The invention discloses a wireless signal Doppler frequency shift method for determining moving object direct reflection. The wireless signal Doppler frequency shift method can use channel state information on two antennas (namely CSI) to perform conjugate multiplying to eliminate random phase shift caused by non-synchronous wireless transmit-receive devices, and can obtain complete Doppler frequency shift information from the phase information of the channel state information which includes sizes and directions. The wireless signal Doppler frequency shift method for determining moving object direct reflection eliminates interference on the Doppler shift which is caused by frequency information of a static path so as to obtain more accurate frequency estimation. The wireless signal Doppler frequency shift method for determining moving object direct reflection can use multiple signal classification algorithm (MUSIC) to estimate a frequency spectrum according to a practical sampling interval and avoid an effect on the frequency estimation accuracy which is caused by uniform sampling by the practical wireless transmit-receive system.

Wireless signal Doppler frequency shift method for determining moving object direction reflection

The invention provides an indoor positioning method and system based on wireless receiving equipment and a camera and belongs to the field of positioning technologies. The method comprises the following steps that the wireless receiving equipment detects a query WIFI signal transmitted by target equipment; the wireless receiving equipment extracts an MAC address of the target equipment and channel state information from the query WIFI signal; a server captures the MAC address of the target equipment and the channel state information from the wireless receiving equipment, computes an angle of incidence between the target equipment and the wireless receiving equipment and sends a shooting instruction to the camera simultaneously, the camera takes an image and uploads the image to the server; and the server obtains a distance between the wireless receiving equipment and the target equipment through image pixels and computes position information of the target equipment according to coordinates of the wireless receiving equipment. According to the method and the system, the accurate positioning of the target equipment can be realized by only one wireless receiving equipment and one camera, so that the cost is controlled and the computation real-time performance is guaranteed; and a good positioning effect is obtained through combination of the wireless receiving equipment and the camera.

Indoor positioning method and system based on wireless receiving equipment and camera

The invention relates to a high-reliable user behavior identification method based on wireless sensing. The method comprises the following steps: via a wireless sensing technology, collecting channelstate information data of a body action in real time, performing low-pass filtering on the data, removing high-frequency noise, enhancing data quality, reducing static path influence on the data, removing the high-light effect, solving a shielding problem, and applying the denoising method based on the principal component analysis on the data so as to reduce the influence of the primary noise; intercepting the time-series waveform to extract the action waveform, performing feature value computation on the extracted waveform to obtain a feature vector, and depicting the user action by using thefeature vector, and identifying six actions of an experimental user by using a SMO classification method. Based on the CSI information, the sitting, the standing after the sitting, the squatting, thestanding after the squatting, the walking and the running of each user can be identified, a period of action sequence data is collected, and the action can be precisely identified by using the identification model.

High-reliable user behavior identification method based on wireless sensing

The invention discloses a CSI-based Wi-Fi single access point distance measurement positioning method and system, an electronic device and a computer storage medium. The CSI-based Wi-Fi single accesspoint distance measurement positioning method is characterized by applying to a Wi-Fi network comprising a transmitting end and a receiving end, wherein the transmitting end comprises a single accesspoint; and the method comprises the following steps: the transmitting end receives a positioning application sent by the receiving end, and appoints a frequency hopping control protocol and a frequency hopping time of the both parties with the receiving end; and according to the frequency hopping control protocol and the frequency hopping time, any one of the transmitting end and the receiving endsends a pilot signal, and the other end receives CSI data and obtains a positioning result accordingly, wherein the transmitting end and the receiving end respectively have at least three antennas. According to the CSI-based Wi-Fi single access point distance measurement positioning method and system disclosed by the invention, the location of the receiving end can be determined without rotatingthe receiving end, so that the operation is convenient, and the positioning accuracy is high.

CSI-based Wi-Fi single access point distance measurement positioning method and system, and electronic device

The invention discloses a method for restoring a moving track of a hand in the air by using a radio signal, which is free from a special sensor and is used for detecting and restoring a writing trackof a finger in the air by using the radio signal of existing communication equipment. One signal transmitting device Tx and two signal receiving devices Rx are placed, each receiving device is provided with at least two antennas, and no barrier exists between the Tx and the Rx. The hand does not need to wear any equipment. The moving area of the hand in air is interior of a square area defined byTx-Rx1 and Tx-Rx2. A radio signal is disturbed by using the movement of the hand, wireless channel changes on a plurality of receiving antennas are measured and extracted, and then the movement trackof the hand in the air is calculated. According to the method, the channel CSI value acquired by the existing wireless communication equipment is utilized, and extra hardware equipment or hardware change is not needed, so that the cost is saved. The application range is wide. Accurate tracking can be carried out, and the track restoration precision is high. Real-time continuous operation can be achieved, and convenience and practicability are achieved.

Method for restoring moving track of hand in air by using radio signal

The invention discloses a non-contact perceptive positioning method A transmitting end is WiFi signal transmitting equipment; a receiving end is a WiFi signal receiver corresponding to the transmitting end; an antenna array is constructed to receive signals; based on the difference between antennas, and by utilization of signal coherence, the arrival angle of a reflected signal of a moving target is identified; simultaneously, the relative lengths of various reflection paths of the dynamic target are estimated by utilizing the difference between carriers having different frequencies; and the arrival angle of a signal of one of the reflection paths is selected and used as the angle of the positioning target relative to receiving equipment According to the non-contact perceptive positioning method disclosed by the invention, the positioning target does not need to carry any equipment; accurate non-contact perceptive positioning of a dynamic object can be realized by utilizing a WiFi network card; the position of the target can be determined by only needing one WiFi transmitting end and two WiFi receiving ends at least; the missing measurement value is complemented by utilizing the spatial and time continuities of movement simultaneously; and thus, the perceptible range is enlarged

Non-contact perceptive positioning method

The invention discloses an indoor activity detection method and system. The indoor activity detection method comprises the following steps: receiving wireless signals at two receiving points to obtainchannel state information; making difference between the phases in the channel state information of the two receiving points to obtain a phase difference signal sequence, and then performing interpolation processing on the phase difference; performing band-pass filtering on the phase difference after the interpolation processing; extracting features from the phase difference signal after the band-pass filtering, and calculating the standard deviation of the phase difference that the signal sequence is normalized through the manner of sliding window; and judging whether an activity exists in the current environment or not according to the standard deviation. According to the indoor activity detection method, the real-time mobile behavior detection can be realized by means of a commercial WiFi network card; and when the environment changes, the indoor activity detection method can automatically adapt to the environmental changes through the manner of self-learning without manual assistance; in addition, a number of novel processing mechanisms are provided by the invention to eliminate the interference caused by common scenes in life, therefore, the robustness of the mobile behaviordetection method is increased in general.

Indoor activity detection method and system

The invention discloses a moving object-reflected wireless signal identifying method. An emitting end in a wireless transmission environment is a wireless signal emitting device, and a receiving end in the wireless transmission environment is a wireless signal receiver corresponding to the emitting end. The moving object-reflected wireless signal identifying method is characterized in that devices at the wireless signal emitting end and the wireless signal receiving end are not required, signals can be received via an antenna array of the wireless signal receiving end, a direct path signal and a static object reflection path signal are combined into a static path signal via a signal processing method, an arrival angle of the static path signal and an arrival angle of a moving object reflection path signal can be automatically identified in signal identifying processes, and therefore a moving object-reflected wireless signal can be identified. A technical solution of the moving object-reflected wireless signal identifying method is low in equipment requirements, hardware change is not required, the method can be implemented in common commercial wireless equipment, rapid and convenient implementation can be achieved, and low cost and high benefits can be realized.

Moving object-reflected wireless signal identifying method

The invention discloses a contactless fitness exercise monitoring method. The method comprises the steps that receiving equipment with at least two antennas receives signals from transmitting equipment with at least one antenna in a wireless transmission mode; channel state information (CSI) of wireless transmission is measured, a CSI signal stream, a Doppler velocity flow and a Doppler shift floware obtained by processing the CSI; cutting is carried out on movement based on the obtained Doppler shift flow; based on cutting of the movement, classification features are extracted from the CSI signal flow, the Doppler velocity flow and the Doppler shift flow; the movement is classified based on the classification features to determine the type of the fitness exercise.

Unarmed fitness exercise monitoring method without contact perception

A method for identifying a wireless signal reflected by a moving object, wherein a transmitting end in a wireless transmission environment is a wireless signal transmitting device, and a receiving end is a wireless signal receiver corresponding to the transmitting end; and it is unnecessary to modify wireless signal transmitting end and receiving end devices, a signal is received by means of an antenna array of a wireless signal receiving end, a direct path signal and a static object reflection path signal are combined into a static path signal by means of a signal processing method, an angle of arrival of the static path signal and an angle of arrival of a signal on a moving object reflection path are automatically identified in a signal identification process, thereby identifying a wireless signal reflected by a moving object.

Li Shengjie

Papers

Non-contact perceptive positioning method

Indoor activity detection method and system

Moving object-reflected wireless signal identifying method

Unarmed fitness exercise monitoring method without contact perception

Method for identifying a wireless signal reflected by moving object