346 results about "Main lobe" patented technology

The invention discloses a phased array weather radar calibration method based on a generalized metal ball calibration theory. Comprising the following steps: in a microwave anechoic chamber, collecting two-dimensional antenna pattern data of a phased array weather radar in at least one working mode and pointing to a plurality of different beams; performing numerical integration on the two-dimensional antenna pattern data, calculating a combined beam main lobe solid angle of the transmitting antenna and the receiving antenna, and calculating an equivalent beam width product; calculating a calibration theoretical reflectivity factor of the metal ball based on the product of the theoretical radar scattering sectional area and the equivalent beam width of the metal ball; actual detection echo data of the phased array radar on the metal ball under different working modes and beam pointing is acquired, and an actual reflectivity factor is calculated; and comparing the actual reflectivity factor with the calibration theoretical reflectivity factor to complete calibration of the phased array weather radar. Aiming at the non-Gaussian working mode of the phased array weather radar, the reflectivity factor of the phased array weather radar can be quantitatively evaluated, and the radar detection performance is improved.

The invention relates to the technical field of radar waveform optimization, in particular to a synthetic broadband waveform optimization method based on reinforcement learning. According to the method, a deep reinforcement learning framework is adopted, and end-to-end optimization is carried out on the center frequency and amplitude parameters of multiple sub-pulses. The method comprises the following steps: constructing a synthetic broadband waveform signal model, and parameterizing sub-waveforms to determine a search space of an optimization problem; converting a waveform optimization problem into a reinforcement learning form, and defining a state space, an action space, a reward function and a state transition mechanism; based on a deterministic soft action value iteration strategy algorithm, point spread function features are extracted in combination with a Transform encoder, and sub-pulse parameters are dynamically adjusted. Through the method, the main lobe resolution can be effectively suppressed and improved, the target detection performance of a radar system is improved, and the method has good global optimization capability and environmental adaptability and is suitable for cognitive radar and adaptive waveform design scenes.

The invention provides a passive antenna array beam forming test method and system, and relates to the technical field of beam forming test. According to the method, channel baseline parameters are established in a silencing environment, frequency hopping and channel switching are combined to realize multi-frequency-point synchronous sampling, a reference source and self-polling data are utilized to calculate a mutual coupling correction matrix and a feeder line consistency factor, and weight projection and equivalent aperture field generation are completed without changing physical wiring conditions; further extracting a main lobe direction, a beam width, a side lobe level and a scanning consistency index through far field transformation, and unwrapping and smoothing a frequency-point-crossing phase result; and meanwhile, generating a unique traceability identifier, establishing full-link association between a test condition and a result, and outputting a criterion conclusion. According to the method, the accuracy, efficiency and traceability of passive array beam testing are improved.

The invention discloses a harmonic and inter-harmonic parameter detection method and device based on a self-multiplication convolution window algorithm, and belongs to the field of signal detection, and the method comprises the steps: obtaining a discrete time domain signal, and carrying out the windowing and mapping of the time domain signal based on the self-multiplication convolution window algorithm, and obtaining a frequency domain signal; calling a quantum particle swarm algorithm to estimate the frequency domain signal to obtain an estimation parameter matched with a preset frequency spectrum; and performing nonlinear error compensation on the estimation parameter by using a preset space-time attention residual network to obtain harmonic and inter-harmonic parameters. According to the method, signal leakage can be suppressed by windowing the signal, the energy of the main lobe of the frequency spectrum is more concentrated, the frequency domain signal is estimated by using the quantum particle swarm algorithm, the evaluated frequency spectrum meeting the actual demand can be quickly screened, and finally, the frequency spectrum is compensated, so that the error can be further reduced, and the detection precision can be further improved.

The invention relates to a time domain broadband adaptive beam forming method and system based on Chebyshev weighting, and belongs to the field of array signal processing. Aiming at the technical problems of poor real-time performance and high sidelobe of the existing broadband beam forming, the method comprises the following steps of: dividing a received broadband signal into a plurality of sub-bands, obtaining an optimal weight vector for each sub-band by adopting a minimum linear constraint iterative algorithm after down-conversion, constructing an expected response of an FIR filter according to each weight, obtaining a filter coefficient through L2 norm convex optimization, and finally obtaining a high sidelobe beam according to the expected response of the FIR filter. And performing time domain weighting on each array element signal by using a filter bank, and outputting a directional beam. According to the method, the calculated amount is low, a main lobe and interference null can be formed in real time in a broadband, and a certain side lobe height is kept.

The invention discloses a non-line-of-sight moving target three-dimensional reconstruction method based on an MIMO millimeter wave radar, and is applied to the technical field of radar target detection in a complex urban environment. Aiming at the problem of difficulty in realizing three-dimensional reconstruction of a non-line-of-sight moving target in the existing radar target detection technology, the method comprises the following steps: firstly, establishing a non-line-of-sight multipath propagation model, and exporting a multipath signal model of an MIMO millimeter wave radar; the invention further provides a multipath signal departure angle (DoD) / arrival angle (DoA) unambiguous estimation algorithm, and solves the problem that a main lobe and a grating lobe are difficult to distinguish in the DoD / DoA estimation process of an existing commercial MIMO radar. And finally, proposing a path-oriented non-line-of-sight target three-dimensional positioning algorithm, respectively positioning the non-line-of-sight target by using different paths, and fusing different path positioning results to form a three-dimensional point cloud. According to the method, three-dimensional reconstruction of a plurality of non-line-of-sight moving targets can be realized, and the correlation problem between paths does not need to be considered.

The invention discloses a Shack-Hartmann wavefront detector centroid calculation method and related equipment, and relates to the field of optical measurement, and the method comprises the steps: obtaining a light spot array grayscale image, detecting the local maximum value of each light spot, and dividing sub-aperture image regions corresponding to micro lenses one by one according to the local maximum value; extracting a gray matrix of each sub-aperture image region, respectively determining one-dimensional regions of a light spot main lobe in row and column directions, and intersecting to obtain a main lobe region; a main lobe area is deducted from the sub-aperture image area to form a threshold calculation area, and the maximum gray value of the threshold calculation area is selected as a threshold; and performing threshold reduction on pixels in the sub-aperture image area, setting a negative value to zero, and calculating the position of the mass center of the light spot based on the processed image. According to the method, sub-aperture adaptive threshold and local background removal are realized, weak light spot information loss caused by a unified threshold is avoided, and the precision of centroid calculation and wavefront restoration is improved.

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 the technical field of radar information, in particular to a ground clutter suppression method for a ground reconnaissance radar, which comprises the following steps of: firstly, establishing a clutter profile map by using echo data, judging information inside and outside a clutter according to the clutter profile map, and selecting different signal processing flows, namely, adopting a detection channel 1 outside the clutter, adopting a detection channel 2 and a detection channel 3 inside the clutter and adopting a detection channel 2 and a detection channel 3 outside the clutter; after the detection channel 1 passes through the MTD filter, clutter suppression processing is not carried out, and a detection result is output; the detection channel 2 is a coherent processing channel, firstly performs mean filtering processing, then performs coherent processing, performs clutter suppression processing through phasor mean filtering, and outputs a detection result; and the detection channel 3 is a zero Doppler processing channel and is used for detecting a low-speed target in a clutter area, compared with the prior art, the method can reduce Doppler sidelobes as much as possible on the premise of ensuring that the ground clutter height is suppressed, and has the minimum main lobe width and the minimum signal-to-noise ratio loss.

The invention provides a bistatic synthetic aperture radar track planning method and system based on structure driving, and relates to the technical field of radar track planning, and the method comprises the steps: building a BiSAR echo model based on a target scattering model; analyzing the imaging characteristics of the target under different configurations, and revealing the constraint relationship between the target structure representation and the configuration; constructing a structure-driven multi-stage trajectory planning model based on the constraint relationship between the target structure representation and the configuration; the trajectory optimization is modeled as a multi-objective optimization problem; through a non-dominated sorting genetic algorithm based on target scattering characteristic driving, a multi-target optimization problem is solved so as to plan a platform track in each stage. According to the method, the limitation of a point target model in an existing trajectory planning method can be broken through, all main lobe observation configurations capable of presenting target structure information are optimized, the retention degree of the target structure information in a BiSAR imaging result is effectively improved, and the interpretability of the image is remarkably enhanced.

The invention discloses a main lobe gain maximization method for an analog-digital hybrid array of a radar communication system. According to the method, the ratio of the maximum minimum main lobe level to the peak side lobe level is used as a target function, and under the main lobe ripple constraint, the simulation weight constant modulus constraint and the digital weight power constraint, the ADMM (Alternating Direction of Multiplexing) is used for carrying out joint design on the simulation weight and the digital weight. In the ADMM framework, a Riemann conjugate gradient method is adopted to solve a simulation weight subproblem with constant modulus constraint; and solving a digital weight by adopting a Lagrange multiplier method. A numerical result shows that the method can generate better main lobe ripples and lower peak side lobe level, and has good beam directional diagram accurate control performance.

The invention discloses a radar measurement method, device and equipment, a medium and a product, and relates to the technical field of radar signal processing. According to the method, a space angle is divided into a main lobe area and a side lobe area; determining a phase modulation strategy of twice observation of the radar; the phase modulation strategy comprises the steps that phases of a main lobe area are kept consistent in two observations, and the phase difference of a side lobe area is 180 degrees; according to a phase modulation strategy, determining a directional diagram of expected radiation of the array antenna in two times of observation, and optimizing a unit excitation weighting vector in two times of observation to obtain an optimized value of the unit excitation weighting vector; according to the optimization value, performing phase modulation on a transmitting signal of the array antenna; and coherent superposition is carried out on echo signals reflected by the target and received by the radar in two times of observation. On the premise that the array size is not changed, the anti-interference capability and the spatial resolution of the radar are remarkably improved, and the monitoring precision of the radar on parameters such as distance, speed, deformation and angle is effectively improved.

The invention provides an anti-noise interference frequency parameter estimation method for high-precision optical coherence ranging, which comprises the following steps: acquiring a spectral interference signal of an optical low-coherence interference system and a reference light spectral signal output only by a reference arm, and converting the spectral interference signal into interference signals with wave number space arranged at equal intervals, carrying out spectral density amplitude normalization to obtain a standard interference signal so as to eliminate interference of light source spectrum fluctuation and non-uniform sampling on frequency estimation; hanning window modulation is applied to a standard interference signal, spectrum leakage is suppressed, spectrum analysis is performed on the modulated signal, a peak value and an adjacent secondary peak value of a spectrum main lobe are extracted, a frequency correction amount is calculated based on a peak value and secondary peak value amplitude ratio relation derived by a Hanning window spectrum mode function, and an accurate frequency of the interference signal is obtained; and calculating the displacement of the object to be measured according to the product of the accurate frequency and the spectral resolution of the optical low-coherence interference system in combination with the refractive index of the light in the measurement medium.

A system and method for distinguishing targets of interest from main lobe clutter and sidelobe clutter includes an ESA or AESA divided into subarrays. A sum beam power profile is produced via one or more scans of the subarrays, and a difference beam power profile is produced via calculations involving the subarrays. A comparison of the sum beam power profile and the difference beam power profile accentuates signal power disparities between targets of interest and clutter. A threshold is then applied to isolate targets of interest. Different difference beam power profiles may be used for elevation comparisons and azimuth comparisons. Alternatively, subarrays may be selected such that the same difference beam power profile may be used for both elevation and azimuth. Scans may be time multiplexed such that data from different scans may be used to produce the sum beam power profile, the difference beam power profile, or both.

According to the SAR anti-interference method based on the multiple orthogonal frequency modulation waveform design disclosed by the invention, the waveform agility number and orthogonality can be improved while the low sidelobe imaging performance is ensured; in addition, according to the method, a segmented high-degree-of-freedom frequency modulation coding structure is adopted, and the long-distance imaging requirement of a satellite-borne SAR system under the condition of a large time bandwidth product can be met. The method comprises the following steps: S1, constructing a multi-target signal optimization model for minimizing a peak sidelobe ratio and cross-correlation peak energy; s2, designing an improved adaptive genetic algorithm for solving a non-convex complex waveform optimization problem; s3, an MOFM waveform with accurate spectrum control capability is obtained through algorithm optimization; s4, effective suppression of main lobe active interference is realized by using the designed waveform; compared with a traditional linear frequency modulation waveform, the method has the advantages that the low sidelobe characteristic is kept, meanwhile, the orthogonal agility number is remarkably increased, and the method is suitable for the anti-interference imaging requirement of a modern spaceborne SAR system.

A quad-polarized antenna system according to the present invention comprises a plurality of RF chains, and an antenna array in which rows of first dual-polarized antenna units and rows of second dual-polarized antenna units are alternately arranged in a horizontal direction. The first dual-polarized antenna unit and the second dual-polarized antenna unit have different dual polarization characteristics from each other. The rows of first dual-polarized antenna units are used to form at least one first beam and at least one second beam which have + / −45° polarizations, and the rows of second dual-polarized antenna units are used to form at least one third beam and at least one fourth beam which have 0° / 90° polarizations. The first beam, the second beam, the third beam, and the fourth beam are formed towards different spatial directions, and the first and third beams correspond to main lobes, and the second and fourth beams correspond to grating lobes.

The invention discloses a microphone array layout optimization method based on IGSA, and belongs to the field of sound source localization. The method comprises the following steps: firstly, constructing a topological structure of a microphone array as a rectangular array; then, the directivity and the directional diagram of the microphone array are adopted to express the performance of the microphone array; constructing a fitness function through the width of a main lobe, the level of a side lobe and the number of microphones; then, on the basis of a genetic algorithm, improving crossover and mutation steps, adopting a hierarchical crossover strategy and a similarity regulation and control mutation strategy, and simultaneously optimizing an array structure by a simulated annealing operator in an interspersed manner; and finally, outputting the optimal microphone array arrangement to meet the requirements of low sidelobe performance and high resolution. The IGSA algorithm is adopted to optimize the microphone array layout, so that more accurate global optimization, faster convergence speed and better multi-target balance are realized, and particularly, the number of microphones and the hardware cost are remarkably reduced while the sound source localization performance is ensured.

The invention relates to the technical field of radars, in particular to a weather radar distance resolution calibration method and system. The method comprises the following steps: collecting oversampling original baseband I / Q data of a point target in a plurality of continuous pulse periods; determining a pulse signal-to-noise ratio, and screening out effective pulses according to a threshold value; carrying out sub-sampling stage time alignment on the effective pulses based on cross-correlation analysis, and carrying out incoherent averaging on power module values of all the aligned pulses to generate an average pulse power envelope; converting the average pulse power envelope to a logarithm domain, and selecting discrete data points in a main lobe region; according to the discrete data points, a nonlinear least square method is adopted to carry out iterative fitting on the generalized Gaussian mathematical model, and a continuous analytic function describing the pulse envelope is obtained; according to the continuous analytic function, determining a pulse time width when the power is reduced to a peak value of-6dB; and determining the real distance resolution according to the pulse time width. The measurement robustness is improved, and sub-meter calibration precision is achieved.

The invention discloses an archive room full life cycle management system based on a radio frequency identification technology, and relates to the field of archive management, the optimal weight vector of each reader-writer antenna array is obtained through a minimum mean square error algorithm, the transmitting phase and amplitude of each node signal are accurately adjusted according to the optimal weight vector, and in the spatial dimension, the optimal weight vector of each reader-writer antenna array is obtained. Through cooperative control and spatial filtering of beams transmitted by a plurality of distributed reader-writer nodes, beam main lobe energy is converged to a target passive RFID electronic tag, a radiation zero point is formed in the direction of a metal file cabinet, meanwhile, spatial power superposition and directional interference suppression are realized, multipath reflection interference in a metal environment is reduced, and the reliability of the metal file cabinet is improved. The signal-to-noise ratio of the label is fundamentally improved, the response rate of the label is ensured to be improved to 98% or above through a dynamic frequency modulation mechanism, and the problem of signal multipath reflection caused by a metal file cabinet is effectively solved.

The invention discloses a method for realizing elliptic cone scanning by a communication-in-moving antenna. The method comprises the following steps: determining the value of a scanning position point number parameter N; determining the value of the maximum scanning offset angle delta A in the azimuth angle direction and the value of the maximum scanning offset angle delta E in the pitch angle direction; determining values of an expected azimuth angle alpha 0 and an expected pitch angle beta 0 of the current antenna; setting a scanning counter i; when i is less than 4N, calculating a parameter theta i, calculating a scanning offset angle delta i, calculating a scanning track beta i of a pitch angle, and calculating a scanning track alpha i of an azimuth angle; the pitch angle of the antenna is controlled to rotate to a new position beta i, and the azimuth angle of the antenna is controlled to rotate to a new position alpha i; and updating the scanning counter i, i = mod (i + 1, 4N), and returning to execute. The method not only can realize elliptic cone scanning, but also can realize cone scanning, and can effectively solve the problem that the average receiving level is reduced when the communication-in-moving antenna of which the cross section of the beam main lobe is elliptic performs cone scanning.

The invention relates to the technical field of seismic exploration, in particular to a method for determining structural parameters and sweep frequency signals of a controllable impact seismic source, which is used for carrying out an indoor physical test of a controllable impact seismic source model machine and ensuring the effectiveness of a design scheme of the controllable impact seismic source. Constructing and verifying a multi-body dynamics numerical model of single impact, performing single variable sensitivity analysis on key structure parameters, and determining an optimal structure parameter combination by taking a frequency domain of output seismic waves as an evaluation index; constructing a multi-impact model, performing a simulation test on the sweep frequency control parameter, and determining an optimal sweep frequency signal parameter based on the main lobe amplitude and the main lobe-side lobe amplitude ratio of the output signal autocorrelation function; through forward modeling and cross-correlation-scattered wave inversion imaging processing, an application method of a controllable impact seismic source is established, and validity is verified. The technical problems that a traditional trial and error method is low in efficiency, main lobe energy of seismic source output signals is dispersed due to an unknown parameter influence mechanism, side lobe interference is large, and the signal-to-noise ratio is low are solved.

The invention discloses a main lobe suppression type polarization agility interference suppression method, which aims at main lobe suppression type interference with polarization parameters dynamically changing, and constructs a transient polarization projection vector IPPV of an orthogonal polarization receiving signal based on the orthogonal polarization receiving signal of a dual-polarization radar. And detecting polarization parameter abrupt change points of the orthogonal polarization receiving signals by adopting a heuristic segmentation algorithm, and segmenting the orthogonal polarization receiving signals by using the polarization parameter abrupt change points to obtain polarization segmented receiving signals. And aiming at polarization segmented receiving signals with different polarization parameters, obtaining interference cancellation parameters and carrying out interference suppression by utilizing a self-adaptive polarization cancellation algorithm based on a minimum variance criterion to obtain interference suppression signals. According to the interference cancellation parameters of different polarization segment receiving signals, amplitude and phase compensation is carried out on the interference suppression signals, reference signals for pulse compression are reconstructed, and after pulse compression processing is carried out, main lobe suppression type polarization agility interference cancellation and target detection are achieved.

The invention provides a radar antenna structure damage and function damage mapping evaluation method and system based on a subarray-level equivalent target, and relates to the technical field of radar antenna damage effect evaluation. According to the method, a baseline parameter set is formed through standardized filing of functional parameters of an equivalent target array structure, damage is loaded and damage parameters are collected under a preset working condition, main lobe gain, beam width, side lobe level and beam pointing are tested, functional variable quantity is calculated, array surface damage is divided and coded through a two-dimensional matrix and blocks, and standardized input is generated. A quantitative mapping model is established, and through cross validation, residual analysis optimization and adaptive updating, high-precision and traceable evaluation of structures and functions under multiple working conditions is realized, and support is provided for criterion optimization and anti-damage design.

The invention belongs to the technical field of extrusion process monitoring, and particularly relates to a cable extrusion process state online monitoring method and system based on acoustic sensing, so as to solve the technical problem of inaccurate cable extrusion process state monitoring in the prior art. The monitoring method comprises the following steps: S1, when a transient impact factor is greater than a preset threshold value, windowing a signal frame by adopting an asymmetric window function with a main lobe in front and a side lobe in back; s2, performing fast Fourier transform on each windowed signal frame to obtain a frequency spectrum of each windowed signal frame; filtering the frequency spectrum of each signal frame by using a filter bank and calculating logarithmic energy of each filtering channel; s3, selecting cepstrum coefficients of which the ratio is greater than a selection threshold to form a process state feature vector; and inputting the process state feature vector into a state classifier to obtain a current cable extrusion process state. According to the method, redundancy and noise interference are eliminated, so that the accuracy of process state monitoring is improved.

The invention discloses a transceiving full-duplex dual-mode three-beam radio frequency component architecture and system, relates to the technical field of radio frequency communication and radar perception integrated front ends, and comprises the following steps: improving the stability of a system power-on process by combining an FPGA (Field Programmable Gate Array) unified trigger mechanism with graded power-on time sequence control of a radio frequency switch, a power amplifier and an LNA (Low Network Alliance); flexible reconstruction of channels 1-4 is realized through combination of a 2 * 2 switch matrix structure and dynamic interconnection of a circulator and a dual circular polarization port, real-time rotation of a polarization state and dynamic adjustment of a beam main lobe direction are realized through combination of a Berry geometric phase algorithm and a dual-stage regulation and control strategy of a reflection array rotation element, the flexibility of beam generation is improved, and the beam generation efficiency is improved. The dual-mode polarization reflection array is combined with the full duplex circulator and the time sequence control module, so that three polarization combination modes under the same hardware platform are realized, and the polarization multiplexing efficiency of the communication system is improved.

The application provides a remote acoustic signal pickup method and system based on phase coding microwave sensing, comprising: constructing a phase coding matrix, and performing phase shift control on the transmission signals of multiple transmission antennas; controlling the multiple transmission antennas to simultaneously transmit a linear frequency modulation continuous wave signal, so that the main lobe of a synthesized beam is directed towards the direction of a to-be-detected acoustic source or the direction of a target medium; using one or more receiving antennas to receive echo signals of the acoustic source target, to obtain a corresponding number of baseband signals; performing acoustic vibration phase demodulation on the corresponding number of baseband signals, to extract vibration information of the surface of the medium target caused by the vibration information of the acoustic source or caused by the excitation of the acoustic wave; and reconstructing the acoustic signal, to realize remote acoustic pickup. The application overcomes the problems of weak echo signals, low signal-to-noise ratio, large adjacent target interference and low quality of reconstructed acoustic signals in remote acoustic pickup, and improves the signal-to-noise ratio and sensing distance of remote acoustic pickup.

This invention provides a method for rapid planar near-field measurement of large-aperture antennas, relating to the field of antenna technology. The method obtains sparse field amplitude and phase information of several sampling surfaces in the near-field radiation region of the antenna under test through large-step uniform sampling. Simultaneously, it samples a finite number of precise field amplitude and phase information points for each sampling surface and obtains the field distribution characteristics by calculating the fluctuation of the amplitude at the sampling points. Based on the sparse field amplitude and phase information and field distribution characteristics of the sampling surfaces, it uses partitioned interpolation and field distribution calibration methods to obtain the initial electric field of each sampling surface. Based on planar wave spectrum theory, iterative numerical calculations are performed on the initial electric field to recover the near-field distribution of each sampling surface. Finally, the far-field radiation characteristics of the antenna are obtained through near-field-to-far-field transformation. This invention can significantly shorten the testing time while obtaining key indicators of the antenna's far-field characteristics, including the normalized radiation pattern main lobe and first sidelobe, 3dB beamwidth, sidelobe level, and axial ratio.

The application discloses a STCA-MIMO radar anti-interference method based on nonlinear time delay, which comprises the following steps: calculating target echo signals based on nonlinear time delay of transmitting array elements; carrying out digital mixing and matching filtering on the target echo signals to obtain preprocessed signals; determining a first transmitting steering vector and a first receiving steering vector according to the preprocessed signals; calculating a covariance matrix of STCA-MIMO radar system receiving data; calculating an adaptive weight vector by using a robust direct data domain beam forming technology based on the covariance matrix and an actual receiving-transmitting joint steering vector of a target; calculating a first receiving-transmitting joint steering vector of the STCA-MIMO radar system; and carrying out beam forming by using the first receiving-transmitting joint steering vector and the adaptive weight vector. The application can effectively suppress interference signals in the main lobe of the STCA-MIMO radar, and solves the problem of the decline of interference suppression performance in the prior art when the interference is located near the distance grating lobe of the main lobe of the real target.

This invention provides a wavefront design method and system based on a space-based early warning radar, including acquiring the system scanning time, radar range-azimuth ground coverage range, beam coverage overlap rate, radar azimuth beam center, and radar initial wavefront near-end down-view angle; determining the 3-dB elevation main lobe beamwidth of the current wavefront based on the near-end down-view angle value of the current range wavefront; determining the far-end down-view angle value of the current wavefront based on the beam center calculation result of the current range wavefront; iteratively updating the near-end down-view angle of the next range wavefront to the near-end down-view angle of the current wavefront, and outputting all range wavefront division results; sequentially calculating the 3-dB azimuth main lobe beamwidth based on the near-end spatial cone angle of each azimuth wavefront, sequentially updating the beam center and far-end down-view angle of the azimuth wavefront, iteratively processing until the azimuth-ground distance meets the given azimuth coverage requirements; and finally outputting the wavefront design calculation results that meet the range-azimuth coverage requirements and the required dwell time for each wavefront.

The invention discloses a fire-fighting fire scene communication device and method suitable for a smog environment, relates to the technical field of fire scene communication, and solves the technical problems that an optimal path is difficult to select, an antenna pattern is reasonably adjusted, obvious defects exist in dynamic nature, anti-interference performance, coverage capability and safety, and fire scene communication safety is affected. The direction of an interference source is monitored in real time through an array antenna, and an antenna pattern is dynamically adjusted in combination with a signal quality evaluation result. And calculating a weight coefficient of an antenna array element by adopting an MVDR algorithm, so that a main lobe direction is aligned with a target signal. And voice and position data are encrypted by adopting a quantum key distribution or post-quantum encryption algorithm, so that malicious interception or tampering in a fire scene is prevented. In combination with a hybrid model of a CNN convolutional neural network and an RNN recurrent neural network, preset fire scene interference noise is specifically identified and removed in real time. And calculating an optimal path from the source node to the target node based on the corrected link cost.