Abstract: A method includes, in accordance with some implementations, sending, a measurement station, a trigger frame to a signal source station, where the trigger frame carries pilot format information, and the pilot format information is used to indicate a sending time point of a signal frame triggered by the trigger frame, a quantity of times for sending the signal frame, and a transmission mode of pilot information in the signal frame. The measurement station receives an illumination frame from the signal source station, where the illumination frame is the signal frame triggered by the trigger frame. The measurement station analyzes pilot information in the illumination frame to obtain sensing information in the illumination frame, where the sensing information is used to indicate physical information of an object surrounding the signal source station and the measurement station.

Abstract: In a sensing session establishment process, an access point sends a first frame to a first station, where the first frame includes first information, the first information indicates a first role of the first station in a sensing session, the first role of the first station in the sensing session is a transmitter and/or a receiver, and the first station is a station participating in the sensing session in a second station associated with the access point; and the access point receives a second frame from the first station, where the second frame includes confirm information for the first frame.

Abstract: A sensing result feedback method, an apparatus, a device, and a medium are provided. In an example method, a sensing initiating device sends an indication about truncation and feedback of a time domain channel estimation and sensing sequence to a first sensing responding device. The first sensing responding device truncates the received time domain channel estimation and sensing sequence based on the indication, and feeds back the truncated time domain channel estimation and sensing sequence. Therefore, a sensing sender may perform channel estimation and target sensing based on the truncated time domain channel estimation and sensing sequence. In this manner, feedback overheads can be significantly reduced, and sensing performance can be ensured to some extent.

Abstract: Embodiments of this application provide a communication method and apparatus, to improve robustness of a communication process and improve accuracy of a sensing result. The communication method includes: generating a first physical layer protocol data unit (PPDU), where the first PPDU includes a first field that indicates that a variation of a channel state does not exceed a threshold; and sending the first PPDU.

Abstract: This application discloses a signal processing method and an apparatus. The method includes: A transmit device generates a PPDU, and sends the PPDU; and a receive device receives the PPDU, and processes M sequences carried in the PPDU. The PPDU shown in this application includes a first field, the first field is used for carrying M sequences, the M sequences correspond to M space-time streams, one sequence corresponds to one space-time stream, and M is a positive integer. According to the method provided in this application, sequence sending efficiency can be effectively improved.

Abstract: A data transmission method. A physical layer protocol data unit (PPDU) is generated. The PPDU includes a training field. The training field includes a sequence used for target sensing. The PPDU is sent.

Abstract: Provided are a method for performing feedback based on channel state information (CSI), a device, and a medium. In an example method, a sensing response device obtains CSI data based on channel estimation, and generates power delay profile (PDP) data based on the CSI data. Then, the sensing response device feeds back a part of PDP data in the generated PDP data. Therefore, feedback overheads are reduced. In addition, sensing performance is ensured to some extent.

Abstract: A method for sending a measurement packet and a communication apparatus. The method includes: a first wireless device sends a trigger frame, where the trigger frame is used to trigger a plurality of second wireless devices to send measurement packets in an orthogonal frequency division multiple access (OFDMA) manner; and the first wireless device receives the measurement packets sent by the plurality of second wireless devices in the OFDMA manner. Based on the method, the measurement packet sent by each second wireless device occupies only some tones of an uplink transmission bandwidth. This improves power spectral density of the measurement packet and improves precision of measuring channel information by the first wireless device.

Abstract: This application provides a method and an apparatus for sensing measurement. In a technical solution of this application, a transmit end of data may send an indication frame to a receive end of the data, where the indication frame may indicate a spatial mapping matrix used by the transmit end of the data to send the data to the receive end of the data. In this way, the receive end of the data can eliminate impact of spatial mapping on channel state information based on the spatial mapping matrix, to obtain actual channel state information, thereby completing sensing, positioning, and the like on an ambient environment or a passive target by using the obtained actual channel state information.

Abstract: A method includes: A first device sends a first BRP frame, to indicate a second device to evaluate a variation of CSI from the first device to the second device in an initiator beam refinement protocol transmit sector sweep procedure. The first device sends a plurality of first BRP-TX PPDUs, where the plurality of first BRP-TX PPDUs are used to evaluate the variation of the CSI from the first device to the second device. The first device receives a second BRP frame carrying a first sector information list, where the first sector information list is used to feed back one or more sending sectors whose variation of the CSI from the first device to the second device is greater than a CSI variation threshold.

Abstract: A channel information feedback method. The method can be applied to a first wireless device, and includes: receiving a first message from a second wireless device, where the first message notifies channel information measurement, the first message carries first indication information related to the first wireless device, and the first indication information indicates a feedback condition; performing channel information measurement based on the first message; determining a first channel information variation based on currently measured channel information and historically measured channel information; and feeding back a measurement report to the second wireless device when the first channel information variation meets the feedback condition.

Abstract: This application provides a sensing measurement information exchange apparatus, applied to a first station. The apparatus includes: a transceiver unit, configured to receive sensing measurement report information sent by a second station, where the sensing measurement report information includes N groups of first measurement results, where the N groups of first measurement results are in a one-to-one correspondence with N first transmission paths between the first station and the second station, and each group of first measurement results includes an angle of arrival, relative time of flight, and a Doppler frequency shift of a corresponding first transmission path; and a processing unit, configured to obtain angles of arrival, relative time of flight, and Doppler frequency shifts of the N first transmission paths based on the sensing measurement report information. This application implements measurement of locations and instantaneous speeds of a plurality of passive targets.

Abstract: A data frame sending method includes: encoding first information by using a first encoder, to generate a first coded segment and a second coded segment; interleaving the first information by using M interleavers, to generate M pieces of information, where the M pieces of information one-to-one correspond to the M interleavers; encoding the M pieces of information by using the first encoder, to generate 2M coded segments; generating a data frame, where the data frame includes N coded segments, and the N coded segments include all or a portion of the first coded segment, the second coded segment, and the 2M coded segments; and sending the data frame through at least two subchannels in N subchannels.

Abstract: This application discloses a data transmission method that includes: scrambling to-be-transmitted data, to obtain scrambled data; and sending the scrambled data to a receive device. The initialization bits of a scrambler used to scramble the data include a first bit sequence and a second bit sequence. The first bit sequence is carried in a service field of the to-be-transmitted data, the second bit sequence reuses a bit in a signal field of a physical layer protocol data unit (PPDU), and the quantity of the initialization bits is equal to the order of the scrambler. In embodiments of this application, when the transmit device and the receive device use the scrambler with a higher order than that in the conventional technology, the initialization bits of the scrambler are based on bits in an existing service field used for data scrambling and reused bits in some signal fields.

Abstract: This provides a spatial multiplexing method and apparatus, to introduce WLAN sensing into a conventional spatial multiplexing mechanism and improve communication efficiency. The method includes: An AP sends a first request message to a first station and a second station, to request to measure channel quality in one or more sensing beam directions in a first SP; the AP sends a second request message to a third station and a fourth station, to request to measure channel quality in a communications beam direction in a second SP; the first station, the second station, the third station, and the fourth station separately perform measurement and report respective first measurement results; and the AP receives the first measurement results of the stations, and determines, based on the first measurement results, whether to perform spatial multiplexing on the first SP and the second SP.

Abstract: A wireless local area network sensing method. The method includes: in a process in which a second network device performs high frequency MIMO channel access, a first network device sends indication information to a plurality of second network devices, where the indication information indicates the plurality of second network devices to send uplink sensing signals; and the first network device receives the uplink sensing signals from the second network devices and performs uplink sensing based on the uplink sensing signals.

Abstract: A method includes: A first node sends a threshold and a first packet to a second node. Correspondingly, the second node receives the threshold and the first packet from the first node. Then, the second node determines first channel state information CSI based on the first packet. If a change amount of the first CSI relative to preset CSI exceeds the threshold, the second node sends a second packet to the first node. If the change amount of the first CSI relative to the preset CSI does not exceed the threshold, the second node does not need to send the second packet to the first node. The method is applied to a radio sensing process.

Abstract: This application provides example object locating methods and apparatuses. One example method includes performing, by a first device, pulse measurement on a target object with assistance of a second device, where the pulse measurement is performed on the target object by using two types of pulse signals, and pulse repetition frequencies of the two types of pulse signals are different. The first device can then locate the target object based on a pulse measurement result of the pulse measurement.

Abstract: The disclosure provides ranging methods and apparatuses. One example method includes that a first device sends a first signal on a first channel. The first device receives, on a second channel, a second signal from a second device, where the second signal is a signal obtained after frequency conversion is performed on the first signal. The first device calculates a distance between the first device and the second device based on a phase difference between carriers of the second signal.

Abstract: A first device sends a first message to a second device, where the first message indicates to the second device to hop to different channels at different times to send radio signals. The frequency bandwidth ranges of any two channels do not completely overlap, and the frequency bandwidth range of each channel is within a total frequency bandwidth range supported by the first device. The first device separately receives the radio signals that are sent by the second device on different channels at different times. The radio signals reach the first device after being reflected by an intermediate object. The first device measures the state information of the intermediate object based on the physical characteristics of the different radio signals that are separately received.