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Table of Content

15 April 2014 Volume 27 Issue 4
  
    Articles
    Research on DOA Estimation Based on MUSIC Algorithm in TD-SCDMA System
    WANG Weimeng,JIAO Ronghua,ZOU Decai,LI Xiaohui
    . 2014, 27(4):  1. 
    Abstract ( 1094 )   PDF (646KB) ( 1441 )  
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    Aiming at the low resolution of traditional DOA estimation methods and the inability for existing Multiple Signal Classification (MUSIC) algorithm to apply to TD-SCDMA system,this paper makes a study of DOA estimation method based on MUSIC algorithm in TD-SCDMA system.With the Uniform Circular Array (UCA) model of TD-SCDMA system preprocessed,the basic MUSIC algorithm and root-MUSIC algorithm of DOA estimation are derived for TD-SCDMA system.The factors affecting the resolution of DOA estimation are also analyzed.Simulation results and analysis shows that the root-MUSIC algorithm has a higher resolution than the basic MUSIC algorithm.

    A Cluster-Hungarian-based OFDMA Subcarrier Allocation Algorithm
    ZHANG Xu,CAO Jinjin,SONG Xi,REN Chao,DUAN Shigang
    . 2014, 27(4):  5. 
    Abstract ( 805 )   PDF (671KB) ( 693 )  
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    The paper proposes a cluster-Hungarian-based subcarrier allocation method for the OFDMA wireless communication system.Maximum correlation is used to cluster the resources with certain similarity,and the resources are allocated to the same users for the subcarriers to provide maximal link rates.The simulation results show that this method can achieve maximal user rates and the optimal performance.

    A Low Power Time Synchronization Algorithm for the Multi-hop Wireless Sensor Networks
    SONG Xuwen,LI Xiaowei,SHEN Dongdong,CHEN Chen
    . 2014, 27(4):  9. 
    Abstract ( 845 )   PDF (666KB) ( 891 )  
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    The low-power and high-precision time synchronization for wireless sensor networks is essential.This paper focuses on a high-precision time synchronization algorithm FTSP (Flooding Time Synchronization Protocol) and finds that in multi-hop networks the time synchronization process generates much redundant information because all of the nodes in each hop must broadcast time synchronization packets.In order to reduce power consumption,this paper proposes a novel approach which selects some nodes called edge nodes by adjusting the transmission power in each hop and allows them to complete time synchronization for the next hop.The other nodes only receive time synchronization packets.Finally,the improved algorithm is carried out on OMNet++ simulator and the results show that the improved algorithm can effectively reduce the energy consumption of the whole network.

    Adaptive Polynomial Pre-distortion Technology Based on the Genetic Algorithm
    QIN Zhenliang,ZHANG Tao,LIU Yanping,LIU Zhihua
    . 2014, 27(4):  12. 
    Abstract ( 862 )   PDF (706KB) ( 892 )  
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    The paper presents an adaptive genetic algorithm based on polynomial pre-distortion compensation method.The basic principle of such polynomial pre-distortion technology is to use simulated evolutionary-like algorithm to approximate the objective function,treat solving parameter identification,and then get the polynomial pre-distortion model.The algorithm has good convergence and global robustness and with high computational efficiency and provides a new approach to the digital pre-distortion adaptive algorithm.The adaptive genetic algorithm is applied to the design of power amplifier linearization and simulation,and the results show that simulated evolution using genetic algorithm class has obvious amplifier distortion suppression effect.

    Study on the Blocking Problem of Improved PCMA Protocol
    WANG Yue
    . 2014, 27(4):  16. 
    Abstract ( 802 )   PDF (480KB) ( 641 )  
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    The blocking problem in Media Access Control (MAC) protocols of Ad Hoc networks is analyzed.an improved PCMA protocol,DBT-PCMA,is proposed after an analysis of the diversity of blocking problems in different protocols.The solutions to the blocking problem in PCMA protocol and DBT-PCMA protocol are discussed.The analysis shows that the proposed protocol can reduce the odds of the blocking problem efficiently,and improve the system throughput.

    A Wideband Digital Amplitude and Phase Errors Correction Algorithm
    LI Guoliang
    . 2014, 27(4):  19. 
    Abstract ( 951 )   PDF (595KB) ( 730 )  
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    The amplitude and phase errors cause the frequency-dependent amplitude and phase differences of channels in Wideband Digital Array Radar (WDAR).Two algorithms in time-domain and frequency-domain are introduced.The diagonal weighting matrix depends on the frequency of the diagonal factor.A modified algorithm in frequency-domain based on least squares fitting method is presented.The simulation experiment shows the performance of the algorithms in time-domain and frequency-domain and the impact to the performance of the digital beam forming (DBF),which confirms the accuracy and feasibility of the improved frequency-domain algorithm.

    An Improved ECDSA Based on the Fast Scalar Multiplication Algorithm
    YAN Lin,LU Chen
    . 2014, 27(4):  23. 
    Abstract ( 706 )   PDF (577KB) ( 663 )  
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    The computational scalar multiplication kP is the key to ECC fast realization and the hotspot of ECC systems research.This paper introduces the fast scalar multiplication algorithm of Montgomery,reviews the double scalar multiplication for kP+lQ proposed by Bai,and improves it after an analysis of its limitations.Based on the improved algorithm,the paper proposes a two-subsections algorithm and applies them into the ECDSA.The proposed scheme proves efficient.

    A Low Complexity Algorithm for Reducing OFDM System PAPR
    XU Linbo
    . 2014, 27(4):  27. 
    Abstract ( 724 )   PDF (508KB) ( 579 )  
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      SLM (Selected Mapping) is an effective algorithm to reduce Peak to Average Power Ratio (PAPR) of OFDM (orthogonal frequency division multiplexing) signal without distortion.But this scheme needs to dispose of U paths of IFFT,which increases the amount of computation and reduces the signal transmission rate.This article gives an improved algorithm based on SLM,which is called Random Screening SLM (RSSLM).The proposed algorithm fulfills the selection before the FFT modules.On the basis of decision threshold,the scheme only selects the one sequence with the best randomness to transmit to IFFT modules,thus a much lower complexity than that by SLM method.The improved scheme enhances the transmission rate of signal,and greatly decreases the PAPR of OFDM signals.

    An Image Fusion Algorithm Based on NSCT and PCNN
    HU Yucheng,WANG Chuangxi
    . 2014, 27(4):  30. 
    Abstract ( 988 )   PDF (774KB) ( 614 )  
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    An image fusion algorithm is proposed based on the shift-invariant,multi-scale and multi-directional NSCT and the pulse coupled neural network PCNN.First,a multiscale decomposition of the source image is performed with NSCT,and then with low coefficient using improved regional energy integration rules and the high frequency coefficients using PCNN fusion rule,the final fused image is obtained through NSCT inverse transform of the fused coefficients.Experimental results show that this method better retains useful information in the original image,and improves the quality of the fused image.

    A Description Method for the Complex System Qualitative Model
    ZHANG Jie
    . 2014, 27(4):  34. 
    Abstract ( 732 )   PDF (860KB) ( 640 )  
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    Hardly can the existing modeling methods meet the demands of constructing the complex system with qualitative attribute that presents a trend towards uncertainty and nonlinearity.Thus,a description method of complex system qualitative model (QMDM) is put forward.Based on the combination between the qualitative simulation theory and the extension of UML component diagram,sequence diagram and state diagram,QMDM visually expresses the modeling process of qualitative model.The component diagram gives a static expression of qualitative constraint relations including in the qualitative model,while the sequence diagram and state diagram dynamically convey the time sequence as well as state transition embedded in the qualitative model.In addition,the formal definition of QMDM is given to provide convenience for later validation.Finally,the research achievements find a preliminary application in the air conditioning refrigerating system.

    Trajectory Analysis of Six Degrees of the Freedom Manipulator in Refrigerator Energy Detection
    ZHANG Chang,TANG Lijun,WU Dingxiang,HE Huiyong,SI Niu,LI Tao
    . 2014, 27(4):  41. 
    Abstract ( 831 )   PDF (689KB) ( 609 )  
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    This paper proposes a method for six degree of freedom manipulator to control refrigerator switch-door to deal with the errors caused by manual switch-door in refrigerator energy detection.This method analyzes the trajectory of manipulator switch-door in refrigerator energy detection.The position and orientation of each joint movement is analyzed by setting up the model of the manipulators to get the angle of each manipulator joint.Simulation analysis verifies the accuracy of the manipulators switch-door movements.

    Remote Electric Parameter Measurement Based on ARM and Ethernet
    WANG Qidong,YAO Xiaotong,WANG Jirong
    . 2014, 27(4):  44. 
    Abstract ( 822 )   PDF (683KB) ( 720 )  
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    In view of the inconvenience in present power and charging management,this paper studies the remote electric parameter measurement based on ARM and Ethernet technology.The technology is mainly used for collection and storage of electrical parameters.The main controller uses the 32-bit ARM microprocessor STM32F103V,together with the PC display parameter interface hardware design.The PC adopts the LabVIEW DataSocket technology to realize the display function.The combination of upper and lower position machine achieves electric energy metering and convenient management.

    A New Mining Cable Selection Method Based on Matlab
    QIU Feng,GONG Maofa,YANG Ningxia,LIU Bingqian,GE Huiting,LIN Yuqing
    . 2014, 27(4):  48. 
    Abstract ( 750 )   PDF (635KB) ( 634 )  
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    This paper is aimed at the practical problems in mining cable selection.Based on the optimization theory,the MATLAB Optimization Toolbox programming is proposed as the solution,and with the help of practical data,the method is realized on the computer.This method can simplify the cumbersome selecting steps and saves the investment and operation cost.The reliability,safety and economy of mining area power grid operation are also guaranteed.

    Solution to 0-1 Knapsack Problem Based on the Greedy-genetic Algorithm
    YAO Wenjuan,WU Fei,XIA Qian,SHAO Biao,ZHANG Longzhong,LIU Jian
    . 2014, 27(4):  51. 
    Abstract ( 1069 )   PDF (525KB) ( 675 )  
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    A greedy-genetic algorithm is proposed combining greedy algorithms and genetic algorithms.The algorithm constructs a new and better operator than the original one.It not only accelerates the convergence speed but also avoids the local optimum trap of the traditional method,thus improving search efficiency.The computer simulation results show that the greedy genetic algorithm has better approximate solutions than the average genetic algorithms,demonstrating the effectiveness and practicality of greedy- genetic algorithms in solving the knapsack problem.

    A Survey of Fast Handoff in IEEE802.11r WLANs
    WU Fuqiang,CHU Erhu,LI Jun
    . 2014, 27(4):  54. 
    Abstract ( 821 )   PDF (601KB) ( 671 )  
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    The efficient handover in the IEEE802.11 networks is the key requirement for real-time multimedia support in such networks。The handover delay is significantly limited with the Fast Transition protocol introduced in IEEE802.11r amendment。However,the whole handoff process still can not meet the needs of real-time applications.This paper makes a full-scan introduction to the research on fast handoff in Wireless LANs,analyzes the impact of IEEE802.11r amendment in the entire handoff process,and introduces research work on the fast handoff.

    Design and Simulation of a New Pattern Schmitt Trigger Type VCO
    MU Xin,ZHOU Xintian,ZHANG Huihui,JIN Rui,LIU Yueyang,WU Yu
    . 2014, 27(4):  58. 
    Abstract ( 878 )   PDF (606KB) ( 718 )  
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    Traditional Schmitt trigger type VCO has two main problems:the minimum value of input voltage is too high and the maximum value of oscillating frequency is too low.To solve these two problems,this article introduces a Schmitt trigger type VCO with new structure of charging and discharging circuits,and simulates it with the implementation of the 0.18 μm technology.The result shows that the minimum value of input voltage of new VCO has decreased considerably while the maximum value of oscillating frequency has boosted obviously compared with the traditional Schmitt type VCO.

    Design of the Intelligent Multi-input High Power LED Driver Circuit
    ZHANG Ting,WANG Junyong,ZHANG Li,LI Bao,LIU Xingsheng
    . 2014, 27(4):  60. 
    Abstract ( 811 )   PDF (687KB) ( 628 )  
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    The article implements multichannel input LED drive circuit design with the wind,solar energy,electricity based on single-chip Intelligent Control.The wind and solar complementary power generation system can realize maximum power point tracking (MPPT) controlling strategies under different working conditions.The characteristics of wind and solar power generation are displayed using simulated wind-solar energy.The protection measures of wind-solar hybrid controller are improved.The battery charging controlling solutions optimizes the charging process stage by stage to realize the maximum utilization of energy with the intelligent control,thus achieving the best overall performance of drive circuit design.

    Design and Implement of a Portable Logic Analyzer
    XIONG Ming,ZHAO Qinchuan
    . 2014, 27(4):  64. 
    Abstract ( 673 )   PDF (682KB) ( 878 )  
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    This article describes a 16-channel portable logic analyzer.Sampling is performed through the FPGA and high-speed data buffer,the data is sent to the computer via the USB controller chip and FPGA cooperative control through the USB interface on the PC display,thus simplifying the previous circuit logic analyzer hardware and reducing the cost and size of the logic analyzer.Emphasis is put on the hardware circuit design.

    Design and Implementation of Miniaturized X-band Dual-channels T/R Module
    LIAO Yuan,WANG Jie,ZHANG Juan,ZHANG Shengchun
    . 2014, 27(4):  66. 
    Abstract ( 777 )   PDF (684KB) ( 751 )  
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    A dual-channels T/R module is presented which adopts MCM technology for miniaturization design.The key circuits and structures are analyzed and optimized by electromagnetic simulation software.The small-size and light-weight features are ultimately realized.And the measured results show that the proposed T/R module exhibits good electrical properties.

    Effect of the Hot Carrier on the Life of the CCD On-chip Amplifier
    WANG Ling,TANG Li,LIAO Xiaohang,REN Liping
    . 2014, 27(4):  69. 
    Abstract ( 627 )   PDF (779KB) ( 689 )  
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    The life of the CCD on-chip amplifiers is studied.The relation between the characteristic parameters of Gm degradation and degradation time is found through hot carrier effect analysis using substrate current model on a tailor-made MOSFET to determine the composition of CCD on-chip amplifier life.The results show that the service life of CCD on-chip amplifiers decreases with the gate length,and the LDD structure can prolong the CCD chip amplifier service life.

    Design of an Integrated Waveguide Diplexer Based on Complementary Split Ring Resonators
    LI Chenjing,ZHOU Yonggang,JIN Yao,LI Fushen
    . 2014, 27(4):  72. 
    Abstract ( 898 )   PDF (754KB) ( 731 )  
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    A novel substrate integrated waveguide (SIW) diplexer with circular complementary split-ring resonators (CSRRs) is presented.The proposed diplexer working in C-band operates below the characteristic cutoff frequency of SIW and two channel filters of this diplexer are nearly 30% smaller than traditional SIW ones.Circular CSRRs,which perform better than square CSRRs at compact structure,are adopted to further reduce the size of channel filters,and a slot is cut between two CSRRs to increase the isolation.A proposed diplexer is fabricated and measured.The measured insertion losses are 1.75 and 1.62 dB in the lower and upper passbands centered at 3.92 and 4.62 GHz.The isolation is higher than 37 dB.A perfect agreement is achieved between the simulation and measurement.
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    Design of A Miniature Anti-vibration Crystal Oscillator
    CHEN Zhongping,XU Shuyi,JIA Yingqian,WANG Zhankui
    . 2014, 27(4):  76. 
    Abstract ( 920 )   PDF (603KB) ( 690 )  
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    The performance of the crystal oscillator is more important now in modern communication systems.This article discusses the phase noise of crystal oscillator under vibration.We choose a miniature isolator for designing an anti-vibration crystal oscillator.The isolator improved the phase noise of the anti-vibration crystal oscillator in vibration.The testing results shows that the phase noise of the miniature anti-vibration crystal oscillator is better than -147dBc/Hz at 1kHz offset frequency and actually providing about 40dB improvement.

    Design of a 20-output Microstrip Wilkinson Power Divider
    CUI Dongnuan,WANG Jianhui
    . 2014, 27(4):  79. 
    Abstract ( 789 )   PDF (839KB) ( 621 )  
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    〗A 20-output Wilkinson power divider at S frequency is proposed.The 20 output ports Power Ratio is 1:1,and the characteristic impedance of input line 50.The structure is drawn by 3D-electromagnetic simulation software Advanced Design System 2009.The result shows that the proposed power divider demonstrates a good performance within the desired frequency range from 2.17 GHz to 2.20 GHz with the return loss less than -18 dB at 1.5 GHz and the output power and phase imbalances about 0.3 dB and 2° respectively.The isolation between the two outputs is with -25 dB isolation for the whole bandwidth.

    Design of a Multi-band Printed Monopole Antenna
    WANG Lei
    . 2014, 27(4):  82. 
    Abstract ( 621 )   PDF (614KB) ( 599 )  
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    A compact printed monopole antenna is proposed for WLAN and WiMax applications.Impedance bandwidths covering 2.4/5.2/5.8 GHz WLAN and 3.5/5.5 GHz WiMax bands are obtained by using a modified dual G-shaped strip.Omnidirectional radiation patterns over the operating bands of a fabricated antenna are obtained,which shows that the antena has great impedance bandwith and good radiation characteristics,and is suitable for multi-band wireless communication applications.

    Application of Power Divider in Phased Array Feed Network
    GONG Yongming,LIU Haoxin,QIU Yun
    . 2014, 27(4):  85. 
    Abstract ( 708 )   PDF (545KB) ( 706 )  
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    This paper introduces the power dividers in the phased array feed network application,which USES a transmitter power by power splitters connected to the antenna array,compared with the traditional one transmitter corresponding connection in antenna array antenna feed mode,mainly has the following advantages:the impedance of the antenna array in the transmitter port have been better features,improved the original traditional pattern due to the coupling of severe may lead to individual array antenna impedance mismatch in so serious that the transmitter can't work normally;can make the antenna array antenna spacing have larger adjustment space,make the antenna array has better scanning features.

    Design of a High-gain Antenna Based on Enhanced Microwave Transmission
    ZHANG Zhimian,DING You,LI Minquan,CHEN Peixin
    . 2014, 27(4):  88. 
    Abstract ( 862 )   PDF (770KB) ( 718 )  
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    A novel planar high gain antenna is presented based on enhanced microwave transmission to meet the needs of antenna gain in communications systems.The proposed antenna is simulated by high frequency simulation software Ansoft HFSS.The measured result shows that the gain of the proposed antenna is 12.9 dB,which is 6 dB higher than that of the conventional antenna.Moreover,due to the design of the annular aperture structure and the corrugated structure,the half power band width (HPBW) is increased by 100 degrees.The performance of the proposed antenna is improved significantly.

    Study of DBF Pointing Angle for Small Inclination and Near-Circular LEO Satellite
    ZHAO Yonghui,FANG Qing
    . 2014, 27(4):  91. 
    Abstract ( 712 )   PDF (681KB) ( 655 )  
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    The beam pointing angle of small inclination and near-circular LEO satellite during open loop tracking of digital beam forming (DBF) is studied.Instead of the classic Kepler elements,improved elements based on the second class of no-singularity elements are proposed and satellite position and velocity in Earth Centered Inertial coordinate are converted into instantaneous orbit elements to avoid the singularity problem which occurs in orbit determination with data fitting.The position of spacecraft and relay satellite are calculated with mean orbit elements obtained by least-square fitting.Finally the computation process of beam pointing angle for DBF is presented.The simulation results demonstrate the accuracy and efficiency of the algorithm.

    A Novel Technique for High/Low Power Switch
    LU Xiaona,LI Jiaying,CHEN Zhihong
    . 2014, 27(4):  95. 
    Abstract ( 712 )   PDF (542KB) ( 643 )  
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    This paper proposes a novel technique for high/low power switch by taking the advantage of the characteristics of the three ports circulator circular according to the high power radar transmitter technical requirements.A PIN diode SPST high-power RF switch suffices to realize high/low power switch by this technique,and the switch need not go through a high power,but reflect a high power,thus greatly reducing the difficulty of implementation.An S-band transmitter is developed using this technology with a power output more than 1 500 W,which successfully realizes high/low power switch,and power capacity and switching speed can satisfy the requirements of design.

    Hardware Design of a Universal Network Downloader Based on FPGA
    WU Jie
    . 2014, 27(4):  98. 
    Abstract ( 702 )   PDF (956KB) ( 846 )  
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    As an important part of the aerospace ground computer detection system,the network downloader plays an important role.This paper describes the overall design of the network downloader with the schematic design of the hardware main modules given,and provides the application of reference for LVDS interfaces,high-speed bus and stacked design in the PCB design to ensure the system hardware reliability.Good performance is achieved in practice.

    Design of a Non-transformer LED Driver Based on TOPS witch
    JIN Yonggao,ZHANG Kehe
    . 2014, 27(4):  101. 
    Abstract ( 697 )   PDF (871KB) ( 652 )  
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    A design of non-transformer LED drive power based on TOPSwitch is proposed.It drives TOPSwitch by current of the load side without transformer and optocoupler,thus greatly reducing the size,weight and costs.Simple in structure is,it can work stably and reliably on a wide voltage range of 180~250 V with constant-current characteristics,and can be widely used to drive 5~75 W of LED lighting.

     Applications of the Smart Home System Based on STM32
    JIANG Yang,LIU Yuhong,HAN Yunjie
    . 2014, 27(4):  105. 
    Abstract ( 771 )   PDF (686KB) ( 843 )  
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    The smart home system adopts STM32F103 as the control core.Users send data to the STM32 by mobile phone or other handheld devices via the bluetooth module,and STM32 processes and sends the received data to the terminal devices via the infrared module to realize the intelligent control of household.The whole system has good anti-interference performance and high reliability,and can be applied to intelligent household applications.

    The Design of Electrocardiogram Acquisition Instrument Based on STM32
    XIE Shun,ZHANG Yibin
    . 2014, 27(4):  108. 
    Abstract ( 1023 )   PDF (692KB) ( 874 )  
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    This paper introduces a scheme of electrocardiogram acquisition instrument based on STM32 processor,the scheme realizes the extraction of weak signal from strong noise environment through the AgCl electrode and a three lead ECG acquisition line,followed by AD620 and OP07 as the core component of the analog front end of the collected ECG signal filtering amplifying,finally digital processing by using STM32 processor,biological signals are clear,stable and can reflect the actual characteristics of the human ECG,and in the LCD real time display,the design is simple and practical,high stability,has certain medical value.

    Design and Implementation of an FPGA-based High-precision Frequency Voltage Conversion System
    GE Yun,WU Ning
    . 2014, 27(4):  112. 
    Abstract ( 923 )   PDF (764KB) ( 747 )  
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    A linear F/V converting system is designed.The pulse frequency signal generated by the sensor is sent to FPGA after being conditioned by the signal conditioning circuit,and then FPGA measures the frequency of the signal.The system precision requirements require a design of Q format fixed-point arithmetic.The measured frequency obtained by the FPGA fixed-point arithmetic is linear with the digital value of DAC which controls DAC7551 output the corresponding voltage.The experimental results show that the system of conversion precision is better than 0.1%.Changing the system design parameters can achieve a more precise frequency signal to the voltage signal conversion.

    Design and Realization of Static Var Generator
    WANG Peng,FU Zhouxing
    . 2014, 27(4):  115. 
    Abstract ( 683 )   PDF (657KB) ( 640 )  
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    Designed a SVG based on DSP TMS320F2812,and the concrete implementation method of the hardware design and software design is given.The theoretical analysis and the Matlab/Simulink simulation results show that the control system has good performance and verifies the effectiveness of the offered design proposal.

    Design of a Vibration Detector Based on the Acceleration Sensor of MMA8451
    WANG Shendi,WANG Zaixing
    . 2014, 27(4):  118. 
    Abstract ( 829 )   PDF (568KB) ( 749 )  
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    MMA8451 is a low-power-voltage micro-machined capacitance full digital sensor capable of detecting three directions of acceleration.A master-slave mode vibration testing instrument is designed based on the high-performance sensor.The paper introduces the whole design idea and composition of the circuit,and gives the application with MMA8451 as the front of the sensor in virtual instrument with the test result.The master-slave mode design not only achieves the intended fuctions,but also gets rid of the dependence on LabView.

    Design of a Bipolar Analog Signal MCU A/D Conversion Circuit
    JIANG Yunzhi,ZHOU Hanyi,ZHAN Xiaoqi
    . 2014, 27(4):  121. 
    Abstract ( 708 )   PDF (464KB) ( 652 )  
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    A/D conversion usually requires the use of A/D converter chip,and the MCU built-in A/D module can only receive unipolar analog signals.This paper introduces a circuit design to enable the A/D converter of Freescale MCU to receive bipolar analog signal.The circuit uses symmetrical design to expand the A/D conversion range,and improve the A/D conversion resolution.

    A Practical Design of an Analog Thermal-control Circuit
    XIANG Xiao,YIN Wei,HUANG Ji
    . 2014, 27(4):  124. 
    Abstract ( 822 )   PDF (636KB) ( 971 )  
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    A practical design of analog thermal-control circuit consisting primarily of operational amplifiers,unijunction transistors and SCR is proposed.,the circuit successfully controls the output power by methods of proportional integral,voltage comparison and phase-shifted triggering,so as to regulate the power of a heating equipment.Due to its high stability and precision,as well as strong practicability,this circuit can be applied in industrial control area.

    Design and Simulation of Base-n Counter Based on Proteus
    SUN Hongxia
    . 2014, 27(4):  128. 
    Abstract ( 754 )   PDF (880KB) ( 921 )  
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    A design of base-n counter based on Proteus Software is put forward.Two kinds of the base-48 counters are designed by load method based on the 74LS163 integrated counter,and simulated with Proteus Software.Results show that Proteus Software can carry out the function of the two base-48 counters.The simulation image is clear,which can verify the design results quickly and accurately.

    Design and Implementation of Blind Recognition of Linear Space-Time Block Codes Based on DSP
    LIU Xiaoguang,DONG Yang,QU Qian,WANG Bing,DENG Jie
    . 2014, 27(4):  131. 
    Abstract ( 772 )   PDF (691KB) ( 656 )  
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    This paper presents the design and implementation of a novel MIMO system space-time coding blind identification method based on TigerSHARC TS201S.The design is capable of blind identification empty encoding under non-cooperative conditions by the use of the different lag correlations of space-time coding in time diversity and space diversity.After pre-whitening and delay-dependent calculation,the antenna reception signals are output using the code word table.Tests show that the system is stable and easy to implement with high accuracy of space-time encoding blind identification.

    Design of a Dual Host Embedded System Interconnect Based on RapidIO
    LI Peng
    . 2014, 27(4):  135. 
    Abstract ( 753 )   PDF (738KB) ( 761 )  
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    The development of distributed parallel computing puts high demands on the Internet technology in embedded system.RapidIO can provide high performance interconnection between chip to chip,board to board,with higher transmission efficiency than PCIE and Gigabit Ethernet.The paper presents a schematic design,hardware design and software driver of system interconnect with double host based on RapidIO,and proposes a verification scheme for the function design and capability of system interconnect.The system is very stable and reliable,and serves as a good solution to the new generation of high performance embedded system.

    Design and Implementation of SMS4 Encrypted Communication on Chip Based on the Programmable System
    ZHU Yong,CUI Qiangqiang
    . 2014, 27(4):  138. 
    Abstract ( 726 )   PDF (1166KB) ( 572 )  
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    This paper is intended for industrial,commercial and consumer electronic device encryption on serial communication.SMS4 algorithm for serial communication on hardware optimization techniques are designed and implemented based on the research into the SOPC hardware and software architecture,controller IP technology,and software technology of the SMS4 encrypted communication.Non-128 plaintext encrypted transmission data control technology and 128 bits transceiver technology based on eight asynchronous serial data pattern have been greatly advanced.The encrypted communications SOPC based on SMS4 improves the encrypted communication capabilities with independent and controllable encrypted communication core algorithm.

    Research on and Implementation of the Visual Image Processing Algorithm Based on FPGA
    ZHAO Bei
    . 2014, 27(4):  143. 
    Abstract ( 702 )   PDF (726KB) ( 665 )  
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    In order to efficiently improve the image definition and resolution of multi-screen splicing display system in video supervision,a real-time video image processing algorithm based on FPGA is proposed.Firstly,the overall structure of the system and video image cache and image segmentation in FPGA module are introduced.Then the bilinear interpolation algorithm is presented according to video display requirements.Simulation by ModelSim shows that the algorithm does conform to the requirements of multi-screen splicing display system.

    Automatic Parking Lines Detection and Recognition for Parking Assist System
    LU Guiming,YANG Litao,LI Junxia
    . 2014, 27(4):  146. 
    Abstract ( 799 )   PDF (1190KB) ( 802 )  
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    This paper describes a fully-automatic method for recognizing parking lines based on a 360-degree panorama bird's eye view image which is gaining popularity in parking assist system.With the effect of illumination on the outcome of image processing in consideration,the pre-processing is operated on the image firstly.Then an adaptive Canny edge detection technology based on the image median and Hough Transform is used.Finally,utilizing the priori knowledge about the characteristics of marking lines to constrain the outcome of Hough Transform,we realize the recognition of marking lines.Experiments on the actual image show that proposed method successfully recognizes the most parking lines,and demonstrated a detection rate of 94.2%,which proves the effectiveness and robustness of the proposed method.

    Research on ThinkPHP Framework Based on the Mode of MVC
    WANG Junfang,LI Yinfeng,WANG Chi
    . 2014, 27(4):  151. 
    Abstract ( 1150 )   PDF (724KB) ( 890 )  
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    The software design paradigm MVC is mandatory to make the application of the input,processing and output separately so as to achieve the division of functions of the software system.At present,PHP framework is widely used,and most of them are based on the mode of MVC.ThinkPHP is an open source PHP development framework,which is born to simplify the application development of enterprise and the quick application development of Web.MVC in ThinkPHP provides a quick development method,so that developers can quickly develop a stable business website.This paper introduces the mode of MVC and the research into its application in ThinkPHP framework.Finally,a detailed description of a student mark management system is given as an example.

    An Algorithm of Good Illumination Robustness for Detecting and Tracking Moving Gestures
    LI Zhiming,ZHANG Qi,WU Xia
    . 2014, 27(4):  154. 
    Abstract ( 762 )   PDF (1034KB) ( 498 )  
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    In digital image processing,motion target detection is an important premise.An effective moving gesture detection and tracking algorithm is proposed for the variability of light of the actual environment.The three frames difference algorithm is combined with Camshift moving target tracking algorithm,the single Gaussian modeling algorithm and self-adaptive threshold extraction algorithm to solve the problem that traditional frames difference algorithms cannot apply to complex changes in light.The Camshift tracking algorithm is used to track the gesture,and a realtime Gaussian model is built to adapt automatically to the changes in light.Experimental results demonstrate that the algorithm can detect and track the moving gesture and avoid the influence of the changes in light effetely.

    Transmission of Transmission Line Monitoring Images Using Compressed Sensing
    YAO Jia,TANG Guohong,CHEN Ling
    . 2014, 27(4):  159. 
    Abstract ( 825 )   PDF (702KB) ( 549 )  
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    One of the most important ways to discover the dangerous points of transmission lines and monitor surrounding weather conditions is the condition monitoring of transmission lines.Since transmission lines run across fields and maintains,only hand communication mode can be adopted to transfer video surveillance imagery in the area not covered by communications networks.In order to meet the bandwidth constraint,the compressed sensing method is introduced to perform compression and transmission on surveillance imagery.In addition,according to the characteristics of DSP memory's limitation,surveillance imagery is divided first and then compressed again for reducing the memory of image compression.Therefore,based on signal received from monitoring host side,the gradient project algorithm is applied to reconstruct surveillance imagery for the operating crew to get comprehensive understanding of the line's dangerous points in surveillance center and take measures to reduce accidents to manageable proportions.

    Security System Based on Power Line Carrier Communication and Dynamic Image Detection
    ZHOU Feihao,YANG Yanxiang,LIU Liang,DENG Qiang
    . 2014, 27(4):  162. 
    Abstract ( 692 )   PDF (644KB) ( 394 )  
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    This paper proposes a security system based on power line carrier communication and dynamic image detection with the advantages of low cost and high reliability.The drawbacks of the traditional security systems are firstly analyzed.And then we illustrate the integrated design of the proposed system.When a dynamic image emerges,the proposed system can adaptively capture and then process the image.After that the processed information is transmitted by the existing power line carrier communication.The design of each module is also described in detail.Finally,the advantages of the system are summarized.

    Real-time Monitoring Requirements and Implementation of the Center Computer
    SHI Jufeng,TONG Yan,ZHU Dan
    . 2014, 27(4):  165. 
    Abstract ( 517 )   PDF (624KB) ( 402 )  
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    The performance monitoring system software design requirements in real-time performance and reliability of the central computer system are analyzed.quantitative testing of the real-time performance of multi-process,multi-threaded highly concurrent systems and visualized monitoring of the running status of the central computer system monitoring software are realized by the design of multi-process and multi-threaded module-level-specific monitoring methods.The practical application shows that the real-time monitoring software system can meet the demand of the central computer system for real-time monitoring with reliable operation.

    An Improved Method for Software Process Quality Metric
    ZHANG Weiyong,ZOU Beiji
    . 2014, 27(4):  168. 
    Abstract ( 775 )   PDF (521KB) ( 371 )  
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    This paper proposes an improved method for software process quality metrics for measuring and analyzing software process effectively to produce high quality software products.By this method,the software process is divided into five stages:software requirements,design,coding,testing,and operating maintenance,and each stage is divided further into a number of qualitative factors from the two different angles of commonness and individuality.The quality factor is evaluated by the multi-level fuzzy synthesis evaluation method.Finally the validity and rationality of this method are verified by an real case.

    Analysis and Control of False Alarm of NAMP in Non Avionic System
    HU Shanwei
    . 2014, 27(4):  171. 
    Abstract ( 622 )   PDF (585KB) ( 494 )  
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    The fault of false alarm of the NAMP in non avionic systems is analyzed.Corresponding protections and measures are proposed in light of the disadvantages of present false alarm control for the NAMP system to perform well.

    Review of the Genetic Algorithm for Nonlinear Equations
    WU Long,REN Hongmin,BI Weihong
    . 2014, 27(4):  173. 
    Abstract ( 992 )   PDF (1006KB) ( 895 )  
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    This paper puts forward a summary of researches on solving nonlinear equations by genetic algorithms.The integrated use of various genetic strategies and the effective combination of genetic algorithms and traditional iterative methods or other intelligent optimization methods are discussed.It is found that the parallel genetic algorithm is the key to solving nonlinear equations by genetic algorithms.The future research directions are also discussed.

    Structure Learning Methods in Bayesian Network Application
    ZHANG Xiufang,TANG Xingjia
    . 2014, 27(4):  179. 
    Abstract ( 735 )   PDF (648KB) ( 423 )  
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    Bayesian network is the graphical model used to describe potential dependencies between uncertain variables.Structure learning is the core of Bayesian network learning.The effective learning methods and algorithms of structure learning are the foundation of constructing Bayesian network.In this paper,we summarize the present achievement on Bayesian network structure learning,with a thorough analysis of their complexity and application presented and some key aspects and main idea of the methods pointed out.The summary is helpful in selecting proper methods in practical applications.

    Application and Correlated Color Temperature of LED
    YANG Xiaohui,ZHAO Hongdong,ZHANG Qin
    . 2014, 27(4):  183. 
    Abstract ( 675 )   PDF (790KB) ( 612 )  
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    LED is widely used by its unique advantages.Therefore,the reliability of LED is extremely important.The correlated color temperature (CCT) is an important parameter of reliability.This paper describes the advantages and applications of LED.Curve fitting is performed for CCT by Fourier,Gaussian,Multi-form,Sinusoidal approximation and cluster analysis is made by K-means clustering,text clustering and FCM clustering.It provides great convenience for the research of reliability and screening of devices.

    Things Technology in the B2C E-commerce Distribution Transportation Applications
    ZHENG Nan
    . 2014, 27(4):  186. 
    Abstract ( 732 )   PDF (689KB) ( 527 )  
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    In recent years,with the continuous development of e-commerce,traditional logistics model has been unable to meet current business needs,establish and improve the transport vehicle real-time dynamic monitoring system,the whole process of transport vehicles and cargo condition monitoring is this urgent problem.Things technology will be able to solve this problem,significantly improving vehicle cargo during transport security and reliability.This paper first describes things related technologies,focusing on networking technology in the distribution and transportation of B2C e-commerce application design and implementation capabilities,the final analysis of things the impact of technology on the e-commerce model.

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