最新刊期
卷 ， 期 4 ， 1998
- 摘要：This paper proposes a higher order cumulant-based method for harmonic retrieval in non-Gaussian ABMA noise.Hilbert transform is used to transform the real measruements into their complex counter-part,then a kind of elaborately defined fourth-order cumulant of this complex measurements is employed to iden-tify the All parameters of the non-Gaussian noise. After prefiltering the noisy measurements with the identifiedAR polynomial,SVD-TLS method can be applied to retrieve harmonics.This method releases the asymmetrically-distributed assumption of the non-Gaussian noise and is also effcient when there is quadratic phase coupling inharmonics.Simulation examples are presented to support the result of this paper.关键词：harmonic retrieval;Non-Gaussian colored noise;fourth-order cumulant;Hilbert transform2|221|13更新时间：2025-12-08
- 摘要：A novel video coding algorithm based on adaptive blocking regional wavelet transform and dis-crete cosine transform is described in this paper. An adaptive algorithm of motion estimation employs the spatial-temproal correlation presented in motion vector field to reduce calculating complexity. The high energy regions ofinterframe predicted difference are first detected using hierarchical sliding-window region forming algorithm.Thedetected regions are segmented to DWT regions and DCY regions. This scheme reduce the ringing-effects andblocking-effects compared with traditional DWT or DCf coding algorithms . A quantization model based on HVSspatiality-frequency and time-frequency feature is used in coding algorithm.Simulation result shows acceptableimage quality for CIF resolution at low bit-rate and very low bit-rate. This video coding algorithm is downwardcompatible with H.263,and is suited for low bit-rate video conference application.关键词：video coding;wavelet transform;Diserete cosine transform;quantization;Low bit-rate2|77|4更新时间：2025-12-08
- 摘要：The wavelet transform of images can supply information about localization of both space andfrequency.Data compression of vector quantization involved in the wavelet transform domain has been widelyused.After the multresolution pyramidal decomposition of wavelet transform, there aze correlation and spatialconstraints among the wavelet coefficients of subbands. Based upon the more sensivity of human vision to hori-zontal and vertical high-frequency components than diagonal ones, in this paper space-constrained vector quanti-zation using wavelet transform is proposed, which supplies improvements on both coding efficiency and quality ofdecoded images.关键词：wavelet transform;Spatial constraint;vector quantization;Image compression.2|61|13更新时间：2025-12-08
- 摘要：Based on Neyman-Pearson criterion to maximise the probability of signal detection for a givenfalse alarm,and based on the minimum mean-square error between the reconstructed signal and the original sig-nal,this paper presents an optimum wavelet threshold for the estimation of 1/f-type fractal signals embedded inadditive white Gaussian noise.Also presented in this paper are typical computer simulation results to demonstratethe viability and the effectiveness of the proposed optimum wavelet threshold .关键词：fractal signal;l/f noise;signal estimation;wavelet transform2|114|27更新时间：2025-12-08
- 摘要：In this paper, the modeling problem of two-dimensional harmonics is studied . For P-compo-nents two-dimensional harmonics, their two-dimensional characteristic polynomial which has P coefficients is ob-tained.关键词：Two-dimensional harmonics;characteristic polynomial;frequency estimation2|66|4更新时间：2025-12-08
- 摘要：A shape matching algorithm is studied in this paper. Binary rank order transform,a new mor-pholopcal transform, is introduced.Shape matching function is defined, and its properties are discussed. A set ofshape templates is constituted,and a new scheme of shape recognition is proposed,which is simple , high effi-cient,and easy to implement parallelly. Finally, the new algorithm is used for recognition of indicatory trafficsigns, the experimental results show its robustness and effectiveness .关键词：shape matching;mathematical morphology;Shape matching function;Shape template;Binary rank order transform2|154|10更新时间：2025-12-08
- 摘要：In this paper,the effect of diagonal loading on adaptive array performance is analyzed . The di-agonal loading level threshold is defined under the measure that the adaptive array SINR loss is less than 3dBand is analyzed for different interference cenarios.The results are meaningful for determining the loading level.Based on these results, an effective approach of nonzero initialization for recursive LS adaptive beaforming algo-rithms is proposed.关键词：Adaptive array;Diagonal loading;Diagonal loading level threshold2|259|30更新时间：2025-12-08
- 摘要：Instead of analog device and general purposed DSP previously used in real-time MTD radarsignal processing , an ASIG-based radar signal processing system is proposed. In this system, the radar back-ground generator,the clutter-map unit former, the moving target signal extractor, the video signal integrator, theCFAR （ Constant False Alarm Rate）operator, the timer and controller are all designed by ourselves with FPGA.This system is now thrown into application with high performance, well-resistance to EMI, less circuit area, easeto debug .关键词：radar;MTD;DSP;ASIC;FPGA2|203|9更新时间：2025-12-08
- 摘要：A wavelet-based fuzzy neural network（FWNN） for the interval estimation of processed data isproposed in this paper.The structure of the FWNN is based on the fuzzified wavelet neural network and thelearning algorithm is LP method which is an interval learning algorithm that makes the outpot of the trained netan interval and which provides an alternative approach to get the wavelat coefficient .关键词：模糊子波神经网络;区间学习算法;LP2|119|72更新时间：2025-12-08
- 摘要：In this paper, we propose a Code Division Multiple Access（ CDMA） based system to providevariable rate services by varying the number of codes assigned to a user. For the macro- , micro-, picrocell chan-nel models, an approximation to the bit error probability in different environments is given which depends only onthe first and second order moments of the multipath energies. We then analysize the BER’ S performance of asystem with integrated voice and video traffics.关键词：CDMA;Integrated traffics;multipath channel2|33|0更新时间：2025-12-08
- 摘要：Many recent researches in telecommunication area take lots of attentions to long range depen-dence（LRD） in traffic . In this paper, we study the impact of LPD on queuing performance from a lot of simula-tion experiments which are designed carefully . We draw some conclusions different with those in former papers ,and analyze the reasons why those papers gave that kind of doubtful ideas. our results indicate that the correla-tion characteristic of traffic is very important, and the short range dependence is a more dominant characteristicthan LBD.关键词：: Communication networks;autocorrelation;Long range dependence;Traffic modeling2|66|6更新时间：2025-12-08
- 摘要：Nowadays the self-healing techniques in ATM VPX（ VP cross-connect） networks are highlycondidered. However in previous liteialure,the normal control and self-healing control are separately investigat-ed. In this paper, integrated control strategies for ATM VPX survivable networks are proposed , which combine thenormal control and self-healing control in a unified way to reduce the control complexity . Through computer sim-ulation, the operationability and validity of these strategies are verified . These strategies are able to operate underboth normal conditions and catastrophic failure situations.These strategies will make it possible to plan and de-sign cost-effective survivable networks.关键词：ATM VPX survivable network;Integrated VP-based control;Normal control;Self-healing control2|37|3更新时间：2025-12-08
- 摘要：This paper introduces a timing recovery technique for CBR traffic in Wireless ATM Networks .A novel technique named Asynchronous Residual Time Stamp（ ARTS）combined with stuffing technique is pre-sented , the implement scheme is also discussed . In addition , areceived First-In-First-Out buffer is implemented toabsorb the cell delay jitter at the destination terminal,the regularity in the previously received ARTS is used toestimate the loss of the ARTSs . From the analysis and simulation niulation results, we know that the timing recovery tech-nique for CBR traffic proposed by this paper is adequate for Wireless ATM Networks , and it is compatible withSRTS for B-ISDN/ATM well.关键词：timing recovery;ARTS;Wireless ATM networks2|42|2更新时间：2025-12-08
- 摘要：This paper proplses a model of routing control and accesstraffic control to solve the dynamic assignment of the capacity for communications network.Firstly , equation of system status（ estimating busy-circuitnumber of trunks）are derived, and at the same time , the control strategy os assessed.Secondly.the optimal model for the dynamic assignment of the capacity is designed.and for the "fairness" , quadratic programming model isgiven. Finally , the paper discusses the realization mechanism of the realization mechanism of the above methodology and illustrates the pracgti-cability by instances.关键词：状态方程;路由控制;容量动态分配2|33|1更新时间：2025-12-08
- 摘要：This paperdiscusses fundamental frameworks and systems of Telemetry,Telecontrol , Position-finding and （remote sensing ） Picture transmission （TTPP） used in vehicles.The three frameworks are distribut-ed TTPP, unified carrier TTPP, unified spread-spectrum TTPP. But only unified frameworks are discuesed em-phatically.The principles.performance of unified frameworks are discussed,Some key techniques and miscella -neous derived techniques are given.关键词：Telemetry Telecontrol Position-finding;Picture transmission2|247|23更新时间：2025-12-08
- 摘要：In this paper,the theory of MPEG-2 source decoding is studied , and how to implement anMPEG-2 source decoder is presented also . The emthod of synchronization of audio and video is described in de-tails.The source decoder is completely achieved,.and picture can be shown in real time . The decoder will bemade as a DVD product.关键词：:Source decoding;Transport stream;MPEG-2;Synchronization of audio and video2|63|4更新时间：2025-12-08
- 摘要：Image compression using wavelet is very attractive . In this paper, lattice quantization and run-length code are integrated to effciently encode wavelet coefficienis, in which hybrid entropy code is used to en-code non-zero lattice points, and run-length code is used to encode zero lattice points resulting in high compres-sion.The coder’ s output bit rate can be flexibly controlled.The operational complexity is very low due to the fastalgorithm of lattice quantization.The coder’s performance is superior to conventional DCF,pure lattice quantiza-tion, and is competitive with EZW algorithm.关键词：wavelet transform;Lattice quantization;Hybrid entropy coding;image coding4|58|6更新时间：2025-12-08
- 摘要：In this paper, we introduced an algorithm for image compression based on tree-structuredwavelet decomposition . Under some special energy rules, it can implement the subband coding according to theimage features adaptively.The experiments for textured images shou that,this method is outstanding at compres-sion ratio , visual effect and SNR. So, it is valuable to the second generation image compression schemes based on edge texture coding respectively.关键词：纹理;图像压缩;树状小波分解;子带编码2|98|5更新时间：2025-12-08
- 摘要：Based on human detection, a wavelet image coding method using vector quantization（ VQ）is presented.With human visual characteristics to best advantage, recontructed image with a high compassiverate can still hold fairly good subjective quality.关键词：人脸检测;小波编码;矢量量化2|112|18更新时间：2025-12-08
- 摘要：A new synchronous flow control scheme for ATM retworks is proposed in this paper. Thescheme could allocate bandwidth fairly and efficiently.The rate of an ABR source would go up increasingly. Byintroducing Vinual Nodes. the transient durations experienced by ABR connections are further reduced.The per-formance of SER scheme is investigated with simulations . As a result , transient durations are very short . Thelength of queues accumulated at switch ports are also very short.关键词：ATM;ABR;VBR;flow control2|25|1更新时间：2025-12-08
- 摘要：A cluster-based WDM network is proposed in this paper, where each user is equipped with afix tuned receiver and a limited tunalbe transmitter.The network achieves constant maximum hop of 2. It adoptsa systematic channel assignment algorithm （ CAA） to minimize the tuning range of each transmitter meanwhileminimizing the average hop. Analysis and mumerical results show that the network obtains equivalent single hopprobability among clusters under the uniform traffic . Furthermore,its basic performance such as average hop andmaximum throughput , is almost only related with wavelength number, having little to do with the user number.关键词：multi-hop;WDM;Tuning range2|13|0更新时间：2025-12-08
- 摘要：In this paper, we study the parameter algorighm of the superposition process of interruptedPoisson processes.and obtain the average lengths of overload peried and underload period, the packet arrivalrates of overload period and underload period and the packet loss rate.关键词：Interrupted Poisson process;ON-OFF source;Superposition;Active period;Silence period2|110|3更新时间：2025-12-08
- 摘要：This paper describes a nonlinear short-block data estimation technique（NSBE）suitable for theHF modem,with which the known training symblos are used to track the channel characteristics and to detect theunknown data symbols.The adoption of the decision feedback type may reduce the length of the data block, sothat an algorithm of a simplified Cholesky matrix resolution is used. Computer simulation indicates that thisscheme facilitates to effectively eliminate the intersymbol interference in the HF channel and it can be applied tothe high-speed serial HF modem.关键词：Data transmission;signal detection;Channel evaluation2|43|4更新时间：2025-12-08
- 摘要：Based on the sigrial model, being not related to calibration method , the uncalibrability of thephase error of linear array is analyzed in this paper firstly. Then,the performance of the constraints which areconstructed to ealibrate the phase error are analyred. The formulas of the constraints’ performance are given .Computer simulation results show the correctness of analysis .关键词：array processing;error calibration;performance analysis2|124|18更新时间：2025-12-08
- 摘要：In this paper,a filtered-LMAD algorithm and its normalized form are proposed for adaptive ac-tive noise control in Non-Gaussian stable environments. Simulation results indicate that the proposed algorithmsconverge faster than the conventional filtered-LMS and normalized filtered-LMS algorithms do.关键词：Active noise control;adaptive signal processing;Filtered-LMAD algorithm;Filtered-LMS algorithm2|119|2更新时间：2025-12-08
- 摘要：Digital interleave in conjuction with Forward Error Correction （FEC） is an effecient method todeal with burst errors on data transmission. This paper introduces a mathematical idea of permutation replacement into convolution interleaver.Based on this view poiint , we present a new construction to realize the convolution in-terleaver which is similar to the T-switch in programming control switch machine. The method in this paper issimpler than that in GA scheme, but the effect is the same .关键词：Digial interleave;Permutation replacement;HDTV4|159|6更新时间：2025-12-08
- 摘要：Based on the possibility theory,a new partition coefficient is introduced. By combinating thisnew partition coefficient with the partition coefficient defned by J . C . Bezdek , we give a new cluster validity func-tion. Experimental results show this cluster validity function’s effectiveness and robustness.关键词：fuzzy clustering;partition coefficient;Cluster validity function2|474|91更新时间：2025-12-08
- 摘要：Based on a criterion for effective generalization of networks, several practical methods toimprove the generalization performance of feedforward neural networks are proposed,including enhancing thefeature extractor and classifier and modifying the activation function of neuron.The simulation results on hand-written character recognition confirm that our models have good generalization abilities.关键词：: Feedforward neural networks;Generalization;feature extraction;Classification;activation function2|163|10更新时间：2025-12-08
- 摘要：In this paper,a connection model of CMAC network is proposed,which is composed of A/Dconverters,decoders ,OR-AND Boolean function network,memory,and a Adaline（Adaptive Linear Element） .The model is easily realized by hardware . Results of computer simulation experiment for a function approzimationProblem show effectiveness of the model .关键词：neural network;CMAC;Boolean functions2|32|1更新时间：2025-12-08
- 摘要：This paper presents many schemes called directed signature schemes, only specific receivercan authenticate the truth of signature . Five directed signature schemes are proposed based on EIGamal type sig-nature schemes and corresponding signature sehemes with message recovery （ called MR type signatureschemes） , and their security is analysed and discussed.关键词：计算机网络安全;数字签名;消息认证2|105|16更新时间：2025-12-08
- 摘要：The distribution of dimensions of linear structure sets nicture sets of Boolean functions is discussed.关键词：自对偶点;反自对偶点;线性结构2|82|5更新时间：2025-12-08
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