1467 results about "Side lobe" patented technology

The invention discloses an unmanned aerial vehicle signal identification method and system in a complex electromagnetic environment, and belongs to the field of unmanned aerial vehicles. According to the invention, the form of the liquid metal channel of the liquid metal antenna is adjusted to adapt to the target frequency band, and regional electromagnetic signals are collected in all directions. And generating spatial distribution data including the unmanned aerial vehicle and the interference direction based on the phase difference and preset features. The deformation of the liquid metal droplets is regulated and controlled through the electrowetting voltage, so that the antenna main lobe is aligned with the unmanned aerial vehicle, and the side lobe suppression area covers an interference source. Then, a target direction signal set is collected, and time domain fluctuation, frequency domain distribution and spatial domain direction multi-dimensional features are extracted; and inputting the multi-dimensional features into a joint probability model constructed by a Bayesian network, and outputting posterior probability information. Markov chain Monte Carlo self-adaptive sampling is utilized, the classification confidence coefficient is calculated through iterative convergence, the signal category is judged according to a threshold value, and the unmanned aerial vehicle signal recognition accuracy can be improved in the complex electromagnetic environment.

The invention discloses a sparse array antenna optimization method based on an improved zebra algorithm, is used for reducing the peak side lobe level of a sparse array antenna, and belongs to the technical field of radio frequency phased array antennas. The implementation process of the method comprises the following steps: firstly, adding a probability estimation model on the basis of an original zebra optimization algorithm, and converting a real number variable into a binary code; secondly, an adaptive T distribution disturbance strategy and a dynamic selection strategy are introduced, the global search capability of the algorithm is enhanced, the algorithm is prevented from falling into local optimum, and the convergence speed is effectively improved; and finally, an optimal solution is obtained through iterative optimization for a certain number of times. In order to verify the performance of the method, three groups of simulation experiments are carried out, and the result shows that compared with other optimization algorithms, the method can obtain a lower array antenna peak sidelobe level within shorter optimization time, so that the performance of the antenna is improved.

The invention provides a high-resolution positioning method for noise source imaging. The high-resolution positioning method comprises the following steps: designing a sensor array layout and selecting sensors; a multi-channel acquisition synchronous acquisition sensor and records signals to obtain acquisition data; performing signal processing on the acquired data by using adaptive filtering, machine learning calibration, time-frequency analysis and intelligent beam forming technologies to obtain standard data; based on the standard data, performing high-resolution direction estimation by using an optimized multi-signal classification algorithm, and removing a sidelobe effect by using an optimized CLEAN algorithm to complete processing of the standard data; and based on the processed standard data, reconstructing a spatial distribution image of the noise source by using an inversion technology, and dynamically adjusting the resolution of the reconstructed spatial distribution image by using an adaptive algorithm to realize high-resolution positioning of noise source imaging. According to the invention, high-resolution positioning can be realized, the reliability and precision of noise detection are improved, and noise control and management are more effective.

A differential feed waveguide slot antenna array disclosed by the present invention comprises a radiation layer and a feed layer, the radiation layer is provided with a first antenna radiation slot group and a second antenna radiation slot group, the feed layer comprises a one-to-two power divider, a first feed line and a second feed line, one end of the first feed line is connected with a first output end of the one-to-two power divider, and the other end of the first feed line is connected with a second output end of the one-to-two power divider. One end of the second feeder line is connected with the second output end of the one-to-two power divider, the other end of the first feeder line is connected with the other end of the second feeder line, and the length difference X exists between the first feeder line and the second feeder line, so that the phase difference between a first signal passing through the first feeder line and a second signal passing through the second feeder line is 180 degrees; the first antenna radiation slot group is arranged corresponding to the first feeder line, and the second antenna radiation slot group is arranged corresponding to the second feeder line. The antenna has the advantages of wide working bandwidth, low side lobe and low cost.

The embodiment of the invention provides a base station antenna, and relates to the technical field of communication. The base station antenna comprises a housing, a phase shifter and a combiner. The shell is provided with combining cavities and phase shifting cavities, the two phase shifting cavities are arranged side by side in the first direction, the combining cavities are arranged on the same side of the two phase shifting cavities in the second direction in a stacked mode, the first direction is perpendicular to the second direction, and the size of the combining cavity in the first direction is larger than the size of any phase shifting cavity and smaller than the sum of the sizes of the two phase shifting cavities; the phase shifter comprises two phase shifting modules corresponding to the phase shifting cavities, each phase shifting module is arranged in the corresponding phase shifting cavity, and each phase shifting module is provided with a phase shifting network; the combiner is arranged in the combining cavity and provided with a combining network, and the combining network is connected with the two phase shift networks. According to the base station antenna provided by the embodiment of the invention, multi-frequency, miniaturization and integration are realized, the gain, radiation efficiency and sidelobe performance of the base station antenna are optimized, the feed network is simple, and the resonance phenomenon is avoided.

The invention relates to a thin cloth rectangular plane broadband array antenna synthesis method, and belongs to the technical field of array antenna optimization. The method comprises the following steps: firstly, establishing a mathematical model of a rectangular plane broadband array antenna, initializing parameters of the broadband array antenna, and performing sparse processing on a full array by using a Kaiser weighting function; secondly, initializing a sparse array position population by adopting Tent chaotic mapping, calculating an array element to generate a population fitness function value, and recording an optimal individual; thirdly, adopting an improved grey wolf optimization algorithm to carry out sparse optimization on the sparse array, calculating an updated array element fitness value, extracting an optimal fitness value, recording a corresponding array element position, and outputting an optimal array element position arraying scheme; and finally, obtaining a frequency invariance directional diagram with a smaller side lobe based on the SRV constraint of infinite norm. According to the invention, the number of antenna array elements can be effectively reduced, the frequency-invariant wave beam of the minimum side lobe is realized, and the cost of an antenna system is reduced while the performance of the broadband array antenna is ensured.

The present invention discloses a wide microstrip antenna array based antenna system for millimeter wave applications. The microstrip antenna array based antenna system of the present invention includes plurality of patch antennas and each of the patch antennas includes a U-slot of unequal arms. This patch antenna with the U-slot acts as the array element. The array elements are placed in a linear array at a distance of λ / 2 from each other on the antenna substrate to achieve desired scan performance. The microstrip corporate feed network with T-junction power divider is used. The antenna elements are fed by electromagnetic coupling with the feed network. The antenna array with dummy elements on both sides of the linear array together with an extra ground plane is used to achieve improved array performance with high main lobe gain and reduced side lobe.

The invention discloses a large-scale phased array multi-channel partition beam control method and device based on an FPGA and a storage medium. The method comprises the steps that a control instruction of an antenna control unit is acquired; analyzing the control instruction which is verified to be correct, judging an instruction type according to an analysis result, when the instruction type is a beam switching instruction, determining a beam control parameter in the instruction, and calculating a base code of the phased-array antenna according to the beam control parameter; the array elements of the phased-array antenna are divided into a plurality of areas, according to the base codes and the position coordinates of the array elements, the wave control codes of the array elements are calculated in parallel by adopting a multi-channel partitioning method, and the wave control codes are normalized and then written into a beam forming chip in parallel; and after the operation is completed, a corresponding response instruction is sent to the antenna control unit. The method has the advantages of being high in beam switching speed, small in resource consumption and good in universality, an array can form a sparse array in the mode of sending a control instruction, and therefore side lobes are restrained, and power consumption is reduced.

The invention provides a communication perception integrated beamforming method and system for suppressing distance-angle side lobes, and the method comprises the steps: enabling a base station to communicate with a plurality of users under a digital beamforming ISAC architecture, and carrying out the detection of an air target in a self-transmitting and self-receiving mode at the same time; determining a sensing channel model and a communication channel model to obtain a communication receiving signal at each user position and a sensing receiving signal scattered back to the base station from the target; calculating to obtain the SINR of each user; a distance-angle-Doppler three-dimensional perception fuzzy function based on a digital beam forming ISAC architecture is obtained; extracting an expression of an integral sidelobe of a distance-angle dimension; according to the communication index, the sensing index and the integral sidelobe value in the preset distance-angle sidelobe area, a beam forming matrix of the ISAC system is designed in a joint optimization mode; auxiliary variables are introduced to convert the problem of optimizing the beam forming matrix into the problem of optimizing a covariance matrix of the beam forming matrix, and a feasible solution of the joint design problem is obtained.

The invention discloses a satellite beam scanning scheduling method and device and a storage medium. The method belongs to the field of satellite communication, and comprises the following steps: acquiring parameter characteristics of coverage areas of multiple beams of a satellite; inputting the parameter features into a pre-trained neural network model, and determining sub-bands adapted to the plurality of beams through the neural network model; a chromosome vector is initialized, an initial population is constructed, and the chromosome vector is used for indicating the beam position scanned by each beam of the satellite in each beam hopping time slot of the beam hopping period; constructing a fitness function; performing iterative optimization on the initial population according to a genetic algorithm, and determining an optimal chromosome vector; and according to the optimal chromosome vector, determining the beam position scanned by each beam in each beam hopping time slot of the beam hopping period. Therefore, coverage overlapping and sidelobe leakage interference of same-frequency beams are avoided to the maximum extent from the scanning time sequence dimension, and dual targets of sub-band adaptation and interference suppression are synchronously achieved.

The invention discloses an intelligent metasurface-assisted phased array transmitting beam directional diagram accurate control method. An intelligent metasurface RIS is introduced into a phased array transmitting system, and an additional signal propagation path is added for transmitting beam forming by utilizing the characteristic that the RIS can freely regulate and control a reflected signal, so that an additional system degree of freedom is obtained. Specifically, a difference value between a minimum peak side lobe power and a minimum main lobe power of a transmitted beam is taken as a target function, and under phase-only transmission weight constraint, main lobe ripple constraint and RIS constant modulus constraint, an alternating direction penalty method is utilized to carry out joint design on a phase-only transmission weight and RIS phase shift. In the iterative solution of the alternating direction penalty method, the subproblem with the constant modulus constraint is solved by adopting a backtracking projection gradient descent method. The method provided by the invention can generate smaller main lobe ripples and lower peak side lobe level, and has better accurate control performance of a beam directional diagram.

The invention belongs to the technical field of underwater target radiation noise measurement, and particularly relates to a sparse combination array measurement system and method for underwater target radiation noise measurement, a program and a storage medium. A sparse combined array formed by a sound pressure spiral double-cone volume array with a sparse structure and a sound pressure vector nested vertical linear array is designed, a combined array frequency-division testing scheme of a high-frequency volume array and a low-frequency vertical linear array is adopted, a combined measurement method of a sound pressure hydrophone and a vector hydrophone is utilized, a measurement frequency band is extended, and the measurement precision is improved. And effective measurement of the full-band radiation noise of the underwater target is realized. Through a sparse array arrangement structure and an improved constant-beam-width beam forming method, a two-dimensional steady constant-beam-width beam is obtained while the number of array elements is reduced and the array complexity is reduced, and an appropriate main lobe width and a lower side lobe level can be adjusted according to a measured target and a measurement distance. According to the method, the array element redundancy of the measurement array is reduced, and the method can be flexibly applied to various application scenes of underwater radiation noise measurement.

The invention discloses a multi-target anti-interference detection system based on a holographic staring radar, relates to the technical field of holographic staring radars, and constructs a technical architecture consisting of an array calibration module, a beam forming and optimizing module, a self-adaptive filtering module and a self-adaptive control module. Interference between beams is effectively suppressed by adopting a minimum sidelobe beam forming algorithm, dynamic suppression of near-angle strong interference is realized by combining spatial domain-time domain combined filtering, and beam parameters are adaptively optimized by utilizing fusion analysis and a feedback mechanism, so that the multi-target detection precision and the anti-interference capability of the system in a complex urban environment are remarkably improved, and the system has a wide application prospect. The stability and the practicability are relatively high.

The invention discloses a millimeter wave circular polarization ridge gap waveguide antenna. The waveguide antenna comprises a feed waveguide layer, a waveguide gap layer, a grating lobe suppressor, a polarization converter and a radiation cavity layer which are sequentially stacked from bottom to top. The waveguide antenna adopts an interdigital ridge structure, so that electromagnetic wave leakage radiation can be effectively inhibited, the stability of the working mode of the antenna unit is ensured, and the isolation of the antenna in a large-scale array is enhanced; the feed waveguide layer and the waveguide slot layer are spliced to form the interdigital ridge structure, the production and assembly process is simple, the welding process is omitted, and the production cost is reduced; left-hand circular polarization or right-hand circular polarization can be switched on the polarization converter by changing the orientation of the cross-type gap. By feeding from the two ends of the feed waveguide layer, a dual-circular-polarization working mode can also be realized; by adjusting the size of each slot on the waveguide slot layer, the flexibility of grating lobe suppression can be improved, and the side lobe level of the antenna can be reduced. The invention relates to the technical field of antennas.

The invention discloses a high-precision spectral interference signal demodulation method for micro distance measurement. The method comprises the steps of S1, interference spectrum shaping; measuring an interference spectrum and a reference spectrum; selecting a six-item combined cosine window as a primary function of an interference signal to obtain a shaped interference spectrum; s2, performing non-uniform Fourier transform to obtain a frequency spectrum of the target signal; s3, on the basis of a multi-spectral-line interpolation algorithm, interpolation is carried out on the window function to solve a fitting function, and a center frequency k is obtained; and S4, outputting a result. And solving and outputting an optical path difference d. According to the method, a six-item cosine combination window is selected as a primary function of an interference signal, and the problem that the accuracy of signal extraction is influenced by mutual superposition of side lobes and even main lobes of a direct current item and a solved frequency item is solved; an interference spectrum is processed by using a fast non-uniform Fourier transform algorithm, accuracy can still be kept under the conditions that the distance to be measured is increased and sampling is gradually sparse, and the problem of resampling deviation caused by a traditional interpolation method can be solved.

The invention belongs to the technical field of antennas, and particularly relates to a low-sidelobe X-waveband waveguide slot array antenna. The antenna comprises an antenna array plane, the antenna array plane comprises a plurality of sub-array antennas which are arranged in parallel at equal intervals, each sub-array antenna is a waveguide slot array antenna, each waveguide slot array antenna is externally connected with a TR assembly, and the center-to-center distance d1 between every two adjacent waveguide slot antennas is 16mm; according to the technical requirements, horizontal polarization is achieved in the mode that an inclined slot is formed in the narrow side of a rectangular waveguide, finally, the design of the low-sidelobe horizontal polarization waveguide slot traveling wave array antenna is achieved, and the sidelobe level in the antenna working frequency range averagely meets the design target that the sidelobe level of a transmitting pitching face is lower than-12dB, the sidelobe level of a receiving pitching face is lower than-25dB, and the sidelobe level of the receiving pitching face is lower than-25dB. According to the invention, the side lobe level of the azimuth plane is lower than-25dB, the normal transmitting gain is greater than 35dBi (full-band), the receiving gain is greater than 33.5 dBi, and the antenna has the advantages of low side lobe, high gain and narrow beam, and is suitable for being applied to an X-band radar communication system.

The invention discloses a multi-strategy joint improved sparse area array optimization method and system, and the method comprises the steps: calculating the peak side lobe level of each initial array element distribution, and obtaining the current lowest peak side lobe level and the optimal array element distribution corresponding to the lowest peak side lobe level, updating the positions of the array elements according to an ascending stage, a descending stage and a landing stage in the improved dandelion optimization algorithm; starting a Cauchy spiral inverse cumulative distribution variation strategy to vary the positions of the array elements, calculating the target lowest peak side lobe level of the updated array element distribution, and if the value of the target lowest peak side lobe level is greater than the value of the lowest peak side lobe level, replacing the updated array element distribution; and updating the global optimal array element distribution position and the corresponding lowest peak sidelobe level. The efficiency of the algorithm in the aspects of global search and local development is improved, the algorithm is prevented from being caught in local optimum too early, and therefore the solving precision and the convergence speed of the algorithm are improved.

The invention relates to the field of underwater acoustic communication and detection, in particular to a waveform optimization method and system for an underwater acoustic detection and communication integrated system. According to the method, a constant modulus phase is taken as a constraint, a reserved subcarrier phase is taken as an optimization variable, and a multi-objective function for joint optimization of a peak-to-average power ratio and a non-periodic autocorrelation integral sidelobe ratio is constructed; a population is initialized, an objective function is evaluated, and a parent population is obtained through non-dominated sorting and crowding distance calculation; generating filial generations through selection, crossover and variation, combining the filial generations with the parent generations, and updating sorting and crowding distance to maintain population diversity; introducing a local gradient descent refinement mechanism, carrying out gradient iteration adjustment on an optimized individual under a constant modulus phase condition, and adaptively adjusting a crossover probability, a mutation probability and a phase variation scale according to a diversity evaluation result; and outputting a Pareto optimal solution set after the maximum number of iterations is reached, and obtaining an optimized sounding and communication integrated orthogonal frequency division multiplexing signal, so that the underwater communication and detection comprehensive performance can be effectively improved.

The invention discloses an audio data processing method and device and electronic equipment, and relates to the field of audio processing. The method comprises the following steps: acquiring original multichannel audio data through a microphone array; generating a main beam output signal pointing to the target sound source direction and at least one sidelobe suppression output signal; extracting voiceprint feature vectors; comparing the voiceprint feature vector of the current frame with the center vector of the existing voiceprint class cluster to obtain a voiceprint clustering result; if it is determined that the first voiceprint class cluster and the second voiceprint class cluster exist, extracting a first audio frame belonging to the first voiceprint class cluster and a second audio frame belonging to the second voiceprint class cluster, and performing audio reconstruction to obtain a first voice stream and a second voice stream; and carrying out residual noise elimination on the sidelobe suppression output signal to obtain a first isolated audio stream and a second isolated audio stream. By implementing the technical scheme provided by the invention, the audio processing quality is improved.

The embodiment of the invention provides a beam weight generation method, device and equipment, and relates to the technical field of communication, and the method comprises the steps: respectively setting signal snapshots and array manifold vectors of an expected angle and an unexpected angle of a to-be-generated beam; wherein the expected angle is an angle corresponding to a main lobe of a to-be-generated beam, and the unexpected angle comprises an angle corresponding to a side lobe of the to-be-generated beam; generating a cost function according to the set signal snapshot and the array manifold vector; the variable of the cost function is the weight of a to-be-generated beam, and the dependent variable is the sum of a first preset parameter and a second preset parameter; and performing iterative operation on the cost function on the basis of a preset local particle swarm optimization algorithm based on a von Noiemann topological structure so as to obtain a target weight of the to-be-generated beam. According to the embodiment of the invention, the technical problem that the beam directivity and the main lobe power are difficult to consider in the existing weight generation mode of the multi-peak beam can be solved.

The invention discloses a non-cooperative target sidelobe sensing method and system, a medium and equipment, and belongs to the technical field of spectrum sensing. The method comprises the following steps: acquiring a to-be-sensed sidelobe signal emitted by a non-cooperative target; establishing a cooperative sensing problem of to-be-sensed sidelobe signals under different signal-to-noise ratios; inputting the to-be-sensed sidelobe signal into a pre-constructed sensing network model, and outputting a sidelobe sensing result of the non-cooperative target; wherein the processing step of the sensing network model comprises the following steps: according to the cooperative sensing problem, judging a sensing result of a to-be-sensed sidelobe signal at a sensing node; and deciding a sidelobe sensing result of the non-cooperative target according to a sensing result of the to-be-sensed sidelobe signal at the sensing node. According to the method, the cooperative sensing problem of the to-be-sensed sidelobe signals under different signal-to-noise ratios is established, and the sensing result is judged and decided through the cooperative sensing problem, so that the accuracy of detecting the non-cooperative sidelobe signals is greatly improved.

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 relates to the technical field of array antennas, in particular to a sparse linear array beam forming method and system with unit rotation and mutual coupling considered. Array elements are obtained, Euler angle derivation is carried out on rotation of the array elements around the z axis, and a radiation electric field after rotation is obtained; setting a beam forming target according to the electric field of the radiation field; according to a beam forming target, optimizing the position, the rotation angle and the excitation phase of an array element by adopting a random optimization algorithm, and generating an initial beam scheme; an active directional diagram is extracted from the initial beam scheme according to full-wave simulation, the active directional diagram is combined with a CAL-SAPSO algorithm to optimize the array element position, the rotation angle and the excitation phase, and a final array element directional diagram is generated; according to the invention, by introducing array element rotation and considering a mutual coupling effect, efficient beamforming of the sparse wiring array is realized, the radiation characteristic of the antenna array can be adjusted more finely, the peak side lobe level and the cross polarization level are effectively reduced, and the overall performance of the system is improved.

Various embodiments relate to a radar system, including: a transmitter; a transmit antenna connected to the transmitter, wherein the transmit antenna is a circular polarized antenna; a receiver; a receive antenna connected to the receiver, wherein the receive antenna is a dual polarization antenna having a main lobe and ambiguity sidelobes; wherein the radar system is configured to: transmit a first and second radar signal with first and second circular polarizations in first and second modes; receive reflected first and second radar signals; process the received first and second radar signals to detect a target and to produce first and second mode target powers; comparing the first mode target power to the second mode target power to determine which lobe of the antenna in which the target is located.

The invention relates to an ultra-low side lobe row feed array. The main types of current engineering include a traveling wave waveguide array and passive row feed with unequal power division feed. Due to the existence of an azimuth frequency scanning angle, zenith scanning blind spots exist, the larger the frequency deflection angle is, the larger the scanning dome blind area is, and azimuth beams are fixed, so that multiple beams cannot be formed; although the beam points to the normal direction, the defect of large loss exists. Aiming at the defects in the prior art, the invention provides the ultra-low side lobe dual-polarization active row feed array with variable unit number and unequal power division, a form based on an unequal unit active subarray is adopted, dual-polarization active row feed is realized, and the ultra-low side lobe dual-polarization active row feed array has the characteristics of ultra-low side lobe, low cost and low loss.

The invention discloses a portable satellite communication station signal optimization method and system, relates to the field of wireless communication, and is used for synchronously realizing dynamic adaptive management of multiple scattering paths. The method comprises the following steps: generating an earth surface image through multi-modal detection data, and carrying out layered calibration on scattering intensity; identifying a high-reflection sub-region according to the surface image and the layered calibration information thereof, and performing unified management on high-reflection and weak echo paths; based on the gain, interference and angle information of the multiple scattering paths, performing sub-array division on the antenna array according to priorities; phase stepping correction is carried out on the antenna units of the sub-arrays, and emission excitation is combined in adjacent path coverage areas; through a dynamic power scheduling and beam forming algorithm, the direction gain of each sub-array is optimized and sidelobe leakage is controlled. According to the invention, synchronous management of high reflection and weak echo paths can be realized, and the dynamic adaptability to scattering scenes is improved.

The invention discloses an SAR (Synthetic Aperture Radar) active interference identification method under a low interference-to-signal ratio condition, a system storage device and electronic equipment. The method comprises the following steps: carrying out normalization processing on a time domain image of interference, and weakening a sidelobe influence through power law transformation after carrying out normalization processing on a time-frequency domain image; taking the preprocessed time-domain image and the time-frequency-domain image as dual-channel input of the network, and extracting multi-scale features by using a diversified branch block and a channel attention mechanism; fusing the extracted time domain features and the extracted time-frequency domain features through a weighted fusion strategy, carrying out dynamic weight distribution on the features of the time domain and the time-frequency domain, and introducing variance parameters of signals and interference to carry out feature optimization under a low interference-to-signal ratio; and inputting the fused feature sequence into a Transform, calculating the attention weight of any position through a Query-Key-Value matrix, capturing a long-distance dependency relationship, and enhancing global feature representation. According to the method, the SAR active interference pattern under the low interference-to-signal ratio can be identified with high precision, and powerful support is provided for a subsequent anti-interference strategy.

The invention discloses a parallel simulation method for guided wave focusing imaging of a piezoelectric array of a composite structure, belongs to the technical field of nondestructive testing, and aims at solving the problems that the sound field control precision of a current multi-array-element piezoelectric structure in a composite material plate is insufficient, and a traditional finite element method is large in calculation time consumption, low in convergence speed and high in reliability in the guided wave propagation simulation process. In order to solve the problem that effective convergence cannot be realized under the excitation condition of a high-frequency multi-channel array and even under the excitation condition of a high-frequency multi-channel array, the invention provides an efficient guided wave focusing simulation strategy combining spectral element high-order precision and GPU parallel computing, and the method comprises the following steps: establishing a system control equation considering a piezoelectric-structure coupling effect on the basis of a delay superposition principle; energy focusing and sidelobe suppression of a guided wave signal in a specific direction are realized by adjusting spatial arrangement and excitation time sequence of a piezoelectric array sensor, Gauss-Labatto-Legendre integral nodes are introduced to construct a high-order spectral element unit, unit-level parallel solution is realized under a CUDA architecture, and dynamic simulation capability and overall calculation efficiency of focusing field distribution are remarkably improved.

The invention discloses a double-ridge waveguide slot array antenna which comprises a radiation structure, a double-ridge waveguide feed structure and a switching structure. The radiation structure is formed by symmetrically and collinearly arranging a plurality of slots and is used for radiating electromagnetic waves with indexes such as specific beam width and sidelobe level. The double-ridge waveguide feed structure comprises feed double-ridge waveguides, double-ridge waveguide power dividers and radiation snakelike double-ridge waveguides, the feed double-ridge waveguides are connected with the switching structure and the power dividers, the double-ridge waveguide power dividers distribute signals to the radiation snakelike double-ridge waveguides according to a specific power division ratio and phase difference, and radiation slots are formed in the upper portions of the radiation snakelike double-ridge waveguides. And the switching structure is used for switching the double-ridge waveguide to transmission lines such as a rectangular waveguide and a microstrip line, and is finally connected with a test port or a chip and the like. The antenna provided by the invention has the characteristics of wide frequency band, high gain, stable directional diagram and extremely low cross polarization. The invention further provides vehicle-mounted millimeter wave radar equipment.

The invention relates to the technical field of acoustic imaging, and discloses an acoustic imaging system of a concentric-circle nested microphone array, which comprises a central microphone and the concentric-circle nested microphone array. The concentric nested microphone arrays are concentrically arranged by taking the central microphone as the center, a plurality of microphones are distributed on each layer of circular microphone array according to a nested array rule, and the distance between each layer of adjacent microphone arrays is d. By adopting a unique circular nested microphone array structure, the position information of a sound source can be accurately captured through the cooperative work of multiple layers of microphone arrays. A plurality of microphones are distributed in each layer of microphone array in a circular nested array, a multi-dimensional sound acquisition network is formed by combining a central microphone, and meanwhile, the signal processing module gradually extracts and reconstructs sound source information in a sound field by utilizing a CLEAN-SC algorithm and through iterative decomposition and removal of strongest components in sound source signals, so that a sidelobe interference image is effectively inhibited, and the sound quality is improved. Therefore, a high-resolution sound power distribution diagram is obtained, and acoustic imaging is realized.