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Table of Content

    28 October 2014, Volume 48 Issue 10 Previous Issue    Next Issue
    Radiao Electronics, Telecommunication Technology
    Analysis of Photo-Electronic Signal Characteristics and Optical Optimization for Detection of Impurities in Ampoules
    LIANG Minglianga,HUANG Meizhenb,SUN Zhenhuaa,JI Yuna
    2014, 48 (10):  1357-1361. 
    Abstract ( 994 )   Save

     A method based on the light-blocking theory for detecting impurity particle signals in ampoules was introduced. The optelectronic characteristics of signals of particles contained in ampoules were investigated and analyzed. First, the characteristics of the signal of the pulse amplitude were calculated and simulated based on the scattering theory and large particle light-blocking conditions, respectively. Next, the impact factors of particle diameter, area of detector, beam width and wavelength were investigated. In addition, in order to improve the accuracy of the test results, an optimized optical layout based on lens array and photodiode array was proposed and confirmed by experiment.

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    DOA Estimation of Coherent Signals with Preprocessed Single Snapshot
    MAO Weiping,LI Guolin,XIE Xin
    2014, 48 (10):  1362-1367. 
    Abstract ( 1257 )   Save

    The existing direction-of-arrival (DOA) estimation algorithms of coherent signals using single snapshot limited the types of incident signals or lost array aperture. To address this problem, the novel algorithm was proposed utilizing the crosscorrelation information of receiving single snapshot data to constitute equivalent covariance matrix. Combined with MUSIC or ESPRIT algorithms, the DOA of coherent signals could be estimated. The proposed algorithm was not dependent upon the types of incident signals and avoided the loss of array aperture. The performance of the algorithm is better than those of the existing algorithms under scenarios of low SNR by randomly superimposing a few snapshots. Computer simulation results confirm the effectiveness of the proposed algorithm.

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    16QAM High-Speed Transmission System Using Substrate Integrated  Waveguide-Type Interconnect
    SHEN Limei,LI Xiaochun,MAO Junfa
    2014, 48 (10):  1368-1371. 
    Abstract ( 800 )   Save

    To improve the data transmission rate, in this paper a novel design and implementation of a highspeed interconnect system was proposed based on SIW(substrate integrate waveguide) using hexadecimal quadrature amplitude modulation (16QAM) technique. The inserted loss of the fabricated SIW is appoximately 0.5 dB within a bandwidth of 14 to 28 GHz; the maximum data rate of the 16QAM interconnection system is 20 Gb/s, and a clear eye diagram and constellation diagram is obtained through simulation in ADS(advanced design system). The data rate of the proposed 16QAM highspeed interconnect system is 4 times than that of the conventional system using highfrequency carrier modulate method. Therefore, the proposed 16QAM SIWbased system significantly improves the bandwidth efficiency of SIW and the data transmission rate of the interconnect system.

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    Multipath Delay Estimation Model and Algorithm in OFDM Systems
    CHEN Yajun,PENG Jianhua,HUANG Kaizhi,LUO Wenyu
    2014, 48 (10):  1372-1377. 
    Abstract ( 833 )   Save

    The precision of the TOA (the time of arrival)  estimation is low because it underutilizes the time-frequency characteristics in OFDM (orthogonal frequency division multiplexing) systems. To solve this problem, in this paper, a FDP-MDE (multipath delay estimation based on frequency domain phaseoffset) model was proposed. Besides, a GJ-TDE (grouped joint time delay estimation) algorithm was proposed according to the actual features of the LTE system. First, the time domain signal  was converted into the frequency domain signal. Then, it was sampled into the low-dimensional received signal matrix groups, which were used to estimate the time delay. Finally, the mean of all the delay estimation was taken as positioning. The simulation results show that the root mean square error (RMSE) of the GJ-TDE algorithm is 5.503 4 m smaller than that of the synchronization Mensing algorithm when the SNR is 0 dB and the sampling interval is 8.

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    Differential Cyclic Shift Keying Spread-Spectrum Underwater Acoustic Communication Based on Passive Time-Reversal
    JING Lianyou1,HE Chengbing1,HUANG Jianguo1,MENG Qinwei2,ZHANG Qunfei1
    2014, 48 (10):  1378-1383. 
    Abstract ( 1042 )   Save

     Accurate synchronization is more difficult in the time-variation channel. Conventional cyclic shift keying spread spectrum suffers performance impairment from timing errors in underwater acoustic communications. To solve this problem, a differential cyclic shift keying spread-spectrum underwater acoustic communication technique based on passive time-reversal was proposed. The proposed method requires only “coarse” synchronization at the symbol level. The passive time-reversal can suppress the inter-symbol interference caused by multipath. Lake experiment results show that the proposed method has no bit transmitting error at 1.8 km range; After adding the noise collected at the test, the BER is at 10-4 when SNR is -8 dB with the 5/4 shift units time error.

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    Performance Analysis of Detection Algorithm for Follower Noise Jamming in Rayleigh Fading Channel
    YAN Yunbin,WANG Yongchuan,TIAN Qingmin,LI Yongke
    2014, 48 (10):  1384-1388. 
    Abstract ( 811 )   Save

    Abstract: The detection performance of follower noise jamming (FNJ) for frequency hopping(FH) communication was analyzed in the Rayleigh fading channel. The detection performance of single hop was studied in the AWGN (Addive White Gaussian Noise) channel using the cooperative spectrum sensing in cognitive radio (CR). The detection probability and false alarm probability in the Rayleigh fading channel were deducted. Besides, the detection performance of FNJ in the Rayleigh fading channel was obtained using the “k out of n” rule. The simulation valified the results of theoretical analysis.

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    Hierarchical Memory Optimization Based on Coarse Grain Reconfigurable Architecture for Multimedia Application
    CAO Peng,MEI Chen,LIU Bo
    2014, 48 (10):  1389-1393. 
    Abstract ( 966 )   Save

    In order to optimize the data flow of coarse grain reconfigurable architecture REMUS-II(Reconfigurable Multimedia System2) for high performance media decoding, a novel memory sub-architecture of on-and off-chip memory was proposed by analyzing the data access pattern for multimedia application. For on-chip memory, the 2Ddata and transpose transfer technique was employed to improve the data transfer efficiency by 69.6% and 15.1% on average, respectively. For off-chip memory, the block buffer was implemented to reduce the reference frame accesses with a 37% reduction of accessing time on average. With the memory hierarchy optimization, REMUS-II can achieve real-time H.264 high profile and MPEG2 high level decoding with a definition of 1 980 pixel×1 080 pixel at 200 MHz clock frequency.

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    Packet Delay Estimation with Minimum Queue Waiting in Asymmetric Network
    CHEN Lei,ZHU Tianlin,LIU Feng,WANG Wei
    2014, 48 (10):  1394-1399. 
    Abstract ( 993 )   Save

    To solve the problem of the deterioration in precision time protocol (PTP) synchronization performance caused by uncertainty queue waiting in packet transmission, this paper proposed a packet delay estimation algorithm with minimum queue waiting. Since the packet delay could be estimated with the lucky packets selected from stacks, the PTP synchronization performance would be improved. The boundary conditions of the proposed algorithm was decided by the mean time interval using the selection of “lucky packets” and its expression was deduced. Some meaningful tests indicate that in the asymmetry network, the accuracy of packet delay estimation increases almost 25ns with stability increasing almost 2 orders, and the accuracy of PTP synchronization increases more than onefold with stability increasing almost fourfolds, compared with no optimization.

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    Three-Dimension Path Planning for Unmanned Aerial Vehicle Under Moving Threat
    CHEN Xia,ZHANG Jing,XU Guangyan
    2014, 48 (10):  1400-1405. 
    Abstract ( 917 )   Save

    In this paper, the three-dimension path planning for unmanned aerial vehicle under moving threat was studied. First, the state information of moving threat was predicted by adaptive Kalman filter. According to the relation between heading angle, flight path angle with line-of-sight angles, a mathematical model for controlling track angle was established and a path planning algorithm was presented based on parameter adjustment. Simulations show that the algorithm can assure unmanned aerial vehicle to avoid the moving threat efficiently and quickly.

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    Highly Sensitive Mach-Zehnder Ring Resonator
    CHEN Yao1,2,HE Pengcheng1,BU Tianrong1,DING Yuli1,WEI Yiming1
    2014, 48 (10):  1406-1409. 
    Abstract ( 911 )   Save

    This paper proposed and analyzed a novel ring resonator structure with feedback Mach Zehnder based on the coupled mode theory and transfer matrix, and using the method of normalized transmission  changing with the effective refractive index to analyze the structure. By optimizing the structure parameters  it was found that the proposed structure had a sharp steep  antisymmetric Fano output spectrum. Compared with the traditional microring resonator output curve line, i.e., the symmetry Lorentz spectrum, the output light intensity is more sensitive to  perceive the external environment change. Therefore, the structure has a higher sensitivity and lower detection limit. In the 30 dB signaltonoiseratio(SNR) measuring systems, the detection limit of the structure reaches 10-9 units of the refractive index, which is one order of magnitude lower than the reported 10-8 units of refractive index.

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    Minimum Mean Square Error Vector Precoding Based on Block Diagonalization
    GENG Xuan1,SUN Zuolei1,LIU Feng1,HE Di2
    2014, 48 (10):  1410-1414. 
    Abstract ( 832 )   Save

    For the precoding problem of multi-user multiple input multiple output (MIMO) downlink system, an effective channel having a block diagonal structure by use of block diagonalization (BD) method was proposed. Based on this effective channel, the mean square error (MSE) of transceiver signals was minimized, such that the two parts of perturbation vector, i.e. the perturbation vector expanding constellation and residual interference vector, were derived and thus the total transmit signals and precoding matrix were obtained. The simulation results show that the proposed method outperforms the conventional zeroforcing (ZF) BD method, the zeroforcing BD vector precoding (VP), as well as the regularized block diagonalization and its improved methods.

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    A Novel Method for Realization of NonSinusoidal Orthogonal Modulation System in Time Domain Based on Fourier Transform
    KANG Jiafanga,WANG Hongxinga,b,ZHONG Peilina,CHEN Zhaonana,HU Haoa
    2014, 48 (10):  1415-1420. 
    Abstract ( 821 )   Save

    Abstract: In the application of the non-sinusoidal orthogonal modulation system based on PSWF (prolate spheroidal wave function) in time domain it is difficult to generate PSWF in real-time and complex to realize the non-sinusoidal orthogonal modulation system. Therefore, starting from the Fourier series expansion of PSWF, the relationships between the expansion coefficients and the energy and orthogonality of PSWFs were analyzed. Then, a modulation method based on the inverse discrete Fourier transform (IDFT) and a demodulation method based on the discrete Fourier transform (DFT) were deduced. After that, structures of the modulator and demodulator based on the (inverse) fast Fourier transform (FFT & IFFT) were given. As the idea of Fourier transform was introduced to the realization of non-sinusoidal communication system, the connection between nonsinusoidal communication system and (inverse) discrete Fourier transform was established. This method may provide reference for the study of nonsinusoidal technology.

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    Image Fusion Based on Random Projection and Sparse Representation
    WANG Rui,DU Linfeng,CHEN Junli,WAN Wanggen
    2014, 48 (10):  1421-1427. 
    Abstract ( 890 )   Save

    In order to reduce the computational cost while maintaining the sufficient fusion quality, a novel notion of image fusion approach was explored combining fusion with data compression based on compressed sensing. First, the sensing data was compressed by random projection. Then, the sparse coefficients were obtained on compressed samples by sparse representation. Finally, the fusion coefficients were combined with the fusion impact factor and the fused image was reconstructed from the combined sparse coefficients. Experimental results validate its rationality and effectiveness, which can achieve comparable fusion quality on less compressed sensing data.

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    Traffic Monitoring of Inland Waterways Based on Optic Fiber Sensors
    LI Yang1,CHEN Jingfeng1,JIN Ronghong1,GENG Junping1,LIANG Xianling1,GAO Kan2,WU Bingyan2,CUI Dan3
    2014, 48 (10):  1428-1433. 
    Abstract ( 956 )   Save

    Based on a set of optic fiber sensors, an algorithm was proposed to count ships in inland waterways by combining the threshold of sound energy and the time-frequency characteristics of strong line spectrums, which solved the counting problem emerged when a number of ships went through the monitored water area in parallel. The processing results of a piece of 45 minutes long sound pressure data proved the effectiveness of this algorithm.
     

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    Algebraic Attacks on Trivium-Like Stream Ciphers
    SUN Wenlong1,GUAN Jie1
    2014, 48 (10):  1434-1439. 
    Abstract ( 1076 )   Save

    Trivium stream cipher is one of the finalists of European eSTREAM project. In order to have a better study of the design ideas of Trivium, two revised Trivium algorithms were typically chosen together with Trivium as the targets. The recovery of internal state was converted into the SAT problem to analyze the security of Trivium-like stream ciphers against algebraic attacks. Six guess strategies were tried, and then the equation systems were fed to MiniSat2.0. Finally, some suggestions for the security of Triviumlike stream ciphers against algebraic attack were given according to the results.

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    Automation Technique, Computer Technology
    A Method of Risk Assessment Based on Flexible Similarity Measurement and Possibility Skewness
    WANG Xiaoxia,YANG Fengbao,LIN Suzhen,SHI Dongmei
    2014, 48 (10):  1440-1445. 
    Abstract ( 854 )   Save

    Abstract: Aimed at the poor risk assessment effect resulted from index information asymmetry and the fact that the existing similarity measurement method can only deal with linear information, this paper proposed a risk assessment method based on flexible similarity measurement and possibility skewness. First, a method for flexible similarity measurement was proposed based on expanded generalized fuzzy number as adaptive fuzzy number, and its basic properties were proved. Second, the asymmetry of the index information was analyzed, and a matrix of possibility skewness was built. Finally, a risk assessment model was established by using flexible similarity measurement and possibility skewness, and the validity of the method was proved by taking practical example of tailing dam.

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    Structural Optimization of Satellite Based on MultiObjective Collaborative Optimization Algorithm
    YANG Lili1,CHEN Changya2,WANG Deyu1
    2014, 48 (10):  1446-1450. 
    Abstract ( 1121 )   Save

    Abstract: Aimed at the time-consuming problem of multiobjective and multiconstrained structure optimization of satellite system, a multiobjective collaborative optimization model was proposed for satellite structure. A COPE(collaboartive optimization and parto explorer) combinatorial optimization method was presented by combining collaborative optimization with the global multiobjective optimization algorithm, and taking some improvement measures in view of the defects of collaborative optimization. The multiobjective optimization of a satellite was taken as an example, where iSIGHT was used to conduct the multiobjective optimization of satellite structure. Then, the Pareto optimal set was obtained by adopting COPE. The results show that the multiobjective collaborative optimization model can simplify the complexity of optimization problem, and the COPE combinatorial optimization method based on the approximation model has good accuracy and efficiency. This method provides a certain reference value for similar complex structure optimization problem.

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    Optimization  of Multidisciplinary Reliability Design Based on Interval Uncertainty
    FANG Pengya,CHANG Xinlong,HU Kuan,ZHANG Xiaojun
    2014, 48 (10):  1451-1456. 
    Abstract ( 1109 )   Save

    Abstract: Aimed at the problem resulted from the direct integration of random reliability-based design and multidisciplinary design optimization that the random reliability method cannot solve the problem with limited uncertainty information and the nested structure of direct integration has low computational efficiency, the model of interval uncertainty based multidisciplinary reliability design was presented, in which the uncertainty with limited information was described with interval variable and the reliability of multidisciplinary system was measured with non-probabilistic reliability index. Moreover, to improve the efficiency, the performance measurement approach was applied to reduce the computational cost of the reliability analysis and the sequential optimization and reliability assessment method were applied to simplify the computation process through decoupling the 3-layer nested structure into sequential deterministic multidisciplinary design optimization and multidisciplinary reliability analysis. A numerical example was used to test the feasibility and effectiveness of the method. The results show that IDF has higher efficiency than MDF.

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    Approximate Top-k Query Algorithm for Spatial Keyword in Sensor Networks
    ZOU Zhiwen,LI Qiao,KOU Aijun
    2014, 48 (10):  1457-1460. 
    Abstract ( 817 )   Save

    Abstract: In this paper, a Top-k query algorithm based on node pruning rules was proposed. The concept of a set dominate region and pruning rules were defineded. As the position of users change in the dynamic set dominate region, the nodes of wireless sensor networks were pruned which conformed to pruning rules. The statistical sampling theory was used to design an approximate Top-k query algorithm based on spatial keyword. Experiments on two real datasets were made to validate the effect of the algorithm. The results show that the algorithm meets the needs of users in sensor network environment and it has an advantage of low energy consumption compared to the incremental border distance (IBD) algorithm and query algorithm of spatial keyword based upgraded MWVoronoi region (MSK-uvr).

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    Preventive Maintenance Policy of Cluster Tools Based on Markov Process
    QI Faqun,ZHOU Binghai
    2014, 48 (10):  1461-1467. 
    Abstract ( 662 )   Save

    Abstract: In order to ensure the reliability of cluster tools in semiconductor wafer fabrications, a Markov processbased preventive maintenance policy was presented considering the economical efficiency. First, a state transfer model was established by applying the method of combining major maintenance and minimal maintenance,  taking into account the random failure and degradation failure modes. Then, the steadystate probability for each state and transition probabilities among states were calculated based on the Markov theory. After that, the optimal maintenance policy was obtained through the policy iteration algorithm and the Markov decision theory. Finally,numerous experiments were  conducted. The results indicate that the proposed preventive maintenance policy is effective and feasible.

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    Non-Contact Measurement for Outside Screw Based on a Modified  Sub-Pixel Edge Detection Algorithm of Zernike Moments
    CAI Yan1,YE Lianxiang2,SUN Dawei1,TIAN Hua2,ZHU Junjie1,HU Zhiyun2
    2014, 48 (10):  1468-1472. 
    Abstract ( 149 )   Save

    Abstract: In order to improve the measurement accuracy of screw using the modified edge detection method and the optimized algorithm of characteristic parameters, a first-order derivative model combined with the edge gray threshold was proposed based on the subpixel edge detection algorithm and the Zernike moments. A new method was designed to calculate characteristic parameters, including pitch diameter and thread angle. The results show that the modified algorithm has improved the precision and adaptive capacity of the measurement method.

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    An Improved UPF Object Tracking Algorithm Based on Multi-Feature Fusion
    LI Xiaoxu1,DAI Bin1,CAO Jie1,2
    2014, 48 (10):  1473-1478. 
    Abstract ( 132 )   Save

    Abstract: To solve the robustness problem and poor use of the latest measurement information in object tracking with single feature, this paper proposed an improved UPF tracking algorithm based on multifeature fusion. First, the algorithm was improved by using the UPF algorithm with the scaled minimal skew simplex sampling strategy and the IKF algorithm. Then, the uncertain measurement method was adopted to fuse the color and texture features of the object and track the object with the framework of the improved algorithm. The simulation results show that the proposed algorithm improves the tracking accuracy, has a better effect on tracking the object under complex scenes accurately and tracks the occluded object effectively.

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    Control of Hopf Bifurcation in a Fluid-Flow  Model in Wireless Networks
    XU Chao1,2,ZHOU Yunlong2,WANG Yang2
    2014, 48 (10):  1479-1484. 
    Abstract ( 114 )   Save

    Abstract: Aimed at the Hopf bifurcation problem of a fluid-flow model for the congestion control in  wireless networks, comparative experiments of three kinds of control method were conducted in this paper. By choosing the communication delay as a bifurcation parameter, it was proved that with three kinds of the controller, the critical value of bifurcation  were changed and the stable region were enlarged, and the Hopf bifurcation of the system was delayed. Numerical results verified that the performance of the Hopf bifurcation with delay feedback controller, the performance of the hybrid controller and the performance of the state feedback controller in a wireless network were different; the state feedback controller can most effectively control Hopf bifurcation of the system, followed by the hybrid controller.

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    Anti-Interference of Neuronal Network Synchronization
    CHANG Xiaolonga,DING Guoliangb,LOU Jiananc
    2014, 48 (10):  1485-1490. 
    Abstract ( 136 )   Save

    Abstract: To understand the underlying mechanism of reliable neural information processing in noise, the neuronal model was adopted to build neuronal network and its activities of synchronized firing and characteristics of antiinference were analyzed. The degree of synchronization and ability of antiinterference were quantified and the relation between them was discussed. The simulation results show that the scales of neuronal network and strength of coupling have remarkable effects both on synchronization and antiinterference; under some conditions, the ability of antiinference is almost linear with the degree of neuronal synchronization. Therefore, it is concluded that neuronal synchronization can reduce noise and execute reliable information coding and processing in the brain.

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    A Lightweight Local Authentication Mechanism for Network Mobility in Proxy Mobile IPv6 Network Based on Security Associations
    TANG Hongbo1,TANG Wei1,2,CHEN Long1
    2014, 48 (10):  1491-1497. 
    Abstract ( 119 )   Save

    Abstract: A local light authentication mechanism based on security associations (LLAMSA) for network mobility (NEMO) in Proxy Mobile IPv6 Network was proposed. Based on the architecture of authentication, and authorization and accounting (AAA), the mechanism of optimized routing policy and extended security association was used to integrate authentication and address registration process, making the handover and authentication process to be limited in the local PMIPv6 domain. The performance analysis shows that LLAMSA not only implements the mutual authentication but also resists tamper attacks to protect the address registration information, improving the safety of NEMO. The performance of computation cost and authentication delay is better than existing mechanisms.

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    A Group Key Agreement Scheme for QKD Networks
    SU Jinhai,LUAN Xin,GUO Yixi,ZHAO Hongtao
    2014, 48 (10):  1498-1502. 
    Abstract ( 109 )   Save

    Abstract: In QKD(quantum key distribution) networks, in order to serve the multicast communications among multiple users better, based on the special application background of quantum key generation in pairs, a group key agreement model was built and a group key agreement scheme based on clustering structure and binary code was presented. This scheme consumes a small amount of end-to-end quantum keys, and then obtains a consistent set of keys via security consultation. When new members join or old members leave, the key update is fast and easy. Analysis shows that the scheme has good security.
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