Table of Content

20 August 2014 Volume 41 Issue 4

  

Original Articles

Research on interferometric imaging for rotor synthetic aperture radar

YANG Ke;LIAO Guisheng;XU Qing

J4. 2014, 41(4):  1-5+30.  doi:10.3969/j.issn.1001-2400.2014.04.001

Abstract ( 736 )   PDF (2600KB) ( 739 )   Save

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To achieve the perception of 3D imaging in the complex environment in low-altitude space, an interferometric imaging model of rotor synthetic aperture radar (ROSAR) is established. The rotary axes of the platforms in different altitudes are shifted. By moving the rotary shaft and the observed scene holistically, the effects of the rotary shaft offset are equivalent to the changes of the scene position. Meanwhile, by analyzing the effects of the scene movement on the azimuth bandwidth and interferometric phase, we obtain the relation between slant range difference and offset amount. And then construct a compensation function to correct the additional phase. Simulation results demonstrate that this method can not only remove the effects of rotary shift offset effectively but also measure the height of the scene accurately.

High signal-noise-ratio high-resolution wide-swath imaging using two-dimensional intrapulse beam steering

ZHANG Jiajia;ZHOU Fang;SUN Guangcai;XING Mengdao;BAO Zheng

J4. 2014, 41(4):  6-12+150.  doi:10.3969/j.issn.1001-2400.2014.04.002

Abstract ( 668 )   PDF (1254KB) ( 734 )   Save

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The signal-noise-ratio (SNR) of synthesis aperture radar (SAR) will decrease as the swath becomes wider. To deal with this problem, a new practical SAR model based on the two-dimensional (2-D) intrapulse beam steering technique are presented to achieve high SNR and high-resolution wide-swath (HRWS) SAR imaging. The 2-D compact beam is formed by the whole plane-array antenna in the transmitter for the 2-D intrapulse beam steering. The range ambiguities in spatiality and the azimuth Doppler ambiguities caused by low pulse repetition frequency (PRF) sampling are solved by the 2-D digital beam forming (DBF) in the receiver, and then the high SNR HRWS SAR imaging can be obtained successfully. Simulation demonstrates that this SAR model improves the SNR of the HRWS system.

Novel feature extraction method for synthetic aperture radar targets

DUAN Jia;ZHANG Lei;XING Mengdao;LIANG Yi

J4. 2014, 41(4):  13-19.  doi:10.3969/j.issn.1001-2400.2014.04.003

Abstract ( 790 )   PDF (2182KB) ( 632 )   Save

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In order to extract geometric and electromagnetic features of targets from the radar echo, a novel parameter estimation algorithm for attributed scattering center decomposition and extraction is presented, which is steady and fast. By simplifying the model with consideration of real synthetic aperture radar working conditions, a simplified model is deduced. It is used to construct the base to represent the radar echo. The RELAX algorithm is utilized to determine the model parameter in an iterative way, with fast Fourier transform used for acceleration. Moreover, the maximum searching intervals and ranges are deduced in literature. Both simulated data and real measured data illustrate that our method is not only precise but also robust. Moreover, through the comparison with traditional methods, the efficiency has been improved effectively.

Personal recognition with nose area biometrics

LI Yunfei;LU Zhaoyang;LI Jing;YAO Chao

J4. 2014, 41(4):  20-25+165.  doi:10.3969/j.issn.1001-2400.2014.04.004

Abstract ( 710 )   PDF (3520KB) ( 622 )   Save

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The nose area of a face can provide some stable individual characteristic information for personal recognition because of its tiny changes affected by expression, weight and hairstyle. The paper first dissects the physiological structure of the nose and discusses the feasibility and characteristics of nose recognition. Furthermore, authors simplify Gabor's parameters in extracting nose features, and compare the recognition effect by experiment with the Gabor Kernel Fisher Discriminant Analysis in different databases. Experiment shows that the nose area has a better recognition result than the face when the face image has a rich expression or wide range poses.

Influence of drain contact to gate space on the characteristic of the GGNMOS protection device

WU Xiaopeng;YANG Yintang;DONG Gang;GAO Haixia

J4. 2014, 41(4):  26-30.  doi:10.3969/j.issn.1001-2400.2014.04.005

Abstract ( 734 )   PDF (697KB) ( 860 )   Save

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Based on the test data, the influence of DCGS on the single finger GGNMOS ESD protection device is investigated. The changing tendency of the failure current level is given by the TLP test under various layout parameter conditions realized in the SMIC 018μm CMOS process. Electrical and thermal distribution is detailed based on the device simulation. The results show that the peak value of the current density is moved in the opposite direction to the channel, which lowers the risk of LDD discharge. Meanwhile, the failure current level shows the saturation tendency because of the heat balance of the drain and substrate region which appears when the DCGS is raised to the threshold value.

TDOA location algorithm based on multi-reference receivers

ZHU Guohui;FENG Dazheng;ZHOU Yan

J4. 2014, 41(4):  31-35+57.  doi:10.3969/j.issn.1001-2400.2014.04.006

Abstract ( 723 )   PDF (533KB) ( 785 )   Save

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A new algorithm based on multi-reference receivers for the passive location from time difference of arrival (TDOA) is proposed. The proposed algorithm first transforms the nonlinear TDOA equations into a set of pseudo-linear equations of the emitter position, and then the weighted least squares algorithm is applied to obtain the initial solution. By taking the relationship among the entries of the initial solution into account, we get a set of more accurate emitter position estimates via the weighted least squares algorithm with the obtained initial solution, the average of these estimates is then taken as the final estimate of the emitter position. Simulation results show that the proposed algorithm achieves high positioning accuracy for both near and far field emitters.

Novel distributed optimal interconnection power model

ZHANG Yan;YANG Yintang

J4. 2014, 41(4):  36-40+192.  doi:10.3969/j.issn.1001-2400.2014.04.007

Abstract ( 661 )   PDF (517KB) ( 663 )   Save

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Based on the lumped interconnection power model, a distributed dynamic power model is presented first. Then by adopting a non-uniform interconnection structure, a novel optimal interconnection power model is proposed, which is constrained by delay, bandwidth, area, minimum interconnection width and minimum interconnection space. The validity of the proposed model is verified by 90nm and 65nm CMOS technology. The results indicate that the proposed model can reduce power consumption as high as 30％, with the delay, area, bandwidth not deteriorated. The proposed optimal model can be used for the interconnection optimal design in large scale integrated circuits.

Novel error estimation method for stepped frequency chirp SAR

WU Mingyu;YANG Taoli;WU Shunjun;LI Zhenfang

J4. 2014, 41(4):  41-46+70.  doi:10.3969/j.issn.1001-2400.2014.04.008

Abstract ( 740 )   PDF (4681KB) ( 481 )   Save

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To reconstruct the spectrum of a wide band signal by stepped-frequency chirp signals, the mismatch between sub-band signals should be compensated, a novel method is proposed in this paper to estimate the sub-band errors depending on the overlap spectra between sub-band signals, with the amplitude-phase error and the time delay error between sub-band signals estimated by fitting the interferometric phase of the overlap spectra components. Besides, the window for eliminating the ghost images caused by the overlap spectra is proposed. Finally, the computer simulation and the ground-based real data confirm the validity of the method.

Design of a novel broadband omnidirectional antenna

ZHANG Yunqi;WANG Liang;LI Xi;YANG Lin;GONG Shuxi

J4. 2014, 41(4):  47-50+107.  doi:10.3969/j.issn.1001-2400.2014.04.009

Abstract ( 786 )   PDF (1653KB) ( 1099 )   Save

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The omnidirectional antennas have been widely used in the next generation of wireless communication systems. A novel cross feed broadband omnidirectional antenna is presented in this paper. The wideband is realized by adding the bulun and wider dipole. Two elements are cross-fed by parallel broadside coupled lines to actualized impedance match. Theoretical analysis of dipole and simulation results with HFSS and measurements of the antenna show that the antenna fabricated on the substrate with thickness of 1.5mm and relative permittivity of 2.6 can achieve an impedance bandwidth of 44.7％ for VSWR<2. The far-field radiant characteristics are good. The out-of-roundness is less than 2.3dB and the gain is higher than 1.6dB. The antenna is simple in structure and easy to fabricate, and it has a wide application.

Shuffled frog leaping algorithm using dynamic searching strategy

JIANG Jianguo;ZHANG Liyuan;SU Qian;DENG Lingjuan;LIU Mengnan

J4. 2014, 41(4):  51-57.  doi:10.3969/j.issn.1001-2400.2014.04.010

Abstract ( 717 )   PDF (1498KB) ( 781 )   Save

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Based on the principle of the shuffled frog leaping algorithm (SFLA), the algorithm's optimization mechanism is studied. A novel shuffled frog leaping algorithm is proposed to solve the problems of the original SFLA, such as non-uniform initial population, slow convergence speed in later iterations, and being easy to fall into local optimum. The improved algorithm generates the initial population with the random uniform design method, changes the influence of the subgroup's current worst value on the subsgroup's evolution behavior dynamically by using the influence factor. Besides, the variance of the population's fitness is calculated to judge whether the population falls into local optimum, and then the improved algorithm makes the population jump out of local optimal state by the perturbation of the current global optimal value. Experimental results show that the improved algorithm can lead to a higher convergence accuracy and a better convergence result.

Small target detection utilizing the narrow wavebands

LIN Tao;HAN Pingli;LIU Fei

J4. 2014, 41(4):  58-63+157.  doi:10.3969/j.issn.1001-2400.2014.04.011

Abstract ( 734 )   PDF (3293KB) ( 569 )   Save

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The aim of this paper is to solve the target detection after the background suppression in infrared small target detection. A method based on the color ratio of different narrow wavebands is proposed to fuse the residual images. There are four main procedures in the whole detection: first, the background for residual images is suppressed; second, the fused residual images with improved SNR are obtained by color ratio calculation; third, the concentrated target energy in the images is obtained by employing the target volume detection method bringing a higher SNR of the image; finally, threshold segmentation would find the targets more precisely compared with traditional segmentation. The proposed method has advantages of being unacted on the clutter and reducing the false alarm rate.

Analysis of thermo-elastic coupling effects of the beam structure with interval parameters

YUN Yonghu;CHEN Jianjun;ZHAO Kuan;YAN Bin;CAO Hongjun

J4. 2014, 41(4):  64-70.  doi:10.3969/j.issn.1001-2400.2014.04.012

Abstract ( 711 )   PDF (592KB) ( 682 )   Save

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The dynamic response of thermo-elastic coupling of the beam structure with interval parameters is studied under both the thermal load and force load. The dynamic model of thermo-elastic coupling is set up using the finite element method. The coupled calculation method is proposed for solving the transient temperature field and dynamical response by iterative solution, in which the finite difference method is used for solving the transient temperature field, and time integration method is used for solving structural dynamic response. The equations for the model with interval parameters are solved by the improved Monte Carlo numerical simulation method assuming that each variable is uniformly distributed, and then the interval distribution range of the dynamic response is determined. Finally, the thermo-elastic coupling effect on the dynamic response of the cantilever beam is analyzed. Numerical examples show that the thermo-elastic coupling effect is mainly determined by the increased interval range of the elastic modulus and thermal expansion coefficient influence and the magnitude of deformation.

Adaptive synchronization for unknown complex dynamical networks with non-identical nodes

HAO Xiuqing;LI Junmin

J4. 2014, 41(4):  71-76.  doi:10.3969/j.issn.1001-2400.2014.04.013

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An adaptive synchronization approach for unknown complex dynamical networks with non-identical nodes and nonlinear coupling with time-varying delays is proposed via learning control. By using the signal replacement technique and reconstructing the system equation, all unknown time-varying terms are combined into a periodically time-varying vector which is estimated by a periodic adaptive learning mechanism. A sufficient condition for the synchronization and boundedness of all signals are given by constructing a composite energy function. Finally, a numerical example is given to show the effectiveness of the designed method.

Improved algorithm of self-calibration technology by the ground-based microwave radiometer

LI Jiangman;GUO Lixin;LIN Leke;ZHAO Zhenwei;SHU Tingting;CHEN Houcai

J4. 2014, 41(4):  77-81.  doi:10.3969/j.issn.1001-2400.2014.04.014

Abstract ( 780 )   PDF (504KB) ( 650 )   Save

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The calibration precision of the microwave radiometer affects the retrieval precision of atmosphere directly. Based on the self-calibration technology of the ground-based microwave radiometer in the American Atmospheric Radiation Measurement Program, this article deduces the general forms of self-calibration by the ground-based microwave radiometer. Due to the error of self-calibration during nonstratified atmosphere conditions, an improved method of self-calibration is proposed which searches for the best expiation error of different elevations after original self-calibration. The regression curve will approach the origin and the relative coefficient will approach 1. The measured brightness temperature of the dual-frequency microwave radiometer after self-calibration is compared with the brightness temperature simulated by the sounding data. The results show the validity of the improved self-calibration technology.

Low energy consumption NoC mapping algorithm based on the modified electromagnetism-like mechanism

ZANG Mingxiang;WANG Ting;ZHOU Wenhong

J4. 2014, 41(4):  82-86+93.  doi:10.3969/j.issn.1001-2400.2014.04.015

Abstract ( 622 )   PDF (563KB) ( 664 )   Save

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A low-energy mapping algorithm based on the modified electromagnetism-like mechanism is proposed. Real number coder is used to realize the transformation of electromagnetism-like algorithm from continuous to discrete space. To improve the initializing particle quality and the algorithm efficiency, roulette wheel selection is used for population initialization. Adjustment sequence is designed to improve the efficiency of searching local fine particles. The new charge formula is proposed to get the force, and some particles are filtered out to improve the efficiency. Experimental results shows that the proposed algorithm is more efficient in energy optimization. Compared with the existing genetic algorithm and ant colony algorithm, the electromagnetism-like mapping algorithm has a more evenly distributed energy consumption, and the algorithm can also save 20.35％ and 12.58％ energy on average.Thus the energy consumption of the NoC is effectively reduced.

Blind estimation algorithm of sampling frequency offset for the OFDM system over multipath channels

LI Bingbing;SUN Jun;LIU Mingqian

J4. 2014, 41(4):  87-93.  doi:10.3969/j.issn.1001-2400.2014.04.016

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In order to improve the performance of sampling frequency offset(SFO) estimation for the Orthogonal Frequency Division Multiplexing(OFDM) system in practical non-cooperation communications, this paper proposes a new sampling frequency offset estimation for the OFDM system estimation algorithm  in multipath fading channels and the non-cooperation communications system. The proposed algorithm first uses an improved cycle spectrum to make a coarse estimation of the relative point, and then estimates accurately the relative point through another improved cycle spectrum. Finally, the estimated values of sampling frequency offset are obtained by the rate of change of the phase of the cycle spectrum in the relative point after jumping phase change and least square fitting. Simulation results show that the proposed algorithm has not only higher estimation accuracy but also better performance over multipath channels.

Application of the hybrid invasive weed optimization algorithm to the shaped beam synthesis of array antennas

LIU Yan;JIAO Yongchang;ZHANG Yaming;WANG Xinkuan

J4. 2014, 41(4):  94-99.  doi:10.3969/j.issn.1001-2400.2014.04.017

Abstract ( 677 )   PDF (955KB) ( 685 )   Save

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For overcoming the problem of slow convergence speed and local optimum in handling the high-dimension complex problem by the Invasive Weed Optimization Algorithm(IWO), a hybrid Invasive Weed Optimization Algorithm(HIWO) is proposed by integrating the Simplified Quadratic Interpolation(SQI) method into the IWO. The SQI Method is integrated in the IWO as a local search operator to enhance the performance of the algorithm, improve the convergence speed and computation accuracy. Simulation results for different design requirements show that the proposed algorithm performs better than other existing algorithms in the problem of shaped beam synthesis of array antennas.

Image super-resolution using generalized nonlocal mean and self-similarity

WU Wei;ZHENG Chenglin;ZHANG Yingying;ZHOU Shouhuan

J4. 2014, 41(4):  100-107.  doi:10.3969/j.issn.1001-2400.2014.04.018

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A super-resolution method based on generalized nonlocal mean and self-similarity is proposed. The proposed method not only adopts the self-similarity of the image by taking the low-resolution image and its downsampled version as a training set but uses the nonlocal mean algorithm to improve the quality of the restored image. The proposed method first extracts the features of the low image by using the difference of Gaussians, and then a generalized nonlocal mean algorithm is adopted to estimate the high-frequency details of the low image. Experimental results show that the proposed algorithm has a good performance, and that the high-resolution image generated by the proposed method is of better subjective and objective quality compared with other methods.

Improved curvelet thresholding denoising method by the Chi-Squared cumulation distribution function and PDE

CUI Hua;YAN Gabeng

J4. 2014, 41(4):  108-110+172.  doi:10.3969/j.issn.1001-2400.2014.04.019

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To circumvent the visual distortion due to the discontinuity of the hard threshold function and the constant reconstruction deviation caused by the soft thresholding function, this paper presents a novel thresholding function based on the Chi-Square cumulative distribution function according to the distribution characteristics of curvelet coefficients of the noise and the ideal properties thehigh effective curvelet threshold functions should have. Further, in order to eliminate the surrounding effect inherent in curvelet threshold denoising methods and achieve a better balance between detail conservation and noise reduction, useful information involved in a denoised image produced by the partial differential equation denoising method is fused with that by the novel curvelet threshold function into the proposed denoising method. Theoretical analysis and simulation results show that the proposed denoiding method outper forms the soft and hard threshold denoising methods in terms of the denoising effect and visual quality.

Spectrum allocation algorithm based on parallel immune optimization

WU Huixin;WANG Bing;CHAI Zhengyi

J4. 2014, 41(4):  111-115+136.  doi:10.3969/j.issn.1001-2400.2014.04.020

Abstract ( 746 )   PDF (511KB) ( 647 )   Save

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The graph-theory based spectrum allocation in the cognitive wireless network is an NP-hard problem. Intelligent optimization is an effective method for solving this problem. Real-time is one of the notable features of the spectrum allocation problem in cognitive radio networks which differ from others. A spectrum allocation algorithm based on the master-slave parallel immune optimization model is proposed. The antibody affinity in the population is calculated in multiple computing nodes at the same time. The main idea of the algorithm, key technologies and implementation steps are given. Simulation results show that the algorithm can achieve higher network profits and can shorten the time of spectrum allocation. Compared with the traditional serial algorithm, the proposed algorithm can get ideal speedup and efficiency.

New space-time coded transmission scheme for the X channel

TIAN Xinji;LU Jing

J4. 2014, 41(4):  116-122.  doi:10.3969/j.issn.1001-2400.2014.04.021

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A new space-time coded transmission scheme is proposed for the X channel with four antennas at each user who employs the rate-2 space-time block code. Each codeword is pre-coded, and then the addition and subtraction combinations of each codeword after pre-coding are transmitted separately. The number of interferential coding matrices is reduced through addition and subtraction operations of the received signals, and then the multi-user interference is eliminated by proper pre-coding at the transmitters and linear processing at the receivers. Compared with the existing scheme, the proposed scheme not only greatly reduces the feedback amount, but also significantly improves the system reliability.

Unconstrained criterion for blind equalization using the property of the norm

WANG Dalei;YANG Bin;WU Ying;WANG Xiuxiu

J4. 2014, 41(4):  123-129+143.  doi:10.3969/j.issn.1001-2400.2014.04.022

Abstract ( 728 )   PDF (659KB) ( 691 )   Save

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A novel unconstrained criterion for blind equalization is proposed. The algorithm is based on minimization of the difference between two norms, and does not need to impose any constraint on the equalizer coefficients, which can be realized by the batch processing method and online adaptive approach. Based on the convergence proof under the noiseless condition, we show that a perfect equalization solution is achieved at every local optimum of the function, and that the amplitude of the input signal can be recovered. The validity and good performance in terms of convergence and the steady-state error of the proposed algorithm are verified through computer simulations.

Real-time 3D bare-hand gesture recognition using binocular vision videos

GONG Yanchao;WAN Shuai;YANG Kaifang;CHEN Hao;LI Bo

J4. 2014, 41(4):  130-136.  doi:10.3969/j.issn.1001-2400.2014.04.023

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Current bare-hand based gesture recognition algorithms generally have the problems of low recognition accuracy and being prone to be affected by skin-like objects. In this paper, a 3D bare-hand gesture recognition algorithm is proposed using binocular vision videos. Firstly, a relationship between the depth and area of the gesture is achieved according to the principle of binocular vision, on the basis of which fast 3D gesture recognition is realized. To further speed up the method, a fast stereo matching algorithm is proposed following the epipolar line constraint rule, which regards the gesture's centroid as the matching point. Experimental results have demonstrated that compared with existing algorithms the proposed algorithm significantly improves the performance in processing speed, recognition accuracy, and robustness. It should be noted that the proposed algorithm is open, where more 3D gestures can be easily added upon requirement.

Static multi-service deployment algorithm on the overlay network

TUO Liheng;NI Hong;LI Mantian;LIU Xue

J4. 2014, 41(4):  137-143.  doi:10.3969/j.issn.1001-2400.2014.04.024

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The Static Multi-Service deployment Model SMSPM for short, is proposed to deal with the problem of overlay network multi-service deployment on the Internet. The SMSPM minimizes the scale of service deployment as a target and guarantees the average request forwarding delay to satisfy the quality of service. Based on single service deployment, the SMSPM allocates multiple services to different service nodes We introduce the concurrent upper limit on the number of concurrents in a single node to use reasonably server resources of service nodes. We prove that the SMSPM problem is NP-Complete. We propose two greedy heuristic algorithms, NBND and BND. NBND and BND can solve the problem in the polynomial time. Experimental results show that NBND and BND. SMSPM and two greedy heuristic algorithms can greatly lower the scale of multi-service deployment. BND and NBND can reduce the scale of multi-service deployment to 41％ and 47.8％ of the original scale of multi-service deployment.

Dendritic cell algorithm for time series oriented anomaly detection

TIAN Yuling

J4. 2014, 41(4):  144-150.  doi:10.3969/j.issn.1001-2400.2014.04.025

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Aiming at the fact that the high randomness existing in definitions of signals and the antigen results in the lower detection rate used by the Dendritic Cell Algorithm, the Dendritic Cell Algorithm for anomaly detection based on time series is proposed. The underlying methodology is to perform antigen detection via the change point detection and multiple data streams correlation analysis, and the change point data reflecting the mutation status as the candidate solution of the abnormal is selected. Features are extracted based on the subspace tracker algorithm and various input signal subspaces are obtained and classified precisely. A dynamic migration threshold is incorporated into the context evaluation of the algorithm. The accumulation of the antigen assessment in a certain window time decreases the false positive rate effectively. Simulation demonstrates that the algorithm shows a better performance on the detection rate, accuracy rate and stability with less memory space and computing resource.

Design of a segmented and blocked compressive sampling model

FANG Biao;HUANG Gaoming;GAO Jun;ZUO Wei

J4. 2014, 41(4):  151-157.  doi:10.3969/j.issn.1001-2400.2014.04.026

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Based on the analysis of the existing analog-to-information converter (AIC) under the framework of CS, a novel model called the segmented and blocked AIC (SB-AIC) based on block diagonalization is proposed. In this model, the measurement matrix is transformed into a structured block diagonal matrix and the block storage can be reused depending on the relative independence. Besides, the integral time of each branch can be reduced, which can be applied to mass compressive sampling per unit time. Experimental results show the effectiveness of this method, with complexity lower and practicality higher compared with the parallel AIC state of art.

Novel high gain and low RCS microstrip antenna

GAO Jun;YUAN Zidong;CAO Xiangyu;YANG Jiming;LIU Tao;YANG Huanhuan

J4. 2014, 41(4):  158-165.  doi:10.3969/j.issn.1001-2400.2014.04.027

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A double screen frequency selective surface(FSS) is designed and applied as the radome of the microstrip antenna. By analyzing the transmission line model and simulating the electric field distribution and current distribution on the double screen frequency selective surface at the resonance frequency, its physical mechanism of wave-transparent is theoretically investigated. The new antenna high-gain and in-band radar cross section(RCS) reduction mechanism is analyzed by the ray theory and phase cancellation principle. Simulation and measurement results demonstrate that: the application of the double screen FSS has hardly influence the bandwidth of the antenna, while the gain of antenna is enhanced by 5.49dB, the half-power beam width of the E-plane and H-plane is reduced 63° and 52°, respectively. The RCS of the antenna is reduced by 5dB or more in an operation band from 2～18GHz, and the in-band RCS reduction of the antenna is above 5dB from -23°～23° and the maximum reduction value exceeds 20.94dB in the boresight direction.

MM-LS time registration algorithm in middle guidance using multi-sensor information

YONG Xiaoju;FANG Yangwang;GAO Xiang;ZHANG Lei;FENG Puwen

J4. 2014, 41(4):  166-172.  doi:10.3969/j.issn.1001-2400.2014.04.028

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The application of LS time registration has been restricted by both the assumption of the uniform motion of the target and the assumption that the ratio of the registration period to the sensor sampling period is an integer. The MM-LS time registration algorithm under no restriction has been studied in this paper. Based on the model of the uniform accelerated motion and accelerated linear motion, the MM-LS time registration algorithm has been obtained with the rule of MMSE. With the first order, second order, and third order derivative achieved through each model, the problem of non-integer ratio is solved by the extrapolating algorithm. Simulations indicate that the performance of MM-LS is always reliable when the maneuver overload of the target changes from 1g to 9g, and that the precision of radar changes from 10m to 100m.

Distributed storage algorithm with high performance for the UWSN

XIAO Yilong;JIANG Haibo

J4. 2014, 41(4):  173-178+185.  doi:10.3969/j.issn.1001-2400.2014.04.029

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To solve the data storage reliability problem of the unattended wireless sensor network consisting of n sensor nodes, this paper proposes a new distributed storage algorithm based on parallel directional random walk with length cn.  The proposed algorithm disseminates each of k source data packets in the network according to a given probability and formes a stored data packet in every node. Simulation results show that, after the storage process based on the proposed algorithm is completed, even if some stored data packets are missing, the data collector node can successfully recover the k source data packets from any survival k+ε, ε≥11 stored data packets. Compared with the LT codes based algorithm, the proposed algorithm reduces Sink node's query cost from k+100 to k+11 and reduces the network's communication cost from 3nlnn to 3n.

New vector control of the permanent magnet synchronous motor

CHEN Junshuo;LIU Jinglin;ZHANG Ying

J4. 2014, 41(4):  179-185.  doi:10.3969/j.issn.1001-2400.2014.04.030

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This paper presents a new vector control, which overcomes drawbacks of the conventional AC servo system. The novel concept is based on predictive control and introduces the automatic differentiation method to make the calculation of the Taylor coefficients into a simple numerical calculation. The permanent magnet synchronous motor(PMSM) model and a quadratic performance index of the system error are expressed by the Taylor expansions. Then solving the Jacobian matrix is transformed into solving the sensitivity of the Taylor coefficients. Combined with the Levenberg-Marquardt algorithm, the concept has been developed by a new speed controller of PMSM. Results of dSPACE real-time simulation show that the designed controller improves the system robustness, and has good dynamic and static characteristics.

Calculation methods for nodal multilink weight in the directed manufacturing grid

ZHANG Lu;CAI Wandong;PENG Dong

J4. 2014, 41(4):  186-192.  doi:10.3969/j.issn.1001-2400.2014.04.031

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A novel control model of the manufacturing grid based on Web technology is established. It describes the directed control process of the manufacturing grid and has the features of manageability and controllability. A notion of status collection agent is proposed in the process of model establishment. And the mechanism in which status collection agents improve the management efficiency and controllability in manufacturing grid cooperative control of the management process is introduced. According to the characteristics of the directed manufacturing grid control model, a method for computing the weight of the directed manufacturing grid node based on the multilink is proposed. Status collection agents are identified in the light of former sort results. Contrastive experiments on different recognized algorithms of status collection agents are conducted by adopting T-Test, Kendall-tau and Spareman Rank statistic tests, and in the meantime, experiments have been performed on the accurate rate and recall rate of the algorithm and calculating time. The results show that this method is better from comprehensive specifications of recognition capability on status collection agents, accurate rate, recall rate and computing time.

Method to compute the strict minimal siphon for S³PR

YOU Dan;LIU Miao;WU Wenhui;WANG Shouguang

J4. 2014, 41(4):  193-197+204.  doi:10.3969/j.issn.1001-2400.2014.04.032

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Petri nets are used to model the concurrent execution and the deadlock problem in a flexible manufacturing system (FMS). Strict minimal siphons (SMS) play an important role in the development of deadlock control policies for FMS. In this paper, for a class of Petri nets called Systems of Simple Sequential Processes with Resources (S³PR), we propose a more effective method to compute SMS by analyzing a special class of places in S³PR. First, the concept of special places is proposed. Next, by analyzing the relationship between the special places and the loop resource subsets, some conditions for loop resource subsets to generate SMS are established. Based on those conditions, we can compute SMS effectively. Experimental results show that the proposed method is an effective one when the special places exist in S³PR.

Trust and behavioral modeling based two layer service selection

MENG Xianjia;MA Jianfeng;LU Di;WANG Yichuan

J4. 2014, 41(4):  198-204.  doi:10.3969/j.issn.1001-2400.2014.04.033

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In the Service-Oriented Architecture(SOA), the consumer has many experiences in service,and then based on the experiences he builds trust and reputation. But lack of experiences or a malicious adviser will lead to unfair selection. In this paper,we propose a two-layer selecting algorithm to meet the demand of the consumer. In the first layer the consumer uses social records update his own to get more accurate experience. Afterwards, in the second layer, the consumer selects the most suitable. The result shows that our approach will filter the malicious participants,and then chose the services which fit consumer's preference.