最新刊期
卷 32 ， 期 7 ， 2004
- 摘要：Based on a new theory model-BPR(Biomimetic Pattern Recognition),a face recognition system is implemented.In order to compare the recognition performance of it with that of some TPR (traditional pattern recognition),such as NN-based method and SVM-based methods with different types of kernel functions,using the ORL face database,we analyze the misclassification rate and false acceptance rate at the same level of the correct recognition rate by adjusting parameters of different algorithms.Comparison results show that our method is superior to the other two methods.关键词：biomimetic pattern recognition;face recognition;principle component analysis;nearest-neighbor classification;support vector machine2|2381|29更新时间：2025-07-16
- 摘要：Group signature schemes allow any member of a group to sign message on behalf of the group.In case of dispute,the group manager can reveal the identity of actual signer.Revocation of membership is an important problem in group signature schemes,but among the existing group schemes,there is not any scheme which can safely delete the group member without changing secret keys of the other available group members and the cost of deleting group member is high.A new scheme based on Chinese remainder theorem is proposed in this paper and it has three merits.First,the group manager can safely add or delete members while keeping the secretkeys of the other available members unchanged.Second,only mutiplitation is needed and the length of group center's public keys is unchanged during the revocation.Third,the security of this scheme relies on the factoring of large integers.关键词：group signature;Chinese remainder theorem;revocation3|1698|29更新时间：2025-07-16
- 摘要：It is pointed out that the two stream ciphers proposed respectively in "Generating nonlinear feedback stream ciphers via chaotic systems" and in "The theoretical design for a class of new chaotic feedback stream ciphers" have the property that the frontal values of the output sequences of the two stream ciphers are not sensitive to the least significant bits of the key.So they can be attacked effectively by the divide-and-conquer attack,which attacks the most significant bits of key at first and the least significant bits of key secondly,with the known chaotic transformations and known plaintexts.An optimal exhaustive attack with the minimum computing complexity is proposed under the condition that the distribution of the key is known.Furthermore,an improved divide-and-conquer attack is proposed and its computing complexity and success probability is analyzed.关键词：chaotic sequence;stream cipher;divide-and-conquer attack;exhaustive attacking;improved divide-and-conquer attack2|1224|24更新时间：2025-07-16
- 摘要：A buyer wishes to show she has enough money in her account without revealing her money to buy some commodities.Therefore,a tool is needed for proving that a committed number is in a specific interval.Up to now,most of such tools were either inefficient or inexact.In this paper,we present a new simple protocol,which is exact and more efficient than the previous ones.The protocol is suited to be used in electronic cash,group signatures,publicly verifiable secret encryption,etc.关键词：zero-knowledge proof;discrete logarithm;trap-door commitment2|1119|8更新时间：2025-07-16
- 摘要：The research of information model on service management layer can bring forward such benefits as:unified service planning and provisioning,consistency among the functionality models in the service supply chain and mapping correctness from requirements to management functions.In this paper,we have followed ITU-T M.3020 "requirement,analysis and design" methodology and proposed a lifecycle-based generic management information model of F interface,which adopts a top-down view to define managed objects in the different segments of service lifecycle.The model can be used as a meta-model to direct the development of service management systems in a real environment.关键词：service management;information model;service lifecycle;meta-model2|902|1更新时间：2025-07-16
- 摘要：Network delay jitter often leads to the discontinuity of media playback.An improved dynamic playback algorithm is proposed in order to keep multimedia playing smoothly,which deals with the problem from the perspective of an end system.In the algorithm,playback rates of multimedia are variable according to the occupied buffer level with an intention of eliminating buffer underflow or overflow.The playback rates are chosen based on the requirement of the intra-media synchronization.To determine the thresholds of the occupied buffer level,a queuing model is established.Based on the analytic results,suitable thresholds can be determined according to the system parameters.Simulation results show the algorithm wins an advantage over Yuang's.关键词：intra-media synchronization;buffer level;dynamic playback2|1027|5更新时间：2025-07-16
- 摘要：A new codebook design algorithm is proposed for vector quantization image coding based on the ant colony optimization.Inspired by the ability of real ants to find the shortest path through the laying down of pheromone and to cluster corpse in the nest through the picking-up and dropping of small objects by individual ant,we proposed the ant clustering based codebook design algorithm with emphasis on the appropriate design of the dropping probability,the tabu list as well as the way pheromone was updated,and the determination of the corresponding parameters.Experimental results are very encouraging and it is found that the new algorithm outperforms the latest evolutionary simulated annealing and stochastic competitive vector quantization codebook design,the improvement of pixel signal-to-noise ratio exceeds 2dB compared with the conventional LBG algorithm.关键词：ant colony algorithm;image compression;vector quantization;codebook design2|960|10更新时间：2025-07-16
- 摘要：Hierarchical MRF image model has causality property between layers,and the causality is consistent with the characteristics of images.So the processing time of such models is much less than that of the plain MRF models.An expectation maximization(EM) algorithm estimating parameters of incomplete hierarchical MRF model,which is a new hierarchical MRF image model we presented,is deduced.The advantage of less time cost possessed by the non-iterative algorithm of hierarchical models is inherited.Time is further reduced due to simplified model structure.The interaction between neighbor nodes on the top layer is considered,which results in more accurate estimate values with less computing cost.The algorithm is used in unsupervised image segmentation.The experimental results demonstrate that it is characterized by high speed and better results compared with that of hierarchical models.It is more fit for large images.关键词：incomplete hierarchical MRF;expectation maximization(EM) algorithm;unsupervised image segmentation2|1082|2更新时间：2025-07-16
- 摘要：The statistical characteristics of some non-Gaussian noises were analyzed.On this ground the moments estimations were used to deduce the models transformation algorithms of these noises.The inertialess nonlinear transformer was employed to research the maximum likelihood detections of deterministic signals;and the recurrence was adopted to study the maximum likelihood estimations of cosine signals parameters in bimodal noises;on these grounds the validities of models transformation algorithms were verified by ways of analyzing the performance of signals detections and parameters estimations.The simulation results indicated that it was exact to regard the bi-peak noises as bimodal noises.Thus it was demonstrated that the thought of bimodal noise is practicable.关键词：non-Gaussian noise;bimodal noise;maximum likelihood criterion;inertialess nonlinear transformer2|1298|3更新时间：2025-07-16
- 摘要：Using the concepts and algorithms related to Grobner basis and syzygy module in computing algebra,we propose orthogonalized approach for the polyphase matrix,and symmetric orthogonal M-band wavelets with arbitrary regularity are achieved.The drawbacks that the computational process of the existing methods is complicated and linear-phase can not be achieved are avoided.Furthermore,the presented wavelet filters contains free variables when the associated scale filter coefficients involve parameters.Therefore,M-band wavelets with free variables via practice requirement is also developed.关键词：M-band orthogonal wavelets;parameter;Grobner basis;syzygy module4|643|0更新时间：2025-07-16
- 摘要：A novel robust watermarking scheme is proposed,in which a permuted watermark is embedded into a permuted image.We use a chaotic map to permute the image and the watermark data.and embed the watermark by resetting the relationship of the pixels instead of changing the pixels individually.A novel idea of remainder decision and a spatial-based error correcting is realized with good performance in the extracted phase.The watermark embedded to the image is imperceptible and the extracted watermarks are still recognizable when JPEG compression ratio reaches 27.4% or after severe zero-mean AWGN pollution.If well synchronized,this algorithm can also have good robustness to geometrical attacks such as cropping,scaling and rotating.关键词：remainder decision;error correct;chaotic permuting;robust watermark2|1008|2更新时间：2025-07-16
- 摘要：The convergence of the iterative process ensures the validity of fractal decoding.To study the convergence of decoding process,the transform in fractal encoding must first be presented with matrix.In this paper,matrix representation of fractal encoding of digital grey level image is put forward and a method to compute spectral radius of the matrix based on the theory of directed graph is also presented.关键词：fractal image encoding;convergence;directed graph;strong connectivity2|1299|1更新时间：2025-07-16
- 摘要：A new weighted mean filter,histogram weighted mean (HWM) filter,is proposed to restore images corrupted by salt-pepper impulse noise.The idea is based on weighted mean filter,which uses the histogram function of the corrupted image as weight.Experimental results demonstrate that the proposed HWM filter is effective androbust for different noise ratio,ranging from 5% to 90%.When noise ratio exceeds70%,HWM filter gives superior performance compared with other known filters.关键词：histogram;image processing;histogram weighted mean filter.2|1116|5更新时间：2025-07-16
- 摘要：This paper introduces the concept of application server in Next-generation Networks and the overload control problem,and then analyses new requirements to overload control.Furthermore,the overload control framework of application server is proposed.Under these backgrounds,the performance metrics,the overload detection method and the overload control algorithm are discussed.The theoretic analyses and simulation results prove the effectiveness and fairness of the algorithm.关键词：next-generation networks;application server;overload control;QoS2|900|0更新时间：2025-07-16
- 摘要：For the segmentation of the small moving targets in the infrared image sequences,the features of the targets in the sequences are analyzed.It can be observed that the targets have their own intensity distribution in a single frame and their intensities are continuous among several adjacent successive frames.So a new method that integrates single frame processing with temporal filtering is proposed.The method can improve the precision of target segmentation,and is verified by a larger number of results of experiments and comparisons.关键词：background suppressing;target enhancing;temporal filtering;image fusion;target Segmentation2|908|8更新时间：2025-07-16
- 摘要：First,a new class of gray scale transformation equation composed of the direct & 1-order polynomial mixed mapping are proposed,and it improves the existing image information restoration algorithm based on long-range correlation.The improved method not only overcomes the poor smoothness performance caused by the direct mapping,but also solves the possible serious bug brought by 1-order mapping when the denominator of the polynomial equals to zero.Second,a novel improved genetic algorithm used in the search of the remote window in the image restoration is presented.The new algorithm avoids the laboriousness of ergodic search and overcomes the blindness and instability of the random searching.Compared with the simple genetic algorithm,the improved genetic algorithm speeds up the convergent process and improves the accuracy.The experimental results show that the satisfyactory performances can be obtained by means of the two improvements above.Especially the novel genetic algorithm demonstrates good robustness in the optimal search of the whole.关键词：image information restoration;genetic algorithm;long-range correlation2|947|2更新时间：2025-07-16
- 摘要：Multi-channel acoustic echo cancellation(AEC) systems suffer from the non-uniqueness problem of the adaptive identification solution because of the correlation of the input signals.This paper investigates integrating a simplified blind signal separation (BSS) model into the stereophonic acoustic echo cancellation (SAEC).The integrated new structure translates the SAEC problem into two single-channel AEC problems so as to avoid the NUP and doesn't influence the audio quality. The simulation results improve the effectiveness of the new structure.关键词：acoustic echo cancellation;adaptive filter;blind signal separation2|1044|1更新时间：2025-07-16
- 摘要：This paper proposed a new method of designing a single-scaling wavelet frame network-based adaptive observer for a class of MIMO nonlinear systems,which can estimate the states of a class of non-affine systems with uncertainties or unknown nonlinearities.The wavelet network weights are tuned on-line,with no off-line learning required.The robustifying term in the observer can reduce the error brought by the wavelet network approximation greatly.The overall adaptive scheme is shown to be uniformly ultimately bounded.Simulation results have verified the performce of the observer proposed.关键词：nonlinear system;single-scaling wavelet frame;adaptive;state observer;parameter estimation2|987|0更新时间：2025-07-16
- 摘要：Various digital watermark signals involved in digital watermarking algorithms are discussed and the requisite characteristics of a watermark signal are summarized.The chaotic watermark signal based on chaotic sequences is proposed.This chaotic watermark signal has some promising characteristics in comparison with other watermark signals.Firstly,it is easy to be created by using 1-D chaotic maps only.Secondly,it can create numerous chaotic watermark signals whose auto correlation is strong and cross correlation is weak.Finally,the chaotic watermark signal is difficult to be decoded if the chaotic map model and its parameters are unknown.Chaotic watermark signal can meet the tremendous demand in the applications and the standardization of watermark signals will help watermarking technology to come into realization.关键词：digital watermarking;chaotic;spread spectrum;watermark signal;watermark standardization2|1310|14更新时间：2025-07-16
- 摘要：Shot retrieval plays a critical role in content-based video retrieval.Motivated by the theory of optimal matching in bipartite graph,we propose a novel approach based on the Kuhn-Munkres algorithm for shot retrieval.In contrast to existing algorithms,the proposed approach emphasizes one-to-one mapping among frames between two shots for effective similarity measure.A weighted bipartite graph is constructed to model the similarity between two shots:every vertex in a bipartite graph represents one frame in a shot,and the weight of every edge represents the similarity value for a pair of frames between two shots.Then Kuhn-Munkres algorithm is employed to compute the maximum weight of a constructed bipartite graph as the similarity value between two shots by guaranteeing the one-to-one mapping among frames.To improve the speed efficiency,we also propose two improved algorithms.Experimental results indicate that the proposed approach achieves superior performance than some existing methods.关键词：Content-based shot retrieval;optimal matching;Kuhn-Munkres algorithm;improved algorithm2|1508|9更新时间：2025-07-16
- 摘要：The problem of calculating discrete Fourier transform in polar coordinate systems,which is called DPFT here,has been given considerable attention in many fields such as antenna,image registration and image retrieval.But the direct computation of DPFT is very time-consuming because of no X-Y separability.This paper proposes an improved fast 2D DPFT algorithm which aims at 2D real array data and can be realized by only 1D calculations.This decreases the overall computational complexity significantly and suits more for real-time signal processing.Compared with the direct calculation,the experimental results demonstrate the good performance of the proposed algorithm.关键词：polar Fourier transform;shift DFT;Chirp-Z transform2|1310|1更新时间：2025-07-16
- 摘要：Novel models and algorithms for real-time multicast routing should be presented because the additive metric of cost cannot manifest the essential characteristics of real-world network,especially for the concave bandwidth.This paper substitutes available bandwidth for cost as the primary metric and considers the other two significant constraints in real-time multicast:delay and delay variation.Based on these three metrics in the mean time,two novel real-time multicast routing algorithms with polynomial time complexity are proposed.The comparison of performance between these two algorithms is given as well.The novel algorithms effectively reduce the complexity of those algorithms related to delay and delay variation by analyzing and obtaining the relationship between per-path delay and two tolerances.Accounting for adopting practical metrics,the novelalgorithms are quote worthy to be recommended.关键词：real-time multicast routing;available bandwidth;delay;delay variation2|907|1更新时间：2025-07-16
- 摘要：A quantum identity authentication scheme which is independent on trusted-party is proposed.The main characteristic in the proposal is that the authentication key can be obtained dynamically.The security is guaranteed by the no-cloning theory and the dynamical feature of the proposed scheme.关键词：identity authentication;quantum cryptography;cryptography2|1453|5更新时间：2025-07-16
- 摘要：The paper presents a novel channel assignment scheme,namely classified compact dynamic channel assignment (CCDCA) scheme for cellular mobile communications systems.The so-called classification is that a cell is classified as the hot and cold based on the definition of "cold" and "hot".The so-called CCDCA is that different compact strategies and allocation are thus derived,then the information obtained from the previous "cold" state is used for channel assignment in the "hot" state.The scheme combines local information with the whole,and can guarantee high quality of service (QoS) and low service deviation (SD).A two-dimensional Markov chain model is developed to analyze the threshold and its main parameters are derived for the scheme,though it is also applicable to analyze channel assignment schemes.By simulation,the CCDCA is shown to be superior in terms of call blocking probability and spectrum utilization.The simulation also shows that the model can match practical system quite well.关键词：cellular mobile communications;dynamic channel assignment;Markov chain2|948|4更新时间：2025-07-16
- 摘要：A new blind source separation method based on ridge characterization extraction is presented.The stationary phase method proves that in the asymptotic limit,the behavior of the continuous wavelet coefficients shows strong ridge character.By extracting the ridge characterization of each signal component,some parameters of the signal component can be extracted and used in reconstruction of the original signal.This feature can be used in blind source separation of a set of instantaneous linear mixtures of non-stationary signals.Numerical simulations are provided.关键词：continuous wavelet transform;ridge extraction;blind source separation2|1027|4更新时间：2025-07-16
- 摘要：Voice conversion technology transforms one person's speech pattern into another pattern with distinct characteristics.The goal of a voice conversion algorithm is to achieve a transformation that makes the speech of the first speaker sounds as though it were uttered by the second speaker giving it a new identity,while preserving the original meaning.This paper introduces some current studies on voice conversion technology,which focus on various types of algorithms implemented in voice conversion area.Different evaluation methods for voice conversion performance are described.A technological outlook for this speech technique is given in the last section.关键词：voice conversion;speech spectrum;pitch contour;glottal excitation;codebook mapping;artificial neural network;Gaussian mixture model;hidden markov model2|2352|13更新时间：2025-07-16
- 摘要：In this paper,we investigate pilot-channel-assisted coherent demodulation in wideband code-division multiple-access (WCDMA) uplink and propose a novel parameter optimization scheme.The moving average length of channel estimator and the pilot-to-data channel power ratio are optimized analytically under the criterion of minimum bit-error-probability (BEP) for given signal-to-noise ratio (SNR).关键词：WCDMA;channel estimation;power ratio2|941|0更新时间：2025-07-16
- 摘要：The performance of the existing filters will badly deteriorate in removing additive impulse noise,such as Gauss impulse noise and long-tailed impulse noise.Therefore,a new method for image restoration is presented in this paper.The new method can be used to estimate histogram of original image through input image,and gets a membership through this histogram by using fuzzy set theory,then establishes a weighted fuzzy mean filter through this membership.The new method effectually utilizes the prior knowledge of the original image,and can adaptivly adopt different filter scale in the light of character divergence of image region and intensity of impulsive noise.The performance of the new method is compared with conventional filters and available fuzzy filters.Experimental result shows that the performance of the new method is better.关键词：histogram;impulsive noise;fuzzy filter;image restoration2|1336|1更新时间：2025-07-16
- 摘要：In many printer and publishing applications,it is desirable to embed data in halftone images for copyright and authentication purposes.In this paper,a novel data hiding algorithm for halftone images is proposed.The digital watermarking is embedded by DCT mid-frequency coefficients comparison method.Before embedding,the digital watermarking is transformed into binary data,and then they are embedded into DCT mid-frequency subbands by changing the order of these coefficients.Experiments show that this algorithm is robust for printing and scanning,and the original picture is not needed in the recover progress of the digital watermarking.This algorithm can also be used for forgery detection in certificates.关键词：printing/scanning;digital watermarking;halftone images.4|1217|7更新时间：2025-07-16
- 摘要：Rate control is a key module in a video encoder, and plays an important role in quality of video services.This paper provides a frame-layer variable bit-rate (VBR) rate control method without pre-analysis and pre-coding.Quantization parameters (QPs) are initialized in frame layer according to previous coding statistics firstly;then target bit is calculated according to rate-distortion (R-D) model,and a feedback mechanism regulates QPs and accommodates the target bit to buffer constraints.Simulation results show that the proposed method can not only meet the global bit budget and buffer conformance,but also result in a constant picture quality.Additionally,its low computational complexity makes it applicable to real-time video coding.关键词：rate control;variable bit-rate;target bit allocation2|1162|2更新时间：2025-07-16
- 摘要：A novel architecture is proposed to implement FFT/IFFT processor with CPLD devices.The new architecture combines the traditional pipeline structure with recycled structure effectively and meets the requirement of 802.11a[1] standard.Especially,it utilizes far fewer logic cells than other architectures.In order to verify the efficiency of the proposed structure,we implement the proposed structure and the traditional pipeline structure with CPLD devices separately,and the experimental results show that the proposed structure hereof has superiority in application.关键词：FFT;CPLD;recycled architecture;pipeline architecture2|1112|0更新时间：2025-07-16
- 摘要：In this paper we propose the Degree Adaptive flooding Broadcast (DAB) strategy for Ad Hoc networks to efficiently reduce the broadcast overheads in the network.Based on the degree of the nodes,DAB decides which nodes need to re-transmit and which nodes only need to receive.The higher the neighbor node's degree,themore nodes it can cover,so this kind of nodes can be selected to resend the broadcasting messages in the networks.The simulation results show that DAB strategy outperforms the ordinary flooding broadcast method for the Ad Hoc networks.2|1146|6更新时间：2025-07-16
- 摘要：In the field of cluster analysis,objective function based clustering algorithm is one of widely applied methods so far.However,this type algorithms need the prior knowledge about the cluster number and the type of clustering prototypes,and can only process data sets with the same prototypes.Moreover,these algorithms are very sensitive to the initialization and easy to get trapped into local optima.To this end,this paper presents a novel clustering method with network structure based on clonal algorithm to realize the automation of cluster analysis.Since the new algorithm combines the clonal selection algorithm and forbidden clonal operation,the obtained network has not only the specificity but also the tolerance of immunity.By analyzing the neurons of obtained network with minimal spanning tree,one can easily get the cluster number and related classification information.The test results with various data sets illustrate that the novel algorithm achieves more effective performances on cluster analyzing the data set with mixed numeric values and categorical values.关键词：cluster analysis;numeric feature;categorical feature;clonal selection;forbidden clone2|1283|13更新时间：2025-07-16
- 摘要：In this paper,we briefly introduce several methods for spatial error concealment,and then propose the algorithm of multi-directional and variable-interval interpolation for spatial error concealment.The proposed method chooses both interpolation directions and reference area according to the edge feature of the neighboring blocks.The experimental results show that the quality of the image processed using the proposed error concealment method is significantly improved.关键词：error concealment;spatial interpolate;video communication2|838|2更新时间：2025-07-16
- 摘要：A new method for meaningful regions segmentation in natural color image is proposed in this study.After edge detecting in term of phase congruency,long edge lines are clustered using K-means algorithm based on the joint distribution of their color in image space and in color space to get meaningful seeds,while short ones are merged to eliminate the negative affection causing trivial features in images.Region growing technique is employed in color space to achieve the final segmentation results with the properly selected seeds.The proposed method overcomes the disadvantage of traditional region growing method,and applies it to color images.The meaningful segmentation results are consistent with those executed by people and have shown feasibility and effectiveness to various natural color images.关键词：natural image segmentation;phase congruency;edge detection;region growing2|1357|10更新时间：2025-07-16
- 摘要：This paper proposes the dynamic matrix control of heat supply object based on the feature of heat supply process.The use of simplified model and prediction error correction improves conventional control algorithm.It introduces the principle of model simplification,and derives immediate control.In order to compensate model mismatch after simplification,the prediction model error is used to replace model error to carrly out correction of optimum control of system.The prediction error correction is based on time series analysis,parameters estimation and optimum prediction principle.In the end of the paper,simulation of heat supply object about above-mentioned algorithm is carried out.Simulation results prove that algorithm is effective in ensuring real-time control,improvement of tracking and robustness property.关键词：predictive control;model simplification;prediction error;simulation2|933|1更新时间：2025-07-16
- 摘要：For the design and operation of high-speed broadband network,survivability and efficiency are two essential problems.How to satisfy the different service requirements as well as reduce the cost of network becomes increasingly concerned.In this paper,we propose a new restoration strategy which is based on combination of the pre-planning and pre-configured methods.Through the performance analysis in fixed span capacity network model,it shows that high efficiency can be obtained from a trade-off between protection ratio and the length of restoration path.关键词：pre-planning;pre-configured;mesh-network;restoration strategy2|874|2更新时间：2025-07-16
- 摘要：In this paper,we proposed a fast algorithm for blind equalization.This algorithm is essentially different from usual ones for blind equalization in the sense that it does not resort to any merit function and corresponding minimization algorithm so that it completely avoids the difficulty of global convergence.The new algorithm is based on a priori knowledge of some statistical properties of the channel input sequence and fully uses the relation between the channel input sequence and the observed output sequence.It only uses operations for comparison and few multiplication and addition so that the computational costs are much lower than that of usual blind equalization algorithms.关键词：equalization;cost function;global convergence2|703|1更新时间：2025-07-16
- 摘要：The design,analysis and application of DNA cryptosystem just begin to be explored all over the world.A cryptosystem based on recombinant DNA technique is presented.The encryption/decryption and digital DNA coding are designed.The security is analyzed.This work is inventive.关键词：Recombinant DNA technique;encryption;decryption;key;security3|1365|2更新时间：2025-07-16
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Performance Analysis of UQPSK Carrier Acquisition and Tracking Algorithm in Satellite Communications
摘要：An UNBALANCED QPSK (UQPSK) signal format is a QPSK signal where the two orthogonal components of the carrier have unequal power and are modulated with independent binary data streams of different rates.This transmission scheme is most useful when the data of two different sources with possibly varying rates have to be transmitted in the same frequency band.This signal design was used in the Tracking and Data Relay Satellite System (TDRSS) and the Navigation Satellite Timing and Ranging Global Positioning System (NAVSTAR GPS).To suit for the UQPSK-DS-SS adopted in S-Band forward link of TDRSS,this paper introduces a whole digital implementation of TDRSS IF carrier acquisition and tracking system.Finally we give its full implementation on FPGA and the performance,experimental and analytical results agree with each other very well.关键词：carrier acquisition algorithm;UQPSK;AFC;PLL2|1532|5更新时间：2025-07-16 - 摘要：Based on the property of Human Vision System(HVS) that human eye's sensitivity to an image varies with different informative regions of the image,Pulse-Coupled Neural Network(PCNN) model is modified for image segmentation.The modified PCNN stimulated by an input image has pulse output with multiple pulse values rather than two,according to the local information rate of the input image.This results in segmentation of the image with respect to local information rate delivered by the image.Experiments on image segmentation with our method and image compression on the segmented images that the lower the information rate is,the higher the compression rate is,show much better performance in both compression rate and subjective perceptual quality of the reconstructed image compared to image segmentation with standard PCNN and image compression with an overall compression rate.关键词：pulse-coupled neural networks;image segmentation;information;image compression2|1226|6更新时间：2025-07-16
- 摘要：A special fourth-order time-average moment spectrum approach is proposed for estimating cubic nonlinear coupling.It can be applied to obtain the coupled and coupling frequencies in mutually correlative any mean multiplicative noise which is independent of additive noise.In the meantime,this method needn't constrain the distribution and color of noise.Lastly,this method is generalized to two-dimensional case.Simulation examples illustrate our algorithms.关键词：multiplicative noise;fourth-order time-average moment spectrum;cubic nonlinear coupling;two-dimensional harmonic2|985|1更新时间：2025-07-16
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