41results about How to "Suitable for engineering realization" patented technology

The invention relates to a method for detecting coherent integration of a radar target in the field of radar technology. The method comprises the following steps of: determining the pulse count of the coherent integration according to motion characteristics and detection indexes of the radar target; determining the search speed channel interval and the number of Doppler filters, and searching the distance interval and the distance unit number; determining vectors of the Doppler filters; obtaining a coherent integration result along with a straight line determined by the search speed and the search distance; traversing all the search speed and the search distance to acquire a parameter transformation data matrix; and performing constant false alarm detection on the parameter transformation data matrix to acquire trace point information of the radar target. The method overcomes the span length unit walking effect on a constant speed target during the time period of the coherent integration, selects data along with the straight line without shifting and interpolating operations, needs no repetition frequency staggering to acquire target non-fuzzy speed estimation, is suitable for low repetition frequency long-range radar application, and has high speed testing resolution ratio and accuracy.

The invention discloses a spaceborne SAR echo correction and pulse compression method based on reference signals. The method includes noise and interference suppression of the reference signals and echo signals, amplitude correction and phase compensation factor acquisition from the reference signals, and echo signals amplitude correction and phase compensation. By means of spaceborne SAR echo correction and compensation on the basis of the reference signals, influence on the subsequent imaging processing step and image focusing effect due to signal distortion errors caused by system nonideal phase amplitude characteristics can be reduced, and the harsh phase amplitude characteristic index parameter requirements on a signal source and other single machines by a high-resolution spaceborne SAR system can be alleviated to the certain extent; the compensation and correction method is simple and easy to implement, and the computing efficiency is improved greatly.

The invention relates to a radar interference inhibition method and particularly relates to a radar dense false target interference inhibition method. The radar dens false target interference inhibition method comprises steps of importing orientation video data of an object to be detected which is scanned by the radar, calculating the orientation noise power of the object to be detected to obtain a noise evaluation value, recognizing interference, perceiving the interference environment and positioning the interference source, 3 identifying the interference, performing signal statistic analysis on the radar scanning video data in the interference field, determining whether the dense false object interference exists, 4 inhibiting the interference, adopting the frequency domain filtering technology to perform interference resistance processing on the dense false object interference data, 5 detecting an object, adopting CFAR to process the object data to be detected which has gone through anti-interference inhibition, and 6 performing tracing and track correlation on the object to be detected to finish the tracking of the object. The radar dense false target interference inhibition method can guarantee the normal operation of the radar under the interference of the dense false objects and identifies whether the false objects exist through the characteristic analysis.

The invention relates to a roadbed soil dynamic rebound modulus predicting system and method. The system comprises a soil sampler, an electronic balance, a drying box, a volume-weight tester, a liquid-plastic limit combined tester, a triaxial experiment instrument and a computer. The liquid-plastic limit combined tester comprises a support, an electromagnet, a cone penetrator with a scaleplate, a sample cup, a control switch and a lifting base, wherein the electromagnet is installed in an upper frame of the support, the cone penetrator with the scaleplate is adsorbed to the portion below the electromagnet, the lifting base is installed in a lower frame of the support, the sample cup is located on the lifting base, and the control switch is located on the side face of the lower frame of the support. Compared with the prior art, the roadbed soil dynamic rebound modulus predicting system and method are based on a radial basis function neural network, selected input indexes have defined meanings, a predicting model is high in automation degree, and the roadbed soil dynamic rebound modulus predicting system has the advantages of being high in calculation speed and accuracy, and suitable for engineering realization.

The invention discloses a geo-synchronous orbit synthetic aperture radar (GEO SAR) frequency modulation changeable standard (CS) imaging method under a curve track model. The method comprises the following steps of: establishing an oblique-distance and high-order expression under the GEO SAR curve track model; deducing a two-dimensional spectrum expression of an echo signal; performing triple Taylor expansion of a distance frequency on the two-dimensional spectrum expression; compensating a triple phase item of the distance frequency in a two-dimensional frequency domain; calculating a distance migration curve in a distance-Doppler domain and multiplying the distance migration curve by a constructed CS phase function; deducing a distance compensation function to finish distance focusing and distance migration correction; and performing direction compression and direction residual phase correction to finish direction focusing. By the method, the spatial-variant properties of the distance migration can be compensated, a wider imaging plotting bandwidth can be obtained and full-aperture high-resolution imaging can be realized. All types of operation in the method are finished throughfast Fourier transform and phase dot product; furthermore, the efficiency is higher and the method is suitable for engineering implementation.

The invention discloses a method for identifying permanent magnet flux and quadrature axis inductance of a permanent magnet synchronous motor. The method comprises the steps as follows: designing a filter based on an identification algorithm and calculating identification parameters. The accuracy of the permanent magnet flux and quadrature axis inductance parameters directly influences the control performance of a vector control system of the permanent magnet synchronous motor. But the existence of a saturation effect and the like enables the motor parameters to be non-linearly changed. Therefore, a change curve of the motor parameters is necessarily measured or identified on line. The invention discloses the simple and easy method for identifying the permanent magnet flux and the quadrature axis inductance, and the control performance of the system is improved on the basadopts not increasing the system cost.

The invention discloses a two dimentional attitude control system of a synthetic aperture radar satellite, which includes a satellite position analysis module, a satellite position analysis module and an expected attitude determination module. The two dimentional attitude control system is applied in the situation that the synthetic aperture radar satellite runs on an elliptic orbit, and echoed signal doppler center frequency can be controlled to be zero by applying yaw-pitch-two-dimensional attitude control technology, thus effectively weakening the degree of coupling between distance vector and direction vector and lowering the difficulty and operand of imaging process.

The invention discloses an equivalence model based discrete sliding mode control method for a hypersonic velocity aircraft and belongs to the field of aircraft control. The method is used for solving the technical problem that discrete adaptive control of existing hypersonic velocity aircrafts is difficult to implement in engineering. The method comprises the steps of firstly, converting a height subsystem model of the hypersonic velocity aircraft into a strict-feedback form, further establishing a discrete strict-feedback form of an original system through an Euler method, considering the causal sequence of the system, establishing an equivalence model of the original system, using the equivalence model to analyze historical information of the uncertainty of the system, using the historical information for design of a sliding mode controller, and designing the controller according to backstepping method strategies through error feedback by using a nominal system. According to the method, characteristics of computer control are combined, non-causal problems are effectively avoided through the controller which is obtained through model conversion, and the height and the velocity of the hypersonic velocity aircraft can be tracked without adaptive estimation strategies which are complex in design.

The invention provides an error resilient coding method for high-efficiency data reading. The error resilient coding method comprises a method for coding and constructing IZSHC (Intersecting Zigzag Sets Hierarchical Codes) and a method for reading failure data under IZSHC, wherein the method for coding and constructing IZSHC refers to implementing redundant processing on to-be-read original data, i.e. coding an original document to generate redundant data blocks; the redundant data blocks are divided into original data blocks and checkout data blocks; the method for reading the failure data under IZSHC refers to reading decoding the failure data for recovery by utilizing the redundant data blocks when reading failure occurs to the original data blocks. According to the error resilient coding method, based on the IZSHC, the data reading performance in the case of node failure can be obviously improved.

The invention discloses a non-uniform array design and direction of arrival (DOA) estimation method and mainly aims at solving the problems that arrangement is inflexible and computation complexity isrelatively high in the prior art. A realization process of the method comprises the following steps: according to maximum freedom degree of a nested array, determining head and tail position coefficients of a non-uniform array; calculating position coefficients of all the virtual array element positions meeting the non-uniform array and contained in a differential synthetic matrix; according to the position coefficients, finally obtaining positions of array elements of the non-uniform array; according to received data, calculating a data covariance matrix and vectorizing, so that received data r of a virtual differential synthetic array is obtained; performing redundancy elimination on the r and sorting to obtain received data of a virtual array, and then obtaining a non-singular matrix vof the virtual array; constructing a linear operator, and obtaining a signal subspace by estimating the linear operator; and constructing a selection matrix to obtain a rotation matrix, and finally estimating a direction of arrival by virtue of the rotation matrix. The method disclosed by the invention has the advantages that array configuration is flexible, characteristic decomposition does notneed to be performed on the data covariance matrix and spectral peak search does not need to be performed on the whole airspace angle under the same conditions.

The invention belongs to the technical field of radar imaging, and discloses a curvilinear track SAR squint imaging method based on an improved slant distance model. The curvilinear track SAR squint imaging method based on the improved slant distance model comprises the specific steps that an equivalent slant distance model is established; a two-dimensional spectrum is derived; the distance walking momentum is calculated and is transformed to the distance frequency domain to complete the distance walking correction in the distance direction; an echo signal in the distance frequency domain is subjected to the fourier transformation in the azimuth direction, and a two-dimensional spectrum of the echo signal is obtained; distance compression, secondary distance compression and distance bending correction are carried out, and the echo signal is subjected to inverse fourier transformation in the distance direction; and an azimuth frequency domain signal is subjected to azimuth compression and inverse fourier transformation in the azimuth direction, and imaging results are obtained. According to the curvilinear track SAR squint imaging method based on the improved slant distance model, on the basis of motion characteristics of a curvilinear track platform, the equation of motion of the curvilinear track platform is subjected to high-order approximation, a four-order equivalent slantdistance model expression is established, based on the slant distance model, the analytical solution of the two-dimensional spectrum of the curvilinear track platform is derived, the conciseness and the high precision of a frequency spectrum is ensured, and full-aperture high-resolution imaging can be achieved.

The invention provides a finite field multiplier based on an RS (reed-solomon) code. The finite field multiplier based on the RS code is composed of two partial operations, firstly a common polynomial multiplication is carried out, and the obtained result is a polynomial with the highest order of 2m-2, wherein m is bit width of two finite field multipliers; and secondly, modular operation is carried out on the primitive polynomial p(x) by adopting the product polynomial, and the obtained remainder coefficient is namely final result of a finite field multiplication. The invention innovatively provides a two-step implementation method of the finite field multiplier. A modulus calculating circuit is composed of sublayers of the same structures, structure is regular, expansion is easy, engineering realization is applicable, the finite field multiplier with any bit width can be realized by regulating sublayers in a modulus obtaining circuit framework, and the finite field multiplier is especially applicable to error control code field such as application of the RS code and can meet urgent demand of easy implementation of VLSI (very large scale integration) design in a communication system.

The invention provides a device for estimating and compensating sampling clock offset of a handset television terminal, comprising the following modules of an over-sampling interpolation filter module, an FFT / descrambling module, a continuous pilot extraction module, a sampling clock offset estimation module and a sampling clock offset control module, wherein the over-sampling interpolation filter module completes the over-sampling interpolation, filtering and desampling extraction of the input data and adjusts the sampling clock offset according to the final sampling clock offset estimation result; the FFT / descrambling module carries out FFT operation and descrambling treatment; the continuous pilot extraction module extracts continuous pilot sub-carrier data from the descrambled data; the sampling block offset estimation module completes the estimation of the sampling clock offset; and the sampling clock offset control module obtains the final sampling clock offset estimation result according to the provided estimation results and supplies the results to the over-sampling interpolation filter module. Simultaneously, the invention provides a method for estimating and compensating sampling clock offset of a handset television terminal. The device and the method can simplify the treatment and ensure receiving performance.

The invention relates to a signal processing architecture transplanting method based on a ZYNQ platform, which aims at an original signal processing architecture of a 2DSP + FPGA, and comprises the following steps: S1, summarizing interface interaction between two DSPs, and summarizing interface interaction between the two DSPs and the FPGA respectively; s2, respectively transplanting the codes ofthe two DSPs into the dual cores of the PS end of the ZYNQ platform, and transplanting the codes of the FPGA to the PL end of the ZYNQ platform; s3, completing interface interaction between the two DSPs by using a shared memory between the PS end dual cores of the ZYNQ platform; s4, utilizing a GP bus between the PS end and the PL end of the ZYNQ platform to complete interface interaction betweenthe two DSPs and the FPGA; and S5, completing hardware acceleration of the Fourier transform module by utilizing the direct storage accessor of the PL end of the ZYNQ platform and the IP core of theFourier transform module. Equivalent substitution of a signal processing architecture is realized, and the problem of platform transplantation is solved; and the method is high in universality and suitable for engineering realization.

The invention provides an SAR moving ship target detection method and device, and relates to the technical field of synthetic aperture radar image target detection. The method comprises the following steps: acquiring a single-vision complex image and an amplitude image data set of the synthetic aperture radar; performing data annotation on the amplitude image data set, and randomly selecting a training set from the amplitude image data set; performing feature extraction on the training set by using a deep learning model to obtain feature maps of multiple scales and spatial transformation information; estimating a Doppler center frequency shift matrix of the single-vision complex image according to the spatial transformation information; performing feature fusion on the Doppler center frequency shift matrix and the feature maps of each scale to obtain a fusion feature map with target motion information; and sending the fused feature map into a target detection module, and outputting a detection result of the moving ship target. According to the method, Doppler center frequency shift features are combined with a deep learning model, Doppler domain fusion prediction is adopted, and the detection effect of a moving ship target is improved.

The invention discloses an interference characteristic extraction method based on projection transformation. The interference characteristic extraction method comprises following steps of: 1, calculating radar parameters; 2, interference sensing: sensing interference environment and judging whether interference exists or not; 3, interference positioning: calculating an interference orientation center and the interference strength and positioning an interference source; 4, projection transformation: selecting interference data of an interference strength concentration region, and adopting a projection transformation method to calculate a projection characteristic matrix; 5, interference slope characteristic extraction: carrying out characteristic counting on the projection characteristic matrix, analyzing characteristic distribution in the orientation, and calculating interference slope characteristics; and 6, feeding back the interference slope characteristics to a radar system.

This invention relates to a method for reducing peak-to-average ratio of multi-carrier modulation system including: cutting in special data on a vacancy sub-carrier of the modulation system, making an inquiry list to overlap the original data and the corresponding data in the enquiry list in linearity and the peak-to -average ratio output by the IFFT is the smallest, enquiring said list to get assistant data to be combined with effective data for IFFT output.

A modeling method of cement concrete road surface humidity field considering health maintenance effect comprises the following steps: 1) establishing a control equation of water migration by using the second Fick law, wherein the function expression of the control equation is: (A formula is provided); 2) determining definite conditions for the control equation of water migration; 3) using concrete drying test data under health maintenance conditions and SPSA algorithm to demarcate parameters involved in the control equation of water migration; 4) using numerical method of user-defined format and the definite conditions as well as the demarcated parameters to solve the control equation of water migration; the solution is a humidity distribution curve, i.e., the cement concrete road surface humidity field considering the health maintenance effect. The modeling method of cement concrete road surface humidity field considering health maintenance effect overcomes the defect of the prior art that the effect of humidity gradient is not considered in cement concrete road surface stress analysis; provided is a modeling method of cement concrete road surface humidity field considering health maintenance effect which provides parameters for precise design of cement concrete road surfaces of highway and city roads.

The invention discloses a method for reducing the concentration of agglomerate fog, and the method can effectively reduce the concentration of agglomerate fog. The method comprises the following steps: S10, mixing compressed gas and a defogging agent to form a mixed fluid; S20, spraying the mixed fluid to the agglomerate fog, wherein the mixed fluid moves in a vortex ring form to form a directional gas ring so as to convey the defogging agent; and S30, reducing the concentration of agglomerate fog and improving the visibility by using the demisting agent in the flowing gas ring.

The embodiment of the invention provides a network capacity improving method and device based on an electromagnetic map. The method comprises the steps that the position of each terminal in all terminals in the dense network is acquired, the dense network comprises a plurality of virtual cells, and each virtual cell comprises a terminal and a plurality of base stations with the terminal as the center; slow-varying channel state information corresponding to each terminal is obtained according to the position of each terminal and a preset electromagnetic map; the electromagnetic map records a preset corresponding relationship between different terminal positions obtained in advance and slow-varying channel state information; and a sending signal matrix of the virtual cell where each terminalis located is correspondingly obtained according to the slow-varying channel state information corresponding to each terminal. According to the embodiment of the invention, the complexity of networkcapacity improvement is reduced.