In various examples, methods and systems are provided for sampling and transmitting the most useful information from a radar signal representing a scene while staying within the computational and storage confines of a standard automotive radar sensor and the bandwidth constraints of a standard communication link between a radar sensor and processing unit. Disclosed approaches may select a patch of frequency bins that correspond to radar signals based at least on proximities of the frequency bins to one or more frequency bins corresponding to at least one peak and/or detection point in the radar signals. Data representing samples corresponding to the patch of frequency bins may be transmitted to the processing unit and applied to one or more machine learning models in order to accurately classify, identify, and/or track objects.

An operation method performed by an apparatus for detecting multiple targets may comprise transmitting first signals using M.sub.t transmit antennas included in the apparatus; receiving the first signals reflected by the multiple targets through M.sub.r receive antennas included in the apparatus; generating a first function for estimating a velocity and an azimuth of each of the multiple targets using the first signals and the reflected first signals; estimating a velocity and an azimuth that maximize a result of the first function as a velocity and an azimuth of a first target closest to the apparatus among the multiple targets; generating a second function by cancelling interference caused by the first target from the first function; and estimating a velocity and an azimuth that maximize a result of the second function as a velocity and an azimuth of a second target among the multiple targets.

A method for calibrating a radar system includes generating an RF oscillator signal and distributing the RF oscillator signal to a plurality of phase shifters each providing a respective phase-shifted RF oscillator signal; receiving the phase-shifted RF oscillator signals by corresponding radar chips and radiating the phase-shifted RF oscillator signal via a first RF output channel of a first one of the radar chips; receiving a back-scattered signal by at least one RF input channel of each radar chip and generating a plurality of base-band signals by down-converting the received signals into a base band using the phase-shifted RF oscillator signals received by the corresponding radar chips; determining a phase for each base-band signal; and adjusting the phase shifts caused by the phase shifters such that the phases of the base-band signals match a predefined phase-over-antenna-position characteristic.

A multiple input multiple output (MIMO) radar system for detecting a moving object is based on an explicit signal model. The explicit signal model accounts for waveform separation residuals by relating measurements of the virtual array to an auto-term including a Kronecker product of object-receiver signatures and transmitter-object signatures; and a cross-term including a Kronecker product of object-receiver signatures and transmitter-object residual signatures. The radar system uses a spatial MIMO object detector that is based on the explicit signal model to detect the moving object.

In an embodiment, a method includes: receiving reflected radar signals with a millimeter-wave radar; performing a range discrete Fourier Transform (DFT) based on the reflected radar signals to generate in-phase (I) and quadrature (Q) signals for each range bin of a plurality of range bins; for each range bin of the plurality of range bins, determining a respective strength value based on changes of respective I and Q signals over time; performing a peak search across the plurality of range bins based on the respective strength values of each of the plurality of range bins to identify a peak range bin; and associating a target to the identified peak range bin.

Trapped or confined individuals may be located and rescued by detecting their movement using reflected, radio frequency signals over a range of multiple antenna polarities.

A method with grid map generation includes: determining position information of a moving object corresponding to a first time step based on a position sensor of the moving object; determining detection information of nearby objects present around the moving object corresponding to the first time step based on a radio detection and ranging (radar) sensor of the moving object; selecting a still object in a moving range of the moving object from among the nearby objects, based on the position information and the detection information; updating a point cloud determined based on the radar sensor in a previous time step of the first time step, based on the position information and on detection information of the still object comprised in the detection information of the nearby objects; and generating a grid map based on an occupancy probability for each grid of the updated point cloud.

Provided is a radar apparatus whose performance is enhanced. The radar apparatus, includes: signal generation circuitry, which, in operation, generates a plurality of chirp signals; and a transmission antenna, which, in operation, transmits the plurality of chirp signals. The signal generation circuitry configures a transmission delay for the plurality of chirp signals for each of a predetermined number of transmission periods, where the predetermined number is greater than or equal to two. The signal generation circuitry changes a center frequency of the plurality of chirp signals for each of the predetermined number of transmission periods.

An electronic device includes: a radar sensor configured to radiate a radar signal and receive a reflected signal of the radiated radar signal by: transmitting at least some chirp signals among a plurality of chirp signals belonging to the same frame through a single antenna among a plurality of antennas of the radar sensor; and transmitting other chirp signals among the plurality of chirp signals belonging to the same frame through at least two antennas among the plurality of antennas; and one or more processors configured to detect a target and determine a direction of arrival (DOA) of the target from radar data determined based on the at least some chirp signals, the other chirp signals, and the reflected signal.

A beat frequency signal processing method includes determining a two-dimensional (2D) time frequency spectrogram of a beat frequency signal based on a sampled sequence of the beat frequency signal, where the 2D time frequency spectrogram indicates a relationship between a frequency and a time of the beat frequency signal; performing matching between the 2D time frequency spectrogram of the beat frequency signal and a plurality of theoretical 2D time frequency spectrograms to determine, as a target 2D time frequency spectrogram, a theoretical 2D time frequency spectrogram whose matching degree is greater than or equal to a preset threshold. The plurality of theoretical 2D time frequency spectrograms are 2D time frequency spectrograms of the beat frequency signal, under combinations of a plurality of flight times and a plurality of Doppler frequency offsets, that are calculated based on a frequency sweep curve of the frequency modulated signal.