73 results about "Continuous-wave radar" patented technology

A mechanism for generating a modulation signal for use in a radar system. The modulation signal includes a sequence of chirps. Each chirp includes an active period, a transition period and an idle period. During the active period, the frequency of the chirp moves from a start frequency to an end frequency. During the transition period, the frequency of the chirp moves towards the start frequency of the next chirp. The rate of change of the frequency, during the transition period, is different for different chirps of the modulation signal.

A radar device may generate an integrated range-velocity map by combining data from a plurality of range-velocity maps. Each range-velocity map may be associated with a respective radar channel from a plurality of radar channels. The radar device may identify a first peak in the integrated range-velocity map. The first peak may indicate one or more radar targets in the integrated range-velocity map and being identified by a first bin having a first range-velocity bin index. The radar device may determine a first data set by extracting, from each range-velocity map, data that is included in a respective bin associated with the first range-velocity bin index. The radar device may process the first data set to determine a first set of phase imbalances associated with the plurality of radar channels.

The invention discloses a fractional frequency division frequency synthesizer with output signal phase synchronization and frequency modulation continuous wave functions, and the basic structure is a charge pump phase-locked loop. Comprising a phase frequency detector, a first charge pump, a second charge pump, a low-pass filter, a voltage-controlled oscillator, a first buffer, a second buffer, a two-frequency divider chain, an IQ undersampling circuit, a local oscillator generator, a programmable multimode frequency divider, a Delta-Sigma modulator (DSM), a first selector, a second selector, a third selector, a tracking phase accumulator, a numerical control oscillator, an accumulation phase difference register and an atan2 logic circuit. The device comprises a main phase control circuit, a phase adjusting circuit, an enabling control circuit, a waveform generator and a serial peripheral interface. The decimal frequency-division frequency synthesizer can be applied to a general-inductance integrated system, ensures that output signals provided by a plurality of decimal frequency-division frequency synthesizers are consistent in phase in a multi-channel radio frequency transceiving system adopting a multi-chip splicing mode, and can also be applied to the general-inductance integrated system as a sensing signal source; and the speed and the distance of an object can be quickly sensed by the high linearity and the quick chirp capability of an output signal. The decimal frequency division frequency synthesizer is applied to a linear frequency modulation continuous wave radar system, initial phase synchronization can be carried out firstly, then frequency continuous modulation is carried out, and measurement errors can be eliminated. In view of functional similarity of partial modules of the synchronous loop and the FMCW loop, such as a phase frequency detector, a charge pump, a voltage-controlled oscillator and the like, the modules can be shared, so that the power consumption and area cost of the system are remarkably reduced.

The invention relates to the technical field of laser radars, in particular to a non-aliasing frequency-modulated continuous wave radar detection system and method, and the system comprises a light source, a beam splitter, a circulator, a 90-degree mixer, a signal conversion module and a signal processing unit. The signal processing unit is configured to construct a composite vector signal S based on the first electric signal I and the second electric signal Q, S = I + jQ, j is an imaginary part operator, obtain a double-sideband spectrum based on the composite vector signal S, determine the frequency of a signal peak in an upper frequency sweeping period and the frequency of a signal peak in a lower frequency sweeping period in the double-sideband spectrum, and determine the frequency of the signal peak in the upper frequency sweeping period and the frequency of the signal peak in the lower frequency sweeping period; and obtaining the distance and speed of the target to be measured based on the frequency of the signal peak in the upper frequency sweeping period and the frequency of the signal peak in the lower frequency sweeping period. According to the invention, the problem of signal aliasing during detection of the to-be-detected target can be solved at least.

The invention provides an auxiliary identification method and device for single-phase depression and double-phase depression. The method comprises the steps that a millimeter wave frequency modulation continuous wave radar is used for collecting thoracic cavity micro-motion signals of a subject in a non-contact mode; filtering and phase demodulation are carried out on the thoracic cavity micro-motion signal, respiration components and heartbeat components are separated, and an RR interval sequence is extracted from the heartbeat components; calculating heart rate variability characteristics according to the RR interval sequence, wherein the heart rate variability characteristics comprise a time domain index, a frequency domain index and a nonlinear index; and inputting the heart rate variability characteristics into a pre-trained auxiliary identification model to obtain a depression identification result of the subject. According to the invention, a non-contact measurement method is adopted, so that stress reaction possibly caused by a contact sensor is avoided, and interference to physiological signals is reduced; and meanwhile, complex features in the data can be automatically extracted by using a deep learning model, so that the identification accuracy and generalization ability are improved.

A phased array frequency-modulated continuous-wave (FMCW) radar system configured to transmit, using a plurality of antennas, a plurality of chirps, wherein each chirp within the plurality of chirps includes at least one temporal characteristic, and wherein the at least one temporal characteristic is pseudo-random for a portion of the plurality of chirps, to receive, using the plurality of antennas, a plurality of chirp reflections off one or more targets, to create, using a mixer, an intermediate frequency based on the plurality of chirps and the plurality of chirp reflections, and to determine, based on the intermediate frequency and the at least one temporal characteristic, a target attribute associated with the one or more targets.

The invention discloses a terahertz frequency modulation continuous wave radar signal processing system and method based on an FPGA. The system comprises an A / D acquisition control module, a digital down-conversion module, a fast two-dimensional Fourier transform module, a non-coherent accumulation module and a constant false alarm detection module. The method comprises the following steps that: the A / D acquisition control module samples an analog echo signal; the digital down-conversion module performs digital down-conversion processing on the sampling signal to obtain baseband echo I and Q data; the fast two-dimensional Fourier transform module is used for carrying out FFT (Fast Fourier Transform) on baseband echo I and Q data to obtain a range profile of a target, and the non-coherent accumulation module is used for carrying out amplitude accumulation and averaging on a plurality of target range profiles in different periods in the same wave beam; and the constant false alarm detection module compares and judges the signal amplitude of the detection unit with a set threshold to obtain a false alarm detection result. The method has the advantages of being high in real-time performance, high in reliability, simple in design, high in adaptive capacity and wide in application range.

According to the wind turbine generator blade icing dynamic early warning system provided by the invention, through omnibearing monitoring of the frequency modulation continuous wave radar group, the orthogonal weaving piezoelectric fiber array and the infrared temperature measurement unit, airspace water drop distribution, blade vibration characteristics and multi-dimensional dynamic changes of a surface temperature field are accurately captured; by combining improved Kalman filtering, wavelet transformation and a dynamic weight distribution algorithm of an intelligent decision module, traditional single threshold judgment is upgraded to comprehensive threat index deduction based on digital twinborn bodies, and the temporal-spatial resolution and reliability of icing threat assessment are remarkably improved; the execution control module achieves heating network partition accurate regulation and control and unit operation state collaborative optimization according to the generated anti-icing strategy, energy waste of traditional global heating is avoided, material damage caused by local overheating or underheating is effectively restrained, finally, anti-icing energy consumption is reduced under the complex meteorological condition, and the anti-icing efficiency is improved. And meanwhile, the power generation efficiency loss of the unit under the icing working condition is greatly reduced.

Embodiments are disclosed for a range-gated imager. In some embodiments, a method comprises: transmitting, with a single-tone continuous wave (STCW) radar, a signal; receiving, with the STCW radar, a return signal from a projectile impinged by the radar signal; counting, with a measuring apparatus, a specified number of periods of non-ambiguity range based on the return signal, performing a flashing operation; and gating or triggering, by the measuring apparatus, an imager to capture an image of the projectile in response to the count reaching the specified number of periods.

The present application relates to the technical field of laser radar, and especially relates to a non-aliasing frequency modulation continuous wave radar detection system and method, the non-aliasing frequency modulation continuous wave radar detection system comprising: a light source, a beam splitter, a circulator, a 90-degree frequency mixer, a signal conversion module and a signal processing unit, the signal processing unit being configured to: construct a complex vector signal S based on a first electrical signal I and a second electrical signal Q, S=I+jQ, wherein j is an imaginary operator, and obtain a double sideband spectrum based on the complex vector signal S, determine the frequency of a signal peak in an up-sweeping frequency period and the frequency of a signal peak in a down-sweeping frequency period in the double sideband spectrum, and obtain the distance and speed of a target to be detected based on the frequency of the signal peak in the up-sweeping frequency period and the frequency of the signal peak in the down-sweeping frequency period.The present application is at least beneficial to solve the signal aliasing problem when detecting the target to be detected.

Embodiments are disclosed for a range-gated imager. In some embodiments, a method comprises: transmitting, with a single-tone continuous wave (STCW) radar, a signal; receiving, with the STCW radar, a return signal from a projectile impinged by the radar signal; counting, with a measuring apparatus, a specified number of periods of non-ambiguity range based on the return signal, performing a flashing operation; and gating or triggering, by the measuring apparatus, an imager to capture an image of the projectile in response to the count reaching the specified number of periods.

This disclosure provides a radar module, i.e., a radar system, comprising a PCB substrate, at least two antenna elements, and a radar chip. The difference in the feed path from the radar chip to two adjacent antenna elements is related to the offset angle of the radar module's main radiation direction. The technical solution provided in this disclosure adjusts the deflection of the radar module's main radiation direction through feed path layout design, and, in conjunction with logic algorithms, enables fixed-frequency continuous wave radar to detect and identify moving objects. The technical solution provided in this disclosure is designed based on a shared antenna array for both transmit and receive channels, meeting the requirements for lightweight and integrated design, effectively reducing the size of the radar module, and has widespread applicability.

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.

A method utilizing a radar apparatus and a radar apparatus. The invention relates to a method for determining a distance between a radar device and an object by means of a frequency-modulated continuous wave radar using a radar device. The aim of the invention is to reduce the energy demand for determining the distance without affecting the accuracy. The task is solved by a method comprising the following steps: carrying out the sub-steps in a first step: generating and emitting a frequency-modulated transmission signal; receiving a reflected signal at the object caused by the transmitted signal; and mixing the transmitted signal and the reflected signal with each other to form a mixed signal. In a second step, a sub-step is performed: determining a coarse spectrum of the mixed signal in a coarse frequency range, a spectrum maximum in the coarse spectrum, and a coarse spectrum maximum frequency of the spectrum maximum in the coarse frequency range.

A frequency modulated continuous wave radar sensor according to an embodiment of the present invention may comprise: a signal generator for generating frequency modulated (FM) signals that change frequency over time; a transmission antenna for transmitting the FM signals generated by the signal generator; a reception antenna for receiving reflected signals of the FM signals reflected by an object; a frequency mixer which outputs the difference between the FM signals and the reflected signals; and a filter which extracts a mid-frequency component from the output of the frequency mixer.

The invention discloses a multi-dimensional sensing method and system based on low-complexity variational Bayes, and belongs to the technical field of radar signal processing, and the method comprises the steps: employing a frequency modulation continuous wave radar to collect a discrete beat signal containing the distance and radial speed information of a moving target; modeling unknown variables in the discrete beat signal by adopting a low-complexity variational Bayesian algorithm, calculating joint probability density distribution of the unknown variables, and entering iterative updating; the joint probability density distribution related parameters of the unknown variables are updated in sequence, so that the grid point positions corresponding to the distance domain and the Doppler domain are updated; and judging whether the iterative updating is completed or not, and estimating the distance and radial speed information of the moving target according to the updated grid point positions corresponding to the distance domain and the Doppler domain. According to the invention, the problem of performance loss caused by neglecting joint information among target parameters is solved, and a high-precision, all-weather and high-robustness active sensing solution is provided for an intelligent security scene.

A method and device for determining a relative velocity of a radar target. An FMCW radar measurement is carried out in which a ramp-shaped frequency-modulated transmit signal is sent whose modulation pattern includes a first sequence of ramps succeeding one another offset by a time interval and at least one further sequence of ramps succeeding one another offset by the same time interval, the sequences being temporally interleaved. Received signals are mixed down to baseband signals. From the baseband signals, a two-dimensional spectrum is calculated separately for each of the sequences by two-dimensional Fourier transformation, transformation taking place ramp for ramp in the first dimension and transformation taking place via a ramp index in the second dimension. Based on the positions of a peak in at least two of the two-dimensional spectra of the baseband signals, a value is determined for the relative velocity of a radar target.

Systems and methods relate to in-vehicle sensing and classification via frequency modulated continuous wave (FMCW) radar. Radar reflection signals are received based on the radar transmission signals, and include a plurality of chirps across a plurality of frames. Range-FFT data is generated by performing a fast Fourier transform (FFT) on each chirp of a particular frame. Doppler-FFT data is generated by performing the FFT on the range-FFT data. Point cloud data of a radar subject is generated using the Doppler-FFT data. Doppler features, including a velocity of the radar subject, are extracted from the Doppler-FFT data. Classification data is generated to indicate a sensing state inside a vehicle based on the point cloud data and the Doppler features. The classification data includes class data that classifies the radar subject. A system response is generated to provide an action concerning the sensing state inside the vehicle based on the classification data.

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 a method for inverting atmospheric precipitation particle spectra, belonging to the field of inversion technology. It addresses the limitations of existing technologies in accurately obtaining inversion parameters for ground and atmospheric microphysical parameters, thus hindering understanding of the formation, development, and variation mechanisms of atmospheric cloud precipitation and consequently preventing accurate prediction and interpretation of atmospheric processes and meteorological disasters. The method includes: acquiring the observed power spectrum using C-band frequency-modulated continuous wave radar and employing denoising methods to remove noise levels; constructing the atmospheric power spectrum based on horizontal wind data acquired from wind profiler radar; constructing the raindrop spectrum using ground raindrop data acquired from a ground raindrop spectrometer and a standardized gamma distribution; and performing ground and atmospheric microphysical parameter inversion based on the above results. This invention is used for inverting and obtaining ground and atmospheric microphysical parameters.

A system or method for using a Frequency-Modulated Continuous Wave (FMCW) radar system installed on a harvester for determining yield data, the system or method comprising locating the FMCW radar system on the exterior of a clean grain elevator housing in a fixed location such that a signal may be transmitted into the housing. The signal may be guided by a waveguide and reflected off a surface of a load or the one or more components where the distance to the load or the one or more components is related to one or more properties of the load. The FMCW radar system is configured to use the reflected signal to determine the one or more properties of the load.

In accordance with an embodiment, a frequency modulated continuous wave (FMCW) radar device includes a power amplifier configured to amplify a transmit signal comprising a sequence of frequency-modulated pulses; and control circuitry configured to control the power amplifier to vary an amplitude of the transmit signal, and configured to control the power amplifier to cause the sequence of frequency-modulated pulses to exhibit at least one of the following characteristics: each frequency-modulated pulse of the sequence of frequency-modulated pulses exhibits a non-rectangular amplitude profile, or respective maximum amplitudes of the frequency-modulated pulses vary over the sequence of frequency-modulated pulses.

The invention discloses a vital sign signal enhancement method and system based on a frequency modulated continuous wave radar, and the method comprises the steps: obtaining a radar echo signal, and recombining a fast time sampling point into a subarray in a slow time direction; screening the sub-arrays according to a signal quality evaluation mechanism, and rejecting low-quality sub-arrays to form sparse sub-arrays; digital beam forming of the distance dimension is executed on the sparse subarray, and asymmetric beam pattern constraint is introduced; and extracting vital sign phase information from the slow time signal output by the beam forming. According to the method, the signal-to-noise ratio of the vital sign signal can be improved, the signal detectability is enhanced, and the detection accuracy and robustness are guaranteed.

In described examples, a frequency modulated continuous wave (FMCW) radar system includes an FMCW signal generator, a number N transmitters, N phase shifters, multiple receivers, and a processor. The FMCW signal generator is configured to generate FMCW chirps. Different ones of the phase shifters have different respective base phase shifts selected in response to N. The transmitter is configured to transmit the phase shifted FMCW chirps. The receivers are configured to receive an FMCW chirp reflected by an object in range of the FMCW radar system. The processor is configured to determine a location of the object in range in response to the received FMCW chirp.

The application discloses a dual-frequency microcavity optical frequency comb radar single-detector parallel detection processing method, and belongs to the field of optical precision measurement. The parallel detection processing system comprises two signal microcavity optical frequency combs and a local oscillator microcavity optical frequency comb with a small frequency difference, a signal generator, a circulator, a diffractive optical element, a beam combiner, a balanced detector and a multi-channel data parallel data acquisition and processing module. The signal generator is used for modulating the microcavity optical comb to generate the signal microcavity optical frequency comb and the local oscillator microcavity optical frequency comb with the frequency difference. The coaxial transceiving and comb tooth space separation are realized through the circulator and the diffractive optical element. The single-pixel balanced detector and the acquisition and processing module are used to realize the multi-channel signal parallel acquisition and processing of different comb teeth, and the distance, angle and speed information of a target object are calculated. The application combines the frequency asynchronous sampling of the dual microcavity optical combs and the coherent parallel detection of the single-pixel balanced detector, can simplify the hardware of the frequency modulation continuous wave radar, and saves the number and cost of the detectors.

A frequency modulated continuous wave (FMCW) radar system includes an antenna array having C antennas, where (C = A + B - 1); a first integrated circuit (IC) device including A first sensor inputs; and a second IC device including B second sensor inputs. The first sensor inputs are coupled to a first A of the antennas and the second sensor inputs are coupled to a second B of the antennas, such that a common input of the first sensor inputs and a common input of the second sensor inputs are both coupled to a common antenna. Each IC device receives a reflected signal on each sensor input and mixes the reflected signal to an associated baseband signal based on a local oscillator (LO) signal. Each LO signal has a different phase shift. The LO signals are based on a common LO signal.

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.

The invention relates to the technical field of industrial process measurement and automatic instruments, in particular to a frequency-modulated continuous wave radar storage tank liquid level measurement method which comprises the following steps: acquiring an orthogonal baseband signal and generating a complex distance spectrum based on an uphill linear frequency-modulated signal, a downhill linear frequency-modulated signal and complementary phase coding; extracting reference echoes to calibrate the complex distance spectrum and determine a coding phase alignment angle, and subtracting the fixed structure echoes by using the fixed structure echo dictionary to obtain a fixed structure echo stripping complex distance spectrum and generate residual energy; complementary phase coding coherent combination is carried out based on the coding phase alignment angle, and candidate distance observation and candidate feature vectors are generated according to time delay consistency; and outputting liquid level estimation and confidence coefficient by adopting dynamic programming, performing change point detection on residual energy to generate a dictionary freezing mark and a dictionary rollback mark, generating an active disambiguation control instruction by combining the confidence coefficient, and updating emission scheduling parameters. The false peak and jump are effectively reduced, and the measurement stability and the adaptive anti-interference capability are improved.

This invention discloses a method and system for multi-node mutual positioning in complex environments. Each node can be set as a master node or a slave node. Nodes achieve mutual positioning by transmitting and receiving triangular frequency-modulated continuous wave (FM) signals. When a node operates in master node mode, it synchronizes with the working signals of other slave nodes through coarse and fine synchronization steps. Then, it calculates the distance information of the slave nodes using round-trip time of flight (RTF) and Doppler frequency shift calculations, and estimates the angle information of the slave nodes using the DOA method to complete the positioning of the slave nodes. When a node operates in slave node mode, it waits for the synchronization signal sent by the master node, synchronizes with the master node's signal through coarse and fine synchronization steps, and then sends the synchronized signal back to the master node so that the master node can locate the slave node's position. This invention achieves high-precision mutual positioning between multiple nodes by implementing the working principle of FM continuous wave radar between nodes.