25 results about "Coherent processing interval" patented technology

The invention discloses a strong real-time signal processing method based on multi-stream processing, and the method comprises the steps: carrying out the remainder of a preset stream number of received coherent processing interval data through a CPU according to a CPI number, obtaining a stream number, distributing the coherent processing interval data to each stream distributed calculation program corresponding to the stream number, each stream distributed computing program comprises a CUDA stream and a CPU processing thread which are executed in sequence; the GPU and the CPU execute each stream distributed calculation program to overlap the calculation time and the data copying time of the CUDA stream and the CPU processing thread to obtain each trace point condensation data with different completion time; the CPU obtains the corresponding report to be sent according to the trace point condensation data, and orderly sends the report to be sent to the target program based on a report waiting synchronization mechanism, and the application can complete front-end downloading data receiving, detection processing and report sending in strong real time, thereby improving the development efficiency, shortening the product development period, and reducing the project cost.

The invention provides a distributed millimeter wave radar network oriented orthogonal waveform design method, a medium and equipment, and belongs to the field of radar signal processing. The initial frequency of each linear frequency modulation signal is linearly increased in each coherent processing interval, a large bandwidth is synthesized in a slow time domain in a frequency modulation mode, so that a stepping double-frequency-modulation waveform with a variable center frequency is generated, DDM coding of different Doppler frequency band numbers is implemented in each radar unit based on the waveform, and the frequency modulation frequency of each radar unit is increased. FDM coding is implemented among radar units for coordination, MIMO waveform design of simultaneous orthogonal emission of multiple emission antennas is finally completed, and complete separation is realized through a distance Doppler spectrogram. The method is flexibly suitable for different types of distributed millimeter wave radar networks and MIMO structures, effectively overcomes the limitations of low range resolution and small range Doppler ambiguity-free range in the existing method, and greatly improves the MIMO coding effect and multi-target ambiguity-free detection and parameter estimation performance of the distributed millimeter wave radar networks.

A precipitation scanning aperture RADAR system comprises at least one transmitting satellite (TX) and a plurality of receiving satellites (RXs) flying in a multi-static formation. The TX emits fixed frequency, pseudo-random, non-repeating phase modulated RADAR energy. Range and Doppler information is extracted from reflected signals received by the RXs to form coherent 2D along track / vertical images, which are combined into a 3D reflectivity map using a power-based incoherent modeling algorithm, such as a Gaussian mixture model. Embodiments implement a spotlight mode in which, for each RX, a plurality of the coherent 2D images obtained during successive coherent processing intervals (CPIs) are incoherently combined, and the satellites adjust their orientations between each CPI to compensate for satellite movement. Inter-satellite timing synchronization of 10 ns or better is sufficient for forming the 3D reflectivity map. The range and Doppler information can be extracted by concurrently demodulating at a plurality of reference frequencies.

This invention discloses a method for identifying dragged interference based on the transmit-receive spatial frequency spectrum, belonging to the field of radar signal processing technology. The invention includes: constructing an FDA-MIMO radar transmitter array and receiver array; calculating the transmitted signal of the transmitter array elements according to a preset frequency increment; receiving the target and interference echo signals of the receiver array, obtaining the target and interference signal vectors within a CPI; calculating the echo covariance matrix based on the target and interference signal vectors, and estimating its Capon spectrum; accumulating the Capon spectrum of multiple coherent processing intervals, then performing peak search to obtain the trajectory of the target and interference, and segmenting the trajectory; calculating the Euclidean distance between peaks within each trajectory, and calculating its variance to identify dragged interference. This invention utilizes the difference in trajectory characteristics between dragged interference and real targets in the transmit-receive spatial frequency spectrum domain of the FDA-MIMO radar, and distinguishes dragged interference from real targets by the magnitude of the trajectory variance without needing to estimate the target velocity.

The invention discloses a multi-static radar physical target and active false target identification method, and belongs to the field of target identification and interference resistance. The method comprises the following steps: estimating deception parameters of a target in a plurality of coherent processing intervals on the basis of measurement information based on a multi-static radar, so as to combine and form a deception parameter vector; according to the characteristic that physical target deception parameters approximately obey zero mean Gaussian distribution, variance is calculated, and a reference vector is constructed; mapping the deception parameter vector and the reference vector to a matrix manifold or a power spectrum manifold; adopting total Bregman divergence and three types of geometric metrics thereof to define a geometric distance; calculating a geometric distance between the target mapping point and the reference point; and comparing the result with a threshold value to realize the discrimination of the physical target and the false target. According to the method, the separability of physical target and false target distribution is enhanced by utilizing information geometric measurement, and the discrimination performance is remarkably improved; the method can achieve excellent performance under the condition of a small number of samples, adapts to real-time countermeasure requirements, and is high in target recognition robustness and controllable in complexity.

A communication method and an apparatus, which are applied to the technical field of communications. The method comprises: a first communication apparatus transmits first information, wherein the first information comprises information of a coherent processing interval supported by the first communication apparatus and / or information of a cross-coherent processing interval supported by the first communication apparatus. The information of the coherent processing interval comprises the maximum duration of the coherent processing interval and / or the maximum number of time units comprised in the coherent processing interval, the information of the cross-coherent processing interval comprises the maximum duration of the cross-coherent processing interval and / or the number of coherent processing intervals comprised in the cross-coherent processing interval, the cross-coherent processing interval comprises M coherent processing intervals, and M is an integer greater than 1. The embodiments of the present application can acquire the capability of sensing receiver devices for processing sensing signals, thus helping to improve the sensing performance.

The present invention relates to a method and device for imaging a target rotating component based on micro-Doppler phase compensation. The method includes: processing the overall echo pulse signal of the target based on micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component. Calculating the translational phase compensation coefficient of the target rotating component according to the prior information. Within the coherent processing interval, calculating the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the echo pulse in the angular channel where the starting coherent processing moment is located according to the echo pulse signal. Obtaining the echo accumulation result of all scattering points of the target rotating component according to the translational phase compensation coefficient and the rotational phase compensation coefficient, and calculating the imaging result in the angular domain space according to the echo accumulation result. By using this method, an image of the angular domain space distribution of the rotating components of a low-altitude rotor target can be obtained, thereby improving the accuracy of target feature extraction and enhancing the radar's classification and recognition ability for low-altitude targets.

The invention relates to a local mismatched filter design based on a radar communication integrated waveform. The local mismatched filter design comprises the following steps: acquiring M discrete transmitted waveform vectors planned to be transmitted within a coherent processing interval; constructing a weighted summation optimization problem model based on the M transmitted waveform vectors; carrying out iterative solution on the optimization problem model by adopting an alternating direction multiplier method, and outputting M local mismatched filter coefficient vectors; wherein the M local mismatched filter coefficient vectors are respectively matched with the M discrete transmitted waveforms, and are used for carrying out filtering processing on the received echo signal at a receiving end of the radar communication integrated system so as to suppress distance sidelobe modulation and improve the moving target detection performance. The method can be applied to receiving end processing, the RSM effect can be fundamentally suppressed, clutter responses of different pulses can be effectively aligned and cancelled in cancellation processing, and therefore the moving target detection capacity of a system under the strong clutter background is remarkably improved.

The invention discloses a clutter suppression method based on low-rank approximate point iteration, which comprises the steps of processing radar echo data to obtain baseband data containing clutter signals, processing the baseband data containing the clutter signals according to a set coherent processing interval, constructing a distance Doppler two-dimensional matrix and obtaining a sparse expression of the distance Doppler two-dimensional matrix; and finally, carrying out iterative solution according to a low-rank approximate point iterative algorithm, substituting the solved data into a distance Doppler two-dimensional matrix, and carrying out parameter detection and estimation on the distance and the speed of the target. According to the scheme, the sparse characteristic of the target and the low-rank performance dual constraint of clutter are utilized, the moving target detection probability is improved by adopting a low-rank approximate point iteration method, the problem of moving target detection under the influence of clutter in a complex natural environment can be solved while clutter signals are effectively suppressed, the clutter signal suppression effect is effectively improved, and the moving target detection efficiency is improved. And the target discovery probability is greatly improved.

An example method for integrated sensing and communication performed by a configuring device, the method may comprise obtaining a radio frequency (RF) sensing resource pool comprising symbols partitioned by coherent processing intervals (CPIs). The method may also comprise selecting one or more CPIs from the CPIs partitioning the RF sensing resources and selecting a sensing symbol pattern for each CPI of the one or more CPIs, from the respective set of predefined sensing symbol patterns that can be used for the CPI, based on a set of RF sensing property requirements of the first sensing device. The method may further comprise configuring the first sensing device to perform the RF sensing using the selected one or more CPIs and the selected sensing symbol pattern for each CPI of the one or more CPIs.

The present invention discloses a beam tracking method and system based on an orthogonal dual-frequency uniform linear array. The method comprises: initializing base station parameters and kinematic parameters, wherein the kinematic parameters include the velocity vector and position vector of the target, and the base station includes an orthogonal dual-frequency linear antenna array; performing two-dimensional projection on the kinematic parameters to calculate the echo signal reflected by the target received by the base station; performing matrix modeling on the echo signal received by the base station in each coherent processing interval to obtain a multi-dimensional matrix of the echo signal; iteratively solving the multi-dimensional matrix of the echo signal in each coherent processing interval to obtain a target velocity prediction value and a target position prediction value. The present invention avoids co-frequency interference between signals by allocating different carrier frequencies to the two linear subarrays. The projection transformation improves the perception accuracy of the target motion state and enhances the joint estimation capability of the multi-dimensional velocity components of the moving target, thereby improving the overall performance of the system.

A moving target indicator radar system can include a radar transceiver. The system can further include processing circuitry. The processing circuitry can provide a command to move an antenna beam in an azimuth direction. The processing circuitry can further control the radar transceiver to transmit a series of pulses throughout antenna beam motion such that the series of pulses are assembled into Coherent Processing Intervals (CPIs) and such that for a possible target, sequential sets of CPIs are combined covering at least a 3 dB portion an azimuth beam. The processing circuitry can further detect at least one moving target in at least one CPI. Other apparatuses and methods are also described.

The application provides a sea clutter simulation method based on an air-based bistatic radar system, which comprises the following steps: a radar carried on a satellite launch platform irradiates a sea surface to be monitored, and a sea area irradiated by each radar in a coherent processing interval (CPI) is divided into multiple sub-regions; a sea clutter frequency domain algorithm is used to determine a single-beam monopulse sea clutter signal corresponding to each sub-region based on the frequency domain characteristics of each sea surface scattering point in the sub-region; and an echo signal corresponding to a beam in the coherent processing interval (CPI) of each radar is determined according to the single-beam monopulse sea clutter signal corresponding to each sub-region. The sea clutter frequency domain algorithm can convert a relatively complex Fourier transform into frequency shift and linear calculation, thereby reducing the calculation amount of simulation and improving the simulation efficiency.

A radar system includes a radar receiver configured to receive return signals reflected from within a volume of radar coverage. A processor for processing the return signals extracts characteristics from a return signal received in a corresponding coherent processing interval. The extracted characteristics include a set of frequencies and / or a set of times, each frequency and / or time having a respective extracted amplitude of a corresponding set of extracted amplitudes. The processor determines a corresponding amplitude index for each extracted amplitude; and for each extracted amplitude, respectively stores in a memory location addressable via the corresponding amplitude index, a set of return signal related data including information for identifying the corresponding frequency and / or time, and an associated identifier for uniquely identifying, in combination with the amplitude index, that set of return signal related data.

The invention discloses a faint target detection method and device and a medium, and relates to the technical field of radar signal processing and time frequency control. The method comprises the following steps: implementing a time-frequency discipline on a near-end reference through an atomic clock, and establishing a phase-stable reference across a coherent processing interval; echo signals are collected in a segmented mode according to coherent processing intervals, range walk correction and phase compensation are carried out on echoes of all segments according to the motion state of the platform, and coherent accumulation in the segments is achieved; calculating a phase continuity quality factor; based on the phase continuity quality factor, performing adaptive selection between coherent splicing and semi-coherent power superposition to obtain a cross-segment synthesis result; and performing likelihood fusion and constant false alarm detection on the cross-segment synthesis result in a statistical layer, and outputting a target existence judgment and parameter estimation result. According to the invention, a high coherence retention rate can be maintained and a false alarm can be stably controlled in the presence of platform maneuvering and environmental disturbance, so that the first detection probability and the continuous tracking capability of a long-distance low observable target are improved.

The invention provides a sea clutter suppression method and device, and the method comprises the steps: carrying out the constant false alarm detection of single-frame echo data, and obtaining an initial trace point information matrix; judging whether elements in the initial trace point information matrix reach or exceed a preset threshold value; if not, eliminating the single-frame echo data; if yes, dynamically calculating a proportionality coefficient through a proportionality coefficient calculation expression in combination with the sea clutter 3dB spectral width and the single-frame original coherent processing interval; based on the proportionality coefficient, performing short-time accumulation on the single-frame echo data, and performing constant false alarm detection on an accumulation result to generate a short-time plot information matrix; when elements in the short-time plot information matrix reach or exceed a preset threshold value, determining plot attributes corresponding to the elements according to a size relationship between an element proportion between the initial plot information matrix and the short-time plot information matrix and a proportionality coefficient K; and carrying out clutter trace point elimination based on trace point attributes. Therefore, sea clutter suppression is realized.

The present invention discloses a method for identifying radar towing interference, which comprises the following steps: S1. Obtain a radar received signal, sample and accumulate the signals within the first pulse repetition interval in multiple coherent processing intervals of the received signal to form a one-dimensional discrete sequence; S2. Decompose the one-dimensional discrete sequence in step S1 by using the Mallat algorithm of discrete wavelet transform to obtain a sequence composed of high-frequency coefficients of each layer at the J-layer scale; S3. According to the characteristics of the one-dimensional discrete sequence in step S1, circularly shift the sequence composed of high-frequency coefficients of each layer in step S2 to obtain a shifted sequence; S4. Calculate the correlation coefficients between the sequence composed of high-frequency coefficients of each layer in step S3 and the shifted sequence, and construct a multi-dimensional wavelet feature vector r; S5. Use a classifier to classify and identify the feature vector r for range towing interference, velocity towing interference, and range-velocity combined towing interference. The present invention is applicable to the radar tracking mode and greatly improves the recognition accuracy rate.

The invention provides an MIMO radar maneuvering target trajectory tracking method and device, and belongs to the field of array signal processing. The method comprises the steps that echo signals collected by a multiple-input-multiple-output radar in a single coherent processing interval are constructed into a third-order data tensor, the tensor is divided into a plurality of sub-blocks along the time dimension, and a discrete estimation result of a target direction of arrival is obtained; based on the estimation result, fitting kinematic model parameters of the target to obtain initial values of dynamic trajectory parameters of the target; and then dynamic trajectory parameters are solved through structured alternating nonlinear least square iteration, and a direction-of-arrival trajectory of the target in a coherent processing interval is obtained in combination with a kinematic model. According to the method, the motion rule of the target is directly fused into the signal model, a complete track is obtained through one-time calculation of the whole batch of data, high-precision and high-reliability tracking can still be achieved when the target motion is complex and the signal is weak, and the problem that a traditional method fails due to target motion is solved.

The present invention relates to a fractional Fourier transform fusion pulse - to - pulse switching method for low - slow - small target detection, belonging to the field of radar. In the present invention, the echoes with different PRFs are extracted according to the pitch angle pointing, and the echoes with the same pointing are recombined in chronological order into a coherent processing interval, and the echoes with different pointings form multiple CPIs; for a uniformly moving target, the high - Doppler channel uses MTI cascaded with windowed FFT, and the low - channel uses a FIR filter to obtain a range - Doppler map; for a maneuvering target, the fractional Fourier transform is used to obtain the target acceleration, and the quadratic phase term caused by the acceleration is compensated in the echo, and after compensation, MTI cascaded with windowed FFT is used to obtain a range - Doppler map; the obtained range - Doppler map is detected and processed to obtain the angle information of the target. The present invention uses fractional Fourier transform fusion pulse - to - pulse switching to achieve the detection of "low - slow - small" targets, improving the detection probability of "low - slow - small" UAV targets.

The invention relates to a target rotating part imaging method and device based on micro Doppler phase compensation. The method comprises the following steps: processing an integral echo pulse signal of a target based on a micro-Doppler technology to obtain prior information of a target rotating part and a separated echo pulse signal of the target rotating part; and calculating a translation phase compensation coefficient of the target rotating part according to the prior information. And in the coherent processing interval, according to the echo pulse signal, calculating a rotation phase compensation coefficient of the echo pulse of the scattering point of the target rotating part from the angle channel where the coherent processing starting moment is located. And according to the translation phase compensation coefficient and the rotation phase compensation coefficient, obtaining an echo accumulation result of all scattering points of the target rotation component, and according to the echo accumulation result, calculating an imaging result of the angular domain space. By adopting the method, the angular domain spatial distribution image of the low-altitude rotor target rotating part can be obtained, so that the target feature extraction precision is improved, and the classification and recognition capability of a radar on a low-altitude target is improved.

A communication method and device, applied to the technical field of communications, the method comprising: a first communication device sending first information, the first information comprising information of a coherent processing interval supported by the first communication device and / or information of a cross-coherent processing interval supported by the first communication device, the information of the coherent processing interval comprises the maximum duration of the coherent processing interval and / or the maximum number of time units included in the coherent processing interval, and the information of the cross-coherent processing interval comprises the maximum duration of the cross-coherent processing interval and / or the number of coherent processing intervals included in the cross-coherent processing interval; wherein the cross-coherent processing interval comprises M coherent processing intervals, and M is an integer greater than 1. According to the embodiment of the invention, the processing capability of the sensing receiving end equipment on the sensing signal can be obtained, and the sensing performance can be improved.

The invention discloses a beam tracking method and system based on an orthogonal dual-frequency uniform linear array, and the method comprises the steps: initializing base station parameters and kinematics parameters, the kinematics parameters comprise a speed vector and a position vector of a target, and the base station comprises an orthogonal dual-frequency linear antenna array; performing two-dimensional projection on the kinematics parameters to calculate echo signals reflected by a target and received by the base station; performing matrix modeling on the echo signals received by the base station in each coherent processing interval to obtain an echo signal multi-dimensional matrix; and iteratively solving the echo signal multi-dimensional matrix of each coherent processing interval to obtain a target speed predicted value and a target position predicted value. According to the invention, different carrier frequencies are allocated to the two linear sub-arrays, so that same-frequency interference between signals is avoided. Through projection transformation, the perception precision of the target motion state is improved, and the joint estimation capability of the multi-dimensional velocity component of the moving target is enhanced, so that the overall performance of the system is improved.

A moving target indicator radar system can include a radar transceiver. The system can further include processing circuitry. The processing circuitry can provide a command to move an antenna beam in an azimuth direction. The processing circuitry can further control the radar transceiver to transmit a series of pulses throughout antenna beam motion such that the series of pulses are assembled into Coherent Processing Intervals (CPIs) and such that for a possible target, sequential sets of CPIs are combined covering at least a 3 dB portion an azimuth beam. The processing circuitry can further detect at least one moving target in at least one CPI. Other apparatuses and methods are also described.

The application provides a multi-pulse repetition frequency (PRF) based integrated sensing and communications (ISAC) waveform design method, which improves the range ambiguity problem of the ISAC system. First, the full-duplex ISAC node transmits different PRF waveforms in multiple coherent processing intervals (CPIs), and under each PRF, fixed-length sensing signals and variable-length communication symbols are transmitted in turn. Second, the full-duplex ISAC node knows the transmitted sensing waveform, and performs target echo matched filtering. Third, the full-duplex self-interference and noise are reduced through pulse-Doppler processing. Finally, when the target is detected in all CPIs, the target apparent time delay in each CPI is obtained according to the range-Doppler matrix, the real time delay is solved by combining the remainder theorem, and the real distance of the target is estimated. The waveform method designed by the application has the ability to resist range ambiguity, significantly expands the maximum unambiguous range, and improves the detection probability and distance estimation accuracy of long-distance targets.

The present invention belongs to the technical field of target detection methods, and particularly relates to a method for detecting small and weak targets in a strong motion clutter environment, including the following steps: suppressing the signal sidelobes after radar echo pulse compression within the coherent processing interval by using the method of adding a Hamming window in the frequency domain, and then performing constant false alarm rate detection after moving target detection processing; determining whether the targets detected by the CFAR detector are strong motion clutter; accurately estimating the spectral center of the strong motion clutter by using a spectral center compensation method based on a rearranged spectrogram, and then compensating the spectral center of the strong motion clutter to the zero-frequency position; suppressing the strong motion clutter by using the method of an adaptive high- and low-order pulse pair cancellation moving target indication filter; and restoring the spectral position of the data after suppressing the strong motion clutter. The present invention avoids the mutual influence caused by noise and when the spectral center energies of multiple targets are relatively close, and can accurately estimate the spectral center position of the strong motion clutter.