最新刊期
卷 42 ， 期 6 ， 2014
- 摘要：Considering near-field sources localization, a method based on sparse signal reconstruction is presented. The sparse optimization problem is solved through minimizing L1-norm of sparse signals, and the sources localization is realized. The method uses an estimate of noise power as the tradeoff of the optimization problem, without prior knowledge on noise. To reduce the computational complexity, the two-dimensional positioning problem is transformed into two one-dimensional parameter estimation problems. Simulation results show the performances of the proposed method.关键词：array signal processing;near-field;source localization;sparse representation3|1810|7更新时间：2025-07-16
- 摘要：Prior information can be used to improve detection performance for knowledge aided detectors,but the detection performance may be affected by the mismatches between the prior information and current clutter environment.In this paper,the knowledge aided detector for compound Gaussian clutter with inverse gamma distribution texture is considered,and the formula of false alarm rate and probability of detection for Swerling I target of the detector are derived with prior model mismatches (mismatched parameters of inverse gamma distribution).The quantitative relationship between detection performance and mismatched prior model is obtained.Using two detectors with different parameters for the current clutter environment and assessing the detection performance,the parameters of current clutter environment can be estimated.The results of computer simulation and live data analysis show that,the knowledge aided detector with cognitive method can achieve better detection performance than conventional detectors.关键词：knowledge aided detector;compound Gaussian;inverse gamma distribution;mismatched prior information;cognitive method2|1427|7更新时间：2025-07-16
- 摘要：How to precisely detect electromagnetic spectrum anomaly is a major challenge for radio monitoring and electromagnetic environment evaluation,especially in the condition of complex electromagnetic environment and lack of pre-knowledge information about frequency use.Based on time series analysis theory,a timing model which presents the correlation between the previous and the following sequence of spectrum occupancy,is built to help us realize the autonomous identification and robust estimation of typical spectrum anomaly.The analysis results indicate that,without actually requiring pre-knowledge of frequency database and radio monitoring historical data support,this method can effectively identify the types of spectrum anomaly,occurrence time,anomaly effect intension and other relative information.Furthermore,through the robust estimation of spectrum occupancy model,we can significantly improve the model's fitting performance and raise the adaptability and robustness of the model to external interferences.关键词：spectrum anomaly;autonomous detection;robust estimation;electromagnetic environment2|2224|3更新时间：2025-07-16
- 摘要：Almost all of the existing greedy iterative compressed sensing reconstruction algorithms estimate the signal by the method of least squares,which introduces the measure noise into the signal estimation.Aiming at this problem,a new weakly matching pursuit denoising recovery for compressed sensing based on Kalman filtering is proposed.The new algorithm does not need the sparse prior while it estimates the signal best for each iteration according to the minimum mean-square error criterion by Kalman filtering.Meanwhile,weakly matching pursuit is used to sift the effective support set and pick out the redundancy to recover the original signal.The new algorithm is as effective as other greedy ones and is able to avoid recovery failure due to noise interference or unknown sparsity as well.The theoretical analysis and experimental simulation prove that the performance of the new algorithm is better than that of the existing greedy iterative reconstruction algorithms in the same condition.The operation time of the new algorithm is shorter than that of BPDN and the similar KFCS algorithm.关键词：compressed sensing;denoising;adaptive reconstruction;Kalman filter2|1547|8更新时间：2025-07-16
- 摘要：For the problem of time-delay estimation for Chirp pulse signals,the characteristics of Chirp pulse signals based on the discrete fractional Fourier transform was theoretically derived.When time-delay equivalent frequency parameter was greater than the sampling rate in fractional Fourier domain,the spectrum of Chirp pulse signals in fractional Fourier domain produced aliasing,which caused the delay estimation ambiguity problem.In order to solve this problem,the time-delay estimation of Chirp signal based on double-channel DFRFT cross-spectral method was proposed,then the principles of the two-channel sampling rate selection and the performance analysis was given.The experimental results show that,in a certain sampling rate,the proposed algorithm is able to quickly and accurately estimate the time-delay parameters of Chirp pulse signals.关键词：discrete fractional Fourier transform (DFRFT);cross-spectrum;time delay estimation;Chirp pulse signals2|2|2更新时间：2025-07-16
- 摘要：Long-time coherent integration technique is one of the most important methods for the improvement of radar detection ability of weak moving target.Based on the analysis of range and Doppler migrations of a moving target,a long-time coherent integration method via Radon-fractional Fourier transform (RFRFT) is proposed.The target's observation values in the range-slow time plane are firstly extracted according to the searching area of the preset motion parameters.Then the observation values are matched and accumulated by FRFT and a nonuniformly moving target can be declared by the detection map in the RFRFT domain.The proposed method can compensate the across range unit and Doppler frequency migration effects simultaneously.In addition,the background clutter and noise can be well suppressed,which increases the integration gain.Simulation results show that the proposed method has the ability of detecting weak moving target under strong clutter environment.关键词：moving target detection;across range unit;doppler frequency migration;long-time coherent integration;Radon-fractional Fourier transform (RFRFT)2|2|12更新时间：2025-07-16
- 摘要：For target tracking in the energy and bandwidth-constrained wireless sensor networks,a sensor selection scheme is proposed based on quantized data and conditional posterior Cramér-Rao lower bounds (CPCRLB).The received measurements are quantized and compressed to save the energy and bandwidth.The CPCRLB with quantized data is derived and used as the criterion for sensor selection to optimize the performance of tracking.Moreover,the particle filtering is employed to compute the CPCRLB approximately.The CPCRLB based sensor selection scheme is compared with the mutual information and the unconditional posterior Cramér-Rao lower bounds based sensor selection schemes by simulation.The results show that the CPCRLB is more efficient and the improved performance is achieved.2|2|6更新时间：2025-07-16
- 摘要：The method of SP-FDTD(Splitting Plane wave Finite Difference Time Domain)is applied to 3D FDTD(Finite Difference Time Domain)method for plane wave incidence.Based on the split-field formulation,the method has the new iterative equations and can eliminate the error of interpolation and discretized phase velocity mismatch between 1D FDTD and 3D FDTD grid.Numerical results show that the present method is valid for different type of wave sources,and accuracy for oblique incident plane wave,with the leakage error on the order of -300dB.关键词：SP-FDTD method;split-field;plane wave3|4|3更新时间：2025-07-16
- 摘要：Transcutaneous energy transmission has been widely used for the power supply of the implantable medical devices.The most important study on the transcutaneous energy transmission is about how to improve its transfer efficiency and distance.Based on the analysis of the mutual inductance coupling theory,and combining with the characteristics of the strongly coupled magnetic resonances,this paper proposed a three-coil coupling structure which is more suitable for transcutaneous energy transmission.The theoretical analysis indicates that the proposed three-coil coupling structure strengthens the coupling efficiency when the coupling coefficient is less than 0.25 and nearly doubles the efficiency when the coefficient is 0.04.The experimental results verified the theoretical analysis.关键词：three-coil coupling;transcutaneous energy transmission;implantable medical device2|2|0更新时间：2025-07-16
- 摘要：In order to meet the special requirements of virtual enterprises (VE),this paper proposed an efficient generalized inter-enterprise authentication scheme.The scheme employed the elliptic curve threshold signature algorithm and the variable multi-party protocols to realize efficient cross certifications between VE partners through a virtual bridge CA.Analysis shows that the proposed scheme can provide a flexible distributed trust policy for VE,and has the advantages of low computation and communication cost,high bit-security,short certificate-chains,and adaptability to various structures of VE,so it can better satisfy the special requirements of inter-enterprise authentication in VE,especially when the computation and communication resource is constrained.关键词：virtual enterprise (VE);inter-enterprise authentication;virtual bridge certificate authority (VBCA);elliptic curve cryptosystem (ECC);threshold signature2|2|8更新时间：2025-07-16
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Wideband Differential-Mode Current Injection Testing Technology Based on Directional Coupling Device
摘要：This paper presents a kind of differential-mode current injection testing technology.The equal response voltage on the equipment port was regarded as equivalent principle.The injection and radiation response analysis model and the injection voltage source extrapolation model were established.The conditions of using injection as a substitute for radiation were determined.Moreover,this paper discussed the implementation technology of differential-mode current injection.The function and structure design scheme of the auxiliary test equipment was proposed.The equivalent relation between injected voltage and radiated field was derived.On the basis of the above,the differential-mode current injection test method was summarized.Finally,the test results of typical RF front-end system verify the validity of the proposed method.关键词：HIRF;differential-mode current injection;linear extrapolation;directional coupling device;equivalent source wave2|2|1更新时间：2025-07-16 - 摘要：Compared to the traditional Fuzz testing,dynamic test generation can improve the efficiency of software testing and vulnerability analysis. This paper focuses on the performance of path covering and constraint solving in dynamic test generation,and proposes a method which constructs loop summary with induce variables and abstracts loop summary by symbolic computation. This paper uses the loop summary in software dynamic analysis,and proves that the loop summary can improve the efficiency of loop constraint solving and loop path traversal.关键词：loop;software testing;vulnerability analysis;symbol computation3|4|2更新时间：2025-07-16
- 摘要：Link scheduling technology plays an important role in improving data transmission reliability in wireless sensor networks.Traditional link scheduling algorithms mainly focus on how to find the minimum scheduling frame under the condition of interference-free transmission,but ignore the impact of route selection on link scheduling,which leads to an expansion of interference set for some links and reduces the slot reusability.In response to this problem,the relationship between link scheduling,route selection and energy consumption is analyzed systematically,and an energy-efficient link scheduling model combined with routing optimization is presented.Through variables deletion and model transformation,an optimal routing tree construction algorithm is proposed to accelerate the solution speed based on integer programming.Furthermore,according to the routing tree and link demands achieved by integer programming,a heuristic slot allocation algorithm is proposed based on maximum degree of interference,to minimize the scheduling period.Extensive simulation results are presented to demonstrate the effectiveness of our proposed algorithm.关键词：wireless sensor network;link scheduling;routing tree;integer programming2|2|3更新时间：2025-07-16
- 摘要：To solve the problems of complex blind source separation in the condition of time-varying numbers of source,a dynamic number estimation method for complex-valued source based on cross-validation technique was proposed.In this method,an adaptive complex blind source separation algorithm based on kurtosis of complex source is derived by using a Newton update method.Due to the innovative complex blind separation algorithm without any restrictions or constraints on source signals,it can be used to separate sub-and sup-Gaussian sources with canonical or noncanonical distribution.The effectiveness of the proposed methods was validated by simulation of time-varying numbers of complex source.Based on the experimental result,an estimation method of dynamic direction of arrival (DOA) was proposed to online estimate DOA orientation under the case that the number of sources is unknown in advance and time-varying.关键词：complex blind source separation;cross validation;Newton update algorithm;kurtosis;adaptive2|3|1更新时间：2025-07-16
- 摘要：In case of the limited communication capacities of the nodes in the realistic decentralized networks,a consensus-based auction approaches(CDACA)was proposed to achieve the optimal multi-assignment for multiple spectrum.Based on local information,each secondary user conducts an ascending-bid auction for a single channel in CDACA forward auction phase,and primary users with unassigned channels conduct descending-bid auction for their favorite secondary users in reverse auction phase;both secondary users and primary users use consensus routine based on local communication as the conflict resolution mechanism to achieve agreement on the winning bid values.Theory analysis proves CDACA always converges to an assignment that maximizes the total network benefits within finite number of iterations,even for nodes in realistic decentralized networks with limited communication and local outdated information;the algorithm convergence is also proved in dynamic decentralized networks.Under different network topologies in the simulation,CDACA is shown to be superior on convergence speed and spectrum efficiency.4|2|4更新时间：2025-07-16
- 摘要：This paper analyzes the impact on the average data transmission time of primary user (PU) and secondary users (SU),which is caused by the one kind of false alarm event and three kinds of undetected events in realistic cognitive radio (CR) environment.Based on the analysis,the M/G/1 queue model is rectified and the M/G/1-R queue model is obtained,in which the first moment and the second moment of data transmission time of PU and SU are derived.And a multi-priority bubble-queuing access scheme (B-M/G/1-R) based on systemic cost is proposed whose sorting method can minimize the systemic cost.Analytical results and simulation confirm the validity of M/G/1-R model.Also in realistic CR environment,B-M/G/1-R presents the smallest systemic cost and SU data transmission interrupted times.关键词：cognitive radio;realistic environment;M/G/1;systemic cost;interrupted times2|3|0更新时间：2025-07-16
- 摘要：This report introduces the technique of phaco-emulsification probe real-time tracking for cataract fragments which can eventually realize the using of intelligent control throughout the procedure of cataract operation.The key factors of smart phaco-emulsification techniques are:recognition of cataract and normal tissue;recognition of the color and hardness of cataract;real-time tracking of cataract fragments in the area near emulsifying probe;automatic control of the emulsion probe which could accord to the real-time results to release energy and avoid eye injury caused by over-released energy.The basic to this new method of phaco-emulsification probe real-time tracking for cataract fragments are Hough transform,k-nearest neighbor classifier and intelligent control technology.By analyzing the experiment results,this new method realizes the intelligent control of phaco-emulsification operation and improves the operation's safety and efficiency considerably.关键词：cataract;real-time tracking;Hough transform;intelligent control2|2|0更新时间：2025-07-16
- 摘要：Perceptual hashing is a one-directional mapping from multimedia data sets to the abstract sets ,which provides a safe and reliable tool for identification,retrieval,and authentication of multimedia digital contents.This paper proposes a video perceptual hashing algorithm fuseing visual perception and spatiotemporal features.The algorithm first randomly divides each video frame into a number of overlapping blocks,and then calculates the average brightness (AB) of each block.While spatial features are described by differences of the AB among blocks in the same frame,the features in time domain is represented by the differences of the same bock across time.Finally,the two features are quantized and fused to generate the unique id,i.e.abstract hashing for each video.The experimental results show that the features are robust,discriminative,and can effectively detect and accurately locate video tampering using correlation analysis.关键词：visual perception;time airspace;perceptual hash;copyright protection2|2|1更新时间：2025-07-16
- 摘要：Generalized least significant bit matching (G-LSB-M) steganography scheme is a ±1 embedding method which minimizes the number of modifications per pixel to improve the embedding efficiency.The sum and difference covering set (SDCS) used for embedding can only be obtained through exhaustive search,which is hard to implement when the number of message bits increases.To solve this problem,we provide a novel steganography method based on the extended SDCS (ESDCS).The ESDCS is constructed by removing redundant elements from the so-called basic SDCS without exhaustive search,which implies that longer message segments could be used in the embedding process.The proposed method reduces the expect number of modifications and thus improves the embedding efficiency as well as the security of steganography.关键词：extended sum and difference covering set;LSB matching;steganography;embedding efficiency2|2|0更新时间：2025-07-16
- 摘要：In this paper,we present an algorithm for locating errors in combinatorial testing,based on the set of possible faulty interactions (SPFI) constructed according to the result of combinatorial testing.By introducing the error density of each test case or interaction,we can analyze every test case which caused faults of the software under test,and then the additional test cases are generated to locate the faulty interaction.By constructing the set of possible faulty interactions,the same faulty interactions covered by different test case is avoid to be located repeatedly.And all of the faulty interactions can be located exactly when SPFI is empty.The final empirical results show that the number of test cases needed to locate all faulty interactions can be effectively reduced.关键词：combinatorial testing;locating errors;set of possible faulty interactions;error density4|2|6更新时间：2025-07-16
- 摘要：This paper proposes a logic for verifying security protocols in the computational model,which can describe the computation and communication actions precisely.We present a cryptographically sound proof system on the logic and can formalize the various security properties for encryption algorithms directly.During the research,several unsoundness of the formalization with the computational protocol compositional logic in prior work is discovered,and corresponding solutions are proposed.By proving the security properties for the Needham-Schroeder-Lowe protocol,the power of the logic is demonstrated.Being different from most of the current verification approaches,this logic reasons about the security of protocols from the security of cryptographic algorithms forwardly,and is both easy to use and cryptographically sound.关键词：encryption algorithms;security properties;formal logics;computational semantics4|2|3更新时间：2025-07-16
- 摘要：A new mode named azimuth-slow time waveform coding based on Alamouti space-time coding is presented.In azimuth,the total antenna array is divided into two sub-apertures for transmitting orthogonal waveforms that encoded by Alamouti coding matrix.In receiver,the total antenna array is divided into multiple sub-apertures forming multiple receive phase centers,which can be used for azimuth doppler ambiguity deduction,then the decoding of neighbor pulses can separate the orthogonal sub-waveforms thoroughly.This new method can enhance the echoes' SNR obviously and also realize high resolution wide swath imaging.The proposed system is of terseness,the aperture is fully explored,the SNR of echoes is improved,and the potential of multiple working modes simultaneously,etc.The simulation Results verify the system signal processing method.关键词：Alamouti space-time coding;MIMO-SAR;signal to noise ratio;high resolution wide swath imaging2|2|1更新时间：2025-07-16
- 摘要：With the development of compressive sensing theory,the space-time adaptive processing (STAP) technology based on sparsity of space-time power spectrum (STPS) receives a growing interest.This paper firstly reviews the traditional STAP algorithms and shows analysis of sparsity of STPS from three different points of view and potential advantages of STAP technology based on sparsity of STPS.Then,the current developed STAP algorithms based on sparsity of STPS are categorized into three classes,such as STAP based on prior knowledge of array manifold,STAP based on sparse recovery of STPS and STAP based on both prior knowledge of array manifold and sparse recovery of STPS.It also performs an overview of those algorithms.Finally,based on the progress of the existing research,some key issues to enhance the performance of clutter suppression and moving target detection are introduced,which include intrinsic mechanism analysis of sparsity,space-time steering dictionary design,easy parameters setting,fast and low complexity algorithms design,robust algorithm design,STAP algorithms based on sparse recovery of STPS design by exploiting different types of prior knowledge,and constant false alarm rate detector design of STAP based on sparsity of STPS and validation using measurement data.关键词：space-time adaptive processing;sparsity of space-time power spectrum;array manifold knowledge;clutter suppression;moving target detection;sparse recovery2|2|26更新时间：2025-07-16
- 摘要：How to effectively suppress transmissions of WSN(Wiretess Sensor Net work)and prolong its lifetime has become a hot area of research for WSN.In cluster-based WSNs,a precision configurable data aggregation algorithm(PCDA)is proposed.Through PCDA,every node adapts its threshold based on recent historical data so that nodes can suppress transmissions fairly;the adaptive threshold can control the error of aggregations in real-time.Theoretical analysis and experiment results show that nodes can save energy effectively through PCDA.Compared with Bernoulli sampling based aggregation,MAEs(Mean Absolute Errors)of continuous queries of sum aggregation and average aggregation is much smaller through PCDA.Furthermore,PCDA needs no future knowledge,making it usable and adaptive in many WSN applications.关键词：Wireless sensor networks;transmission suppression;data aggregation;error control2|2|21更新时间：2025-07-16
- 摘要：Although RFID(Radio Frequency Identification,RFID) is capable of identifying multiple tags synchronously,the tag collision occurs inevitably when a large number of tags respond in the induction area of reader simultaneously,which seriously influences the throughput of RFID system because signal aliasing arises from tags occupying the channel randomly.In order to further improve the throughput of RFID system,this paper proposes a new anti-collision algorithm with adjusting inventory cycle by the preset difference threshold,the slot checking forward,the slot predicting backward and the slot binary splitting,which are coordinately combined to deal with the response of the current slot and the next slot when algorithm complexity and hardware are not added in tags.In the algorithm,the preset difference threshold can prevent reader from floating point computation.Meanwhile,the methods of slot checking forward and predicting backward are joined together to judge the response of the current slot and the next slot in advance,which can skip the current idle slot and the next idle slot,and split the tags responding in the current collision slot and the next collision slot in real time.In the following three simulation experiments,ways of inventory cycle adjustment,methods of slot splitting,the identification delay and throughput are compared respectively.The results indicate that the improved anti-collision algorithm can raise the computation efficiency of reader,effectively reduce the time of channel occupied by invalid slots,and as a result,the throughput of RFID system can reach more than 52%.关键词：RFID;anti-collision algorithm;difference threshold;slot checking forward;slot predicting backward2|2|4更新时间：2025-07-16
- 摘要：A method is presented to design constant modulus waveforms with low magnitude of power spectral density and autocorrelation in desired intervals.The waveform design problem is transformed into a phase retrieval one,and three sets corresponding to different design objects and constraints are defined.The waveform optimization problem is solved via alternating projection.According to the relationship between the covariance matrix and the power spectral density of the colored noise,the projector used in the algorithm is implemented efficiently based on fast Fourier transformation.Thus the computational efficiency is improved.Finally,the numerical simulations demonstrate the effectiveness of this algorithm.The waveforms designed by this algorithm can be used in radar,sonar,and wireless communication systems to suppress colored noise,active interference and range sidelobes.关键词：waveform design;phase code;colored noise suppression;alternating projection;rank deficient Fourier transform3|2|5更新时间：2025-07-16
- 摘要：This paper presents a randomizing fingerprint-based Wu and Manber(WM) algorithm(RFP-WM),which can effectively reduce false positives rate by calculating a unique fingerprint for each pattern.Compared with WM algorithm,RFP-WM algorithm greatly reduces the hash collision rate and increases the hit rate,especially in the massive patterns set.Experiment results show that the performance of the RFP-WM algorithm is more superior than traditional Wu and Manber(WM) algorithm on the larger pattern set.关键词：fingerprint model;pattern matching;fingerprint-based Wu and Manber(WM) algorithm2|3|3更新时间：2025-07-16
- 摘要：According to the history of command sequence in Unix system,an approach to masquerader detection based on the closeness model of command was proposed.The behavior patterns of user were extracted from the view of command combinations.Those commands combined frequently by users showed close relationship,and other commands exhibited loose relationship.Command closeness matrix was generated by the sliding window from the sequence of commands.If the command block to be detected exhibited a low closeness for the user,it was judged as abnormal.Experimental results show that a simple calculation,an accurate detection,and a high level of real-time can be achieved by using the proposed approach.关键词：anomaly detection;masquerader detection;command closeness;shell;host3|2|4更新时间：2025-07-16
- 摘要：In the orthogonal frequency division multiple access(OFDMA)wireless broadband networks,the efficiency of random access can be improved by distributing contention onto multiple channels.However,due to the multichannel property,the traditional systems based on request-to-send(RTS)control frame have to encounter the idleness of subchannel,the extension of RTS transmission time and the complex synchronization of uplink communication.To solve these problems,in our scheme,the users send signals on random subcarrier to request transmission opportunity.The access point senses these request signals,and determines which user is permitted to access channel according to the busy state of the subcarriers.The theoretical analysis and simulation results both show that our scheme outperforms the traditional RTS-based schemes in term of the throughput.关键词：random access;multi-channel;subcarrier sensing;orthogonal frequency division multiple access(OFDMA)2|2|0更新时间：2025-07-16
- 摘要：The evaluation results of the Chen-Mobius transforms of some often-used waveforms are applied in the multi-carrier analog communication systems.In addition to traditional analog communication system,the new coherent modulation-demodulations systems by two classes of the oblique-orthogonal function set as the modulation and demodulation set are applied to multi-carrier analog communication systems.Then the new multi-carrier analog communication systems' performances are simulated by the MATLAB software on the computer and compared with the traditional system.The results are discussed.关键词：Chen-Mobius transformation;Chen-Mobius coherent modulation-demodulation system;Chen-Mobius multi-carrier analog communication system;MATLAB simulation2|2|0更新时间：2025-07-16
- 摘要：Aiming at the optimization of advanced encryption standard (AES) S-box,a novel multiple-term common subexpression elimination (CSE) algorithm was proposed.In order to simplify the combinational logic expressions,the common subexpressions containing the most factors took priority to be eliminated in the proposed approach,thus effectively reduced the area and latency of the GF(2^4) multiplicative inverse circuit and the isomorphic mapping circuit in S-box.The results show that the multiple-term CSE algorithm achieves high computation and optimization efficiency.The optimized S-box is implemented in 0.18μm CMOS technology.Compared with the smallest S-box and the shortest delay S-box in the existing work,the optimized S-box saves about 10.32% and 19.64% of the area-delay product separately.关键词：advanced encryption standard (AES);S-box;multiple-term common subexpression elimination (CSE) algorithm2|2|2更新时间：2025-07-16
- 摘要：This article researches the radio interference (RI) from the tower scattering of high-voltage power transmission line (HVPTL) to radio direction finding (DF) system.The theoretical simulation is verified by numerical analysis on the measured data.Two HVPTLs nearby a DF station were constructed.From the very beginning we started series tests based on the selected sites around the station.The analyzing and comparison of the test data shows that there is impact of the HVPTL to radio DF,the accuracy of the DF with spatial spectrum estimation is better than the one with correlative interferometer,which improved 1° and 0.5° in corresponding frequency band.关键词：direction finding;electromagnetic compatibility;radio interference;high-voltage power transmission line;numerical analysis4|2|1更新时间：2025-07-16
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