A direct line-of-sight (DLOS) radio frequency (RF) signal component and a reflected RF signal component of an RF carrier signal are received from a transmitter. The reflected component is reflected from a point on the surface of the earth. The DLOS component is converted to a digital DLOS intermediate frequency (IF) signal and the reflected component that is converted to a digital reflected IF signal. Modeled reference signal parameters are generated using the digital DLOS IF signal and known locations of the one or more antennas, the transmitter, and the point. A reference signal is generated based on the modeled reference signal parameters and feedback of a previously estimated phase correction (Δϕ). The reference signal is correlated with the digital reflected IF signal to produce in-phase and quadrature-phase correlation results. Estimated carrier-to-noise ratio (C/N.sub.0) and Δϕ values are calculated for the digital reflected IF signal from the correlation results.

A method for active neutralization of the effect of the vibrations of a rotary-wing aircraft for a monostatic Doppler radar includes a first step of measuring and temporally extrapolating the vibration modes at the transmitting-receiving radar antenna, using a 3-axis vibration sensor, fixed to the antenna and near the phase centre of the antenna; then a second step of estimating the expected movements of the transmitting-receiving antenna or of the first transmitting antenna and the second receiving antenna; then a third step of compensating the expected movements of the transmission radar antenna in the transmission chain or in the reception chain of the radar transmitter, wherein the projection of the movement vector of the phase centre O on an aiming direction is calculated to determine the value of the compensation phase shift to be applied.

According to embodiments, a radar system includes: at least one radio receiver which is comprised of: an antenna configured to receive RF data including both the direct-path RF signal transmitted from a radio transmitter and a reflected RF signal when the transmitted RF signal is reflected from the target; a memory configured to store the same predetermined RF waveform profile data used by the transmitter to generate and transmit the RF signal; a timing unit to provide timing; a matched filter application configured to generate and apply a matched filter for identifying RF signal signatures in RF data; and one or more processors configured to: (i) analyze the received RF data to identify multiple, repeated, individual RF signals corresponding to the direct-path transmitted RF signal; (ii) split the identified RF signals corresponding to the direct-path transmitted RF signal into a plurality of repeating units each having an interval time; (iii) create a matched filter using the predetermined transmit waveform (stored in memory) and apply the matched filter to each of repeating units to provide (a) a plurality of direct-path transmitted RF signal arrival times; and (b) a plurality of reflected RF signal arrival times; (iv) adjust relative arrival times and phases of the repeating units of the direct-path transmitted RF signal; and (v) generate radar data from the reflected RF signal further using the adjusted times and phases for arrival times of the repeating units of the direct-path transmitted RF signal.

Systems and methods for dynamic channel representations are described. Initially a sensing receiver receives a sensing transmission. The sensing receiver then generates a sensing measurement based on the sensing transmission. Thereafter, the sensing receiver generates a channel representation information of a propagation channel between the sensing receiver and a sensing transmitter based on the sensing measurement. The sensing receiver then obtains a sensing imprint representing a steady-state propagation channel between the sensing receiver and the sensing transmitter. Further, the sensing receiver compares the channel representation information to the sensing imprint and identifies a difference between the channel representation information and the sensing imprint. The sensing receiver may further send the channel representation information to a sensing algorithm manager.

The present disclosure relates to a system and method for detecting an object abnormality symptom based on a radar micro-Doppler. The system for detecting an object abnormality symptom based on a radar micro-Doppler includes a multiple input multiple output (MIMO) system configured to determine whether an object has a suspicious abnormality symptom by collecting information of the object and a beamforming antenna system configured to form an antenna radiation beam toward the object based on a result of the determination for the object having the suspicious abnormality symptom and to obtain three-dimensional (3D) micro-Doppler information.

Disclosed is an information processing system configured to use radio waves to sense an action of a user who operates a device. The information processing system includes one or more processors; and a memory storing a computer-readable program having instructions, which when executed by the one or more processors, cause the one or more processors to execute a process, the process including acquiring a state of radio waves in an area where a device is installed; receiving information from the device, the information indicating that a predetermined event has been detected; and notifying that the predetermined event has occurred at the device, based on a state of radio waves acquired during a predetermined period before the predetermined event and the acquired state of radio waves.

A method includes receiving a first wireless signal detected by a first device in an environment, the first wireless signal including a first distortion pattern caused by an object moving in the environment, receiving a second wireless signal detected by a second device in the environment, the second wireless signal including a second distortion pattern caused by the object moving in the environment, determining, by comparing the first distortion pattern to the second distortion pattern, that the first distortion pattern and the second distortion pattern correspond to a same movement event associated with the object moving in the environment, determining a timing offset between the first device and the second device based on information associated with the first distortion pattern and the second distortion pattern, and determining, based on the timing offset, temporal correspondences between data generated by the first device and data generated by the second device.

One of a transmitting array antenna and a receiving array antenna includes a first antenna group and a second antenna group. The first antenna group includes one or more first antenna elements of which the phase centers of the antenna elements are laid out at each first layout spacing following a first axis direction, and a shared antenna element. The second antenna group includes a plurality of second antenna elements and the one shared antenna element, and the phase centers of the antenna elements are laid out in two columns at each second layout spacing following a second axis direction that is different from the first axis direction. The phase centers of the antenna elements included in each of the two columns differ from each other regarding position in the second axis direction.

Techniques are provided for managing transmit and receive beams in a millimeter wave (mmW) communication system for use in bistatic radio frequency (RF) sensing. An example method of tracking targets with bistatic radio frequency sensing includes receiving one or more sensing reference signals, generating a signal report based at least in part on the one or more sensing reference signals, transmitting the signal report, receiving tracking signal configuration information, receiving one or more tracking reference signals identified in the tracking signal configuration information, and tracking one or more targets associated with the one or more tracking reference signals.

Methods, apparatus and systems for movement tracking are described. In one example, a described system comprises: at least one sensor configured to generate at least one sensing information (SI); a memory; a processor communicatively coupled to the memory and the at least one sensor; and a set of instructions stored in the memory. The set of instructions, when executed by the processor, cause the processor to: obtain at least one time series of SI (TSSI) from the at least one sensor, analyze the at least one TSSI, track a movement of an object in a venue based on the at least one TSSI, compute an incremental distance associated with the movement of the object in a first incremental time period based on the at least one TSSI, compute a direction associated with the movement of the object in a second incremental time period based on the at least one TSSI, and compute a next location of the object at a next time based on at least one of: a current location of the object at a current time, a current orientation of the object at the current time, the incremental distance, the direction, or a map of the venue.