最新刊期
卷 46 ， 期 6 ， 2018
- 摘要：Synchronization clock bias can significantly increase the localization errors.In order to solve this problem,this paper presents theoretical analysis and the improved method.First,the Cramér-Rao bound(CRB) on the parameter estimation is shown in the presence of synchronization clock bias.A more compact CRB expression for the source position estimation is obtained.Based on the maximum likelihood(ML)criterion and the Taylor series(TS) localization method,an analytical expression for the mean square error(MSE) of the source position estimation is also derived when the estimator assumes the clock bias does not exist.Subsequently,the localization method based on dimension-reduction TS iteration is presented and the closed-form ML solution for the clock bias is also given.Finally,numerical experimental results support the validation of the theoretical analysis,and also demonstrate that the proposed method can mitigate the effects of clock bias.330|769|4更新时间：2025-07-08
- 摘要：Phase Locking Value(PLV) is an algorithm describing different signals' correlation (synchronization),which is based on the concept of phase synchronization and its effectiveness has been verified in the field of EEG(Electro Encephalo Graphy).Aiming at the issue of extracting EEG signal's feature in the current lie detection method,this study applied PLV to the field of EEG of lie detection for the first time.We find lying cognitive mechanism with the correlation between different brain regions under lying cerebration,and use support vector machine (SVM) to execute pattern recognition between liars and honest' signal utilizing the correlation as a feature.The result of classificationaccuracy is 88.50%.Therefore,the proposed method verified that the application of PLV in lie detection is effective and it provided a new way to EEG lie detection signal.关键词：lie detection;phase locking value (PLV);EEG;support vector machine229|920|4更新时间：2025-07-08
- 摘要：Authenticated encryption,as a symmetric cryptographic primitive,can protect privacy and integrity simultaneously,which plays an important role in information security.Most of the existing authenticated encryption algorithms are designed based on the working mode of block cipher,which needs to call full round of block cipher.Thus the efficiency is quite limited.This paper considers to construct an efficient authenticated encryption algorithm dedicatedly using basic components.We first present a general structure by combining Chinese block cipher standard SM4 and the general Feistel structure.With the mixed integer linear programming (MILP) method,we find several secure structures against the collision attacks with different sate size and efficiency,which can be used as building blocks for MACs and authenticated encryption.Then we design an authenticated encryption using the structure with good state size and efficiency,and give the corresponding security analysis and implemention.Our benchmarks show that it runs about 10 times faster than SM4-GCM.关键词：authenticated encryption;design;general Feistel structure;MILP;SM4 cipher;SM4-GCM165|1555|4更新时间：2025-07-08
- 摘要：The status of current various swarm intelligence algorithms contains many strategies which cover their core issues,therefore,a new swarm intelligence algorithm by simulating sheep behaviors optimization (SO) is devised.Based on the core of swarm intelligence algorithms,SO designs three kinds of strategies,namely global exploration,local exploitation and escaping from local optimization,by simulating three different kinds of corresponding sheep behaviors,namely bellwether guidance,moving to each other,and shepherd dog supervision respectively.The experimental results of benchmark test functions demonstrate that,compared with particle swarm optimization,SO gets better solution,faster convergence speed and better stability.关键词：swarm intelligence;test function;global exploration;local exploitation284|1040|1更新时间：2025-07-08
- 摘要：Digital photography visiometer systems have been well developed and widely used in visibility observation at daytime.However,the observation at nighttime is often limited due to errors and fluctuations associated with the poor uniformity of illumination and instability of lighting-sources at nighttime which might be affected by power-supply sources and environmental temperature changes.In this study,we proposed a specific light-emitting-diode (LED) system as nighttime lighting-source which is anti-shaking,stable,and has a short response time.The uniformity of illumination has been significantly improved by using these high-density arrays of LED lighting sources with four illumination reflectors installed around the LED lighting-source box and one diffuser in the front.To reduce the fluctuations and improve the stability of the power-supply system,we designed a high-stable power supply system with constant-voltage-drive mode and constant self-feedback current drive circuit.Target-oriented algorithms have been developed to minimize the errors due to changes in illumination of lighting sources caused by temperature changes.关键词：visibility;LED;nighttime observation;uniformity;instability100|709|5更新时间：2025-07-08
- 摘要：An image segmentation method based on robust regional constraint FCM (Fuzzy C-Means) is proposed,which combines hidden Markov random filed (HMRF) model with FCM.In order to improve the performance of the proposed method,the consistency of superpixels of the input image is adaptively used as a priori in clustering process.The proposed method first obtains the superpixels of the image,and for each superpixel,calculates a contribution of each pixel to the superpixel and the contributions are used to compute the superpixel's membership functions.And then the pointwise prior probabilities of pixels are calculated with pixel-level membership function or region-level membership function according to whether the superpixel to which the pixels belong has the dominant label.The use of region-level membership function is to guide the direction of clustering optimization,and thus there are some unused labels which are removed in the iteration process.Finally,the segmentation result is obtained after iteration stop.Experimental results demonstrate the good performance of the proposed method.关键词：image segmentation;fuzzy clustering;super pixels;dominant label;region constraint357|676|5更新时间：2025-07-08
- 摘要：Automatic segmentation of pulmonary fissures is a nontrivial task in CT(Computer Tomography) chest images,due to incomplete,disrupted,deformed and accessory fissures.In this paper,we present a approach to fuse pulmonary structure characteristics for fissure segmentation.Firstly,we fuse the prior knowledge of trachea and pulmonary arteries to identify fissure region of interest.Then fissures directional field is exploited to enhance fissures and a multi-plane filter is proposed to remove noise for fissure pre-segmentation.Finally fissure region of interest and fissure pre-segmentation are combined for fissure segmentation.Compared with manual fissure references,our method obtained a high segmentation accuracy with median F1-score of 0.881 and 0.878 for the left and right lung images respectively.关键词：automatic segmentation of pulmonary fissures;fissure region of interest;fissure pre-segmentation;multi-plane filter219|1063|2更新时间：2025-07-08
- 摘要：In order to solve the problem that the traditional correlation coefficients between hesitant fuzzy sets are not conform to the statistics and the random process intuition,considering the more precise definition of correlation coefficient in mathematics we point out the drawbacks of the existing correlation coefficients and propose two correlation coefficient methods between hesitant fuzzy sets based on the variance and covariance of them.Meanwhile taking the attribute weight into account,we further extend the correlation coefficients into the weight correlation coefficients and apply them in multi-sensor decision-making problem.The validity of the proposed correlation coefficients to the decision making is illustrated in the simulation example and the capability of the two correlation coefficients as well as the influence of the attribute weight are also compared.关键词：correlation coefficients;hesitant fuzzy sets(HFS);multi-attribute decision making;weight173|763|6更新时间：2025-07-08
- 摘要：This paper presents a fast algorithm of the near-field-error correction in radio frequency simulation system.A simulated direction can be expressed based on the mass center formula and the feed parameters of three-unit.The iterative convergence for the real direction of the target can be replaced by the convergence for the simulated direction,and the latter can be calculated by the differential formula of the mass center.The algorithm based on the differential formula of the mass center can converge quickly.Compared with the traditional method,the used iteration formulas are simpler and feasible for various kinds of radar systems.The conclusions are verified by the numerical simulation.关键词：radio frequency simulation;near-field-error correction;differential formula of the mass center96|587|3更新时间：2025-07-08
- 摘要：Recently,inspired by the migratory behavior of monarch butterflies in nature,a swarm intelligence optimization algorithm,called monarch butterfly optimization algorithm (MBO),is proposed.Since MBO is proposed,it has good performances in various real-world optimization problems.However,migration operator of MBO selects randomly two individuals to generate new offspring,in which the useful search experience of global optimal individual is easily lost.Based on the intrinsic mechanism of the search process of MBO and the character of differential mutation operator,MBO is combined with 7 kinds of DE mutation strategies,respectively.Then a series of experiments are conducted to verify their performance.A DEMBO based on MBO and better differential evolution mutation strategy is presented,in which migration operator is replaced by differential mutation operator to enhance its global optimization ability.The over-all performance of DEMBO is verified and analyzed by 30 typical discounted {0-1} knapsack problem (D {0-1} KP) instances.The experimental results demonstrate that DEMBO can significantly improve the solution quality and convergence speed under the condition of not increasing the time complexity.Meanwhile,the approximation ratio of all the D {0-1} KP instances obtained by DEMBO is close to 1.0.关键词：discounted {0-1} knapsack problem;differential evolution;monarch butterfly optimization algorithm;greedy repair strategy;approximate ratio249|1153|12更新时间：2025-07-08
- 摘要：WLAN indoor localization has caught significantly wide attention.In offline phase,the location fingerprint RSS data acquisition often results in blindness and unreliability,and ignores the relations between the required RSS sample capacity and localization performance.To solve this problem,a new T-test based sample capacity optimization approach for WLAN indoor localization is proposed.In offline phase,the Operating Characteristics (OC) function is used to optimize the allowable minimum RSS sample capacity for the fingerprint database construction.In online phase,we perform the rough localization by using the T-test approach,and then propose the T-test based KNN algorithm for the fine localization of target terminal.This method uses a limited sample capacity to obtain a more stable localization performance analysis results,significantly reducing the amount of manpower and time overhead.关键词：indoor localization;sample capacity;T-test;OC function;K-nearest neighbor184|569|1更新时间：2025-07-08
- 摘要：This paper proposes a weighted two-box model to solve the behavior modeling and distortion compensation problem of broadband RF power amplifier.The model,including the memoryless sub-model and memory sub-model,is used to model the static nonlinear and dynamic nonlinear of broadband power amplifiers.First of all,the input signal amplitude is compressed in weighted memoryless sub-model,which can effectively reduce the fitting error of the static distortion model.And the output value of the sub model is decompressed to ensure the saturation driving performance of the amplifier.Second,the weight memory sub-model is constructed,and is used to adjust the low and high power dynamic distortion sub model dynamically based on the weight function related to signal amplitude.The experimental results show that under different signal driving conditions,the proposed method can reduce the computational complexity while maintain better modeling accuracy and distortion compensation capability.关键词：power amplifier;behavioral modeling;distortion compensation;digital pre-distortion;memory polynomial105|816|0更新时间：2025-07-08
- 摘要：The efficiency of software fault localization may be affected by many factors,such as the prioritization of test case,the structure of test case,the coverage of test case and coincidental correctness test case etc.This paper focuses on the impact of the efficiency of calculation formula by coincidental correctness test cases.For this,we put forward a theoretical analysis framework based on function monotonicity to prove the validity of 30 classical calculation formulas by coincidental correctness.It is a useful theoretical exploration that the efficiency of calculation formula is affected by coincidental correctness.关键词：software debugging;fault localization;coincidental correctness;theoretical analysis162|673|0更新时间：2025-07-08
- 摘要：Aiming at high dimensional bearings-only multi-target tracking,unscented particle PHD based on new sampling rule (NSRUP-PHD) is proposed.For NSRUP-PHD,a particle filter based on unscented transform is designed,which successfully fulfills the states estimation of non-linear system,and realizes the noise update by mixture of a series of Gauss parts.Besides,NSRUP-PHD provides a new sampling method to accomplish the particles angular resolution with the three cubature rule (CR),and the distance between the certain particle and the expectation is the upper limit of probability integration,certainly,the particles can be spread through the whole sampling space by obtaining the relative probability and getting the distance,which results in enhancing the particles efficiency.Simulation results on NSRUP-PHD prove that new filter and sampling method are more effective for bearings-only multi-target tracking in comparison with traditional filter and pseudo random sampling.关键词：multi-target tracking;probability hypothesis density;unscented transform;three cubature rule100|632|1更新时间：2025-07-08
- 摘要：The existing localization methods for an aerial moving target based on satellites are too complex and costly to be used in practical applications.A new localization technology based on two satellites for an aerial moving target is proposed.By combining two localization parameters named time difference of arrival (TDOA) between two satellites and direction of arrival (DOA) from the main satellite,the three-dimensional locations of an aerial moving target can be achieved.The three-dimensional mathematical localization model for an aerial moving target is established with the vector solution method.Moreover,for Monte Carlo analysis,the localization error model is established in consideration of many error factors.Lastly,the proposed localization technology is used in the suppositional scene which is composed of space station and one small satellite,and the numerical simulation is carried out.The simulation results show that the proposed localization technology can realize accurate estimation of the ground track and the three-dimensional position for an aerial moving target.关键词：dual-satellite localization technology;aerial moving target;time difference of arrival;direction of arrival245|450|4更新时间：2025-07-08
- 摘要：This paper presents a robust and high-resolution 2D DOA (Direction of Arrival) algorithm in the field of wireless communication such as radar and sonar,solving the problem that IAA (Iterative Adaptive Aproach) fails to provide reliable DOA estimation performance in impulsive noise environment.In the algorithm,we replace WLS (Weighted Least Squares) with least p order norm (lp-norm) as the cost function.Furthermore,to decrease the complexity of the proposed method,a fast implementation of 2D lp-IAA is also developed based on simplifying the calculation of inverse TBT (Toeplitz-Block-Toeplitz) matrix and fast Fourier transform.Simulation results indicate that,under the condition of low GSNR (Generalized Signal-to-Noise Ratio) SαS distributed noise with single snapshot,2D lp-IAA algorithm performs better in distinguishing adjacent multi-target signals than CRCO-MUSIC (CoRrentropy based COrrelation-MUltiple Signal Classification) and MUSIC-FLOM (MUltiple Signal Classification-Fractional Lower-Order Moment).Moreover,the average computation time of the fast method is reduced to nearly 1/40 of the lp-IAA algorithm.关键词：impulsive noise;SαS distributed noise;DOA;robust algorithm;high resolution;Toeplitz-Block-Toeplitz;least p order norm220|632|3更新时间：2025-07-08
- 摘要：Automatic modulation recognition and parameter identification of orthogonal frequency division multiplexing (OFDM) play a vital role in the field of non-cooperative communication applications.A blind recognition and parameter identification called generalized cyclostationarity algorithm is proposed for OFDM in alpha stable distribution noise.Firstly,the received signal is mapped by nonlinear transformation,the analytical expressions for the generalized cyclic autocorrelation function are derived,and the generalized cyclostationarity characteristics of single carrier linear digital (SCLD) modulations and OFDM are investigated.Then,the recognition feature is structured based on generalized cyclic autocorrelation function to recognize OFDM versus SCLD signals.Finally,for the problem of blind parameter identification for OFDM,an algorithm based on generalized cyclic autocorrelation function is presented.Theoretical analysis and simulation results demonstrate the effectiveness of the proposed algorithm in alpha stable distribution noise.Furthermore,this algorithm obviates the need for signal preprocessing tasks,such as symbol timing estimation,carrier and waveform recovery.156|617|5更新时间：2025-07-08
- 摘要：The combination of full-duplex(FD)communication and two-way relaying(TWR)provides higher spectral efficiency,but the decoding reliability is worsen by residual self-interference(RSI).The error performance of non-orthogonal FD-TWR is investigated.With the assumption that the relay has more efficient self-interference cancellation than the user nodes,the diversity and coding gains are derived with the help of the approximate expression of pair-wise error probability in the high transmission power region.Based on the coding structure,the achievability of the diversity gain is analyzed.Compared with the half-duplex TWR system with the same spectral efficiency,the FD-TWR system with suppressed RSI and full-diversity precoder has the superiority of 20dB on the error performance at the bit error rate of 10-3.关键词：full-duplex;two-way relaying;residual self-interference;pair-wise error probability;full-diversity precoding;cooperative communication175|450|1更新时间：2025-07-08
- 摘要：Aiming at the problem of weak robustness and poor accuracy of the traditional multi-function radar (MFR) state prediction methods,a MFR state prediction method aided by maneuvering features is proposed.First of all,the aircraft maneuver features and the conventional reconnaissance parameters work together as the prediction feature set;then,on the one hand,the conventional prediction model can be achieved by support vector regression (SVR) and detected signal feature set;on the other hand,the MFR state transition probability model of each state is obtained by SVR and maneuvering feature set;at last,the eventual prediction state is obtained by the D-S evidence theory.Experimental results show that in comparison with SVR and LSR,the proposed method improves the average prediction accuracy by 6.97% and 7.2% respectively,and meanwhile,it is more robust.The proposed method can be applied to the mechanical equipment,road transport,etc.by further extension.关键词：Multi-function radar;state prediction;support vector regression;aircraft maneuvering features;D-S evidence theory142|501|3更新时间：2025-07-08
- 摘要：It is difficult for the existing natural language processing algorithms to model the time and authority of short texts such as paper titles of scientific literature.Besides,the short texts always tend to have fewer words and thus suffer from high dimension and sparsity.A keyword extraction method involving both real-time and authoritativeness is presented.A weighted hyper-graph is constructed where vertexes represent weighted terms and weighted hyper-edges measure the semantic relatedness of both binary relations and nary relations among terms.On one hand,the source of the documents,the year of publication and number of citations are considered for weighting hyper-edges,on the other hand,the degree of association between the nodes and co-occurrence distance for each pair of nodes in particular title are calculated for weighting hyper-vertexes.The random walk approach is performed on the weighted hyper-graph to obtain the recommended keywords.Experimental results demonstrated that compared with three baseline algorithms,the proposed approach is able to extract keywords with higher precision and recall.关键词：weighted hypergraph;weighting strategy;keywords extraction;random walk;natural language processing;data mining238|770|5更新时间：2025-07-08
- 摘要：Vortex beam heating is a research hotspot in ionospheric heating experimental technique.The existing research work focuses on the analysis and interpretation of experimental phenomena,while there are few discussions about the array feeding design method.Based on the Fresnel diffraction theory,the analytical expression of propagation characteristics of vortex beam in free space is deduced,as the inspection basis for the array feeding design method in the vortex heating mode.According to the Helmholtz equation of magnetic vector potential,the calculation formula of array feeding distribution for arbitrary order Laguerre-Gaussian vortex beam is derived.Then the formula is verified by the results of the existing literature.This provides the theoretical guidance for the array feeding design.By introducing the concept of sparse array,a design method of array feeding is presented,which is simple,convenient,practical and can be applied to any planar array.Simulation results demonstrate the effectiveness of the method.关键词：vortex beam;Fresnel diffraction;Helmholtz equation;sparse array116|676|0更新时间：2025-07-08
- 摘要：With the increasing threat of extremely difficult environment of communication system,the electromagnetic pulse protection module which has the characteristics of high power capacity,high isolation,low insertion loss and fast response time is becoming increasingly important.In this paper,the principle of radio frequency limiting of PIN is studied,and the structure of passive multistage PIN diode is adopted.Through the establishment of its field simulation model,the corresponding S parameters are extracted,and the optimal matching network is optimized.The electromagnetic pulse protection module which works at 0~200MHz has insertion loss of less than 0.15dB,the voltage standing wave ratio (VSWR) of less than 1.4,response time of less than 1ns is designed.Combined with self-built PIN diode model,ADS simulation software is used to simulate the limiting performance of electromagnetic pulse protection module.The result shows that all the indexes meet the requirements.关键词：PIN diode;limiter;ADS;insertion loss126|923|2更新时间：2025-07-08
- 摘要：To precisely analyze the quick status transformation and continuous confrontation in network,the security status transformation model is formulated to analyze the transformation of network security status,referring to the infectious disease dynamics.Based on the mentioned above,the attack-defense differential game model is formulated in the paper.Then saddle point strategies of the game model are figured out,through which the algorithm of optimal defense strategies selection in the consistent confrontation is given,which could help make optimal defense decision in dynamic and continuous attack-defense confrontation.Finally,the experimental results show model and method proposed in this paper are valid,and some instructive conclusions on network defense are drawn by the experimental analysis.关键词：network security;network attack and defense;security status transformation;game theory;differential game;network defense;attack-defense analysis;optimal strategies selection213|1038|5更新时间：2025-07-08
- 摘要：Natural scene text detection is an important task for image analysis and understanding.In this paper,a natural scene text detection method is proposed,using adaptive color clustering and context information analysis.Firstly,combining hierarchical clustering with self-learning strategy,we design an adaptive color clustering method,which learns clustering weights automatically and generates high character recall.Then,considering text in images usually containing several characters,we propose a character verification strategy based on image context information,which can guarantee high character recall and remove non-text components at the same time.Finally,characters are merged to text lines,and further post-processing is applied to generate final text detection results.Experiments on the ICDAR2013 publicly available dataset show that we obtain recall of 74.17%,precision of 83.40% and F-score of 78.52%.Compared with other text detection methods,our method obtains better text detection performance,indicating superiority of the proposed method.关键词：natural scene text detection;adaptive color clustering;context information;self-learning strategy98|654|2更新时间：2025-07-08
- 摘要：Noise and streak artifacts are serious in low-dose CT (LDCT) images of lung,especially for the top and bottom layers.To improve the quality of LDCT sequential images,we proposed a method to remove noise and streak artifacts by using a joint structural dictionary.Firstly,according to the gray-scale features of lung CT image,we divided high resolution CT (HRCT) images into four groups,and obtained four dictionaries for each group by dictionary training.Secondly,computed the information entropy and the histogram of oriented gradient (HOG) of each dictionary atom.And then obtained the structure dictionary of corresponding group by feature clustering.Finally,the joint structural dictionary can be obtained by combining these four structure dictionaries.On the basis of non-local mean filtering for LDCT images,the joint structural dictionary is used as a global dictionary to get the denoised image by sparse representation and reconstruction.In order to validate the effectiveness of the proposed method,simulated and clinical LDCT data are used.Compared with reported methods (KSVD,AS-LNLM and BF-MCA),our method performed better in denoising,streak artifact-removing and details-preserving for the whole LDCT scans,especially for the top and bottom layers.The proposed algorithm can significantly improve the quality of lung LDCT images.关键词：low-dose lung CT image;joint dictionary;sparse representation;image denoising81|670|2更新时间：2025-07-08
- 摘要：A blind recognition method of channel coding based on soft information was proposed for packet interleaver and convolution code in a non-cooperative digital communication system.The method builds conformity degree concept using the soft information.It identifies the row number of interleaving matrix and the parity-check vector of convolution code by using the total conformity degree of the sample sequence.And the row coordinate of starting point is identified by the change rule of average conformity degree of each sampling sequence.Finally,the column number of interleaving matrix and the column coordinate of starting point are recognized according to the conformity degree of de-interleaved data.Simulation results show that the proposed method provides an optimal performance in the noisy environment,and has 5dB SNR gain when achieving the relatively high accuracy compared with the recognition algorithm based on hard information.关键词：non-cooperative digital communication system;packet interleaver;convolution code;blind recognition;soft information;channel coding223|498|3更新时间：2025-07-08
- 摘要：Embryonic bio-inspired hardware technology provides a new idea for designing large scale integrated circuit with high reliability.In the bus-based embryonic electronic cell array (BEECA) with determined scales,an idle cells optimum selection method is proposed,which finds a balance between hardware resource consumption and reliability.Based on the multi-state system reliability theory,a universal generating function (UGF) is used to establish BEECA reliability model.The consumed number of MOS (Metal Oxide Semiconductor) transistors is used to measure BEECA hardware resource consumption,and BEECA hardware resource consumption model is established.Based on the established reliability model and hardware resource consumption model,the unoccupied cell number in the array is selected under the constraints of the design.The simulation experiment and analysis indicate that the proposed design can optimize the selection,and in the meanwhile the selection can avoid the dependence on the experiences.关键词：embryonic electronic;bus;idle cells;fault repair;hardware resource consumption;reliability;multi-state system141|562|2更新时间：2025-07-08
- 摘要：Accurate estimation of the angle of arrival (AOA) of the signal provides the possibility of high precision indoor positioning,in order to achieve the accurate AOA and extract the AOA information of the direct path to locate the target,this paper presents a sub-meter indoor localization system that uses the channel frequency response (CFR) to expand the array antenna.Firstly,this paper collects the CFR information to estimate the AOA and time of arrival (TOA) of Wi-Fi signal.Secondly,this paper presents a direct path identification algorithm based on the two-dimensional clustering information of AOA and TOA.In addition,this paper proposes a line of sight (LOS) environment and non line of sight (NLOS) environment recognition algorithm to distinguish whether the current receiver is in the LOS or NLOS environment relative the transmitter.Finally,this paper uses the existing Wi-Fi devices with three antennas to measure the angle and positioning in the indoor room.The experimental results show that the proposed positioning system can achieve a median error of 0.8 m and 1.3 m respectively in the LOS and NLOS environment,and can be used for high precision indoor positioning.关键词：Wi-Fi;indoor localization;channel frequency response (CFR);angle of arrival (AOA)480|1282|3更新时间：2025-07-08
- 摘要：To address track-to-track association problem for aircraft platforms in complex condition,where targets are distributed closely,sensor biases are time-varied,and different sensors report different targets,an anti-bias track-to-track association algorithm based on distance hierarchical clustering is proposed according to the statistical characteristics of Gaussian random vectors.Equivalent measurement equation for moving platform is firstly derived,linear relationship between state estimates and real states,sensor biases,measurement errors is established based on Taylor series expansion,distance vector is obtained based on real state cancellation,and homologous tracks are extracted based on distance vectors hierarchical clustering.Adaptability experiments are established based on three factors including different targets densities,random errors and sensor biases.Monte Carlo simulations demonstrate significant improvements of association accuracy and complex condition adaptability of the proposed algorithm compared with the classical algorithm based on the reference topology feature (RET).关键词：track-to-track association;time-varied sensor biases;equivalent measurement equation;distance vectors;hierarchical clustering188|488|5更新时间：2025-07-08
- 摘要：Although the dual mode blind equalization algorithm based on constant modulus and decision directed (DD) criterion can significantly improve the performance of equalization,the dual mode blind equalization algorithms at present need to set up the switching parameters which lack of theoretical basis.To solve the problem that the switching parameters are difficult to be determined in the dual mode blind equalization algorithm,a new dual mode blind equalization algorithm with combination cost function is proposed.The combination cost function is obtained by using the weighted constant modulus and DD cost function,and the weight is adaptively adjusted during the blind equalizer update process to switch from constant modulus algorithm (CMA) to DD algorithm,which avoids the design of the switching parameters in the dual mode algorithm,and the generalization performance can be improved.To overcome the shortcoming of phase blindness of CMA,the proposed algorithm is optimized based on modified CMA (MCMA),which can further improve the convergence performance.The simulation results show that the proposed dual mode blind equalization algorithm can take full advantages of CMA and DD algorithm,which has faster convergence rate and lower steady state error.关键词：blind equalization;CMA;DD algorithm;dual mode algorithm82|619|0更新时间：2025-07-08
- 摘要：To solve the problem of poor load balancing performance and difficult path deployment in the traditional networks,a SRMFT(Segment Routing based Multipath Flow Transmission) mechanism is designed,which utilizes the centralized control advantage of software-defined networking.Firstly,the SRMFT optimization model is set up to achieve the co-optimal scheduling of the data stream.Secondly,the multi-path flow scheduling problem is transformed into the simplest SIDs(Segment IDentify sequence) selection problem with segmented routing algorithm and the simplest SIDs generation algorithm.And the traffic flow scheduling algorithm is proposed.Finally,experimental results show that,under the same network traffic model,compared with the typical multi-path streaming mechanism,SRMFT effectively improves the bisection bandwidth of networks,reduces the transmission delay of short stream,and also have a lower flow table storage overhead.关键词：segment routing;software defined networking;multipath flow;load balance;data center294|1098|4更新时间：2025-07-08
- 摘要：The integration and detection performance for the maneuvering targets may slide down due to the defocusing effects of the range migration and the Doppler frequency migration in the long integration time.To address these issues,we propose a fast non-searching method based on frequency axis reversal and generalized autocorrelation function.In this algorithm,the frequency axis reversal transform is applied to correct the range migration in the range frequency domain.Then the received signal becomes cubic phase signal and both generalized autocorrelation function and generalized scaled Fourier transform (GSCFT) are applied to finish the signal reduction and the estimation of the moving target.Finally,estimated parameters are employed to dechirp the echo and the target is well focused in the range-Doppler domain.Compared with the existing methods such as Keystone,GRFT (Generalized Radon Fourier Transform),RLVD (Radon-Lv's Distribution) and RFRFT (Radon Fractional Fourier Transform),the presented algorithm can fast eliminate the range migration and obtain the motion parameters without any searching procedure and can achieve a good balance between the computational cost and the detection ability.Several simulation experiments are provided to demonstrate the effectiveness of the proposed algorithm.关键词：maneuvering target detection;motion parameters estimation;cubic phase signal;frequency axis reversal transform246|442|2更新时间：2025-07-08
- 摘要：Most research of network security based on the traditional game theory use completely rational assumption.For the condition of bounded rationality and the characteristic of dynamic changing process,we combined the evolutionary game model with Markov decision-making process based on the theory of non-cooperative evolutionary game,which is on the restraint of bounded rationality.Thus we constructed a multi-stage Markov attack-defense evolutionary game model to achieve multi-stage and multi-state dynamic analysis and evolution.Besides,on the basis of the sum discount payoffs to design objective function,the method to solve the evolutionary stable equilibrium was proposed,and the optimal defense strategy selection algorithm was provided.Finally,the validity of the model and method is validated by numerical simulation.关键词：network security;network attack-defense;game theory;bounded rationality;evolutionary game;network defense;Markov decision-making;multi-stage optimal defense272|619|6更新时间：2025-07-08
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Blind SNR Estimation of Time-Frequency Overlapped OFDM Signals for Underlay Cognitive Radio Networks
摘要：In this paper,we propose one cyclic autocorrelation function (CAF) based method to implement the blind signal-to-noise (SNR) estimation over the underlay cognitive radio networks.The orthogonal frequency division multiplexing (OFDM) is adopted here.This SNR estimator utilizes the discrete spectrum of the CAF for the received signals,whose time delay and cyclic frequency are zero.Numerical results show that the proposed method is robust to the power ratio and spectral overlapping of the composite signal without prior information.Moreover,when the SNR is greater than -7dB,the mean square error (MSE) for the SNR estimation is less than 0.1.关键词：cognitive radio;parameter estimation;underlay;time-frequency overlapped;OFDM;SNR166|549|1更新时间：2025-07-08 - 摘要：A resonant DC link current-source zero-voltage switching PWM rectifier is put forward to solve the switching loss problem under high switching frequency.The auxiliary circuit is in parallel with the DC bus and is added in the DC link.Only one auxiliary switch set in its auxiliary circuit.In the process of commutation,zero-voltage switching can be achieved in the main switch and zero-current switching can be achieved in the auxiliary switch.Furthermore,when multilevel PWM control strategy is adopted by the rectifier,the auxiliary circuit only needs to work for one time in each switching period.This paper analyzed the resonant commutation process.The simulation results show that the characteristics of the simulation waveforms are consistent with the theoretical analysis,the switches can realize soft-switching and the rectifier can run stably.The current-source energy-saving rectifier with zero-voltage switching can be operated under high switching frequency and high power applications.关键词：rectifier;auxiliary resonant circuit;zero-voltage switching;energy-saving127|611|3更新时间：2025-07-08
- 摘要：High-performance decimal hardware arithmetic is now a high demand due to the requirement for accurate computation in fields like commercial computing and financial analysis.The performance of fully redundant decimal multiplier is limited because the circuit for fully redundant adder is complex.A modified fully redundant adder based on overloaded decimal digit set (ODDS) and a new decimal reduction tree based on fully redundant ODDS adders are proposed.The signed-digit radix-10 recoding and redundant binary coded decimal (BCD) codes are used for fast partial product generation.A recoding conversion circuit is proposed to generate BCD-8421 product fast.Comparison shows that the delay and area of the proposed decimal multiplier are small.关键词：multiplier;decimal arithmetic;BCD coding;redundant coding;fully redundant adder;recoding conversion150|733|1更新时间：2025-07-08
- 摘要：In modeling ship magnetic field with hybrid model,the dipole array location distribution and the authenticity of the measurement data,which affects model accuracy and stability,should be considered.The paper takes the condition number of the coefficient matrices of the hybrid model as the objective function,gets the optimal position distribution of magnetic dipole arrays by optimizing the matrix condition number with simulated annealing algorithm,optimizes the measurement data by eliminating the great error in the measurement point,and finally obtains the high precision and stable model of ship magnetic field by using stepwise regression to solve the model equation.The measured data model shows,compared with the model based on the equidistant distribution of magnetic dipole of hybrid model,the model that the proposed method builds has a higher accuracy and is more stable,and the accuracy of the model can reach 96%.This method can be used for high precision modeling of ship magnetic field under complex sea conditions,as well as surface magnetic target detection and positioning system.关键词：ship magnetic field;dipole array location distribution;measurement data;condition number of matrices;simulated annealing algorithm;stepwise regression183|998|13更新时间：2025-07-08
- 摘要：Channel coding technology is widely used in digital wireless communication systems for forward error correction. Channel coding recognition means to reversely recognizing the coding parameters. For blind recognition of convolutional interleavers,the existing method based on the existence of frame sync codes has high computational complexity,and is not able to recognize the depth starting point. The method even fails for certain interleaver and frame length combinations. Its main computation is in recognizing the period of frame sync code in the interleaved sequence. In this paper,a low complexity method which avoids lots of repeated computation is developed for the period recognition. Then,a method called cyclic convolutional de-interleaving is proposed to de-interleave the partitioned-and-summed version of the interleaved sequence,and thus the frame sync code and the interleaver parameters are recovered in the meantime. The proposed methods are able to recognize the whole parameters for any interleaver and frame length combinations. Theoretical and simulation results show that,compared to the existing method,the proposed methods reduce the computational complexity by a percentage ranging from around 50% to more than 90%,and improves robustness against channel noise by more than 2dB,showing high application value in areas like cognitive radio.关键词：wireless communication;cognitive radio;non-cooperative communication;channel coding;blind recognition;convolutional interleaver;frame synchronization230|1007|4更新时间：2025-07-08
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