最新刊期
卷 36 ， 期 12 ， 2008
- 摘要：For rotary target,the method for extracting micro-motion feature by using the length of range profile is studied.Firstly,the characteristic of range profile for rotary target is analyzed.The length of range profile can be separated into two parts.One is the radial length of the target,and the other is the illusive length which is produced by rotation.Then,while target is rotating with a constant angular velocity,the length of range profile obeys the absolute value of sinusoid.The radius and the angular velocity can be estimated by using this variety of length.Finally,the results of feature extraction by utilizing the measured data practically in field are shown in figures,which validate the ideas.关键词：rotary target;micro-motion;range profile;feature extraction2|1080|9更新时间：2025-07-16
- 摘要：In recent years,a number of direction-finding algorithms for noncircular signals are proposed.The asymptotic performance and Cramer-Rao Bound (CRB) have been analyzed in the literatures.However,the robustness of these algorithms with modeling errors is out of range of the published papers.In this paper,the MUSIC algorithm for noncircular signals is introduced.The closed-form expression of mean square error is obtained from the first-order perturbation expansion of the spatial spectrum function.The simulation results validate our analysis.The robustness to the angular separation and the noncircularity phase with modeling errors is analyzed by virtue of the analytical results.关键词：array signal processing;direction finding;modeling errors;noncircular signals;MUSIC (Multiple Signal Classification)2|934|4更新时间：2025-07-16
- 摘要：Signal acquisition is the first work of signal processing in Global Positioning System receiver.However,it is difficult to get the accuracy and fast acquisition of the GPS signal by traditional methods when the signal is very weak.The paper presented a new method which applies the technology of acquisition of P(Y) code in the acquisition of C/A code,and gives resolutions account for the problems brought from the data spanning multiple data bits.The simulation results show that,signal which carrier noise ratio is low to 15dB-Hz could be well acquired by the new method,with fast acquisition speed and high sensitivity.关键词：global positioning system (GPS);double block zero padding (DBZP);weak signal processing;fast acquisition2|1142|5更新时间：2025-07-16
- 摘要：In ballistic missile defense,the situation of unresolved targets is of great threaten to the tracking,identification and guidance of ground based radars,and some special efforts must be adopted to deal with it,among which the detection of the presence of unresolved targets is the precondition and basis of all the others.In this paper,the range glint is analyzed in theory through the model of sample ratio established,and then its physical essence is also expatiated using echo spectrum aberration.Base on those above,a general likelihood ratio test is developed to detect the presence of unresolved targets,which uses the information of additional range measurement error introduced by range glint.Finally,the Monte Carlo simulation result identifies the validity of the models.关键词：adjacent range cell samples;unresolved targets;sample ratio;range glint;general likelihood ratio2|1143|4更新时间：2025-07-16
- 摘要：A robot is designed as the special mobile node of WSN.The design can realize the dynamic deployment of nodes and enlarge the monitoring range of WSN.The coordinate system,which denotes the mobile robot’s state and navigation space,is set up based on the RSSI potential field.And it can decrease the model error while RSSI value is converted to distance.The distributed navigation system consists of some nodes which are in one hop communicating region of robot.Each beacon node can detect the distance which is quantized by RSSI value and calculate the control outputs.Then the fuzzy logic control centre will collect the control outputs from each beacon node and calculate the final outputs for mobile robot based on data fusion.Most of calculations are implemented by each static node,it can effectively reduce the robot complicated design and the hardware cost.The effectively of the navigation system based on WSN are fully proved by the simulation and the experimental results.关键词：wireless sensor network;mobile robot;autonomous navigation;RSSI4|1127|1更新时间：2025-07-16
- 摘要：Focusing on the problem of tracking moving targets in image sequences with complex background,a particle-filter tracking algorithm based on dynamic salient feature of targets is proposed.Using for reference the research results of visual attention of psychology,the algorithm fuses the gray-level and the detail and motion of the targets to form a robust dynamic salient feature as the state vector of the particle filter.The salient feature of the targets in the algorithm sources from the bottom characteristics of the targets,so the algorithm is robust.What’s more,the particle filter could solve non-linear and non-Gaussian state estimation.In a word,the algorithm could deal with the trace management of the multi-targets tracking,and cope with appearing and disappearing and combining and dividing of the targets,and partial occlusions then recovering the tracks after temporary loss.The experimental results show that the new algorithm could accomplish the multi-targets tracking in complex image sequences.关键词：salience;target feature;particle-filtering;image tracking2|1812|13更新时间：2025-07-16
- 摘要：For any odd prime p,we give a lemma which is determined when 2 is a cubic residue modulo p. Using it,we define the notion of six cubic-residue codes over F2.We discuss the relations between six codes,and study the length of cubic-residue codes, character of weight and the bound of the minimum Hamming distance.We finally give the generator polynomials of dual codes, and the generating idempotents of cubic-residue code when choose the appropriate primitive p root of unity.关键词：cubic residue codes;generating idempotenes;dual codes2|955|1更新时间：2025-07-16
- 摘要：The mean SNR resolution threshold is a kind of measurement of resolution performance of the eigenstructure algorithms.The formula of the mean SNR resolution threshold of MUSIC algorithm which includes the correlation of two signal sources is deduced.Simulation results show that the positive correlation may reduce the resolution performance of MUSIC algorithm,and that under some condition the negative correlation may improve the resolution performance.The rule of the effect change of correlation on the resolution performance is discussed when some parameters such as the power difference,direction cut angle,the number of array elements and the number of sampling snapshots are changed.关键词：MUSIC algorithm;resolution performance;the mean SNR resolving threshold;correlation2|909|3更新时间：2025-07-16
- 摘要：A new method based on joint pixel interferograms is proposed for three-channel ground moving target indication (GMTI).Firstly,a joint probability statistical model is established using the statistical properties analysis of multilook SAR interferograms after joint pixel processing.Then the false and leak alarms are analyzed.Meanwhile,considering the velocity ambiguity in the range of minimum detectable velocity (MDV),an energy center method is presented to resolve ambiguity.Lastly,the interferometric magnitude and unambiguous phase are jointed to detect moving targets.The validity of new detection method is demonstrated by the results from real data.关键词：ground moving target indication (GMTI);statistics of SAR interferograms;joint pixel;minimum detectable velocity (MDV);velocity ambiguity2|976|3更新时间：2025-07-16
- 摘要：A new effective PFA (Polar Format Algorithm) imaging algorithm for spotlight bistatic SAR of general geometry configuration is presented based on signal model analysis for bistatic SAR.Non-linear interpolation and sampling are adopted during converting polar coordinate to cartesian coordinate according to the characteristics of space frequency samples in raw data domain.The algorithm preserve the character of conventional PFA of separating 2D interpolation to two 1D interpolations,and processing flow,efficiency and performance of the new algorithm are as same as conventional PFA for mono-static spotlight SAR.Lastly,the algorithm is validated through point target simulations.关键词：bistatic;synthetic aperture radar;imaging algorithm2|1206|7更新时间：2025-07-16
- 摘要：When the influence of noise,interpolation and image modality is considered,the image registration method based on mutual information or normalized mutual information may cause local extrema,small convergence area,and even inaccurate registration.According to a simple Schur concave function and the definition of Jensen-Schur measure,generalized divergence measure and f information measure,six new measures were constructed.The Schur function with special concave characteristics can filter the small probability distribution caused by noise,interpolation and so on.The characters of six new measures,mutual information and normalized mutual information are analyzed and compared by applying them to rigid registration.The results of tests show that Jensen-Schur-beta and D-beta measures outperform other measures in convergence performance and noise immunity,and they are time saving in comparison with mutual information and normalized mutual information measures.关键词：image registration;Schur concave function;Jensen-Schur measure;mutual information2|1284|1更新时间：2025-07-16
- 摘要：Hierarchical Mobile IP (HMIP) is able to reduce signaling cost for location management in mobile IP (MIP) networks.This paper focuses on paging-supported HMIPv6.Sequential paging schemes under limited paging delay are studied.In addition,a genetic algorithm (GA) based sequential paging scheme (GABSP) is proposed,in which all the subnets in a paging area are partitioned into groups by a GA making use of location probabilities of MNs,and then,each group is paged in one paging step.The GABSP can achieve the optimal or near-optimal signaling cost.Moreover,the signaling costs of HMIPv6,the HMIPv6 with single-step paging,and the GABSP are compared,and besides,the prerequisite conditions for single or sequential paging to reduce signaling cost are given.Further,numeric results show that the GABSP occupies the lowest signaling cost.关键词：Mobile IP networks;IP paging;Sequential paging;genetic algorithms2|824|2更新时间：2025-07-16
- 摘要：This paper presents a method of formalized answer extraction based on pattern learning.Our method extracts answers directly by matching the question patterns and the answer patterns automatically,which is different from the other traditional feature-based ones.The method gains formalized patterns automatically by using a machine learning strategy.Therefore,huge work load and low coverage of manually methods are avoided.Creatively,we apply logistic regression to estimate the confidence of the learned patterns.The contrast experiments give our method encouraging results,and it achieves fair and objective test in TREC QA track,the result of which shows that the method is a supplementary to the traditional feature based answer-extracting approaches.关键词：pattern learning;question answering system;answer extraction;confidence;logistic regression2|1099|2更新时间：2025-07-16
- 摘要：Firstly,high precision denotation model of satellite orbit dynamics based on physics parameter model and mathematics model which associates sparse parameter representation with time sequence analysis,nonlinear semi-parametric combined observation model based on system error parameters modeling and non-parametric component denotation of model error,and combined orbit determination(COD) parameterized fusion model are established aiming at multi-satellite high precision COD based on bi-satellite positioning system and low earth orbit(LEO).Then parameters estimation algorithms of the former two kinds of models and the combined estimation algorithm of parameterized fusion model are designed.Theoretic analysis and simulated computation results show that the high precision denotation method of sparse parameters model and the optimized modeling method of observation model considering model error can improve modeling precision,and combined estimation algorithm of parameterized fusion model can synchronously ameliorate orbit determination precision ulteriorly.关键词：combined orbit determination;parameterized fusion model;sparse parameter model;nonlinear semi-parametric combined estimation algorithm2|1291|1更新时间：2025-07-16
- 摘要：The characteristics and the principle of Multiple Carrier Frequency MIMO radar system are systemic introduced and the Frequency Modulated Continuous Wave (FMCW) signal and the return signal are analyzed.Then the processing of FMCW when the target is still or moving are detailed discussed as well as some key problem,e.g.the design of Channel Separation Filter (CSF),the range resolution analysis,the precision analysis of velocity compensation and the decision of coherent integration number etc.Based on the characteristics of multiple carrier frequency,the method to employ the IFFT to coherently synthesize pulse is proposed to obtain High Range Resolution (HRR) and a scheme is put forward to solve the coupling of range and velocity when the target is moving and the simulation result shows that it is practical.关键词：multiple carrier frequency FMCW;MIMO radar;synthetic impulse and aperture radar (SIAR);high range resolution2|1354|7更新时间：2025-07-16
- 摘要：This paper presented a generalized algorithm of n-level space vector PWM suitable for hardware implementation.The optimized algorithm was proposed based on the geometrical symmetry of the n-level space vector diagram,which can be split into six sectors with same shape.Through corresponding relationships between sectors,the algorithm carried out all the computation effort of space vector PWM in one specific sector.Compared with the conventional algorithm,the proposed algorithm reduced the computation amount to one sixth of the conventional one,which indicates the proposed one is more suitable to hardware implementation.For flexibility and versatility,some key design considerations were given in hardware implementation.Finally,two design examples- two-level SVPWM IP core and three-level SVPWM IP core were demonstrated to verify the correctness and validity of the proposed algorithm.关键词：space vector pulse width modulation;multi-level;field programmable gate array;intellectual property2|908|0更新时间：2025-07-16
- 摘要：To enhance the quality for vehicle tracking,a robust H∞ filter algorithm under road situation is proposed in this paper.It notices that the running vehicles are constrained by the road network.Using the road network as filtering constraint condition,a dynamical system model with road constraint is built and the corresponding robust H∞ filtering equation is derived.The simulation results show that,the proposed algorithm has more tracking accuracy and better filtering performance than unconstrained H∞ filter and Kalman filter algorithm.关键词：vehicle tracking;road constraint;H∞ filter;robustness2|1017|0更新时间：2025-07-16
- 摘要：The optimal baseline of polarimetric interferometric synthetic aperture radar(POLinSAR)is analyzed based on the random volume over ground(RVoG)model in the application of estimating parameters of the volume scatterers.Based on the basic concepts of baseline decorrelation,RVoG model and phase tube,the existence of POLinSAR optimal baseline is proved.Then the definition of POLinSAR optimal baseline is given and the method for calculating its value is derived.The differences between InSAR optimal baseline and POLinSAR optimal baseline are also presented.Finally,by the experimental simulation,the optimal baseline is validated and the effects of various parameters on the choice of optimal baseline are discussed,which include radar system parameters,imaging geometry parameters and volume scatterer parameters.关键词：synthetic aperture radar;polarimetric interferometry;optimal baseline;RVoG;phase tube2|722|1更新时间：2025-07-16
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A Constrained Multi-sample Texture Synthesis Algorithm Based on Random Expanding of Circular Patches
摘要：This paper uses random expanding of circular patches to avoid the zigzag problem of current scan line multi-sample synthesis algorithm.Gaussian distribution is introduced to constrain the texture distribution ratio,and Poisson image editing is used to smooth the overlapped area of different textures.We also modify the match function to take the structural features into account.The experiment shows this new method can control the texture distribution while keeping the continuity of visual concept and texture structure.关键词：multi-sample synthesis;allocation ratio constraining;Gaussian distribution2|1198|1更新时间：2025-07-16 - 摘要：Based on the concept of aperture synthesis sparse antenna,the imaging radar on the stratosphere airship for the earth observation is investigated.The multiple phase centre aperture synthesis method in time division mode is proposed to eliminate the high side lobes of sparse array.Using simulated annealing algorithm to optimize the location of antennas,so as to minimize the number of antennas used.To guarantee the power of transmitter and enhance range resolution,the multiple frequency orthogonal signals have been used to achieve multiple-input and multiple-output function.For the length of array is far less than the scene width,the sub-aperture imaging method is adopted.The curve fitting and PGA(Phase Gradient Autofocus)algorithm have been combined to compensate array error.The simulation results denote the validity of the method proposed in the paper.关键词：aperture synthesis thinned array;radar imaging;multiple frequency orthogonal signal;array error;stratosphere airship4|1177|10更新时间：2025-07-16
- 摘要：A waveform optimal design algorithm is presented in the paper,which utilizes zero correlation zone codes in the multiple-input single-output system used for sparse space-borne radar.It is shown that a single satellite receiver is sufficient for SAR-GMTI.The special bi-phase encoded waveforms are transmitted by multiple satellites,the echoes from all transmit satellites are received by one satellite.After separating by different signal match filters,the main-lobes in the special region of the pulse compression results are almost identical,and the side-lobes are low.And so,the clutter,around the detected cell,can be rejected by the presented algorithm.The simulation results show that the proposed algorithm is effective and feasible.关键词：multiple-input single-output space-based Radar;zero correlation zone codes;waveform optimizing;SAR-GMTI2|1003|0更新时间：2025-07-16
- 摘要：Based on the framework of regularization variation,we proposed a superresolution algorithm of SAR image targets using variable norms.Considering the sparseness of scatterings in the scene,the generalized Gaussian distribution(GGD) is used to model the amplitude of the targets data.Following Bayesian framework,we deduced the relationship between lp norm regularization and the shape parameter of GGD.Under an iterative scheme,we associated the parameter p with the estimated results of each iteration step.The estimated parameter p was then used to modify the model and to construct a superresolution model with variable lp norms.Our method overcomes the shortcomings of the fixed lp norm regularization model,which selects the parameter p by experience.Finally,we demonstrated the performance of our method on simulated and real SAR scene.Experiments show that the method selects parameter p automatically in an iterative way,and produces super-resolved SAR images.关键词：SAR image;superresolution;variable norms;regularization;parameter estimation3|1418|2更新时间：2025-07-16
- 摘要：Due to the limitation of array element number,the conventional velocity synthetic aperture radar (VSAR),may suffer from the azimuth location ambiguity and mislocate fast moving targets.To solve this problem,a novel VSAR named MIMO-VSAR and an optimized array configuration of MIMO-VSAR are proposed based on the multiple-input multiple-output (MIMO) radar in this paper.Compared with the conventional VSAR,the MIMO-VSAR may greatly increase the spatial sampling rate and extend unambiguous velocity estimation range by transmitting and receiving multiple waveforms simultaneously.Furthermore,the analysis and numerical experiments are provided to demonstrate the effectiveness of the MIMO-VSAR and its optimal configuration.关键词：MIMO-VSAR (MIMO-based velocity SAR);moving target detection;unambiguous moving target location2|915|7更新时间：2025-07-16
- 摘要：Silicon oxide ion barrier film was successfully fabricated on the input-face of microchannel plate by magnetron sputtering method.The electron transmission characteristics of silicon oxide ion barrier film were measured and the results were given.The electron-transmission and ion-stopping properties of two different ion barrier films (silicon oxide and aluminum oxide) were analyzed and compared by Monte Carlo simulation method.The electron-transmission property of silicon oxide thin film is better than that of aluminum oxide thin film and the ion-barrier films is inferior to that of aluminum oxide ion barrier film.关键词：microchannel plate;silicon oxide;ion barrier film;monte carlo simulation2|1360|3更新时间：2025-07-16
- 摘要：Since the sensor nodes join or leave the wireless sensor networks (WSNs) frequently,it is necessary to build a secure and efficient group key management system.Based on the key tree and the Chinese remainder theorem,a leveled group key management scheme is proposed.The new sensor may transmit some not sensitive messages by the sublevel group key sent to it,and a group key is sent to the new sensor so as to let it join the WSN in deed after it gets the trust of GCKS.In the leave event,the remaining nodes in the key tree are partitioned by the complete subset method.Then the group key can be updated securely by the method based on Chinese remainder theorem.Finally,we show that the proposed scheme satisfies the desired security properties,such as correctness,group key secrecy,forward secrecy and backward secrecy.The performance analysis shows that the proposed scheme is be applicable to WSNs.关键词：group key management;Wireless sensor networks;Chinese remainder theorem;key tree2|898|6更新时间：2025-07-16
- 摘要：This paper presents a global motion estimation method for diving video.Human body color model is constructed base on the athletes' simple dress in diving video and the area of human body within the foreground and background is picked up so as to improve the efficiency of global motion estimation.Meanwhile,the adjacent frame difference and the direction of the reference module are used to remove the modules which not used in the global motion estimation,so module-matching time is reduced accordingly.Experimental results show that the presented method can not merely reduce the computational complexity of the global motion estimation’s,but also improve its accuracy.关键词：global motion estimation;body color model;motion vector;YCbCr color space;reference module2|704|0更新时间：2025-07-16
- 摘要：The high density and large-scale IC meets lots of problems during test,such as huge amount of test data,long test time and so on.This paper presents a full test scheme by using folding test sets.Firstly several folding test sets are generated by random access scan structure in scan cells which are grouped by input reduction technology to detect most of the faults in circuit under test.Then data in scan cells are modified directly to provide test patterns for the remaining faults.The folding test sets are efficient in detecting faults and they need less control information.Experiment results show that it has shorter test time and higher test data compression ratio comparing with other schemas based on RAS.关键词：input reduction;folding counter;data compression;random access scan2|965|1更新时间：2025-07-16
- 摘要：Cultural relic 3d reconstruction is key techniques of digital museum.The key techniques of 3d modeling and texture mapping are discussed in detail and an feasible project is given in this paper.Some key issues of cultural relic 3D reconstruction for future research are discussed.关键词：cultural relic 3D reconstruction;texture;3D modeling;texture mapping2|2821|10更新时间：2025-07-16
- 摘要：Mobile wireless sensors need to know their locations in many control and monitoring applications.A novel localization algorithm based on Location and Attitude Estimation(LAE)for mobile sensor nodes that can acquire the velocity information is proposed in this paper.Firstly,the relative localization track(RLT),which reflects the shape of true track,is obtained using the velocity information.Then the cumulative error of RLT is corrected while the global optimum solution is obtained by minimizing the difference between RLT and radio localization track.Finally,a more accurate localization result presents itself from the corrected RLT.Simulation results show the performances of our methods in term of accuracy and determinate the parameter the more adapted related to the network configurations.关键词：Wireless sensor networks;mobile node;location and attitude estimation(LAE);node localization2|829|5更新时间：2025-07-16
- 摘要：Traditional mesh-based methods in eigen analysis of waveguide meet two big challengers.One comes from the mesh generation,which is a big difficulty especially in complex geometry.The other originates from the local linear approximation,whose approximation accuracy is poor.So radial basis function method was introduced in this paper,which is a kind of meshless methods with collocation type.Ideas on how to solve eigenvalue problems and detailed implementation procedure were presented with corresponding discrete equations.Comparing to finite element method in the analyzing rectangular,round and L-shaped waveguide,the method suggested in this paper can be realized with low computation and high precision.In addition,the radial basis function method can be implemented more convenient and also can be extended into high dimension problems easily.关键词：radial basis function;meshless method;waveguide;eigen modal2|1139|5更新时间：2025-07-16
- 摘要：This paper presents the generalized Huygens’s principle,which indicates that the electric potential away form and electric charges on the conducts all have the tendency to be a circle or sphere.2|1724|0更新时间：2025-07-16
- 摘要：A transition region extraction and segmentation method based on image fuzzy entropy neighborhood unhomogeneity (NU-TRES) is presented,which is characterized by its speed,ability to deal with noise and robustness.Obtaining a transition region located between the object and background,an optimal segmentation threshold is attained based on the transition region histogram.The membership degree which describes fuzzy division,fuzzy entropy and neighborhood unhomogeneity measurement are created.NU-TRES is not so sensitive to noise as the conventional transition region extraction methods,depending no more on Llow and Lhigh.Analysis and experimental results show that this new algorithm (NU-TRES) significantly outperforms the existing transition region extraction and segmentation methods.关键词：fuzzy entropy;neighborhood unhomogeneity;transition region;image extraction and segmentation2|1108|5更新时间：2025-07-16
- 摘要：An entropy-based hierarchical word clustering algorithm is proposed.Word clusters generated by the clustering algorithm were used as features in Chinese chunking model.Based on words' chunk tags and the theory of entropy,a binary hierarchical clustering algorithm was applied to the words in Chinese chunking corpus.An accelerating algorithm was employed to save the clustering time.With the recognition of name entity and factoid,the new Chinese chunking system was constructed based on maximum entropy Markov models,while part-of-speech features were replaced with the entropy-based word clustering features.Experimental results show that the algorithm increases the efficiency of the word clustering,and the entropy-based word clustering features improve the performance of Chinese chunking effectively.关键词：word clustering;information entropy;Chinese chunking;syntactic function2|1195|4更新时间：2025-07-16
- 摘要：A C-band GaAs pHEMT single-balanced resistive mixer with miniaturized balun is presented.By using lumped-distributed structure,the coupled-line length was reduced by a factor of 11 compared with the conventional λ/4 coupled-line balun.This balun was then used in a resistive mixer to transform the input single-ended signal into differential.The mixer achieved good linearity and port isolation performance with zero power consumption.Test results showed that,with a fixed IF of 160 MHz and 0dBm LO power,the minimum conversion loss is 8.3dB in 3.5~5GHz RF frequency range.The measured 1dB compression point is 8dBm and the LO-to-IF isolation is better than 38dB.关键词：GaAs pseudomorphic high electron mobility transistors (pHEMT);resistive mixer;miniaturized balun;lumped-distributed2|929|1更新时间：2025-07-16
- 摘要：The effect of mutual coupling in linear arrays blocks the estimation of the directions of the incident signals.A new method that focuses on jointly estimating the mutual coupling matrix and direction-of-arrival(DOA),with less computational cost and better robustness,is proposed by considering the characteristics of the mutual impedances in linear arrays.The new method is then extended to general linear arrays,solving the problem of bearing estimation in narrowband linear arrays in the presence of mutual coupling.Simulation results are presented to demonstrate the improvement in the performance of the new joint estimation method in uniform linear arrays and the availability in general linear arrays.关键词：array signal processing;direction finding;mutual coupling;joint estimation4|1483|3更新时间：2025-07-16
- 摘要：Microphone array placement has an important influence on the performance of microphone array speech processing system.For the performance of its time delay estimation(TDE),Cramér-Rao Bound(CRB)of TDE is derived by use of geometrical description of source and microphones,and the effect of microphone array configurations on its TDE performance is analyzed in this paper.Simulation experiments are done on the TDE performance of conventional microphone array configurations.Simulation results effectively verify the conclusion.关键词：microphone array;array configuration;time delay estimation;Cramér-Rao bound2|1242|2更新时间：2025-07-16
- 摘要：In the practice of antenna time domain near field measurement,the biggest errors are introduced by the time base jitter and the amplitude changing of pulse generator.Comparing with the errors caused by amplitude changing,the errors caused by time base jitter are more serious that it can result in unbearable aberrance of measurement pattern.To deal with this problem,the technique of time base correction and amplitude correction is presented in this paper.Besides measuring channel,this technique adds a reference channel in measuring system.Pulse generator’s time base jitter and amplitude changing can be obtained from the reference channel,and be adopted to correct measuring channel’s signal.The practical measuring results have proved this method’s reliability.From comparing experiments,we can find that adopting this technique,the sensitivity of time domain near field measurement is similar to the sensitivity of frequency domain near field measurement,or even better than it.关键词：antenna time domain near field measurement;time base correction;amplitude correction2|1506|1更新时间：2025-07-16
- 摘要：The adaptability testing of model and the optimization of model parameter are the most critical part in system modeling.Residual variance plot,minimum information criteria and AIC criteria are usually adopted in the adaptability testing of forecasting model,which includes disadvantages of big amount of calculating,low veracity and model is not the only.To adopt the trailing of auto-correlation coefficients and partial correlation coefficients to test the ARMA model and then through the F adaptability testing,the disadvantages that the observation sample length is limited,estimation of the partial correlation has error and ARMA model order can not be determined when trailing have been overcome,and then optimized the model parameters by means of scale transformation which have many of the advantages such as ultra-linear convergence and so on,thus the haploid ARMA model with higher veracity can be gained,which is a convincing method of network traffic model adaptability testing and model optimizing and established a stable foundation of the application of network traffic forecasting,abnormity testing and server loading forecast.关键词：non-linear;time series;adaptability testing;ARIMA2|1506|11更新时间：2025-07-16
- 摘要：The problem of determining the local continuity(connection)direction and of the route of the complicated geometrical body formed by characteristics of the same type things in high dimension space,and the problem of finding a satisfactory cover for this complicated geometrical body and deciding whether or not a high dimension point is within the cover are problems difficult to solve within the framework of the traditional mathematical analysis.This paper provides an effective method for the solution to the key technical problems of the above two biomimetics pattern recognition by use of high dimension point distribution analysis method.This technical method is capable of grouping similar samples of the same type in one connected geometrical body,and similar samples of different types in different geometrical bodies,thus achieving the precise recognition of concrete things.关键词：biomimetics pattern recognition;continuity;connection;high dimension space;covered body;neural networks2|829|6更新时间：2025-07-16
- 摘要：A method of anti-compromising emanations of video information based on dither and image fusion is presented.Significant parameters setting conditions,such as pix value of dither image,sizes of font,and dither functions match are confirmed.Image fusion algorithm of useful and dithering image is studied deeply.The correctness and effectiveness of presented theory are proved through simulation and experiment.关键词：video information;anti-compromising emanation;dither;image fusion2|808|1更新时间：2025-07-16
- 摘要：The wobble performance of cone-shaped target with its micro-Doppler signature is researched in this paper.After the interrelated concepts and signal model of micro-Doppler are introduced,the wobble model of cone-shaped target is built,and the theoretical formula of its micro-Doppler is derived separately with the algebra and matrix methods.By the simulation,the micro-Doppler modulation induced by wobble is extracted successfully from the radar echo with time-frequency analysis method,which agrees well with the computing result,and suggests that the wobble model of cone-shaped target and the mathematical derivation of its micro-Doppler theoretical formula are valid.Besides,the influence of velocity and acceleration on micro-Doppler is researched as well as the request of micro-Doppler on the radar return time and illuminating time,and the research results are valuable for the extraction of micro-Doppler.关键词：cone-shaped target;wobble;micro-Doppler2|1248|19更新时间：2025-07-16
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