Editor in chief:Prof. Sun Shenghe
Inauguration:1980
ISSN:1002-7300
CN:11-2175/TN
Domestic postal code:2-369
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2015, 38(5):1-6.
Abstract:The application based on composite scattering of the actual sea surface with the target below of it demand in ocean engineering, radiation calibration and underwater target detection etc. The application based on composite scattering of the actual sea surface with the target below of it demand in ocean engineering, radiation calibration and underwater target detection etc. The improved onedimensional fractal model is adopted to simulate the actual sea surface, the method of moments is used to study the composite electromagnetic scattering about the sea surface and the trapezoidal crosssection cylinder target beneath it, the curve is abtained by numerical calculation about the complex scattering coefficient changes with the scattering angle, the impact on the composite scattering coefficient is discussed in detail about the surface wind speed, the surface fractal dimension, water temperature, the size and depth of the target and the frequency of the incident wave, the result show that the influence of the surface wind speed, the fractal dimension and the frequency of the incident wave are obvious to the composite scattering coefficient, that the water temperature, the size and depth of the target coefficient have little effect on it.
Jiang Ke , Zhao Chendong , Shan Changshuai , Geng Qiang
2015, 38(5):9-10.
Abstract:With the development of society and increasing of electrical equipment, the original offgrid type wind power generation systems need expansion in some remote areas. In this paper, a novel cascade rectifier device for offgrid type wind power generation is proposed. Using Common DC bus technology, this device can achieve the parallel operation of two generators at the same time, which increases the system capacity. Furthermore, this device can also achieve the maximal wind energy capture of multimachine operation while allowing the duty cycle of power switch device operate in the reasonable range, improving the performance of the system. The simulation results prove the correctness and effectiveness of the device and the control strategies.
Liu Cuiling , Jiang Xu , Wang Jinqi , Qin Binbin
2015, 38(5):11-13.
Abstract:As the downhole has complex and changeful environment, high temperature and high pressure environment has a very important influence on various kinds of instrument performance. The research of the coaxial phase method for water detection instrument high temperature circuit to improve the instrument performance has very important significance. According to the measuring principle ,requirement of the environment and the whole project, designed and optimized the frequency mix circuit. Through the temperature experiment has reached the requirement of heatresistant at 140℃ and reduced the power consumption , eliminated the influence of temperature variation on the mixer measuring phase.
Zhou Zhiliang , Cheng Feng , Zheng Lina
2015, 38(5):14-18.
Abstract:The AM has a wide applications in communication system. At present it is divided into high level and low level AM. In view of traditional implementation method about low level AM, it has the advantage of design flexibility and principle simplicity, but its debugging is complex. It propose the design method of low level AM. According to the magnetization of amorphous metal. the working principle and fabricate technics of voltage controlled inductor are described. The circuit diagram of AM and magnetization inductor are given, its working principle is introduced. Through experimental verification, the AM has the advantage of excellent performance,good linearity and high sensitivity. It has novel innovation and create a new design direction about AM.
Peng Zhangyou , Meng Chunyang , Ren Xiufang , Li Shuai
2015, 38(5):19-23.
Abstract:When Ultra High Frequency Radio Frequency Identification (UHF RFID) tags in dense cloth environment, the work frequency of stacked RFID tags will be deviated by the mutual influence between the tag antennas, and the system read rate will be declined. This paper designed a new type of circular polarization reader antenna, which works in the UHF frequency band, has the characteristics of miniaturization, high gain, and wide band. In this antenna, the main radiation circular patch is connected up and down by four probes to the matching network, which can effectively improve the circular polarization axial ratio bandwidth and work bandwidth of antenna. The simulation results show the antenna has 13% bandwidth of impedance and 5% bandwidth of 3 dB axial ratio, and 9.4 dBi gain in the UHF frequency. In the open environment, we test the tag read rate of intensive multiple RFID tags. The experimental results show that the wide band RFID reader antenna is available.
2015, 38(5):27-32.
Abstract:The data of Windows kernel variables was used frequently on the analysis of memory. But locating these kernel variables was limited by the operating system. Former scholars have proposed some algorithms of Windows kernel variables locating. But after experiments, the result was not satisfactory. With an improvement on precedent algorithms, an algorithm based on virtual address translation was proposed for accurately locating kernel variables. It could improve the accuracy of locating the kernel variables. And, an innovative fast locating algorithm based on the Windows XP kernel variables was proposed. At last, a fast memory data export algorithm based on MmPhysicalMemoryBlock was suggested with the example of kernel variable MmPhysicalMemoryBlock application. The experiments showed that, these two kernel variables locating algorithm are able to locate kernel variables preciesly, the fast memory data export algorithm is able to export wanted memory data with accuracy and integrity.
Jia Hongjin , Han Hongbin , Li Ting
2015, 38(5):33-36.
Abstract:To verification the reliability and the effectiveness of the RCS of large electric size target by using scaling model, derivation of the constraint conditions to get the same electromagnetic field of actual target by scaled model on the basis of the theory of electromagnetic field. Verified two standard objects which with same sharp and different scale by darkroom measurement and software simulation(FEKO,HFSS) respectively, and analyzed the RCS of a certain plane and scaling model by FEKO and HFSS simulation. It well solved the problem of large scale or super large complex target RCS difficult to obtain or cannot be.
Yan Li , Zhang Jinyi , Chen Xingxiu , Zhou Wenqiang , Liu Jiang
2015, 38(5):37-41.
Abstract:With the progress of the research of navigation system, navigation system has been widely applied in many areas such as highaltitude reconnaissance. Meanwhile, the application environment of navigation system may change, such as the change of indoor and outdoor environments. However, research at home and abroad are more inclined to single environment, and the algorithms are applicable only to a single environment. There are relatively fewer studies about panoramic environment algorithms. An four rotorcraft attitude estimation algorithm is presented. The algorithm can take different attitude calculation model according to the environment and the motion state of the four rotorcraft, and switch mode by the comparison between the variable and the threshold value. Experiments indicated that the algorithm can realize seamless switch when the environment of the four rotorcraft changes, has high accuracy, and has a good real time capability.
2015, 38(5):42-44.
Abstract:Considering that the instability of RSSI in indoor propagation makes the localization algorithm based on onetoone mapping between RSSI and location (distance) larger error, by the statistical analysis for RSSI, this paper proposes to build the interval mapping database between RSSI and distance in offlinesampling stage, and then to determine the specific location of the anchor point by the weighted Centroid localization algorithm in rough location area divided by anchor point RSSI in onlinemeasuring stage. The performance test results show that the position estimation error of each test point is slightly different and the average deviation is not high. It indicates that to some extent this method improves the position deviation problem due to the signal fluctuations such as multipath effects, NLOS propagation. Also, it proves the feasibility and effectiveness of this method.
2015, 38(5):45-49.
Abstract:In order to meet the storage speed of real time none compressed large area CCD camera, after analysis the character of digital signal and SCSI data transmission procedure, a method is presented which produce two image data by using FPGA, one of image data are written to SCSI disk array on DMA mode by SCSI controller, the other image data are send to memory by PCI interface and realtime display. The insufficient of traditional storage scheme is pointed, and the DMA technology solves this question. The access time of SCSI disk and the effect of storage speed by size of data block are analysis. Because of the nature image data don’t pass the PCI interface the storage speed improves very much, this method meets the requirement of large capacity image record and realtime display. Experiments results show that the system works under by a 2K×2K image with 25 f/s, the storage speed reaches 1 200 Mb/s, the system works stable and correct results make this method very ascendant in practical application.
Wu Guoliang , Wang Gang , Qi Lili , Wang Lei
2015, 38(5):50-52.
Abstract:With the increasing demand of the resolution, synthetic aperture optical system is more and more important in the field of space observations, the cophase of its sub exit has become the main factor that restricts its application, the traditional phase diversity method can detect wavefront error, but the complex structure of objective function, low precision and high computational complexity do not meet the practical needs. In this paper, we construct the phase diversity model by using the properties of Zernike polynomials, expand the phase by first order Taylor series and solve least squares problems to replace the nonlinear optimization problem. When the wavefront error is small this method can accurately recover the wavefront phase. Experiments show that the method can correct the phase error better than 1/60λ and achieve satisfactory image restoration results.
2015, 38(5):53-55.
Abstract:The paper presents a method on the surface defect detection of floor tile based on computer vision. With an improved image subtraction matching and correlation algorithm, the target image and the template image are partitioned into blocks and processed, and then the subarea of the target image is subtracted from the corresponding template image in the data base. Finally the correlation coefficient is used to determine whether the quality of the target image meets the requirements. Experimental results show that this method can accurately achieve the reliable and efficient surface defect detection of floor tile in realtime.This method can detect the 4.5 average defect and the average recognition rate can reach 95.74%,which is better than histogram statistical characteristics and GLCM.So the method is of great practical value of the surface defect detection of floor tile.
2015, 38(5):56-61.
Abstract:FPGA devices are more widely used in space remote sensing cameras. FPGA based on SRAM must be equipped with corresponding prom chips for storing FPGA programming data. The configuration is reloaded after power on.However, the configuration does not always succeed for it is easily affected by various factors. This paper describes FPGA configuration process, analyze the various factors affecting the configuration and make recommendations for design optimization. The Configuration circuits do not fail in hundreds of configuration tests after optimization..As space missions, FPGA configuration failure in remote sensing camera should never occur, in order to improve the reliability of poweron configuration, this paper presents a number of IO signal monitoring strategies. The use of high reliability antifuse FPGA which monitor the FPGA needed to be configured, can guarantee FPGA configuration almost 100% success. It has significant reference value in application of remote sensing cameras.
Lei Weiyan , Ao Zhenlang , Zhou Qinqiang
2015, 38(5):62-66.
Abstract:About the embedded terminal equipment upgrade difficult problem, this paper designs a remote upgrading scheme based on STM32. The scheme study the communication flow of Ymodem protocol, and IAP technology principle and IAP function realization based on STM32, including set the initial position and the interrupt vector table, APP program area flash erase, APP program written in flash, IAP jumps to APP procedures and so on. This paper using the RS232 standard serial port realizes the communication between PC and embedded terminal equipment based on Ymodem Protocol, namely embedded terminal equipment real time updates by remote mode. Experiments show that, the design has good application value and extension value.
Feng ShengminChen JuanhuaWang GuolinChen Sibing
2015, 38(5):67-71.
Abstract:With the development of large-scale integrated circuit and programmable technique, the degree of integration and programmable ability for timing equipment have been required higher and higher in the test range. As the restriction of space and transportation condition, it puts forward higher requirements for the volume and reliability of timing equipment especially for the vehicle equipment. Combining with the research project of test range timing equipment, a design project of IRIGB code generator is proposed based on FPGA by the CycloneⅣ FPGA chip EP4CE22 as the core and schematic diagram and Verilog language programming. The system has the characters of simple operation, high reliability, smaller volume and strong function expansion, which can widely be applied to measurement and control equipment of test range.
Cheng Zheng , Qiu Zhi , Hao Shiyong , Luo Bin
2015, 38(5):72-74.
Abstract:In order to design the PTD experimental platform of a aircraft,guided by the idea of standardization, modularity and generalization,The hardware of the measurement and control system of this experimental platform on the basis of PCI bus and devising the software of the system by the use of LabVIEW2010 version.Furthermore,The whole system is abe to collectdata, measure and calculate parameters and control switching values.The experimental test reveals that the measurement and control system has such good features as simple application,and stable and reliable operation,enhancing greatly the accuracy of platform test as well as the control efficiency.
Chen Peng , Ge Hongjuan , Yang Zonghan
2015, 38(5):75-77.
Abstract:In order to achieve the high voltage capacitor bank of the electroimpulse deicing system efficiently and safely charging, a series resonant topology pulse power supply based on DSP is researched in this paper. The average charging current of the capacitor bank is concluded by establishing the equivalent circuit of the different working mode, then the operating frequency and resonant parameters are designed, which ensure power supply work in under resonance state, in order to achieve a wide range of constant current charging and zero current soft switching state. Therefore, when the sensor detects the ice of the wing surface, the pulse power supply will work to deicing.
Guo Feng , Yu Jianfeng , Lu Zhenzhong
2015, 38(5):85-88.
Abstract:Aiming to the calibration requirements for degree of linearity, repeatability and slowmoving, the scheme of virtual instruments and USB data acquisition technology is put up. Through force sensors, signal conditioning device, data acquisition card, force loading device, upper computer, and system software, the system realize the automatic calibration. The calibration software can realize the succession data acquisition, data analyzing and result display. According to calibration standard JJG144-2007, the system we developed has high precision below 1%. The project can provide a new kind technology for the dynamic and continuing calibration for force sensors.
Chen Lu , Liu Weiling , Chang Xiaoming
2015, 38(5):89-92.
Abstract:In order to meet the industrial demand of the current waveform detection under the condition of noncontact, a noncontact type current waveform detection system based on hall sensor HW302 was put forward. The system used the hall sensor to collect current signal, and displayed towards the oscilloscope after the amplification of the signal processing circuit.Then the current waveform detection was achieved. To verify the correctness of the detection, different signal was applied to the inductance coil to detect the current waveform, and analyze the performance of the system. It was showed that the system detected the current waveform through the noncontact way, basically achieving the expected results.
Wang Shuguang , Wang Qingsheng , Liu Meili , Gong Wei , Gan Jiefu , Xu Liqian
2015, 38(5):93-96.
Abstract:Based on the analysis of security threats faced by the WSN, typical factors which affect the security of WSN are analyzed by building a simulation environment of WSN, then the security status of WSN is analyzed in different variations of network security threats and attacks. For each of the security evaluation index of WSN, this paper studies the corresponding security evaluation methods. By using WSN security evaluation methods, the WSN security evaluation experiements are carried out, that is the security evaluation index of WSN are carried out. Thus the risk of WSN is reduced from source, and the security of WSN is ensured.
Liu Lei , Sun Xiaofei , Zhang Yu
2015, 38(5):97-100.
Abstract:To solve the problem of safety related to property in the dormitory of undergraduates, an intelligent dormitory alarm system based on GSM module and infrared correlation sensor is proposed in this paper. The system uses STM32 as the main control chip, gathering and judging the signals of sensors placed on many doors of the containers. Once there is abnormality found, alarms are given by sounds and lights, meanwhile the system judges which container is, then sends text message to the owner. The owner can control the processor to defend or not. Experimental results show the accuracy rate of the antitheft alarm system reaches 91%.The function of the system is simple to achieve, the installation is convenient, and the effect that there’s only one host but many people can protect it is realized. The system is not only ensured that there’s no confliction between each other’s antitheft systems in the dorm, but also meet the antitheft demand of the whole dorm.
Gao Qingze , Chen Changjiu , Peng Fei
2015, 38(5):101-105.
Abstract:According to the need of underwater measurement equipment automatic recycling application, this paper introduces a design of electronic control buoyancy mechanism based on microprocessor. This mechanism takes the TI company's low power consumption microprocessor MSP430F149 as the core, the Intersema MS5541C pressure sensor as the sensing unit, the pneumatic solenoid valve as the controlled unit and takes the method of capacitor stored energy and release to drive the pneumatic solenoid valve and detects the maintain current to feedback regulate it . According to the demand of different condition of underwater measurement equipment to rise and descend, the buoyancy mechanism can control the pneumatic solenoid valve to close and release for adjusting the state of floating gasbag. This buoyancy mechanism has the advantages of high reliability and low power consumption.
Yu Yanlin , Zu Jiakui , Liao Zhilin
2015, 38(5):106-110.
Abstract:Inertial measurement method is widely used in attitude determination of lowcost civil MUH(Mini Unmanned Helicopter).But the dirft of gyroscope and the kinematic acceleration affect the accuracy of estimation.This paper designed a Kalman filter based on quaternion.According to the gyroscope and accelerometer signal,fusion the attitude of MUH.And designed adaptive covariance matrix of measurement noise to improve the fusion accuracy.Get stable and highaccuracy attitude information for stability augmentation system. Experiment data shows that the method can effectively solve the problem of attitude determination of MUH.
Li Zhongwei , Wang Peng , Cui Xuerong , Wu Chunlei
2015, 38(5):111-113.
Abstract:The limitation of bandwidth in the channel of drilling fluid, and the demanding for faster generation speed of the pressure wave signal about drilling fluid are two challenges to the transmission of data from the bottom of the well. Because of this, a novel pressure wave signal generator for drilling fluid with the employment of data compression is an effective way to overcome these difficulties. In this paper, the good quality of consecution of measured data, and the gentle trend of the values, provide the chance of conducting great compression to the date by using DPCM predictive coding methods. Experiments’ results approved that based on present hardware and facilities, the transmission speed will double distortion measure is also within a controllable range.
Liao Licheng , Mei Jinsong , Zhao Yang
2015, 38(5):114-118.
Abstract:The phenomenon of locomotive wheel tread irregularities seriously affects the safety of vehicle operation. This paper introduce the constitute and working principle of a locomotive wheel tread detection system.In order to improve the efficiency of irregularity’s recognition, this paper presents an algorithm based on wavelet analysis and modulus maxima in the MATLAB environment. This algorithm use wavelet to analyze the data and get the approximate and detail coefficients of data signal, than we use the modulus maxima method to analyze the singularity of data and orientate the position of data point where have an tread irregularity further. The results of experiment indicate that the effect of this locomotive wheel tread irregularities processing algorithm is obviously, and it can accurately judge the tread irregularities.
2015, 38(5):119-121.
Abstract:The FD-HM-ⅠHelmholtz coil, using high sensitivity of milli Tesla meter, magnetic induction intensity detection Helmholtz coil common axis point. Through the positive, reverse direction change current Helmholtz coil in the Yanan area, accurate measurement of the local magnetic field strength and magnetic inclination.
Zhang WendianSun XiaodongWang FengyunLong Mei
2015, 38(5):122-126.
Abstract:Based on the impedance sensor, we design a instrument for measuring water rate in crude oil. The least square method is employed first, Based on the measured data, the temperature coefficient of the impedance sensor is obtained , then the fitting curves of the relationship between moisture content and voltage at reference temperature is achieved. The impedance sensors now avaliable usually show the charge accumulation effect after working for a long time, which impacts the measuring precision of moisture content. In this paper, the discharge circuit is designed to discharge the stored charges regularly under the control of the microcontroller. Thus it provides an effective method to solve the problem of measurement error caused by charge accumulation. The experimental results show that this method can design the measurement of moisture content of crude oil with the high precision.
Liu Jie , Chen Dawei , Hu Haitao , Li Ke
2015, 38(5):127-130.
Abstract:This paper presents a method of license plate character recognition based on the combination of Zernike moment and wavelet transformation features. CPU, DSP and other large power integrated circuits in the dynamic burnin test, its shell temperature rapidly increased, unable to remain the temperature for required, lead to burn in test can not be in strict accordance with the requirements. For this reason, this paper designs the automatic temperature controller of high power IC dynamic, Including temperature acquisition, fan automatic control, and display circuit, so the device shell temperature can automatically control within a certain temperature range through the fan. And trying to validation the test method according to GJB 548B. The test results show that, the shell temperature control is accurate and effective(such as 85-90℃, the temperature interval can be set free, the display precision: 0.1℃), and the temperature display real timely.
2015, 38(5):131-134.
Abstract:A design of wireless signal strength measurement system in real time by using GNU Radio and USRP(Universal Software Radio Peripheral) is proposed in this paper . To quickly and accurately measure the signal strength, this paper use the band noise power, spectral filtering and moving average techniques in the frequency domain in the signal receiver. The system is lowcost, flexibility, scalability and portability, thus could reduce the system maintenance as well as upgrade costs. Finally, in the indoor wireless environment, measured the intensity of the filed compared the measured data with the raytracing simulation data the result proves the feasibility and effectiveness of the system in a real environment.
2015, 38(5):135-138.
Abstract:With the development of wireless communication, MIMO has become a hot research in the field of wireless communication. The prediction of the distribution of field and the channel capacity is the basic of communication system network planning and management which has important significance of the wireless network optimization. In this paper, we select the raytracing model and the mirror image method to establish indoor MIMO channel model and use the Matlab software to simulate the model. Firstly, we should establish the specific indoor scene and predict the path loss. By the comparison of the predicted and measured values, we can verify the correctness and validity of the model. Then, we analyse the MIMO capacity in theory. Lastly, we simulate and analyse the effect of SNR and the number of antennas on the MIMO channel capacity.
2015, 38(5):139-142.
Abstract:IP Network camera (referred IPCam), due to the advantages of flexibility with relevant technique and involving a wide range, has been widely used in the industry network video surveillance. But the lack of a unified interface standard , different manufacturers products in IPCam can’t do interconnection process, not only makes allowing interoperability between the various manufacturers become a serious problem, but also remains a major issue to build a largescale network monitoring environment. This paper focuses on the ONVIF protocol, first introduced the service composition and operation mode of the ONVIF protocol in detail, and analyzed the communication process from IPCam services to client. After mastering the basic principles of Web Services in the network video surveillance applications, studied the core content of ONVIF protocol. What’s more, Set discovery, device management, event processing and realtime streaming media service that ONVIF specified are designed and implemented in the IPCam platform finally. All products supporting ONVIF client can access the camera, make it access to the IPCam internal implemented services, which address the interrelated issues of network video products.
Editor in chief:Prof. Sun Shenghe
Inauguration:1980
ISSN:1002-7300
CN:11-2175/TN
Domestic postal code:2-369