714 results about "Pulse compression" patented technology

The invention relates to the technical field of radar signal processing, in particular to a radar target analytical calculation method based on multi-dimensional data fusion and a radar device. Comprising the following steps: deploying a multi-band radar sensor array comprising an X band, a C band and a Ku band in a radar monitoring area; performing pulse compression and Doppler processing on the time domain echo signal, and extracting a time domain feature; spectral analysis is carried out on the frequency domain signals, and frequency domain features are extracted; performing angle estimation on the spatial signals, and extracting spatial features; a dynamic weight distribution model is constructed, a fusion weight is calculated through an adaptive algorithm based on three-dimensional quality indexes of a real-time signal-to-noise ratio (SNR), feature stability (SI) and data integrity (CI), and a joint representation vector containing time domain, frequency domain and space multi-dimensional information is generated. According to the invention, by deploying the multi-band radar sensor array, the recognition capability of the subtle feature difference of the target is improved.

The invention provides a civil air defense engineering concealed conduit leakage positioning method based on acoustic characteristics, and belongs to the technical field of civil air defense engineering. An acoustic signal acquisition network is constructed by deploying a high-sensitivity hydrophone array, and signals are preprocessed by using a time division multiple access technology and a pulse compression technology; and carrying out time-frequency analysis by applying wavelet transform to extract acoustic features. A time reversal mirror technology is introduced to identify direct propagation and multipath reflection signals, a fluid acoustic coupling propagation equation is constructed to analyze a leakage sound source mechanism, and pipe network topological information and a sound wave speed correction function are combined to compensate a measurement error. Wherein the deep learning pipe network acoustic propagation multi-modal model is fused with a pipeline structure encoder, an acoustic feature extractor and a position prediction decoder, and high-precision leakage positioning and degree evaluation in a complex environment are realized through a three-stage pre-training strategy; the technical problem that it is difficult to accurately locate the position of a leakage point in the complex pipe network environment of civil air defense engineering is solved.

The invention discloses a composite board ultrasonic defect detection method which comprises the following steps: S1, fixing a carbon fiber circumferential winding composite pressure container on a bracket, and establishing a coordinate system with the axis of the container as a z axis; s2, a 40 MHz dry coupling phased array ultrasonic probe is attached to the scanning starting point, and the contact angle of the probe is recorded; s3, moving the probe along the spiral track of the outer surface of the container at the speed of 20mm / s, and collecting A-scanning echo signals of all array elements; s4, performing pulse compression and time domain deconvolution processing on the acquired signal to obtain a time domain echo sequence; s5, delay time is calculated according to the shell curvature, the array element signals are compensated, and focusing B-scanning data are generated; s6, splicing the B-scanning data at the step length of 0.5 mm * 0.5 mm, and reconstructing C-scanning data corresponding to the space coordinates; and S7, inputting the C-scanning data into the trained Transform network, and outputting defect types, sizes and three-dimensional coordinates. The method realizes high-frequency ultrasonic composite board defect accurate detection, remarkably improves the microcrack recognition rate, and is widely applied to safety evaluation scenes of high-pressure hydrogen storage tanks and pressure vessels.

The invention discloses a multi-channel radar foresight imaging method based on sparse and weighted low rank, and solves the problem that the foresight super-resolution imaging effect is limited in a complex imaging scene in the prior art. The method comprises the following steps: establishing an echo signal model in a multi-channel radar single-transmitting single-receiving mode, and obtaining an echo signal corresponding to each target; carrying out pulse compression and correction processing, representing a two-dimensional echo matrix, and carrying out weighting processing on a target signal matrix in the two-dimensional echo matrix to obtain a weighted target signal matrix with a low-rank characteristic; obtaining a foresight imaging model according to the sparsity of the target in the echo signal model and the low-rank characteristic of the weighted target signal matrix; solving the foresight imaging model based on ALM under an ADMM framework to obtain a reconstructed foresight high-resolution image; according to the method, the high-quality and high-resolution reconstructed foresight high-resolution image is obtained through sparse and weighted low-rank dual constraints.

The invention discloses a multi-sideband chirp modulation DAS system and a working method thereof, and relates to the technical field of distributed sound wave sensing. The DAS system comprises a narrow linewidth laser, an optical fiber coupler, a phase modulator, an electro-optical modulator, an erbium-doped optical fiber amplifier, an optical fiber circulator, a dense wavelength division multiplexer, a photoelectric balance detector, a data acquisition card, an arbitrary waveform generator, a direct current source and the like. The phase modulator is used for modulating constant-amplitude multi-frequency continuous light, the frequency number of light waves is related to the harmonic number of a microwave modulation signal, the frequency interval is determined by the fundamental frequency of the microwave modulation signal, the continuous light frequency can be flexibly modulated by adjusting the microwave modulation signal, and the modulation bandwidth is large; detected beat frequency signals are compressed into single-frequency signals through pulses, phase information of the single-frequency signals is demodulated, vibration signals along the sensing optical fiber can be detected, the spatial resolution of the system depends on the chirp frequency sweeping range, and the spatial resolution is high.

The invention relates to an underwater acoustic image reconstruction method based on angle error compensation, which comprises the following steps of: (1) calculating space coordinate information and a two-way slant range course of a transmitting array element and a receiving array element for each subsystem consisting of the receiving array element and the transmitting array element; (2) calculating a two-way slant range course after phase center approximation; (3) calculating a system function of a distance-Doppler domain; (4) calculating a Doppler phase error; (5) dividing the data into # imgabs0 data blocks which are not overlapped with one another, and compensating micro-range migration errors caused by range errors; (6) obtaining a signal after distance delay error compensation; (7) performing differential range migration correction processing, range pulse compression, secondary range pulse compression and consistent range migration correction processing; (8) carrying out azimuth focusing processing, residual phase error compensation operation and azimuth walking correction processing; and (9) performing coherent fusion processing and inverse Fourier transform to obtain a final high-resolution image. According to the method, the image can be quickly reconstructed, and the real-time processing requirement can be met.

The invention discloses a spaceborne synthetic aperture radar scattering wave mutual interference suppression method and system based on matched filtering, a storage medium and electronic equipment, and the method comprises the following steps: estimating related parameters of mutual interference according to the prior information of an orbit and a time-frequency relation, and carrying out the range pulse compression of an interference signal in echo data; detecting whether the range pulse contains interference or not by adopting a maximum characteristic value sequence detection method; calculating a relative signal to interference ratio containing interference pulses; reconstructing and extracting interference signals under the conditions of high signal to interference plus noise ratio and low signal to interference plus noise ratio respectively by using a feature subspace projection method and a robust principal component analysis method; and filtering the echo data, and carrying out mutual interference inverse distance compression processing on the data so as to recover normal echoes without interference. According to the invention, the compression gain of mutual interference can be effectively utilized, mutual interference signals in synthetic aperture radar echoes can be extracted more effectively, and high-precision interference suppression is completed while useful signals are better protected.

The invention discloses an imaging method, system and device for correcting range migration based on frequency domain phase multiplication, and the method comprises the following steps: carrying out the range pulse compression of echo data of each receiving array element in a range frequency domain; performing data preprocessing according to a phase center approximation method to obtain equivalent transmit-receive combined synthetic aperture sonar data; deriving a secondary distance compression item at the reference distance in the two-dimensional frequency domain, and performing secondary distance compression processing; deriving a space-variant migration phase term of range migration correction corresponding to each target with different distances; carrying out filtering processing on the two-dimensional frequency domain sonar data; a filtered result is converted to a range-direction time domain and an azimuth-direction Doppler domain, data of targets at corresponding distances are extracted, and the data extracted each time are combined in sequence; and for the data after range migration correction, azimuth pulse compression is carried out in a range time domain and an azimuth Doppler domain, and the data is converted to a two-dimensional time domain to obtain a sonar image.

The invention discloses a single-bit composite interference generation method for a radar, and the method comprises the steps: generating a digital orthogonal linear frequency modulation signal based on a direct digital frequency synthesis technology module, and correspondingly generating a linear frequency modulation signal, thereby generating a radar signal, and carrying out the signal transmission process of the radar; obtaining first user setting, selecting target threshold data, and carrying out single-bit sampling quantization on the radar signal to obtain a plurality of single-bit data so as to carry out a single-bit interception process; obtaining a second user setting, selecting a target interference modulation mode, and performing interference modulation on all single-bit data to obtain a composite interference modulation signal; and outputting the composite interference modulation signal according to the digital signal output setting and the analog signal output setting so as to carry out an interference forwarding process. According to the method, single-bit interception can be carried out on radar signals, rapid composite interference modulation can be completed, and interference countermeasure on a pulse compression system radar device is completed in combination with verification of a semi-physical device.

The invention provides a vortex electromagnetic wave radar multipath virtual image suppression method and system, and relates to the technical field of radar imaging virtual image suppression, and the method comprises the steps: adjusting the circular ring radiuses corresponding to different modes in a uniform concentric circular ring array according to the prior information of a target pitch angle, and obtaining the radar emission configuration of main lobe alignment; performing time domain sampling on the multi-path vortex radar echo signal in each mode to form a two-dimensional radar echo matrix; analyzing the obtained two-dimensional radar echo matrix and the MISO system echo after phase compensation by using an azimuth dimension point spread function to obtain dual-system imaging features; and performing modal domain FFT and time domain pulse compression processing on the multipath echo features under the MISO and MIMO systems by using fast Fourier transform and pulse compression, and finally outputting a virtual image suppressed synthetic radar image. The multi-path virtual image suppression method has the beneficial effects that the suppression of the multi-path virtual image is realized by utilizing the characteristic that the real image positions of the imaging results are completely the same and the virtual image positions are different under the multi-transmitting and single-receiving systems.

The invention discloses a pulse compression double-optical comb frequency modulation continuous wave laser ranging device and method, the device comprises an FMCW light source, a beam splitter, a detection light channel, a reference light channel, a beam combiner and a processing module, the FMCW light source outputs bidirectional linear frequency sweeping laser with the frequency sweeping bandwidth B and the frequency sweeping period 2T, and the bidirectional linear frequency sweeping laser is divided into detection light and reference light through the beam splitter. The detection optical channel, the first optical comb generating the comb tooth interval of fR, the reference optical channel and the second optical comb generating the comb tooth interval of fR + delta fR are used, two paths of signals are combined through the beam combiner and then input to the photoelectric detector to generate beat frequency signals, the processing module carries out rear-end data processing on the beat frequency signals, time domain signal splicing is achieved through the coherence of the double optical combs, and time domain signals are obtained. And the ranging precision is improved. According to the invention, the pulse compression technology is used to reduce the duty ratio of the detection light pulse and improve the ranging resolution; meanwhile, beat frequency signals are generated through the double-optical comb technology, time domain signal splicing is achieved through coherence between different comb teeth, the frequency sweeping bandwidth is equivalently improved, and the distance measuring precision is further improved.

The invention discloses a method, a system and a device for realizing high-repetition-frequency wide-width imaging, and relates to the technical field of high-repetition-frequency wide-width imaging, and the method comprises the steps: carrying out the pulse compression of large-size imaging echo data; setting the number of accumulation frame periods and the number of imaging areas; a first cache, a second cache, a first processing core and a second processing core are arranged, high repetition frequency imaging accumulation is conducted on pulse pressure data of multiple accumulation frame periods through the first cache, the second cache, the first processing core and the second processing core, and high repetition frequency imaging accumulation results corresponding to multiple imaging areas are spliced. Based on this, the dual-core model separates the control flow and the imaging accumulation process, and the two cores perform parallel processing, so that the processing speed can be improved; an imaging accumulation process is divided into pulse pressure cache and imaging hardcore accumulation by a double-cache technology, and the repetition frequency is improved by optimizing time efficiency through a memory; and the imaging data is divided into a plurality of areas for respective imaging, so that the problem of imaging sheet limitation can be solved.

The invention discloses an ISAR (Inverse Synthetic Aperture Radar) multi-pulse accumulation cross-correlation distance and phase correction system based on an FPGA (Field Programmable Gate Array). The ISAR multi-pulse accumulation cross-correlation distance and phase correction system comprises an upper computer and the FPGA, the upper computer is used for controlling the inverse synthetic aperture radar system to transmit a signal and receiving an echo signal; performing de-line frequency modulation on the echo signal to obtain an echo signal after pulse compression, and preprocessing the echo signal to obtain a to-be-processed echo signal; quantizing the echo signal to be processed, acquiring a quantized echo signal, transmitting the quantized echo signal to the FPGA, and receiving the distance returned by the FPGA and the echo signal after phase correction; and the FPGA is used for executing a multi-pulse cumulative cross-correlation envelope alignment algorithm to perform alignment processing on the quantized echo signal, obtaining a corrected echo signal and returning the corrected echo signal. The register transfer stage circuit based on the multi-pulse cumulative cross-correlation envelope alignment algorithm is designed based on the FPGA, high-parallelization acceleration based on the multi-pulse cumulative cross-correlation envelope alignment algorithm module is achieved, and the processing speed and efficiency of the algorithm are remarkably improved.

The invention provides a radar signal multi-target tracking method and system based on a dynamic graph convolutional network. The method comprises the following steps: acquiring a radar one-dimensional range profile sequence of a target cluster, and performing pulse compression to form a radar echo two-dimensional sequence; separating position and amplitude data of aliasing scattering points based on scattering point distribution characteristics; calculating a spatial distance between targets by using position information, constructing a dynamic edge weight in combination with a radial speed difference, and generating a shielding relation edge; aggregating neighborhood features through a dynamic graph convolutional network, and learning trajectory decoupling features of the occlusion and intersection regions; and generating association weights based on the decoupling features, inputting the association weights into a multi-hypothesis tracking algorithm, generating a multi-branch trajectory, and if the spatial distance between two branches is smaller than a dynamic threshold value and the velocity vector included angle exceeds a set angle, retaining a branch with a higher association weight, and outputting a multi-target trajectory sequence. According to the invention, the multi-target tracking precision and robustness in a shielding and trajectory crossing scene are significantly improved.

The invention discloses an airborne radar moving target detection method and system based on distance-Doppler characteristics, and the method comprises the steps: building an airborne pulse Doppler radar echo signal model, and generating a large number of echo signals through simulation; performing pulse compression processing and frequency domain filtering processing on the machine echo signal to obtain a two-dimensional distance-Doppler image; processing the two-dimensional distance-Doppler image to obtain a processed distance-Doppler image; a generalized target is defined, the generalized target is marked on the processed distance-Doppler image, and a marked data set is generated; training a deep neural network model by using the labeled data set to obtain a trained deep neural network model; and by using the trained deep neural network model, target detection is performed on an actual airborne pulse Doppler radar distance-Doppler image, so that the working performance of an airborne radar system under clutter and interference conditions is greatly improved, and the minimum detectable speed limitation of the system is broken through.

The invention provides a target positioning method and system based on a distributed networking radar system, and belongs to the technical field of radars, and the method comprises the steps: controlling a plurality of radar nodes to transmit stepping linear frequency modulation continuous wave pulse signals, and collecting target echoes; carrying out band-pass filtering, pulse compression and fast time synchronization processing on the echoes, and generating interference-free data through a moving target extraction algorithm; realizing cross-node clock synchronization based on a moving target behavior cognition model and a template matching algorithm; constructing a multi-node distance estimation equation set, generating an accurate distance value through calibration broadband synthesis and FFT, and determining a target three-dimensional coordinate; and generating a motion track and speed prediction through Kalman filtering based on the target position sequence. The system comprises a signal emission and acquisition module, a signal processing module, a clock synchronization module, a distance estimation and coordinate fusion module and a trajectory prediction module. The method supports multi-target tracking, improves positioning precision and time synchronization precision, has few errors, and is compatible with any node deployment form.

The invention belongs to the technical field of radial artery compression hemostats, and particularly relates to a radial artery hemostasis method based on real-time pulse analysis and a hemostat control system. A slow and continuously changing force is applied to a radial artery puncture opening through the pressure applying module, meanwhile, the pulse detection module transmits a pulse forced feedback signal of the puncture opening to the main control module in real time, and the main control module analyzes and processes the received feedback signal in real time and judges the current hemostatic state of the radial artery. And on this basis, the pressure applying module is controlled to adjust the pressure. The method is characterized in that the relation between pulse forced feedback signals and the forced state of the radial artery is obtained through clinical tests according to the difference of the pulse feedback signals of the radial artery in different pressed states, and therefore the pressure is stabilized in the state that the blood flow of the radial artery is stable and a puncture opening does not bleeding. According to the scheme, the individual difference between different patients can be overcome, the compression hemostasis strength is adjusted in a self-adaptive mode, and the occurrence rate of related complications such as radial artery occlusion is effectively reduced.

The invention discloses a subaperture self-focusing CSAR imaging method combined with topographic relief error compensation, which comprises the following steps of: reading digital elevation model data of an observation scene, supplementing height direction information for grid points of an imaging area, and eliminating height direction errors; an echo signal acquired by the CSAR is converted into a frequency domain, multiplied by a reference signal and converted into a time domain signal, and range pulse compression is completed; segmenting the full-circumference aperture into a plurality of non-overlapped sub-apertures, and imaging the sub-aperture data by using a backward projection algorithm to obtain a sub-aperture image; a self-focusing algorithm based on an image sharpest criterion is adopted to process each sub-aperture image to carry out motion error compensation, phase errors are estimated, and iteration estimation is carried out for multiple times; and performing accumulation processing on the sub-aperture images after the self-focusing processing to obtain a high-precision full-aperture CSAR image. Compared with the prior art, the precision and quality of CSAR imaging can be improved by combining topographic relief error compensation and sub-aperture self-focusing processing.

The invention provides an ultrasonic detection method for internal defects of an insulating part of a power system based on a piezoelectric ultrasonic transducer, and belongs to the technical field of insulating part detection. After wavelet denoising and deep attenuation compensation are carried out on echo signals, sound path distance time delay and sound pressure amplitude parameters are extracted, defect identification and position estimation are carried out by utilizing a layered variational auto-encoder, a high-frequency transducer is switched to aiming at tiny defects, a harmonic component is extracted by adopting a nonlinear ultrasonic method, and a characteristic size is calculated; a defect distribution space feature matrix is generated based on a synthetic aperture focusing technology, a unified or personalized processing strategy is selected according to an acoustic characteristic homogenization degree evaluation value, a complete defect detection result is output, and the technical problem that deep weak defects in the electric insulation part are difficult to accurately detect and recognize is solved.

The invention relates to the field of radar detection and signal processing, and particularly discloses a radar data technology system for monitoring a tiny target, and the system comprises a signal receiving and transmitting module which is used for generating and transmitting a linear frequency modulation signal based on a linear frequency modulation technology, and receiving an original echo signal reflected by the target; the pulse compression processing module is used for performing complex convolution operation on the original echo signal based on a matched filter to generate a compressed pulse signal; the multi-pulse coherent accumulation module is used for performing frequency domain energy accumulation on a plurality of compressed pulse signals of the same distance unit based on a discrete Fourier transform technology; and the Kalman filtering tracking module is used for processing the signals after multi-pulse coherent accumulation through a Kalman filtering algorithm, predicting and updating a target state in real time, and generating final trace point data. According to the invention, through key technologies of large-time wide-bandwidth pulse compression, multi-pulse coherent accumulation and the like, the detection capability of the radar on a tiny target is remarkably improved.

The embodiment of the invention provides a radar signal processing system and method, and relates to the field of radar signal processing, the system comprises an ARM processor and a field programmable gate array, the ARM processor comprises a first processor and a second processor, the field programmable gate array is used for carrying out AD sampling, data preprocessing, pulse compression, fast Fourier transform and CFAR detection on received radar echo signals to obtain target radar echo signals, and the first processor is used for dividing the target radar echo signals into first target radar echo signals and second target radar echo signals; the first processor is used for carrying out target identification based on the first target radar echo signal to obtain a first identification result, the second processor is used for carrying out target identification based on the second target radar echo signal to obtain a second identification result, the first identification result and the second identification result are fused to obtain a final detection result, and the radar signal processing efficiency can be improved.

The invention discloses an echo segmented pulse compression method under a high sampling rate based on an FPGA (Field Programmable Gate Array). According to the method, down-sampling preprocessing is firstly carried out on the signals sampled by the ADC with the sampling rate of 124 MHz, the sampling rate is reduced to 62 MHz on the premise that spectrum aliasing does not happen to the signals, then segmentation range pulse compression is carried out on the 1PRT echo signals, the total processing amount is reduced by 40%, the data calculation amount can be remarkably reduced, the operation speed and the data processing efficiency can be improved, and the method is suitable for large-scale popularization and application. And FPGA logic resources are saved. And short-time 1s echo pulse compression preprocessing is realized by adopting a method of synthesizing 1000 PRTs, so that the communication data rate is greatly reduced. And in cooperation with operation of other components of the surface scene deformation monitoring system, the system reliability is improved, and the scene deformation monitoring task can be smoothly carried out.

The application discloses a method for simultaneously resisting suppressing interference forward-looking imaging of a missile-borne forward-looking array radar, adopts an array antenna in a cut-off track direction to receive echoes of a forward-looking area, and samples to obtain distance-pulse-array three-dimensional echo data; pulse compression in the distance direction is performed on the three-dimensional echo data, a pulse compression reference function and a migration correction factor are multiplied in the frequency domain, and high resolution in the distance direction is realized; multi-channel receiving data of each distance-pulse unit is selected, and is sequentially arranged to form a corresponding space snapshot of the unit; a covariance matrix of interference and noise is established, and the maximum likelihood estimation value of the target angle and amplitude in the interference environment is approximately solved by using an adaptive single-pulse algorithm on the space snapshot signal of each distance-pulse unit after distance pulse compression; and the angle measurement result is projected to the distance-azimuth domain, and through space coordinate conversion, a two-dimensional forward-looking imaging diagram is obtained. The application realizes high-resolution imaging of a forward-looking target while effectively suppressing main lobe suppressing interference.

The invention relates to a wind profile radar signal and data processing method and system, and the method comprises the steps: constructing a working parameter combination of a wind profile radar, and designing a radar detection mode of the wind profile radar based on the working parameter combination; the wind profile radar collects external wind field data based on the radar detection mode to obtain a wind profile radar signal; performing signal processing based on the obtained wind profile radar signal; performing pulse compression, moving target detection and Doppler spectrum analysis on the wind profile radar signal; extracting wind profile radar data from the processed wind profile radar signal, and processing the wind profile radar data; performing wind field inversion and quality control on the wind profile radar data; and constructing a three-dimensional wind field based on the processed wind profile radar data. According to the scheme, complete acquisition of weak meteorological echo signals under a clear sky condition is effectively ensured, and the accuracy of wind field inversion is improved.

The invention belongs to the field of particle accelerator microwaves, and particularly relates to a C-band compact spherical microwave pulse compression device which comprises a shell, a dual-polarization mode coupler and a circular waveguide, a spherical energy storage cavity is formed in the shell, and the circular waveguide and the spherical energy storage cavity are communicated through a coupling hole; the dual-polarization mode coupler comprises a rectangular waveguide, a butterfly-shaped matching section and a cylindrical matching section. According to the klystron radio frequency pulse compression circuit, the radio frequency pulse with the pulse width of 2.5 microseconds of the klystron can be compressed to 300ns, the average power gain in a single pulse is more than 4 times, the peak power gain is 6.3 times, and the compression efficiency is about 54%. According to the dual-polarization mode coupler, the functions of power distribution, mode conversion and polarization mode generation are synchronously realized, a TE10 mode in a rectangular waveguide is converted into two polarization TE11 modes which are equal in amplitude and orthogonal in phase, and then the two orthogonal TE114 modes are excited in a spherical energy storage cavity.

The invention discloses a generating device capable of generating an ultra-flat broadband micro comb. The generating device comprises a pump pulse generating module, a micro comb generating module and a micro comb generating module, the pumping pulse compression module is connected with the pumping pulse generation module; the high-Q-value microcavity module is connected with the pumping pulse compression module; and the micro comb detection and feedback module is respectively connected with the high-Q-value micro-cavity module and the pump pulse generation module, and is used for monitoring the output spectrum and power change of the high-Q-value micro-cavity module and adjusting the output wavelength of the picosecond pulse light according to the output spectrum and power change so as to stabilize the ultra-flat broadband micro comb. By arranging the high-Q-value micro-cavity, the spectral bandwidth of the micro-comb can be effectively expanded, and the ultra-flat broadband micro-comb is output; meanwhile, the defects that the hyperbolic secant single soliton micro-comb is poor in flatness and narrow in bandwidth are overcome, and the micro-comb has obvious advantages in the application field with high requirements for the flatness and the spectral bandwidth at the same time.

The invention discloses an inter-pulse parameter agility-based intra-pulse stepping LFM (Linear Frequency Modulation) signal design and intermittent sampling and forwarding interference resisting processing method, which comprises the following steps of: generating an inter-pulse parameter agility intra-pulse stepping LFM signal, dividing a pulse signal in each pulse repetition interval into M linear frequency modulation sub-pulse signals, the center frequency of each sub-pulse signal has a frequency interval delta f, and the frequency interval delta f among N PRIs in one coherent processing time is agile; a receiving end receives the echo signal subjected to intermittent forwarding interference, and performs down-conversion to convert the echo signal into a baseband signal; the N PRI echo signals are subjected to segmented pulse compression of sub-pulses, the sub-pulses of the interfered frequency band are found out according to the pulse compression result, and the interfered frequency band is filtered and removed; carrying out whole-section pulse compression on the echo signal after interference elimination again; and finally, performing inter-pulse coherent accumulation on the pulse pressure results of the N PRIs. The method solves the problem that the waveform design is relatively single.

The invention belongs to the technical field of waveform design, and particularly relates to a multi-factor adjustment phase function high main lobe and side lobe ratio nonlinear frequency modulation signal design method. The method comprises the following steps: determining a signal parameter; introducing a sequence factor design sequence function according to the signal parameters; introducing a slope factor and an amplitude factor to design a phase function according to the sequence function, and adjusting the sequence factor, the slope factor and the amplitude factor of the phase function according to the criteria of adherence to constant modulus constraint, improvement of main and side lobe ratio after pulse compression and no undersampling to obtain a final phase function; and according to the final phase function, generating a nonlinear frequency modulation signal with a high main-side lobe ratio.

The application discloses a dual-channel parallel detection airborne phased array radar ground moving target extraction method, comprising the following steps: acquiring coherent pulse train data of an airborne phased array radar; forming sum-difference beam data according to preset sum-difference beam weighting coefficients; constructing a pulse compression matching function to perform pulse compression on the sum-difference beam data; performing platform motion compensation and pulse Doppler processing on the pulse compressed sum-difference beam data; performing high-speed channel determination according to amplitude statistical results of each Doppler unit of the sum beam, and performing CFAR detection; performing low-speed channel determination according to the amplitude statistical results of each Doppler unit of the sum beam, processing low-speed channel data by using sum-difference 3DT-STAP algorithm, and performing CFAR detection and amplitude normalization processing on the processed data; merging the CFAR detection results of the high-speed channel data and the CFAR detection and amplitude normalization processing results of the low-speed channel data, and extracting a point track.

The invention discloses a bistatic radar high-speed target detection method based on space-time Doppler coherent accumulation, and the method comprises the steps: building a bistatic array radar system signal echo model, and carrying out the pulse compression processing of radar echo data; based on the array receiving signal, the direction matrix of the receiving beam and the corresponding weight vector, performing simultaneous multi-beam forming processing on the signal after pulse compression to obtain a signal after beam forming; constructing a beam compensation function; performing transformation compensation on the signal after beam forming by using a beam compensation function to obtain a signal after beam walking correction; performing line demodulation processing on each beam of the signal after beam walking correction to obtain a two-dimensional signal of a distance-modulation frequency domain; and detecting to obtain a target detection result. According to the method, the effects of range migration, pitching beam migration, azimuth beam migration and Doppler frequency migration can be effectively eliminated, the detection performance of the high-speed moving target is improved, and accurate positioning and speed estimation of the high-speed moving target are realized.