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: 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: 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: A method for sensing sneezing based on a wireless signal includes obtaining a wireless signal, where the wireless signal propagates in space including a first object. Doppler estimation is performed on the wireless signal, to obtain Doppler information of the wireless signal. The Doppler information of the wireless signal may be used for indicating impact of the first object on a frequency of the wireless signal. Whether the first object is sneeze droplets is determined based on the Doppler information of the wireless signal.

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: 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 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.