 305 can be used to measure bathroom activity. If a slip is detected, master control node 301 can promptly issue an alarm to notify a guardian or medical staff. Another example is that the links between master control node 301 and measurement nodes 302, 303, and 306 can be used to measure bedroom activity and monitor a user's sleep.

[0091] Office scenes can be applied in industrial and commercial environments. Figure 4b As shown, the area to be monitored in an office scenario is typically large, and multiple master control nodes can be used, such as master control node 401, master control node 402, and master control node 403. The master control nodes interact with different measurement nodes to complete measurements of a specific area. For example, the link between master control node 401 and measurement node 410 can be used to monitor entrances and exits. Another example is the link between master control node 403 and measurement node 413, which can be used to count conference room occupancy and attendance.

[0092] The communication system provided above is only an example. It can be understood that the communication system using the solution of the present application is not limited to this. It is described here uniformly and will not be repeated below.

[0093] Optionally, the master node and the measurement node can Figure 5 The functional modules in are implemented. Figure 5 This is a structural diagram of the master control node functional module and a structural diagram of the measurement node functional module provided in an embodiment of the present application.

[0094] The master control node functional module includes a master control node selection module 501, a measurement node status recording module 502, a measurement process interaction module 503, a CSI information processing module 504, and a CSI measurement module 505. The master control node selection module 501 can be responsible for selecting a master control node from multiple nodes that can assume the master control node role, and can also be responsible for interaction between master control nodes. The measurement node status recording module 502 can be responsible for storing information about all measurement nodes under the master control node. The measurement node information includes, but is not limited to, at least one of the following: a measurement node identifier (such as the measurement node's MAC address, the measurement node's association identifier (AID), a sensing identifier (SID) assigned to unassociated measurement nodes), the measurement node's sensing capabilities, the measurement node's location, the measurement node's CSI measurement history information, and the threshold conditions for triggering measurement node sensing. The measurement process interaction module 503 can be responsible for protocol processing for interaction between the master control node and the measurement node. The CSI information processing module 504 can be responsible for processing the collected CSI information. The CSI measurement module 505 may be responsible for measuring the training symbols in the measurement group sent by the measurement node. After receiving the measurement group, it may output the uplink CSI measurement matrix for each subcarrier or subcarrier group. It may also be responsible for handing the uplink CSI measurement matrix to the CSI information processing module 504 for subsequent processing.

[0095] The measurement node functional module includes a measurement process interaction module 510, a CSI measurement module 511, and a measurement node local information module 512. The measurement process interaction module 510 is responsible for responding to measurement interaction information from the master control node. The CSI measurement module 511 is responsible for measuring the measurement packets sent by the master control node and obtaining the downlink CSI measurement matrix. The measurement node local information module 512 is responsible for storing measurement-related information. This measurement-related information includes, but is not limited to, at least one of the following: a measurement session identifier, the measurement node's last CSI measurement history, and the timestamp of the measurement node's last feedback.

[0096] Figure 5 Each functional module in the master control node and the measurement node can be implemented by a hardware chip or by firmware refresh, or some functional modules (such as the master control node selection module 501 or the CSI information processing module 504, etc.) can be implemented by an operating system or driver software.

[0097] It is understandable that Figure 5The structure shown does not constitute a specific limitation on the master control node and the measurement node. For example, in other embodiments of the present application, the master control node and the measurement node may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure can be implemented in hardware, software, or a combination of software and hardware. For example, the master control node includes a transceiver, a memory, and a processor. The transceiver can implement the function of the measurement process interaction module 503, the memory can implement the function of the measurement node status recording module 502, and the processor can implement the function of the master control node selection module 501, the CSI information processing module 504, and the CSI measurement module 505. For another example, the master control node includes a transceiver, a memory, and a processor. The transceiver can implement the function of the measurement process interaction module 510, the memory can implement the function of the measurement node local information module 512, and the processor can implement the function of the CSI measurement module 511.

[0098] The following will be combined Figures 2 to 5 The communication method provided in the embodiments of the present application is described in detail using the interaction between a first communication device and a second communication device as an example. The first communication device may be a receiving end, and the second communication device may be a transmitting end. The transmitting end may be an AP or a STA, and the receiving end may be an AP or a STA.

[0099] It is understood that in the embodiments of the present application, the first communication device and / or the second communication device may perform some or all of the steps in the embodiments of the present application. These steps or operations are merely examples, and the embodiments of the present application may also perform other operations or variations of various operations. In addition, the various steps may be performed in a different order than those presented in the embodiments of the present application, and it is possible that not all of the operations in the embodiments of the present application need to be performed.

[0100] It should be noted that the message names between the devices or the names of the parameters in the messages in the following embodiments of the present application are only examples. Other names may be used in specific implementations, and the embodiments of the present application do not specifically limit this.

[0101] In the communication method provided in the embodiment of the present application, the first communication device can provide feedback when it determines that the degree of change in the channel state does not meet the threshold condition, and the second communication device can determine that the degree of change in the channel state does not meet the threshold condition. The first communication device can also provide feedback when the degree of change in the channel state meets the threshold condition, and the second communication device can determine that the degree of change in the channel state meets the threshold condition. And when the second communication device does not receive any feedback, it can also determine that the second communication device has not received the information fed back by the first communication device. Therefore, the accuracy of the second communication device in distinguishing feedback can be improved, the robustness of the communication system can be improved, and the accuracy of the perception results can be improved.

[0102] like Figure 6 FIG. 1 shows a possible communication process provided by an embodiment of the present application. The communication process includes the following steps:

[0103] Optional S601: The second communication device sends a second physical layer protocol data unit (PPDU), and the first communication device receives the second PPDU.

[0104] The second PPDU is used to trigger the first communication device to provide feedback. The second PPDU may be similar to a Feedback request frame, a Feedback Trigger frame, or a Poll frame.

[0105] Optionally, the second PPDU may be used to indicate that feedback is provided when the degree of change in the channel state does not meet a threshold condition. When the degree of change in the channel state does not meet the threshold condition, the degree of change in the channel state may be considered to be small. The degree of change in the channel state not meeting the threshold condition may also be expressed in other ways, such as, for example, the degree of change in the channel state does not exceed a threshold, or the degree of similarity in the channel state is greater than a threshold, etc., without limitation herein.

[0106] For example, the second PPDU is used to indicate that negative feedback information is fed back when the degree of change in the channel state does not meet a threshold condition. Optionally, the negative feedback information can be non-acknowledgement (NACK) information, or the negative feedback information can be NotMeet information. For another example, the second PPDU is used to indicate that a PPDU is fed back when the degree of change in the channel state does not meet a threshold condition. The fed back PPDU includes first information and second information. The first information is used to indicate that the degree of change in the channel state does not meet the threshold condition, and the second information is information related to the channel state.

[0107] The information related to the channel state may include one or more of the following information: channel measurement results, complete CSI information, compressed CSI information or NDP, etc.

[0108] Alternatively, the second PPDU may also be used to indicate that feedback is to be provided when the degree of change in the channel state meets a threshold condition. When the degree of change in the channel state meets the threshold condition, it can be considered that the degree of change in the channel state is significant. The degree of change in the channel state meeting the threshold condition may also be expressed in other ways, such as when the degree of change in the channel state exceeds a threshold, or when the degree of similarity in the channel state exceeds a threshold, etc., without limitation herein.

[0109] For example, the second PPDU is used to indicate that confirmation information is fed back when the degree of change in the channel state meets a threshold condition. Optionally, the confirmation information can be confirmation (NACK) information, or the confirmation information can be met (Met) information. In another example, the second PPDU is used to indicate that a PPDU is fed back when the degree of change in the channel state meets a threshold condition. The fed-back PPDU includes first information and second information. The first information indicates that the degree of change in the channel state meets the threshold condition, and the second information is information related to the channel state.

[0110] S602: The first communication device generates a first physical layer protocol data unit (PPDU).

[0111] The first communication device may send a feedback response based on a determination result of whether the degree of change in the channel device satisfies a threshold condition. The feedback response may be in the form of a PPDU (e.g., a first PPDU), or may be included in a PPDU (e.g., a MAC frame in the first PPDU, or information included in the MAC frame in the first PPDU).

[0112] The first PPDU includes a first field. The first field may be used to indicate that the degree of change in the channel state does not meet a threshold condition. The first field may also be used to indicate that the degree of change in the channel state meets a threshold condition.

[0113] The first field may be equivalent to information indicated by n bits (bits), where n is a positive integer, n=1, 2, 3, .... Here, the first field is equivalent to information indicated by 1 bit as an example. For example, when the value of the 1 bit is 1, it may indicate that the degree of change in the channel state meets the threshold condition, and when the value of the 1 bit is 0, it may indicate that the degree of change in the channel state does not meet the threshold condition. Or conversely, when the value of the 1 bit is 1, it may indicate that the degree of change in the channel state does not meet the threshold condition, and when the value of the 1 bit is 0, it may indicate that the degree of change in the channel state does not meet the threshold condition.

[0114] Optionally, the first field may implicitly indicate whether the degree of change in the channel state satisfies a threshold condition.

[0115] One possible approach is to set a different number of symbols in the first long training field to indicate whether the degree of change in the channel state meets a threshold condition. For example, the first field is used to indicate the number of symbols in the first long training field. The number of symbols in the first long training field can be used to indicate that the degree of change in the channel state does not meet the threshold condition. The number of symbols in the first long training field can also be used to indicate that the degree of change in the channel state meets the threshold condition. For example, when the degree of change in the channel state is small, the first communications device may carry the number of symbols in the first long training field in the first PPDU to indicate that the degree of change in the channel state does not meet the threshold condition. The second communications device may determine that the degree of change in the channel state is small based on the received feedback. For another example, when the degree of change in the channel state is large, the first communications device may carry the number of symbols in the first long training field in the first PPDU to indicate that the degree of change in the channel state meets the threshold condition. The second communications device may determine that the degree of change in the channel state is large based on the received feedback.

[0116] The number of symbols in the first long training field is variable, that is, the number of symbols in the first long training field can be changed, that is, the number of symbols in the first long training field is not fixed. For example, the first long training symbol can be represented as xx-long training field (LTF), and xx-LTF can be a name in various generations of WLAN standards, such as high throughput (HT)-LTF, very high throughput (VHT)-LTF, high efficiency (HE)-LTF, and extremely high throughput (EHT)-LTF. Optionally, for example, in the 802.11be standard, the first long training field can be EHT-LTF, in the 802.11ax standard, the first long training field can be HE-LTF, in the 802.11n standard, the first long training field can be HT-LTF, and in the 802.11ac standard, the first long training field can be VHT-LTF. It should be noted that the number of symbols in the legacy-long training field (L-LTF) is fixed and cannot be changed. Therefore, the first long training field involved in the embodiment of the present application is not L-LTF.

[0117] The first field may include, but is not limited to, the following fields: the number of space-time streams (NSTS) field, or the number of EHT-LTF symbols (Number of EHT-LTF Symbols) field, or the modulation and coding scheme (MCS), or the NSTS and midamble periodicity (NSTS And Midamble Periodicity) field, etc., without limitation herein. Optionally, for example, in the 802.11be standard, the first field may be the Number of EHT-LTF Symbols field. In the 802.11ax standard, the first field may be the NSTS And Midamble Periodicity field. In the 802.11ac standard, the first field may be the NSTS field. In the 802.11n standard, the first field may include the MCS field, or the first field may include the MCS field and the space-time block code (STBC) field, or the first field may include the MCS field, the STBC field, and the number of extension spatial streams (NESS) field. That is, the number of symbols in the first long training field may be determined by the value of the MCS field, or by the value of the MCS field and the STBC field, or by the value of the MCS field, the STBC field and the NESS field.

[0118] As explained below, the number of symbols in the first long training field is determined by the values ​​of the MCS field, the STBC field, and the NESS field. The values ​​of the MCS field and the STBC field correspond to the value of NSTS, the value of the NESS field corresponds to the value of the number of high-throughput extended long training fields (Number of HT-Extension Long Training field, NHT-ELTF) field, and the value of NSTS corresponds to the number of high-throughput data long training fields (Number of HT-Data Long Training field, NHT-DLTF). The number of symbols in the first long training field can be determined by summing the values ​​of the NHT-ELTF field and the NHT-DLTF field.

[0119] The first PPDU may also include one or more first long training fields. Optionally, the format of the first PPDU complies with the WLAN standard. The format of the PPDU may be different in different generations of WLAN standards. For example, in the 802.11be standard, a possible PPDU format is as follows: Figure 7a As shown, the PPDU includes a legacy-short training field (L-STF), L-LTF, a legacy signaling field (L-SIG), a repeated legacy signaling field (RL-SIG), a universal signaling field (U-SIG), an EHT-SIG, an EHT-STF, an EHT-LTFs and a packet extension (PE) field. The EHT-SIG includes a Number of EHT-LTF Symbols field, which includes the number of symbols in the first long training field. For example, in the 802.11ax standard, a possible PPDU format is as follows: Figure 7b As shown, the PPDU contains L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, HE-STF, HE-LTF and PE. HE-SIG-A contains the NSTS And Midamble Periodicity field, which contains the number of symbols of the first long training field. For example, in the 802.11n standard, a possible PPDU format is as follows Figure 7c As shown, the PPDU contains HT-greenfield (GT)-STF, HT-LTF1, HT-SIG and HT-LTF2. Among them, the HT-SIG contains the MCS field, and the MCS field contains the number of symbols of the first long training field. In the 802.11n standard, another possible PPDU format is as follows Figure 7d As shown, PPDU contains L-STF, L-LTF, L-SIG, HT-SIG, HT-STF and HT-LTF. For example, in the 802.11ac standard, a possible PPDU format is as follows Figure 7e As shown, the PPDU contains L-STF, L-LTF, L-SIG, VHT-SIG-A, VHT-STF, VHT-LTF and VHT-SIG-B. Among them, VHT-SIG-A contains the NSTS field, and the NSTS field contains the number of symbols of the first long training field. It should be noted that Figure 7a , Figure 7b , Figure 7c , Figure 7e and Figure 7d The length of each field in is only an example and does not limit the number of symbols or bits occupied by each field.

[0120] For example, whether the degree of change in the channel state meets the threshold condition may be determined by the number of symbols in the first long training field and the size of the NSTS or the number of spatial streams (NSS).

[0121] For example, the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not meet the threshold condition, including one of the following: the number of symbols in the first long training field is greater than or equal to NSTS, the number of symbols in the first long training field is less than or equal to NSTS, the number of symbols in the first long training field is greater than or equal to NSS, or the number of symbols in the first long training field is less than or equal to NSS.

[0122] The number of symbols in the first long training field is used to indicate that the degree of change in the channel state meets the threshold condition, including one of the following: the number of symbols in the first long training field is less than or equal to NSTS, the number of symbols in the first long training field is greater than or equal to NSTS, the number of symbols in the first long training field is less than or equal to NSS, or the number of symbols in the first long training field is greater than or equal to NSS.

[0123] For another example, whether the degree of change in the channel state meets a threshold condition may be determined by the range of the number of symbols in the first long training field.

[0124] For example, the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not meet a threshold condition, including that the number of symbols in the first long training field belongs to the first set.

[0125] The number of symbols in the first long training field is used to indicate that the degree of change in the channel state meets a threshold condition, including that the number of symbols in the first long training field belongs to a sixth set.

[0126] The first set and the sixth set are different. Optionally, the first set may be related to NSTS or NSS. For example, the first set is a set greater than (or equal to) NSTS, or the first set is a set less than (or equal to) NSTS. For another example, the first set is a set greater than (or equal to) NSS, or the first set is a set less than (or equal to) NSS. Optionally, the sixth set may be related to NSTS or NSS. For example, the sixth set is a set less than (or equal to) NSTS, or the sixth set is a set greater than (or equal to) NSTS. For another example, the sixth set is a set less than (or equal to) NSS, or the sixth set is a set greater than (or equal to) NSS. For example, the first set includes 1, and the sixth set is a set of integers greater than 1. When the number of symbols in the first long training field is 1, it indicates that the degree of change in the channel state does not meet the threshold condition. When the number of symbols in the first long training field is not 1 (for example, 2), it indicates that the degree of change in the channel state meets the threshold condition.

[0127] For another example, whether the degree of change in the channel state meets the threshold condition may be determined by the range of the number of symbols in the first long training field and the range of NSTS or NSS.

[0128] For example, the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not meet the threshold condition, including one of the following: the number of symbols in the first long training field belongs to the second set, and NSTS belongs to the third set; or the number of symbols in the first long training field belongs to the fourth set, and NSS belongs to the fifth set.

[0129] The number of symbols in the first long training field is used to indicate that the degree of change in the channel state meets the threshold condition, including one of the following: the number of symbols in the first long training field belongs to the seventh set, and NSTS belongs to the eighth set; or the number of symbols in the first long training field belongs to the ninth set, and NSS belongs to the tenth set.

[0130] The second set and the third set may be completely identical, partially identical, or completely different. The fourth set and the fifth set may be completely identical, partially identical, or completely different. The seventh set and the eighth set may be completely identical, partially identical, or completely different. The ninth set and the tenth set may be completely identical, partially identical, or completely different.

[0131] It can be understood that the number of symbols in the first long training field used to indicate that the degree of change in the channel state meets the threshold condition is different from the number of symbols in the first long training field used to indicate that the degree of change in the channel state does not meet the threshold condition, and they respectively meet the above-mentioned respective conditions.

[0132] Another possible approach is to set the length of the first padding field to indicate whether the degree of change in the channel state meets the threshold condition. For example, the first field is used to indicate the length of the first padding field. The length of the first padding field can be used to indicate that the degree of change in the channel state does not meet the threshold condition. The length of the first padding field can also be used to indicate that the degree of change in the channel state meets the threshold condition.

[0133] The length of the first padding field is variable, that is, the length of the first padding field is not fixed.

[0134] For example, the length of the first padding field is used to indicate that the degree of change in the channel state does not meet the threshold condition, including one of the following: the length of the first padding field is greater than or equal to the first length, or the length of the first padding field is less than or equal to the first length. The first length is related to the time length or the number of symbols. There is no restriction on the time length and the number of symbols. For example, the time length representing the first length can be 4 microseconds (μs).

[0135] The length of the first filling field is used to indicate that the degree of change in the channel state meets the threshold condition, including one of the following: the length of the first filling field is less than or equal to the first length, or the length of the first filling field is greater than or equal to the first length.

[0136] It can be understood that the length of the first filling field used to indicate that the degree of change in the channel state meets the threshold condition is different from the length of the first filling field used to indicate that the degree of change in the channel state does not meet the threshold condition, and they respectively meet the above-mentioned respective conditions.

[0137] The first PPDU may also include a first padding field. Optionally, the first PPDU includes a SIG field, which includes the first padding field. Alternatively, the first PPDU includes a PE field, which includes the first padding field. Alternatively, the first PPDU includes a MAC frame, which includes the first padding field.

[0138] Optionally, if the length of the first padding field indicates whether the degree of change in the channel state meets the threshold condition, the first PPDU can be Figure 7a , Figure 7b , Figure 7c , Figure 7d or Figure 7e The PPDU format shown, or the first PPDU can be Figure 7f The PPDU format shown is Figure 7f The PPDU format shown is a Non-HT PPDU. The length of the L-LTF carried in the Non-HT PPDU is fixed.

[0139] In another possible approach, information carried on subcarriers of the second long training field is set to indicate whether the degree of change in the channel state meets a threshold condition. The first field may be the second long training field. The information carried on subcarriers of the second long training field may be used to indicate that the degree of change in the channel state does not meet the threshold condition. The information carried on subcarriers of the second long training field may also be used to indicate that the degree of change in the channel state meets the threshold condition.

[0140] Optionally, the second PPDU in S601 is a trigger frame similar to an NDP feedback report poll (NFRP). That is, the second communication device can trigger the first communication device to provide feedback using a trigger frame similar to an NFRP. The first communication device can carry information on the subcarrier allocated to the first communication device to indicate whether the degree of change in the channel state meets the threshold condition.

[0141] For example, the NFRP trigger frame may be as shown in Table 1. When the value of a field in the NFRP trigger frame is 0, it indicates a resource request, that is, inquiring whether the first communication device has resources (or data, or information) to report. When the value of this field in the NFRP trigger frame is non-zero (for example, 1), it indicates whether the degree of change in the trigger feedback channel status meets the threshold condition.

[0142] Table 1

[0143] Value Description 0 Resource request 1-15 Reserved

[0144] Optionally, if the information carried on the subcarrier of the second long training field indicates whether the degree of change in the channel state meets the threshold condition, the first PPDU can be Figure 7a , Figure 7b , Figure 7c , Figure 7d or Figure 7e The PPDU format shown, or the first PPDU can be Figure 7f The PPDU format is shown.

[0145] Another possible approach is to indicate whether the degree of change in the channel state meets a threshold condition by setting the size (SIZE) of the third long training field. The first field can be used to indicate the SIZE of the third long training field. The SIZE of the third long training field can be the number of subcarriers in the third long training field. The SIZE of the third long training field can have formats such as 1x, 2x, and 4x. The SIZE of the third long training field can be used to indicate that the degree of change in the channel state does not meet the threshold condition. The SIZE of the third long training field can also be used to indicate that the degree of change in the channel state meets the threshold condition.

[0146] For example, the SIZE of the third longest training field is used to indicate that the degree of change in the channel state does not meet the threshold condition, including one of the following: the SIZE of the third longest training field is in 1x format, the SIZE of the third longest training field is in 2x format, or the SIZE of the third longest training field is in 4x format.

[0147] The SIZE of the third longest training field is used to indicate that the degree of change in the channel state meets the threshold condition, including one of the following: the SIZE of the third longest training field is in 1x format, the SIZE of the third longest training field is in 2x format, or the SIZE of the third longest training field is in 4x format.

[0148] It can be understood that the SIZE of the third longest training field used to indicate that the degree of change in the channel state meets the threshold condition is different from the SIZE of the third longest training field used to indicate that the degree of change in the channel state does not meet the threshold condition, and they respectively meet the above respective conditions.

[0149] Optionally, if the SIZE of the third long training field indicates whether the degree of change in the channel state meets the threshold condition, the first PPDU can be Figure 7a , Figure 7b , Figure 7c , Figure 7d or Figure 7e The PPDU format shown, or the first PPDU can be Figure 7f The PPDU format is shown.

[0150] During the sensing process, it is possible to implicitly indicate whether the change in the channel state meets the threshold condition.

[0151] like Figure 8aAs shown, a possible perception process provided by an embodiment of the present application. In the measurement phase, Sensing Transmitter sends NDPA and NDP to instruct one or more Sensing Receivers to perform CSI measurement. In the reporting phase, Sensing Transmitter sends Feedback request, Sensing Receiver1 sends PPDU, PPDU carries Configuration (Configuration) 1, and Configuration1 is used to indicate that the degree of change in the channel state meets the threshold condition, and Sensing Receiver2 sends PPDU, PPDU carries Configuration2, and Configuration2 is used to indicate that the degree of change in the channel state does not meet the threshold condition. Configuration1 and Configuration2 can be the above-mentioned implicit indication methods. Sensing Transmitter sends Feedback Trigger to Sensing Receiver1, and Sensing Receiver1 sends Feedback. The Feedback includes information related to the channel state, such as channel measurement results, complete CSI information, compressed CSI information or NDP, etc.

[0152] In some scenarios, when the degree of change in the channel state is indicated by setting the information carried on the subcarrier of the second longest training field during the perception process to meet the threshold condition, the type of the Feedback request can be NFRP Triggerframe, that is, the Sensing Transmitter can trigger one or more SensingReceivers to send an NDP feedback report response (NDP feedback report response) through the NFRP trigger frame. The Sensing Receiver receives the NFRP trigger frame to determine that it is scheduled, and then carries information on the corresponding subcarrier of the second longest training field in the NDP feedback report response. The first PPDU can be an NDP feedback report response. This can achieve more efficient feedback and save overhead.

[0153] Figure 8bAnother possible perception process provided by an embodiment of the present application. In the measurement phase, Sensing Transmitter sends NDPA and NDP to instruct one or more Sensing Receivers to perform CSI measurement. In the reporting phase, Sensing Transmitter sends Feedback request, Sensing Receiver1 sends Feedback, and the Feedback carries Configuration1, which is used to indicate that the degree of change in the channel state meets the threshold condition, and Sensing Receiver2 sends Feedback, which carries Configuration2, which is used to indicate that the degree of change in the channel state does not meet the threshold condition.

[0154] above Figure 8a and Figure 8b The figure shows the situation where multiple sensing receivers provide feedback simultaneously. There are many ways to provide feedback simultaneously, such as using spatial streams to differentiate, or using orthogonal frequency division multiple access (OFDMA) to differentiate, etc.

[0155] like Figure 8c As shown, another possible perception process provided by an embodiment of the present application. In this perception process, multiple Sensing Receivers can also poll for feedback. In the reporting phase, Sensing Transmitter sends a Feedbackrequest. Then Sensing Transmitter sends a Feedback Trigger to Sensing Receiver1, and Sensing Receiver1 sends Feedback. The Feedback carries Configuration1, and Configuration1 is used to indicate that the degree of change in the channel state meets the threshold condition. Sensing Transmitter sends a Feedback Trigger to Sensing Receiver2, and Sensing Receiver2 sends Feedback. The Feedback carries Configuration2, and Configuration2 is used to indicate that the degree of change in the channel state does not meet the threshold condition. It can be seen that for polling feedback, Sensing Transmitter sends Feedback Trigger to Sensing Receiver to trigger feedback in turn.

[0156] Optionally, the first field may explicitly indicate whether the degree of change in the channel state satisfies a threshold condition.

[0157] The first PPDU may include negative acknowledgement information, where the negative acknowledgement information is used to indicate that the degree of change in the channel state does not meet a threshold condition. Optionally, the negative acknowledgement information may be NACK information, or the negative acknowledgement information may be Not met information.

[0158] The first PPDU may also include confirmation information, where the confirmation information is used to indicate that the degree of change in the channel state meets a threshold condition. Optionally, the confirmation information may be ACK information, or the confirmation information may be Met information.

[0159] Optionally, the first PPDU includes a MAC frame, where the MAC frame is used to indicate that the degree of change in the channel state does not meet a threshold condition, or that the degree of change in the channel state meets a threshold condition. Optionally, the MAC frame may also include, but is not limited to, at least one of the following information: received signal strength, signal-to-noise ratio, or degree of change in the channel state.

[0160] The specific form of the first PPDU may include various types. For example, a new aggregation control subfield (A-Control subfield) may be defined to carry information on whether the degree of change in the channel state meets the threshold condition. For example, a command and status (CAS) control subfield or a new controlID may be used to indicate whether the degree of change in the channel state meets the threshold condition. Possible data fields in the PPDU format include: Figure 9 As shown, it includes Frame Control, Duration, Address 1, Address 2, Address 3, Sequence Control, Address 4, High-Efficiency Control (HT Control), Frame Body, and Frame Check Sequence (FCS). The HT Control subfield defines a new A-Control subfield, which includes the Control List subfield and the Padding subfield. The Control List subfield includes subfields such as the Control ID and Control Information.

[0161] Optionally, if the degree of change in the channel state satisfies the threshold condition in an explicit manner, the first PPDU may be Figure 7a , Figure 7b , Figure 7c , Figure 7d or Figure 7e The PPDU format shown, or the first PPDU can be Figure 7f The PPDU format is shown.

[0162] During the sensing process, it is possible to explicitly indicate whether the change in the channel state meets the threshold condition.

[0163] like Figure 10a As shown, a possible perception process provided by an embodiment of the present application. In the measurement phase, Sensing Transmitter sends NDPA and NDP to instruct one or more Sensing Receivers to perform CSI measurement. In the reporting phase, Sensing Transmitter sends Feedback request, Sensing Receiver1 sends Met information to indicate that the degree of change in the channel state meets the threshold condition, and Sensing Receiver2 sends Not Met information to indicate that the degree of change in the channel state does not meet the threshold condition. Sensing Transmitter sends Feedback Trigger to SensingReceiver1, and Sensing Receiver1 sends Feedback, which includes information related to the channel state.

[0164] Figure 10b Another possible perception process provided by an embodiment of the present application. In the measurement phase, Sensing Transmitter sends NDPA and NDP to instruct one or more Sensing Receivers to perform CSI measurement. In the reporting phase, Sensing Transmitter sends Feedback request, Sensing Receiver1 sends Feedback, which is used to indicate that the degree of change in the channel state meets the threshold condition, and Sensing Receiver2 sends Feedback Not Met, which is used to indicate that the degree of change in the channel state does not meet the threshold condition.

[0165] above Figure 10a and Figure 10bThe figure shows the situation where multiple sensing receivers provide feedback simultaneously. There are many ways to provide feedback simultaneously, such as using spatial streams to differentiate, or using OFDMA to differentiate.

[0166] like Figure 10c As shown, another possible perception process provided by an embodiment of the present application. In this perception process, multiple Sensing Receivers can also poll for feedback. In the reporting phase, the Sensing Transmitter sends a Feedbackrequest. Then the Sensing Transmitter sends a Feedback Trigger to the Sensing Receiver1, and the Sensing Receiver1 sends a Feedback, which is used to indicate that the degree of change in the channel state meets the threshold condition. The Sensing Transmitter sends a Feedback Trigger to the Sensing Receiver2, and the Sensing Receiver2 sends a Feedback Not Met, which is used to indicate that the degree of change in the channel state does not meet the threshold condition.

[0167] When the Sensing Receiver feeds back whether the degree of change in the channel state meets the threshold condition, it can also feed back more information at the same time, such as at least one of the received signal strength, signal-to-noise ratio, or degree of change in the channel state. Figure 10d As shown, based on 10a, the Met message sent by Sensing Receiver 1 carries more information, and the Not Met message sent by Sensing Receiver 2 carries more information.

[0168] S603: The first communication device sends a first PPDU, and the second communication device receives the first PPDU.

[0169] When the first communication device sends the first PPDU feedback, it may provide feedback simultaneously with other communication devices (ie, other receiving ends), or it may provide feedback in a polling manner.

[0170] S604: The second communication device determines whether the degree of change in the channel state meets a threshold condition based on the first PPDU.

[0171] In the embodiments of the present application, by setting an implicit or explicit indication of whether the degree of change in the channel state meets a threshold condition, the second communication device can determine whether the degree of change in the channel state meets or does not meet the threshold condition based on the received feedback. Furthermore, when the second communication device does not receive any feedback, it can also determine that the second communication device has not received any feedback from the first communication device. This can improve the accuracy of the second communication device in identifying feedback, improve the robustness of the communication system, and thereby improve the accuracy of the perception results.

[0172] In the various embodiments of the present application, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0173] It can be understood that in the above embodiments, the methods and / or steps implemented by the first communication device can also be implemented by components (such as chips or circuits) that can be used for the first communication device, and the methods and / or steps implemented by the second communication device can also be implemented by components that can be used for the second communication device.

[0174] In the embodiments provided above, the methods provided in the embodiments of the present application are described from the perspective of the interaction between the first communication device and the second communication device. In order to implement the various functions of the methods provided in the embodiments of the present application, the first communication device and the second communication device may include hardware structures and / or software modules, and implement the above functions in the form of hardware structures, software modules, or hardware structures plus software modules. Whether one of the above functions is executed in the form of hardware structures, software modules, or hardware structures plus software modules depends on the specific application and design constraints of the technical solution.

[0175] The following describes the communication device used to implement the above method in the embodiment of the present application with reference to the accompanying drawings. Therefore, the above contents can be used in subsequent embodiments, and repeated contents will not be repeated.

[0176] Figure 11A possible form of expression of a communication device provided in an embodiment of the present application, the communication device 1000 can be used to implement the functions or steps implemented by the first communication device or the second communication device in the above-mentioned method embodiment. The communication device may include a processing module 1101 and a transceiver module 1102. Optionally, it may also include a storage unit, which can be used to store instructions (codes or programs) and / or data. The processing module 1101 and the transceiver module 1102 can be coupled to the storage unit. For example, the processing unit 1101 can read the instructions (codes or programs) and / or data in the storage unit to implement the corresponding method. The above-mentioned units can be set independently or partially or fully integrated.

[0177] In some possible implementations, the communication device 1100 can implement the behaviors and functions of the first communication device in the above method embodiment. For example, the communication device 1101 can be an AP, or a component (such as a chip or circuit) used in an AP. The transceiver module 1102 can be used to perform Figure 6 In the embodiment shown, all receiving or sending operations are performed by the first communication device. Figure 6 S601 and S603 in the embodiment shown, and / or other processes for supporting the technology described herein; wherein the processing module 1101 is used to perform the following steps: Figure 6 In the embodiment shown, all operations except the sending and receiving operations performed by the first communication device, such as Figure 6 S602 in the illustrated embodiment, and / or other processes for supporting the techniques described herein.

[0178] For example, the processing unit 1001 is configured to generate a first PPDU, the first PPDU including a first field, the first field being used to indicate that the degree of change in the channel state does not exceed a threshold, or being used to indicate that the degree of change in the channel state exceeds a threshold; the transceiver unit 1102 is configured to send the first PPDU. Alternatively, the transceiver unit 1102 is configured to receive a second PPDU, the second PPDU being used to indicate that feedback is to be provided when the degree of change in the channel state does not exceed a threshold, or being used to indicate that feedback is to be provided when the degree of change in the channel state exceeds a threshold.

[0179] In some possible implementations, the communication device 1100 can implement the behaviors and functions of the second communication device in the above method embodiment. For example, the communication device 1101 can be an AP, or a component (such as a chip or circuit) used in an AP. The transceiver module 1102 can be used to perform Figure 6 In the embodiment shown, all receiving or sending operations are performed by the second communication device. Figure 6S601 and S603 in the embodiment shown, and / or other processes for supporting the technology described herein; wherein the processing module 1101 is used to perform the following steps: Figure 6 In the embodiment shown, all operations except the sending and receiving operations performed by the second communication device, such as Figure 6 S604 in the illustrated embodiment, and / or other processes for supporting the techniques described herein.

[0180] For example, the transceiver unit 1102 is configured to receive a first PPDU; the processing unit 1101 is configured to determine whether the degree of change in the channel state does not exceed a threshold, or to determine whether the degree of change in the channel state exceeds a threshold. Alternatively, the processing unit 1101 is configured to generate a second PPDU, the second PPDU being configured to indicate that feedback is to be provided when the degree of change in the channel state does not exceed a threshold, or to indicate that feedback is to be provided when the degree of change in the channel state exceeds a threshold; and the transceiver unit 1102 is configured to send the second PPDU.

[0181] In a possible implementation of the communication device 1100, the first field is used to indicate that the degree of change in the channel state does not exceed a threshold, including: the first field is used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not exceed a threshold; or the first field is used to indicate the length of the first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state does not exceed a threshold; or the first field is a second long training field, and the information carried on the subcarriers of the second long training field is used to indicate that the degree of change in the channel state does not exceed a threshold; or the first field is used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state does not exceed a threshold.

[0182] In a possible implementation of the communication device 1100, the first field is used to indicate that the degree of change in the channel state does not exceed a threshold, including: the first field includes denial information, and the denial information is used to indicate that the degree of change in the channel state does not exceed a threshold.

[0183] In a possible implementation of the communication device 1100, if the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state does not exceed the threshold: the number of symbols in the first long training field is less than the number of space-time streams NSTS; the number of symbols in the first long training field is less than the number of spatial streams NSS; the number of symbols in the first long training field belongs to the first set; the number of symbols in the first long training field belongs to the second set, and the NSTS belongs to the third set; the number of symbols in the first long training field belongs to the fourth set, and the NSS belongs to the fifth set.

[0184] In a possible implementation of the communication device 1100, the first field is also used to indicate that the degree of change in the channel state exceeds a threshold, including: the first field is used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state exceeds the threshold; or the first field is used to indicate the length of the first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state exceeds the threshold; or the first field is a second long training field, and the information carried on the subcarrier of the second long training field is used to indicate that the degree of change in the channel state exceeds the threshold; or the first field is used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state exceeds the threshold.

[0185] In a possible implementation of the communication device 1100, if the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state exceeds a threshold: the number of symbols in the first long training field is greater than NSTS; the number of symbols in the first long training field is greater than NSS; the number of symbols in the first long training field belongs to the sixth set; the number of symbols in the first long training field belongs to the seventh set, and the NSTS belongs to the eighth set; the number of symbols in the first long training field belongs to the ninth set, and the NSS belongs to the tenth set.

[0186] In a possible implementation of the communication device 1100, the first field is used to indicate the number of symbols of the first long training field, including: the first field is an NSTS field, and the NSTS field is used to indicate the number of symbols of the first long training field; or the first field is a Number of EHT-LTF Symbols field, and the Number of EHT-LTF Symbols field is used to indicate the number of symbols of the first long training field; or the first field is an NSTS And Midamble Periodicity field, and the NSTS And Midamble Periodicity field is used to indicate the number of symbols of the first long training field; or the first field includes an MCS field, and the MCS field is used to indicate the number of symbols of the first long training field; or the first field includes an MCS field and an STBC field, and the MCS field and the STBC field are used to indicate the number of symbols of the first long training field; or the first field includes an MCS field, an STBC field, and a NESS field, and the MCS field, the STBC field, and the NESS field are used to indicate the number of symbols of the first long training field.

[0187] In a possible implementation manner of the communication apparatus 1100 , the first PPDU is a Null Data Packet (NDP), or the first PPDU includes a Medium Access Control (MAC) frame.

[0188] In a possible implementation of the communication apparatus 1100 , the first PPDU includes a MAC frame, and the MAC frame further includes a level of change in the channel state.

[0189] It should be noted that the division of modules in the embodiments of the present application is illustrative and is merely a logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0190] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0191] It should be understood that the processing module 1201 in the embodiment of the present application can be implemented by a processor / processing circuit or a processor / processing circuit related circuit component, and the transceiver module 1202 can be implemented by a transceiver / transceiver interface or a transceiver / transceiver interface related circuit component or a communication interface.

[0192] like Figure 12A possible manifestation of the communication device provided in the embodiment of the present application. Device 1200 can be used to implement the method described in the above method embodiment. Among them, the communication device 1200 can be an AP or a STA, which can implement the functions of the first communication device or the second communication device in the method provided in the embodiment of the present application; the communication device 1200 can also be a device that can support the first communication device to implement the corresponding functions in the method provided in the embodiment of the present application, or a device that can support the second communication device to implement the corresponding functions in the method provided in the embodiment of the present application. Among them, the communication device 1200 can be a chip or a chip system. In the embodiment of the present application, the chip system can be composed of chips, or it can include chips and other discrete devices.

[0193] The communication device 1200 includes one or more processors / processing circuits 1201, which are used to implement or support the communication device 1200 in implementing the functions of the first communication device or the second communication device in the method provided in the embodiment of the present application, such as generating the aforementioned first PPDU. Optionally, the communication device 1200 may also include at least one memory 1203 for storing program instructions and / or data. The memory 1203 is coupled to the processor / processing circuit 1201. The coupling in the embodiment of the present application is an indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, for information exchange between devices, units or modules. The processor / processing circuit 1201 may operate in conjunction with the memory 1203. The processor / processing circuit 1201 may execute program instructions and / or data stored in the memory 1203 to enable the communication device 1200 to implement the corresponding method. At least one of the at least one memory may be located in the processor / processing circuit.

[0194] The communication device 1200 may further include a transceiver / transceiver interface 1202 for communicating with other devices via a transmission medium, so that the device in the communication device 1200 can communicate with other devices. The processor / processing circuit 1201 can use the transceiver / transceiver interface 1202 to transmit and receive data. The transceiver / transceiver interface 1202 can specifically be a transceiver / transceiver interface. The communication device 1200 may further include a radio frequency unit, which may be independent of the communication device 1200 or integrated within the communication device 1200. Of course, the above-mentioned transceiver / transceiver interface 1202 may further include an antenna, such as a remote antenna independent of the communication device 1200, or an antenna integrated within the communication device 1200.

[0195] In hardware implementation, the transceiver module 1002 may be a transceiver / transceiver interface 1202 .

[0196] The specific connection medium between the transceiver / transceiver interface 1202, the processor / processing circuit 1201 and the memory 1203 is not limited in the embodiment of the present application. Figure 12 The memory 1203, the processor / processing circuit 1201 and the transceiver / transceiver interface 1202 are connected via a bus. Figure 12 The connections between the other components are shown in bold lines, which are only for illustration and are not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, Figure 12 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0197] In the embodiments of the present application, the processor / processing circuit 1201 can be a general-purpose processor / processing circuit, a digital signal processor / processing circuit, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor / processing circuit can be a microprocessor / processing circuit or any conventional processor / processing circuit, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed by a hardware processor / processing circuit, or can be executed by a combination of hardware and software modules in the processor / processing circuit.

[0198] In an embodiment of the present application, the memory 1203 may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., or a volatile memory (volatile memory), such as a random-access memory (RAM). The memory is any other medium that can be used to carry or store a desired program code in the form of an instruction or data structure and can be accessed by a computer, but is not limited thereto. The memory in the embodiment of the present application may also be a circuit or any other device that can implement a storage function, for storing program instructions and / or data.

[0199] It should be noted that the communication device in the above embodiments can be a terminal or a circuit, or a chip used in a terminal or other combined devices, components, etc. with the above terminal functions. When the communication device is a terminal, the transceiver module can be a transceiver / transceiver interface, which can include an antenna and a radio frequency circuit, etc., and the processing module can be a processor / processing circuit, such as a central processing unit (CPU). When the communication device is a component with the above terminal functions, the transceiver module can be a radio frequency unit, and the processing module can be a processor / processing circuit. When the communication device is a chip or a chip system, the transceiver module can be the input and output interface of the chip or chip system, and the processing module can be the processor / processing circuit of the chip or chip system.

[0200] As a possible product form, the AP and STA described in the embodiments of the present application can also be implemented using the following: one or more FPGAs (field programmable gate arrays), PLDs (programmable logic devices), controllers, state machines, gate logic, discrete hardware components, any other suitable circuits, or any combination of circuits capable of performing the various functions described throughout this application.

[0201] In the embodiments of the present application, the first communication device can be either an AP or a STA. The second communication device can be either an AP or a STA. It should be understood that the various APs described above have any of the functions of the APs in the aforementioned method embodiments, and will not be further described here. Similarly, the various STAs described above have any of the functions of the STAs in the aforementioned method embodiments, and will not be further described here.

[0202] The embodiment of the present application also provides a communication system, specifically, the communication system includes a second communication device and a first communication device, or may also include more first communication devices and second communication devices. Exemplarily, the communication system includes a method for implementing the above Figure 6 The second communication device and the first communication device of the related functions.

[0203] The first communication devices are respectively used to implement the above Figure 6 The second communication device is used to implement the above Figure 6 The functions of the relevant second communication device. For example, the second communication device may perform Figure 6 In the embodiment shown in S601, S603 and S604, the first communication device may execute Figure 6 S601, S602 and S603 in the embodiment shown.

[0204] The present application also provides a computer-readable storage medium including instructions that, when executed on a computer, cause the computer to execute Figure 6A method performed by a first communication device or a second communication device.

[0205] The present application also provides a computer program product including computer program code, which, when executed on a computer, enables the computer to execute Figure 6 A method performed by a first communication device or a second communication device.

[0206] The embodiment of the present application provides a chip system, which includes a processor and may also include a memory, for implementing the functions of the first communication device or the second communication device in the aforementioned method. The chip system can be composed of a chip or include a chip and other discrete devices.

[0207] An embodiment of the present application further provides a communication device, including a processor and an interface; the processor is used to execute the communication method described in the above method embodiment.

[0208] It should be understood that the above-mentioned communication device can be a chip, and the processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor, which is implemented by reading the software code stored in the memory. The memory can be integrated into the processor or can be located outside the processor and exist independently.

[0209] An embodiment of the present application further provides a processing device, including a processor and an interface; the processor is used to execute the method described in the above method embodiment.

[0210] It should be understood that the above-mentioned processing device can be a chip, and the processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor, which is implemented by reading the software code stored in the memory. The memory can be integrated into the processor or can be located outside the processor and exist independently.

[0211] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When software is used for implementation, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website, computer, server or data center by wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode to another website, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a high-density digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0212] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0213] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0214] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0215] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0216] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0217] Through the description of the above embodiments, it will be clear to those skilled in the art that the present application can be implemented in hardware, firmware, or a combination thereof. When implemented using software, the above functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transmission of computer programs from one place to another. The storage medium can be any available medium that can be accessed by a computer. By way of example and not limitation, computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer. In addition, any connection can appropriately become a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwaves, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the fixing of the medium. As used herein, the terms "disk" and "disc" include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs. Disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of the above should also be included within the scope of protection for computer-readable media.

[0218] This application also provides the following:

[0219] (1) How to calculate the degree of CSI change?

[0220] In the present invention, the CSI change degree is compared with a threshold. If the sensing receiving end informs that the CSI change degree meets the threshold, then Met is fed back; otherwise, Not Met is fed back. For the sensing receiving end that feeds back Met, further feedback may be triggered later. The above threshold can be set by the sensing transmitter or the sensing initiator, and notified to the sensing receiving end by the sensing transmitter or the sensing initiator. The sensing initiator can be represented as the station that initiates a sensing session, and the sensing transmitter can be represented as the station that sends the PPDU for sensing measurement during the sensing period.

[0221] Here we will further explain how to calculate the CSI change degree: The previous calculation of the CSI change degree only talked about the CSI change degree can be obtained by comparing the current measured CSI with the previous CSI, that is, the input parameters are: the current measured CSI, the previous measured CSI. If the above meaning is expressed mathematically, it can be expressed as ΔCSI = f(CSI y ,CSI ins ), where ΔCSI represents the degree of CSI change; f(·) represents the method or formula for calculating the degree of CSI change; CSI y is the CSI measured previously; CSI ins is the CSI measured based on the current NDP (ins means instantaneous).

[0222] Here, the parameters for calculating the CSI change degree are further explained:

[0223] Method 1 for calculating the degree of CSI change:

[0224] ΔCSI=f(CSI y ,CSI ins ) Among them, CSI ins It is based on the CSI measured by the current NDP. y is the CSI measured previously. y It can be the last measured CSI, the average CSI, or a previously specified CSI.

[0225] Method 2 for calculating the degree of CSI change:

[0226] ΔCSI=a·g(CSI y1 ,CSI ins )+(1-a)·h(CSI y2 ,CSI ins )

[0227] Similarly, where CSI ins It is based on the CSI measured by the current NDP;

[0228] CSI y1 It can be the last measured CSI, the average CSI, or a previously specified CSI;

[0229] CSI y2 It can be the last measured CSI, the average CSI, or a previously specified CSI;

[0230] The value range of a is [0,1], which is intended for normalization. Other normalization methods can also be used.

[0231] For the above CSI variation, in one design, CSI y1 is the average CSI, CSI y2 is the last measured CSI. In this case, the CSI change degree may take into account both the CSI change degree compared with the average CSI and the CSI change degree compared with the last CSI. The weight of the considerations can be adjusted by a.

[0232] It should be understood that in the above two calculation methods, function f, function g, and function h may be the same or different.

[0233] The following examples illustrate the two calculation methods mentioned above:

[0234] The correlation is expressed as the normalized inner product of the two vectors, that is, the degree of change in CSI can be expressed as:

[0235]

[0236] Where ‖·‖ is the Euclidean norm, and h1 and h2 are vectors formed by the two measured CSI results.

[0237] Taking calculation method 1 as an example,

[0238]

[0239] Among them, h y It can indicate the last CSI measurement result, the average CSI measurement result, or the marked measurement result.

[0240] Taking calculation method 2 as an example,

[0241]

[0242] Among them, CSI is given here y1 Indicates the average CSI measurement result (h avg , avg here means average), and CSI y2 An example showing the last CSI measurement result (h pre , pre here means last time).

[0243] (2) How to calculate CSI in a multi-antenna scenario?

[0244] For single-antenna CSI measurement, the results of two CSI measurements can be represented by two vectors. Therefore, the CSI variation can be calculated using the two-vector evaluation method (such as the correlation calculation method using the product of normalized vectors). However, when the CSI is in matrix form (such as with multiple antennas), the two-vector evaluation method cannot be directly applied. In this case, the CSI variation can be calculated using the correlation matrix evaluation method. Alternatively, the CSI matrix can be converted to a CSI vector. There are many conversion methods, but this is just an example: to convert a 4*4 matrix to a 1*16 vector, simply place the jth column below the j-1th column (j>1). To convert a 4*4 matrix to a 16*1 vector, simply place the ith row after the i-1th row (i>1).

[0245] (3) Threshold adjustment method

[0246] CSI variation can be calculated using a unified formula or without a specific formula. This allows different devices to use different CSI variation calculation methods, facilitating personalized configuration. For example, devices with strong computing and storage capabilities can use a more accurate CSI variation calculation and evaluation method, while devices with weaker computing and storage capabilities can use a coarse CSI variation calculation and evaluation method.

[0247] Without defining a specific formula, in order to support setting a threshold to adjust the number of users that trigger CSI to meet a certain threshold, although there is no clear CSI evaluation formula, CSI evaluation and calculation should still follow certain rules, such as the following rules:

[0248] 1) The estimated CSI change degree needs to be normalized, such as to the range [0, 1];

[0249] 2) A larger calculated value of the CSI variation indicates a larger CSI variation (monotonically increasing, or strictly monotonically increasing);

[0250] 3) The calculated value of 0 for the CSI change degree indicates the minimum CSI change degree or no change;

[0251] 4) The calculated value of 1 of the CSI variation degree indicates that the CSI variation degree is the largest.

[0252] Or the following rules:

[0253] 1) The estimated CSI change degree needs to be normalized, such as to the range [0, 1];

[0254] 2) A larger calculated value of the CSI variation indicates a smaller CSI variation (monotonically decreasing, or strictly monotonically decreasing);

[0255] 3) The calculated value of 0 for the CSI change degree indicates the maximum CSI change degree (monotonically decreasing);

[0256] 4) A calculated value of 1 for the CSI change degree indicates that the CSI change degree is minimal or there is no change (when monotonically decreasing).

[0257] By specifying the above rules, the number of users reporting Met can be adjusted by setting a larger threshold. For example, if the evaluation rule is defined as monotonically increasing, a larger threshold can be set to represent a greater threshold for CSI change, reducing the number of users subsequently triggered (increasing the number of users reporting Not Met). Alternatively, a smaller threshold can be set to increase the number of users reporting Met. The above calculated value can also be expressed as an evaluation value, an estimate, etc., which all represent the same meaning, namely, reflecting the degree of CSI change.

[0258] In short, the above description is only a preferred embodiment of the technical solution of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Claims

1. A communication method, characterized in that: Chips used in or within the sensing receiver include: generating a first physical layer protocol data unit (PPDU), wherein the first PPDU includes a MAC frame, wherein the MAC frame is used to indicate a degree of change in a channel state; and the degree of change in the channel state is used for sensing. Sending the first PPDU to the sensing sending end; receiving a second PPDU from the perception sending end, where the second PPDU is used to trigger the perception receiving end to provide feedback; When the degree of change of the channel state exceeds a threshold, the channel measurement result is sent to the sensing sending end.

2. The method according to claim 1, wherein The first PPDU includes a first field, where the first field is used to indicate whether the degree of change in the channel state exceeds a threshold or does not exceed the threshold.

3. The method according to claim 2, wherein The first field is used to indicate that the degree of change in the channel state does not exceed the threshold, including: The first field is used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not exceed a threshold; or The first field is used to indicate the length of a first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state does not exceed a threshold; or The first field is a second long training field, and information carried on a subcarrier of the second long training field is used to indicate that a degree of change in a channel state does not exceed a threshold; or The first field is used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state does not exceed a threshold.

4. The method according to claim 2, wherein The first field is used to indicate that the degree of change in the channel state does not exceed the threshold, including: The first field includes negative confirmation information, where the negative confirmation information is used to indicate that the degree of change in the channel state does not exceed a threshold.

5. The method according to claim 3, wherein If the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state does not exceed the threshold: The number of symbols in the first long training field is less than the number of space-time streams NSTS; The number of symbols in the first long training field is less than the number of spatial streams NSS; The number of symbols of the first long training field belongs to a first set; The number of symbols of the first long training field belongs to a second set, and the NSTS belongs to a third set; The number of symbols of the first long training field belongs to a fourth set, and the NSS belongs to a fifth set.

6. The method according to claim 2, wherein The first field is also used to indicate that the degree of change in the channel state exceeds a threshold, including: The first field is used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state exceeds a threshold; or The first field is used to indicate the length of a first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state exceeds a threshold; or The first field is a second long training field, and information carried on a subcarrier of the second long training field is used to indicate that a degree of change in a channel state exceeds a threshold; or The first field is used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state exceeds a threshold.

7. The method according to claim 6, wherein If the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state exceeds a threshold: The number of symbols in the first long training field is greater than NSTS; The number of symbols in the first long training field is greater than NSS; The number of symbols in the first long training field belongs to a sixth set; The number of symbols of the first long training field belongs to a seventh set, and the NSTS belongs to an eighth set; The number of symbols of the first long training field belongs to a ninth set, and the NSS belongs to a tenth set.

8. The method according to claim 3 or 6, wherein: The first field is used to indicate the number of symbols of the first long training field, including: The first field is an NSTS field, and the NSTS field is used to indicate the number of symbols of the first long training field; or The first field is an ultra-high throughput long training field symbol number (EHT-LTF Symbols) field, where the EHT-LTF Symbols field is used to indicate the number of symbols in the first long training field; or The first field is an NSTS and Midamble Periodicity field, where the NSTS and Midamble Periodicity field is used to indicate the number of symbols in the first long training field; or The first field includes a modulation and coding strategy (MCS) field, where the MCS field is used to indicate the number of symbols in the first long training field; or The first field includes an MCS field and a space-time block coding (STBC) field, where the MCS field and the STBC field are used to indicate the number of symbols in the first long training field; or The first field includes an MCS field, an STBC field, and an extended spatial stream number NESS field, and the MCS field, the STBC field, and the NESS field are used to indicate the number of symbols of the first long training field.

9. The method according to any one of claims 1 to 7, wherein: The evaluation of the degree of change in the channel state satisfies the following rules: The estimated channel state information (CSI) variation is normalized to the range [0, 1]. A larger calculated value of the CSI variation degree indicates a larger CSI variation degree; The calculated value of 0 for the CSI change degree indicates that the CSI change degree is minimal or there is no change; The calculated value of 1 of the CSI variation degree indicates that the CSI variation degree is the largest.

10. The method according to any one of claims 1 to 7, wherein: Also includes: A second PPDU is received, where the second PPDU is used to indicate that feedback is to be performed when the degree of change in the channel state does not exceed a threshold, and / or the second PPDU is used to indicate that feedback is to be performed when the degree of change in the channel state exceeds a threshold.

11. The method according to any one of claims 1 to 7, wherein: In the case where multiple sensing receiving ends perform feedback simultaneously, the multiple sensing receiving ends are distinguished by using spatial streams, or by using orthogonal frequency division multiple access (OFDMA).

12. A communication method, characterized in that: Chips used in or within the sensing transmitter include: receiving a first physical layer protocol data unit (PPDU) from a sensing receiving end, where the first PPDU includes a MAC frame, where the MAC frame is used to indicate a degree of change in a channel state; and the degree of change in the channel state is used for sensing; determining, according to the first PPDU, that a degree of change in the channel state exceeds a threshold; Sending a second PPDU to the sensing receiving end, where the second PPDU is used to trigger the sensing receiving end to provide feedback; Receive a channel measurement result from the sensing receiving end.

13. The method according to claim 12, wherein: The first PPDU includes a first field, where the first field is used to indicate whether a degree of change in the channel state exceeds a threshold or does not exceed a threshold; The method further comprises: According to the first field, it is determined whether the degree of change in the channel state exceeds a threshold.

14. The method according to claim 13, wherein The first field is used to indicate that the degree of change in the channel state does not exceed the threshold, including: The first field is used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state does not exceed a threshold; or The first field is used to indicate the length of a first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state does not exceed a threshold; or The first field is a second long training field, and information carried on a subcarrier of the second long training field is used to indicate that a degree of change in a channel state does not exceed a threshold; or The first field is used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state does not exceed a threshold.

15. The method according to claim 13, wherein The first field is used to indicate that the degree of change in the channel state does not exceed the threshold, including: The first field includes negative confirmation information, where the negative confirmation information is used to indicate that the degree of change in the channel state does not exceed a threshold.

16. The method according to claim 14, wherein If the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state does not exceed the threshold: The number of symbols in the first long training field is less than the number of space-time streams NSTS; The number of symbols in the first long training field is less than the number of spatial streams NSS; The number of symbols of the first long training field belongs to a first set; The number of symbols of the first long training field belongs to a second set, and the NSTS belongs to a third set; The number of symbols of the first long training field belongs to a fourth set, and the NSS belongs to a fifth set.

17. The method according to claim 13, wherein The first field is also used to indicate that the degree of change in the channel state exceeds a threshold, including: The first field is used to indicate the number of symbols in the first long training field, and the number of symbols in the first long training field is used to indicate that the degree of change in the channel state exceeds a threshold; or The first field is used to indicate the length of a first padding field, and the length of the first padding field is used to indicate that the degree of change in the channel state exceeds a threshold; or The first field is a second long training field, and information carried on a subcarrier of the second long training field is used to indicate that a degree of change in a channel state exceeds a threshold; or The first field is used to indicate the size of the third long training field, and the size of the third long training field is used to indicate that the degree of change in the channel state exceeds a threshold.

18. The method according to claim 17, wherein If the number of symbols in the first long training field satisfies any of the following conditions, it is used to indicate that the degree of change in the channel state exceeds a threshold: The number of symbols in the first long training field is greater than NSTS; The number of symbols in the first long training field is greater than NSS; The number of symbols in the first long training field belongs to a sixth set; The number of symbols of the first long training field belongs to a seventh set, and the NSTS belongs to an eighth set; The number of symbols of the first long training field belongs to a ninth set, and the NSS belongs to a tenth set.

19. The method according to claim 14 or 17, wherein: The first field is used to indicate the number of symbols of the first long training field, including: The first field is an NSTS field, and the NSTS field is used to indicate the number of symbols of the first long training field; or The first field is an ultra-high throughput long training field symbol number (EHT-LTF Symbols) field, where the EHT-LTF Symbols field is used to indicate the number of symbols in the first long training field; or The first field is an NSTS and Midamble Periodicity field, where the NSTS and Midamble Periodicity field is used to indicate the number of symbols in the first long training field; or The first field includes a modulation and coding strategy (MCS) field, where the MCS field is used to indicate the number of symbols in the first long training field; or The first field includes an MCS field and a space-time block coding (STBC) field, where the MCS field and the STBC field are used to indicate the number of symbols in the first long training field; or The first field includes an MCS field, an STBC field, and an extended spatial stream number NESS field, and the MCS field, the STBC field, and the NESS field are used to indicate the number of symbols of the first long training field.

20. The method according to any one of claims 12 to 18, wherein: The evaluation of the degree of change in the channel state satisfies the following rules: The estimated channel state information (CSI) variation is normalized to the range [0, 1]. A larger calculated value of the CSI variation degree indicates a larger CSI variation degree; The calculated value of 0 for the CSI change degree indicates that the CSI change degree is minimal or there is no change; The calculated value of 1 of the CSI variation degree indicates that the CSI variation degree is the largest.

21. The method according to any one of claims 12 to 18, wherein: Also includes: Send a second PPDU, where the second PPDU is used to indicate that feedback is to be performed when the degree of change in the channel state does not exceed a threshold, and / or the second PPDU is used to indicate that feedback is to be performed when the degree of change in the channel state exceeds a threshold.

22. The method according to claim 21, wherein In the case where multiple perception receiving ends perform the feedback simultaneously, the multiple perception receiving ends are distinguished by using spatial streams, or by using orthogonal frequency division multiple access (OFDMA).

23. A communication device, characterized in that: The communication device comprises means for performing the method according to any one of claims 1-22.

24. A computer-readable storage medium, characterized in that The invention comprises a computer program or an instruction which, when executed on a computer, causes the method according to any one of claims 1 to 22 to be performed.

25. A computer program product, characterized in that When the method is executed on a computer, the method according to any one of claims 1 to 22 is executed.

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