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Technique of Doppler compensation for phase-coded signal pulse compression

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Technique of Doppler compensation for phase-coded signal pul...

2006 CIE International Conference on radar

作者： Zhang Yanyan Jiang Lifeng Song Wanjie Wu Shunjun national lab of radar {3. processing xidian Univ. xi’an china 710071

Codes used in phase-coded pulse compression waveforms suffer from Doppler *** on an analysis of the effects of Doppler mismatch on quariphasecoded waveforms and the performance results,a new technique of Doppler compensation is *** technique solves the problem of the sensitivity of phase-coded signal to *** is proved that pulse compression performance is quite well by using this technique,and it meets the project’s requirement very well.

关键词： Phase-coded signal pulse compression Doppler compensation Taylor quadriphase code

radar Automatic Target Recognition Based on Complex High-Resolution Range Profiles

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Radar Automatic Target Recognition Based on Complex High-Res...

2006 CIE International Conference on radar

作者： Lan Du Hongwei Liu Zheng Bao national lab.of radar {3. processing xidian University xi’an china

radar high-resolution range profile （HRRP） has received intensive attention from the radar automatic target recognition （RATR） ***,complex HRRPs are not fully used for RATR but only their amplitude vectors,while the phase information of them is discarded due to the fact that the initial phase of a complex HRRP is strongly sensitive to target position ***,the phase information of complex HRRPs may also contain valuable target discriminant information,which may further improve the recognition *** paper concerns RATR using complex *** deal with the initial phase sensitivity of complex HRRPs,we extract the complex HRRPs’ feature subspace within each target-aspect sector of each target via principal component analysis （PCA） as the corresponding template during the training phase,while in the test phase,project the test sample onto each feature subspace and search the optimal approximation of the test sample with the minimum reconstruction error to decide which target the test sample belongs *** is shown that the whole process is independent of the initial phases of complex ***,to make the proposed recognition method more practical,a fast time-shift compensation algorithm is *** the recognition experiments based on measured data,the proposed recognition method using complex HRRPs achieves better recognition results than that using only the amplitude vectors of the complex HRRPs.

关键词： radar automatic target recognition (RATR) complex high-resolution range profile (complex HRRP) initial phase sensitivity time-shift sensitivity principal component analysis (PCA) minimum reconstruction error approximation

An approach to sample broadband radar signal with low-rate ADC using adaptive beamforming technique

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An approach to sample broadband radar signal with low-rate A...

2006 CIE International Conference on radar

作者： Ma Lun Li Zhenfang and Liao Guisheng national lab.of radar {3. processing xidian University xi’an china

To directly sample broadband radar signal with high-rate Analog-to-Digital Converter（ADC） suffers from high cost and low sampling *** this paper a novel method is presented to sample a wide-band signal with multiple low-rate ADC channels by using adaptive beamforming *** method has the advantages of low cost,low sampling rate,high precision,easy implementation,and it is robust to channel *** effectiveness of the proposed approach is verified by simulated data.

关键词： Analog-to-Digital Converter(ADC) Adaptive beamforming Multi-channel sampling

Multiuser detection and independent component analysis——Progress and perspective

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Progress in Natural Science:Materials International 2002年第7期 15-22页

作者： JIAO Licheng , MA Haibo and LIU Fang( State Key laboratory for radar signal {3., xidian University, xi’an 710071, china) State Key laboratory for radar signal {3. Xidian University Xi'an 710071 China

The latest progress in the multiuser detection and independent component analysis (ICA) is reviewed systematically. Then two novel classes of multiuser detection methods based on ICA algorithms and feedforward neural networks are proposed. Theoretical analysis and computer simulation show that ICA algorithms are effective to detect multiuser signals in code-division multiple-access (CDMA) system. The performances of these methods are not identical entirely in various channels, but all of them are robust, efficient, fast and suitable for real-time implementations.

关键词： code division multiple access (CDMA) multiuser detection independent component analysis (ICA).

Automatic Target Recognition based on SAR images and Two-Stage 2DPCA features

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Automatic Target Recognition based on SAR images and Two-Sta...

2007 Asian and Pacific Conference on Synthetic Aperture radar(APSAR 2007)

作者： Liping Hu Jin Liu Hongwei Liu Bo Chen Shunjun Wu national lab. of radar {3. processing xidian University xi’an china 710071

2-dimensional Principal Component Analysis （2DPCA） has received more and more attentions in recent years,since it can evaluate the covariance matrix more accurate than PCA in extracting features from 2-dimensional images. However,a drawback of 2DPCA is that it needs more features than PCA because 2DPCA only eliminates the correlations between rows. In this paper,two-stage 2DPCA is proposed to extract features from synthetic aperture radar （SAR） images to further compress the dimension of features and decrease the recognition computation. Experimental results based on MSTAR data indicate that two-stage 2DPCA can decrease feature dimensions significantly,and the target recognition performance can be improved at the same time.

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Optimizing and Implementing the Fast Algorithm for Real Time SAR Imaging

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Optimizing and Implementing the Fast Algorithm for Real Time...

2006 CIE International Conference on radar

作者： Tao Su 1 Xuehui He 1 Shunjun Wu 1 1 national Key lab.for radar {3. processing xidian University xi’an 710071 china

A fast correlation algorithm in SAR imaging is presented to lower down the computation burden of range compression and azimuth focusing *** is based on the decomposition method of *** order to minimize the computation amount,the relationship of number of padding zeroes and the decomposition scheme to computation complexity is investigated,which is dependent on the number of correlation filter coefficient *** for different numbers of correlation filter coefficient taps,the number of padding zeroes and decomposition scheme are *** algorithm is superior in computational efficiency compared with other *** is applied to real time SAR imaging and proved to be effective in computation.

关键词： decomposition optimizing

Multistage decomposition algorithm for blind source separation

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Progress in Natural Science:Materials International 2002年第5期 60-64页

作者： FENG Dazheng, BAO Zheng and ZHANG xianda(Key laboratory for radar signal {3., xidian University, xi’an 710071, china) Key laboratory for radar signal {3. Xidian University Xi'an 710071 China

A new algorithm for blind source separation is proposed, which only extracts the single independent component at each stage. The single independent component is acquired by an iterative algorithm for searching for the optimal solution of the defined cost function. Moreover, all the independent components are obtained by systematic multistage decomposition and multistage reconstruction. When there is spatially colored noise, the performance of this algorithm is advantageous over jointly approximated diagonalization of eigen-matrices (JADE) . Simulated results show that if the number of source signals is more than 25, its computational complexity is lower than that of JADE.

关键词： blind source separation multistage decomposition multistage reconstruction criterion iteration algorithm.

A theoretical model for impact protection of flexible polymer material

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 217-226页

作者： Huifeng xi Hui Pan Song Chen Heng xiao MOE Key lab of Disaster Forecast and Control in Engineering School of Machanics and Construction EngineeringJinan UniversityGuangzhou 510632China Doctor Workstation of Xuwen County Guangdong Hydropower Energy Co. Ltd.Xuwen 524100China

The relationship between the protective performance of flexible polymer material and material parameters(elasticmodulus,viscosity coefficient)is explored,an impact collision motion equation between two bodies is establishedfrom the viscoelastic material constitutive,and the relationship between the kinematic response and the materialparameters is *** on the Kelvin constitutive model,a theoretical model for impact between the pro-tective body and the protected body is established,then the dynamic response is *** feasibility of themodel was verified by drop hammer experiment,and the material parameters(elastic modulus,viscosity coeffi-cient)were obtained by *** model is discretized and the relationship between local impact response andmaterial parameters is *** discussion results on the relationship between the impact response and theprotective material performance indicate that adjusting the elastic modulus,viscosity coefficient,and thicknessof the protective material can effectively improve protective effect.

关键词： Flexible polymer material Viscoelastic material Kelvin modelDynamic response Elastic modulus and viscosity coefficient

维普期刊数据库

A Novel Blind Space-Time Multiuser Detector

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A Novel Blind Space-Time Multiuser Detector

2002年第6届信号处理国际会议

作者： Ling Wang Licheng Jiao Senior Member IEEE and Fang LiuKey lab for radar signal {3. xidian University xi’an china 710071

＜正＞ Multiple access interference（MAI） is a key problem in DS-CDMA systems. Both multiuser detector and array antenna have been introduced to reduce the effect of MAI respectively. Many existing multiuser detectors require so many system parameters and their adaptive versions require training sequence. These parameters are difficult to obtain in multipath fading *** this paper, a novel blind space-time multiuser detector based on Kalman filter is *** numerical simulations and performance analysis, it is shown that the detector precedes other existing detectors in eliminating MAI and near-far resistance. Furthermore, it can converge rapidly.

关键词： DS-CDMA Blind multiuser detection Space-time processing Multiple access interference