10 results about "Continuous-wave radar" patented technology

A method and apparatus for super-resolution localization of multiple targets using frequency-modulated continuous wave radar includes: determining the number K of targets based on the number of eigenvalues ​​satisfying a condition in the covariance matrix of the acquired radar array signal; finding the frequency values ​​corresponding to the K largest spectral peaks based on the acquired number of targets K, using these frequency values ​​as coarsely estimated intermediate frequency (IF) values, and determining the final IF value using the coarsely estimated IF values; calculating the distance of the corresponding target relative to the center O of the antenna array based on the final IF value; obtaining the noise subspace of the array signal and the steering vector related to the target distance and angle based on the eigenvalues ​​of the covariance matrix of the array signal, constructing a MUSIC spectral function, and determining the estimated value of the target echo signal direction; and then determining the position of the corresponding target. This invention has higher range and angle resolution and lower algorithm complexity, enabling super-resolution localization of multiple targets.

The application provides a ranging system and a ranging method. The ranging system comprises: a frequency-modulated continuous wave radar arranged on a trolley, used for transmitting a detection signal when the trolley is in a running process, and receiving at least a return signal emitted from an active radar tag; and at least one active radar tag arranged at a target position, used for receiving the detection signal, modulating the detection signal, generating and transmitting a response signal with a preset frequency offset; wherein the target position is arranged along the running direction of the trolley; wherein the frequency-modulated continuous wave radar is used for determining effective return signals by detecting the frequency modulation characteristics of the response signal, and determining distance information and / or speed information between the target position and the trolley according to beat signals between the return signals and the detection signals. By using the above technical scheme, the target recognition accuracy can be improved, and the implementation cost can be reduced.

This invention discloses an adaptive cancellation circuit for a frequency-modulated continuous wave radar, comprising the following components: a power divider, which splits the radar signal into two output signals, namely a first transmitted signal and a second signal LO; and a mixer, which receives the two output signals from the power divider, one of which serves as the local oscillator and the other as the receiver; the self-coupling signal delay at the RF input port of the mixer is the same as the delay of the second signal LO. This invention increases the LO trace delay, making the LO trace path delay equal to the antenna self-coupling path delay, thereby bringing the self-coupling intermediate frequency (IF) signal output close to zero frequency. This allows the self-coupling IF signal to be easily filtered out, significantly reducing the signal-to-noise ratio degradation caused by the impulse response.

Transmit antennas and receive antennas are arranged such that multiple virtual antennas have the same location in a time division multiplexed (TDM) frequency modulated continuous wave (FMCW) radar device. At least three special chirps are located in consecutive time slots, respectively, and have different periods, at least one of the at least three special chirps being included in each chirp cycle in a waveform signal transmitted by the multiple virtual antennas having the same location. A Doppler frequency can be uniquely determined from phase difference values between the at least three special chirps in consecutive time slots measured in FMCW radar signals received at the multiple virtual antennas, respectively.

A frequency-modulated continuous wave radar vibration displacement estimation method and system based on dynamic demodulation, medium and equipment, in the method, a fixed frequency-modulated continuous wave radar is used to collect echo signals of a vibrating object surface; the echo signals are amplified, down-converted and low-pass filtered to convert into baseband beat frequency signals, forming a two-dimensional data matrix composed of fast time sampling point number N and slow time sweep frequency number M, zero padding fast Fourier transform is performed on the baseband beat frequency signals of the first sweep cycle, and the phase estimation value of the first sweep cycle is calculated based on the maximum likelihood phase estimator; for the baseband beat frequency signals of the mth sweep cycle, dynamic demodulation is performed and the phase is updated to obtain an updated phase sequence; the updated phase sequence is phase unwrapped; and the phase is converted into a target line-of-sight direction vibration displacement sequence.

The present disclosure is related to a frequency modulated continuous wave (FMCW) radar system including: a transmitter circuit configured to transmit FMCW chirps at a chirp frequency, wherein the transmitter circuit is operable in either: an acquisition phase, during which the transmitter circuit is configured to change the frequency of an output signal from a first frequency to a second frequency; or a reset phase, during which the transmitter circuit is configured to change the frequency of the output signal from the second frequency to the first frequency; where an FMCW chirp is defined by the output signal over the course of one acquisition phase and one reset phase; a receiver circuit, the receiver circuit comprising an analogue to digital converter, ADC; and a controller configured to: enable the ADC during each acquisition phase of the transmitter circuit, and disable the ADC during a reset phase of the transmitter circuit.

The application discloses an accumulator piston displacement detection method, system, device and medium, and relates to the technical field of displacement detection. The method comprises the following steps: detecting a target accumulator piston by using a linear frequency modulation continuous wave radar to obtain a to-be-detected difference frequency signal; generating a to-be-detected frequency spectrum diagram according to the to-be-detected difference frequency signal; determining a frequency value corresponding to a maximum amplitude spectrum line and frequency values corresponding to left and right adjacent spectrum lines of the maximum amplitude spectrum line from the to-be-detected frequency spectrum diagram to obtain a group of to-be-detected frequency values; inputting the to-be-detected frequency values into an accumulator piston distance detection model for detection to obtain a predicted distance between the target accumulator piston and the linear frequency modulation continuous wave radar; and the accumulator piston distance detection model is obtained based on long short-term memory network training. The accumulator piston displacement detection method provided by the application comprehensively considers various errors and has the advantages of high efficiency, accuracy and intelligence.

The application discloses a frequency-modulated continuous wave radar system based on magnetic suspension phase compensation and a method thereof, which comprises a magnetic suspension radar system and a phase compensation system. The magnetic suspension radar system comprises a stator assembly and a contactless relatively arranged rotor assembly, the stator assembly is provided with an electromagnetic coil array and a Hall displacement sensor array, and the rotor assembly is integrated with an antenna. The phase compensation system comprises a control module and a direct digital frequency synthesizer. The control module drives the electromagnetic coil array by executing a PID control algorithm, so that the rotor assembly is kept in suspension; an embedded displacement detection unit and a compensation calculation engine acquire a rotor displacement change amount in real time and calculate a phase compensation amount; and the direct digital frequency synthesizer generates a phase pre-corrected linear frequency modulation signal according to the compensation amount and outputs the signal to the antenna for emission. The system isolates mechanical vibration from a physical layer, effectively suppresses phase distortion caused by vibration through real-time phase compensation, and improves the measurement precision and stability of the radar in a dynamic environment.

A frequency-modulated continuous-wave (FMCW) radar system including: a transmitter circuit for transmitting FMCW chirps at a chirp frequency; a receiver circuit with first and second receiver-output-terminals, the receiver circuit comprising: a filter circuit with first and second filter-output-terminals; an ADC comprising a processing-block with first and second processing-block-input-terminals and first and second processing-block-output-terminals; and a switching circuit for selectively putting the receiver circuit into one of a first configuration or second configuration at a switching frequency based on the chirp frequency.

The application provides a weak radar cross section unmanned aerial vehicle radar target detection method and system based on frequency modulation continuous wave radar, belongs to the field of radar signal processing and intelligent sensing, and aims to solve the detection problem of low-altitude weak reflection targets caused by weak echo energy, serious multipath effect and clutter interference. The method synchronously acquires and spatiotemporally calibrates the real-time dynamic differential positioning information of the unmanned aerial vehicle and the radar, automatically generates high-precision labels for supervised learning, and reduces the artificial labeling cost and error. After two-dimensional fast Fourier transform is performed on the radar echo, an adaptive non-uniform compression strategy is adopted to aggregate key timing features to reduce data redundancy. Further, a spatiotemporal feature decoupling enhancement module is used to suppress multipath ambiguity and improve feature separability. Finally, a target detection network based on an encoder-decoder noise reduction reconstruction is constructed to denoise and finely reconstruct the features, so that the weak reflection unmanned aerial vehicle target can be accurately and robustly detected and positioned in a complex environment.