• Volume 39,Issue 1,2016 Table of Contents
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    • >Research&Design
    • Design of a novel square-shaped antenna with dual-band and pattern reconfigurable characteristics

      2016, 39(1):1-4.

      Abstract (1334) HTML (0) PDF 2.66 M (1883) Comment (0) Favorites

      Abstract:A novel rectangleshaped antenna with dualband and pattern reconfigurable characteristics is presented in this paper. The antenna consists of a patchslotsquare loop structure and surrounding four QuasiHorn parasitic patches with Ushaped slot. By reconfiguring the depth of the side slot in the Ushaped slot, the antenna can cover two resonant frequencies of 5.25 GHz and 2.45 GHz, respectively. The main lobe of each pattern directs to one of four different directions in the plane with the elevation angle of 45° or 90° by controlling the states of one set of connections among the center patch, square loop and QuasiHorn parasitic elements. The antenna, which operates at two resonant frequencies within 2.42~2.52 GHz and 5.21~5.32 GHz, has a good performance of directional radiation properties, so that it has potential applications in wireless communication systems with multiple operating frequency bands and high performance against the interference.

    • Design of broadband amplifier with GaN power device in L band

      2016, 39(1):5-8.

      Abstract (1058) HTML (0) PDF 1.52 M (1935) Comment (0) Favorites

      Abstract:In order to solve the problem of narrow working band and low output power and poweradded efficiency in current wireless communication system, this paper proposes a new type of the broadband high power amplifier in L Band designed by GaN device made by CREE. A method based on sourcepull/loadpull simulation has been used to find optimum source and load impedances .Then using an approach of mixing of microstrip line and capacitor,wideband matching networks is designed. Largesignal measurement results show that when the input power is 34 dBm among the band of 300 MHz in the Lband (relative operating bandwidth is 27.7%), the output power is higher than 50.4 dBm (108 W) , the poweradded efficiency (PAE) is over 48% and the plainness is ±0.1 dB at the whole working band. The data indicates that the power amplifier based on GaN has the advantages of wide band, high efficiency and output power.

    • Link constrains in RFID with intensive tags

      2016, 39(1):9-13.

      Abstract (1232) HTML (0) PDF 2.90 M (1342) Comment (0) Favorites

      Abstract:When laying intensive tags, there is a coupling between the UHF RFID tags. It causes the system performance degradation. If the power one tag received from reader is less than the activation power of coupling tags, or the reader can’t receive the reflected signal of coupling tags, then the reader can’t be normal communication with the coupling tags. Firstly, in this paper, the performance of the forward link and the reverse link theoretically derived from the coupling tags. And this paper also simulated the gain and scattering area when many tags are put together. Then the ratio of the maximum reading distance of forward and reverse link analysis and figures out RFID restricted link. Finally, the experiment of antenna probe proves this thesis conclusion. The conclusion for the reader antenna selection, proper placement position of tags and improve RFID tag read performance system is of great significance.

    • Antijamming measures of mediumfrequency power supply application system

      2016, 39(1):14-18.

      Abstract (1025) HTML (0) PDF 1.66 M (1571) Comment (0) Favorites

      Abstract:Since the surrounding of mediumfrequency power supply exist a large number of harmonics and the electromagnetic interference, it unable to work normally. Firstly,This paper introduces the application and problems of the medium frequency power supply. In order to improve the antiinterference ability of the microprocessor in the mediumfrequency power supply application system, the article designed antiinterference measures from four aspects of inhibition of interference sources, interference sources of segregation, interference reduction and the improvement of its antiinterference ability. Last,using MATLAB simulation software to establish the simulation model of the 12phase rectifier to verify whether the design of the filter has the rationality through simulation analysis was made on whether to place the RLC series filter in the side of power supply. The simulation results show that placing the RLC series filter in the side of power supplyt can effectively restrain harmonics.

    • Design and control of Omnidirectional mobile platform based on STM32

      2016, 39(1):19-21.

      Abstract (1114) HTML (0) PDF 1.10 M (1481) Comment (0) Favorites

      Abstract:In order to achieve the Omnidirectional mobile and obstacle avoidance of the platform,a mobile platform control system is designed.Using infrared sensor and the differential drive of brushless motor to achieve pathtracking,using ultrasonic sensor to achieve distance measure.According to the processing and analysis of the data which collected by the platform to achieve obstacle avoidance.The system also has a wireless control mode , which allowed operator to realize the direction control of the mobile platform by operate a joystick when the mobile platform meets the obstacle or driving in nontracking orbit. Experimental results show that the mobile platform can detect and correct aspect automatically and achieve collision free trave.

    • Research on power transformer relay protection based on wavelet transform

      2016, 39(1):22-26.

      Abstract (1251) HTML (0) PDF 3.43 M (1301) Comment (0) Favorites

      Abstract:In this paper a new method based on multiresolution analysis of wavelet transform is presented to distinguish the inrush current and internal faults with the ratio of energy change rate as the criterion. This algorithm is called the wavelet energy method. This research uses SIMULINK to build simulation models of inrush current and shortcircuit current to get waveforms of them. The high frequency coefficients of the two are extracted by wavelet toolbox, and the energy of each scale is obtained. Simulation results show that the method is simple,convenient and it is capable to distinguish inrush current and shortcircuit currents effectively.

    • Design and implementation of space target ISAR imaging display and control terminal

      2016, 39(1):27-30.

      Abstract (1387) HTML (0) PDF 795.07 K (1343) Comment (0) Favorites

      Abstract:The display and control terminal is an important part of a radar system.It provides radar system control operations and displays the target information for users. This paper introduces a display and control terminal for space target ISAR imaging based on VS2010. In order to receive the broadband echo signals in real time, this display and control terminal samples and receives radar target echo signals by using dedicated hardware. Besides,it uses CPU and GPU heterogeneous parallel processing to complete echo data ISAR imaging process and the displaying of imaging process result. Ultimately,this terminal achieves the setting of system parameters,the storage of the high speed realtime echo data,the realtime ISAR imaging process and the display and output of onedimension distance image and twodimension distanceorientation image on a common PC.

    • Analysis and evaluation of uncertainty of rise time measurement of digital oscilloscopes

      2016, 39(1):31-34.

      Abstract (1129) HTML (0) PDF 932.41 K (1438) Comment (0) Favorites

      Abstract:In order to realize the evaluation of rise time measurement of digital oscilloscopes, according to the method of Verification regulation for digital oscilloscope, the rise time of oscilloscopes is measured. In this paper, the uncertainty sources of measurement result is analyzed. Using Tektronix’s TDS3032C digital oscilloscopes as an example, the paper introduces the measurement result uncertainty evaluation process of the rise time of digital oscilloscopes, and given the evaluation results. Practice proves that the method is logical and effective, which can be referenced for writing oscilloscope verification device standard report and evaluation of rise time of oscilloscopes.

    • Multiresolution rendering of complex triangular mesh model based on GPU

      2016, 39(1):35-39.

      Abstract (1030) HTML (0) PDF 2.56 M (1279) Comment (0) Favorites

      Abstract:In this paper, an approach is proposed for multiresolution rendering of triangular mesh model with zero genus which based on GPU. The triangular mesh parameterized onto a spherical domain, then the geometry images is constructed with the parametric results. The quadtree is constructed on the geometry image, finally the LOD selection and mesh simplification is performed in the shader. The time of the simplified model process is reduced with use of GPU highly parallel computing features compared with the existing methods. The experimental results show that this approach ensure the quality of rendering and meet the requirements of realtime rendering.

    • Simulation and analysis of differential via based on SIwave and Designer

      2016, 39(1):40-44.

      Abstract (1609) HTML (0) PDF 5.11 M (1688) Comment (0) Favorites

      Abstract:With the increasement of signal frequency and PCB wiring density, the effect of PCB via structure on signal integrity is more and more obvious. The rationality of via design can greatly affect the transmission quality of PCB signal. Based on SIwave and Designer simulation software, the PCB structure model for differential via analysis is established. According to different via radius, pad size, antipad size, via length and whether it has a stub, nonfunctional pads, the S parameters in the frequency domain are extracted respectively and the TDR waveforms of the corresponding time domain are obtained. The influence of via structural parameters on the transmitted signal is analyzed in a comprehensive way, and suggestions on the PCB via design are proposed. Through the analysis of via on the differential line of actual PCB, the rationality of the proposed via design is verified.

    • Research of tracking a ballistic object in reentry phase

      2016, 39(1):45-48.

      Abstract (1109) HTML (0) PDF 1.33 M (1375) Comment (0) Favorites

      Abstract:The problem of tracking a ballistic object in reentry phase is studied from radar observations. A model with highly nonlinear state and measurement equations is considered, according to which three suboptimal filters are designed, namely Kalman filter, Unscented Kalman filter and Particle filter. Simulation results indicate that these filters do well in good accuracy and tolerable computational complexity respectively.

    • The design of microwave receiver for missile radome measurement system

      2016, 39(1):49-53.

      Abstract (1056) HTML (0) PDF 1.79 M (1931) Comment (0) Favorites

      Abstract:Missile radome is the key part of precision guided radar missile, and its main parameters directly affect missile operational performance. High precision, high efficiency and automatic performance measurement is very important for radome development and production. This paper introduce a scheme of microwave receiver with digital microwave phase shifter for radome performance measurement, which have characteristic of high accuracy automatic phase shift, thus providing accurately and quickly measurement of missile radome Boresight Error(BSE).

    • Design and simulate on cylindrical conformal microstrip patch antenna with PBG structure

      2016, 39(1):54-56.

      Abstract (1060) HTML (0) PDF 1.36 M (1396) Comment (0) Favorites

      Abstract:This paper proposes a new structure named Photonic Band Gap(PBG) for microstrip patch antenna. The new PBG structure is etched on the dielectric plane of a probefed microstrip patch antenna and arranged by a certain rule. The cylindrical conformal microstrip patch antenna with PBG structure was simulated by HFSS. The simulation results indicate that using the PBG structure which is arranged by a certain rule on the antenna could suppresse the propagation of the surface wave, significantly improve the cylindrical microstrip patch antenna bandwidth and gain, effectively improve the cylindrical microstrip patch antenna radiation pattern.

    • Analysis on the layout of smallscale antenna uplink arraying for deep space

      2016, 39(1):57-60.

      Abstract (1162) HTML (0) PDF 1.92 M (1479) Comment (0) Favorites

      Abstract:The requirements of the array layout is given to solve the problem of the effect of antenna layout to the farfield power combining gain in antenna uplink arraying,including the minimum distance between elements,the compactness,flexibility,scalability and economical of layout. The layout of smallscale array(3~36 array elements) is analyzed, and of the highest power gain of different array element is designed.Then,using computer simulate lunardistance farfield power gain of different layouts,the gain value is compared and summed up some rules.The simulation results show that the optimal layout is consistent with theoretical analysis. considering the scalability of arraying scale, reference layout of 16 and 36 array elements is given.

    • Design process and method research of BIT for Launch vehicle electrical system

      2016, 39(1):61-64.

      Abstract (1056) HTML (0) PDF 824.11 K (1380) Comment (0) Favorites

      Abstract:For launch vehicle, great testability design can effectively shorten launch flow and increase launch success rate. BIT(buildin test) is an important technique to improve the testability, maintainability and fault diagnosis of capability performance of a system or equipment. In this paper, analysis of the feasibility of BIT for launch vehicle electrical system and the design process and method of BIT is proposed, based on the background of new generation launch vehicle XX5. The purpose of this paper is to establish a standard set of BIT design process for launch vehicle electrical system, as the basis for Optimizing testing process and shortening the test cycle.

    • >Theory and Algorithms
    • Method for estimating the optimal subarray number of phased MIMO radar

      2016, 39(1):65-68.

      Abstract (1119) HTML (0) PDF 1.18 M (1387) Comment (0) Favorites

      Abstract:The transmit array of phased MIMO radar is partitioned into a number of fullyoverlapped subarrays. Considering the performance of sidelobe, to determine the optimal subarray number, beforming of phased MIMO radar is studied. The beampattern is expressed as the product of transmit beampattern, waveform diversity beampattern and receive beampattern. Through designing the position of sidelobe and zero point, this paper proposes a method to estimate the optimal subarray number. If the relationship of subarray number, transmit and receive array elements in this paper is satisfied, the best performance of sidelobe can be achieved.

    • Solution of compensating dynamic lag basedon positive velocity feedback for ship radar

      2016, 39(1):69-71.

      Abstract (1038) HTML (0) PDF 706.34 K (1317) Comment (0) Favorites

      Abstract:Compound control is a common method to reduce the tracking lag error for ship radar. However, the use is limited.The speed information of tracking target needs to provide. A new method of dynamic lag compensation based on positive velocity feedback for ship radar is proposed. In the absence of speed signals, the positive velocity feedback tracking link with lowpass filter is paralleled in the speed loop. The high frequency error component is filtered by the lowpass filter. The low frequency segment of the logarithmic amplitude frequency is improved obviously. Through the experiment, the new method based on positive velocity feedback reduces the speed error and acceleration error, and the radar tracking accuracy under marine dynamic environment is improved significantly.

    • Oil charging intelligent management system for service car based on vehicle network

      2016, 39(1):72-75.

      Abstract (1026) HTML (0) PDF 1.18 M (1331) Comment (0) Favorites

      Abstract:In order to solve the unreasonable and too costly of fuel use at the status of cash settlement, designed an oil charging intelligent management system for service car based on vehicle network technology relying on electronic label identify technology, radiofrequency technology, GPRS technology, database technology and publishing technology of dynamic web page. The working process of the system is explained and the design of software and hardware are also realized. Under the premise of not changing the existing filling device and equipment of the gas station,experiments show that the system has stable operation, high reliability, low cost at design and operating .The system improved the informationization and intelligent management at oil charging and financial settlement for service car, has high application value.

    • Study on the coherent integration for wideband radar based on frequency domain correction algorithm

      2016, 39(1):76-79.

      Abstract (1354) HTML (0) PDF 2.33 M (1267) Comment (0) Favorites

      Abstract:Coherent integration is used to improve the signaltonoise ratio when radar detects the target, the radial motion of moving targets will lead to range migration, which will degrade the performance of coherent integration. The simulation shows that range migration is obvious when detecting the fastmoving target with wideband radar, so it is important to correct range migration. A new algorithm called frequency domain correction was proposed, the digital pulse compression and the compensation of the moving terms are completed in the frequency domain. The simulation shows that the Keystone transform and frequency domain correction algorithm can compensate scatter migration through resolution cells without knowing the velocity of targets. Therefore, detection performance of wideband radar is improved because of the achievement of coherent integration in multicycle echoes. The algorithms' operation amount were analyzed and the result showed that the new algorithm’s operation amount is far less than the Keystone transform, and the method is easy for engineering implementation.

    • Measurement uncertainty assessment method of spaceborne equipment’s power line conducted emission

      2016, 39(1):80-83.

      Abstract (1089) HTML (0) PDF 627.34 K (1354) Comment (0) Favorites

      Abstract:Measurement uncertainty assessment of spaceborne equipment’s power line conducted emission is very complex. Based on analysis uncertainty sources of the power line conducted emission measurements from 10 kHz to 10 MHz(CE102), taking a spaceborne equipment as test equipment, measurement uncertainty methods of CE102 is studied. Firstly, the measurement principle of CE102 is introduced. On the basis of analyzed the measurement principle, the main uncertainty source including the measurement repeatability, instrument’s measurement performance and impedance mismatch,et al, is determined. Secondly, mathematical model of measurement uncertainty is established, and standard measurement uncertainty of each component is assessed. Finally, the expanded uncertainty of CE102’s measurement results is calculated by GUM method. The results show that the expanded uncertainty of a spaceborne equipment’s CE102 measurement results is 2.7 dB. The results give a positive effect for the EMC measurement systems development in laboratory building, improve the laboratory measurement capability and protect the quality of the measurement results, and it has important reference value for the CE102’s measurement uncertainty assessment of electronic equipment on other military platform.

    • QoSQoE mapping model based on back propagation neural network

      2016, 39(1):84-87.

      Abstract (1472) HTML (0) PDF 1.34 M (1497) Comment (0) Favorites

      Abstract:With the development of the Internet. People care more about the QoE (Quality of Experience)score of these services instead of the network parameter . While the QoE assessment of IPTV service based on image analysis like PNSR and VQM need full reference video to calculate the MSE with poor real time performance and also complicated .This paper had a research on the QoS to QoE mapping model based on the BPANNs,including the training and predict the QoE assessment using QoS parameter ,then verification this model. Turn out that this QoSQoE mapping model is well performed with high accuracy and fitting index.

    • >Embedded Technology
    • Design of PMSM control system based on DSP

      2016, 39(1):88-92.

      Abstract (1592) HTML (0) PDF 2.35 M (1246) Comment (0) Favorites

      Abstract:Alldigital permanent magnet synchronous motor (PMSM) control system based on digital signal processor (DSP) was designed to improve the control precision and instantaneity of PMSM servo system. The DSP (TMS320F28335 ) has rich onchip resource and floatingpoint calculations unit, which makes hardware design simple and operation fast. On the basis of mathematical models and vector control theory of PMSM, the hardware and software for PMSM control system was designed. The control system has functions such as completion of control algorithms、current and rotor position acquisition、speed calculation and SVPWM generation. The experiment on 1.5 kW PMSM of Syntron corporation was conducted and the results show that the control system has accurate speed, good control performance and stable operation.

    • The design of board worked in Initiator mode of PCI bus based on PCI9054

      2016, 39(1):93-98.

      Abstract (1051) HTML (0) PDF 3.46 M (1705) Comment (0) Favorites

      Abstract:PCI bus is widely used in modern electronic test and measurement fields. However, current testing facilities based on the PCI bus are mainly Target devices of PCI bus, which greatly limits the performance of testing facilities. This paper, firstly, presents the working principle in Initiator mode of PCI bus and then realizes the function of testing facilities worked in Initiator mode of PCI bus by the combination of PLX PCI9054 chip and FPGA. The design can effectively improve the realtime performance among testing facilities on data interaction, and can be used as connection between testing facilities and dedicated storage device. At last, the paper presents examples between devices which are worked in Initiator mode of PCI bus and fully verify the feasibility of the design.

    • Implement of Test Acquisition Information Transmission Based on RFID

      2016, 39(1):99-104.

      Abstract (1259) HTML (0) PDF 3.61 M (1284) Comment (0) Favorites

      Abstract:Because of the frequency range,security and accessibility,RFID may take the place of wireless transmission network such as Wifi、infrared and bluetooth which are not suitable for military and wired network which is inconvenient for test operation,and it carries out the data transmission:Take digital oscilloscope for example as test equipment,introduce the general planning、software and hardware structure of data transmision and the work mode of each module of RFID.Test data transmission needs critical software structure such as internal communication protocol and information frame,and use test drivers and interface software as base support.The entire system sends the data wireless from RFID module of test equipments to RFID module of PMA ,and show the test result through main panel of virtual instrument on PMA.Finally finish the wireless transmission from test equipment to PMA.

    • Design of 0.5T magnetic resonance imaging console based on SOPC

      2016, 39(1):105-109.

      Abstract (1047) HTML (0) PDF 2.50 M (1297) Comment (0) Favorites

      Abstract:Aiming at the development of the digitalization and miniaturization of the MRI system console, the basic structure and work flow of console for the 0.5T MRI were introduced. The consde is designed based on highly integrated SOPC system of FPGA, network communication, data processing, waveform generating is realized and peripherals in signal FPGA is controlled. Realization of tuning the wave, modulation & demodulation, gradient eddy current compensation, decimation and multiple filtering by PC. Finally the system are tested, results show that the system has the merits of high reliability, flexible pulse sequences, providing a compact and flexible scheme for MRI console.

    • >Application of Programmable Device
    • Research and implementation of the synchronization mechanism of ARINC659 BUS based on FPGA

      2016, 39(1):110-113.

      Abstract (928) HTML (0) PDF 1.92 M (1311) Comment (0) Favorites

      Abstract:ARINC659 bus is a standard bus of data transfer between LRMs in Avionics which can be Integerated and modulared.The strong point of ARINC659 bus are the multiple redundant structure and the TDPA method used in Frame transceiver. One difficulty of ARINC659 bus is implementing its synchronization mechanism. This paper introduced the basic content of ARINC659 bus espscially the synchronization mechanism of ARINC659 bus . Using A3P FPGA and verilog to describe the synchronization mechanism of ARINC659 bus under Libero platform and sample the singal by online debugging tool called identify. The final test results show that the system is normal and stable which is accord with the requirements of the protocol.

    • >Intelligent Instrument and Applications
    • Research and implementation of smart home system based on threelayer structure

      2016, 39(1):114-118.

      Abstract (1111) HTML (0) PDF 2.06 M (1105) Comment (0) Favorites

      Abstract:To improve the reliability and convenience of smart home control function, on the basis of IOT structure, a threelayer smart home system, combined by sensorcontrol layer, networkcommunication layer and service layer, is designed. ZigBee technology, WiFi technology, network communication technology and GPRS is used in the system. By using a phone based on Android platform, we can control the smart home system in shortrange or remoterange. By using different wireless transmission schemes to solve power consumption and reliability issues of the system. The actual test result shows that the smart home system has characteristics of easy to operate, high reliability and low cost, and can be promoted.

    • >Sensor and Non-electricity Measurement
    • Numerical simulation on Vortex generating body position of vortex flowmeter

      2016, 39(1):119-122.

      Abstract (911) HTML (0) PDF 2.15 M (1064) Comment (0) Favorites

      Abstract:The research of flow field on Vortex generating body position of vortex flowmeter is focused on twodimensional at present,but the actual flow field is threedimensional model.In view of the fact that the twodimensional simulation can not fully verify the flow field generated by the actual fluid impinging the Vortex generating body. The 3D simulation model was built according to the actual mechanical dimensions of vortex generating body using the numerical simulation software platform Ansys Workbench FLUENT in this dissertation.Then make the mesh subdivision on the simulation model ,and calculate it by NS equation.The comparison between the simulation and the real experiment shows that the actual vortex flow field can be simulated by the FLUENT software .Finally with the help of FLUENT software, the influence of generating body position can be determined by adjusting the the translation of generating body in the condition of different Current Speed but the same probe position,So that the maximum allowed translation position δ of generating body can be accessed.

    • >Data Acquisition
    • Study on new method of online monitoring of PD signal noise insulation cable for mine

      2016, 39(1):123-127.

      Abstract (865) HTML (0) PDF 2.89 M (1083) Comment (0) Favorites

      Abstract:The extracted partial discharge (PD) signal is easy to be covered by all kinds of noise and interference in the insulation condition of mine high voltage cable online monitoring system and have a great impact on the accuracy of the monitoring system .This paper puts forward an algorithm, based on feature vector (EVA), which integrates improved automatic blind equalization (BE) and automatic morphological threshold (AMT) methods for noise reduction. Choosing a balance signal to reveal the PD pulse by automatic blind equalization method firstly, and then using AMT to determine the threshold according to the balanced signal,so as to achieve the purpose of noise reduction. Through the laboratory and field practical tests, the results show that the proposed method is efficient and saves signal integrity as far as possible for extracting PD signals in severe noise pollution signals.

    • >Online Testing and Fault Diagnosis
    • Fast drawing algorithm of power supply system diagram based on automatic capture of directly connected devices

      2016, 39(1):128-133.

      Abstract (873) HTML (0) PDF 2.07 M (1006) Comment (0) Favorites

      Abstract:In coal mine highvoltage power supply system diagram, there exist more cases using direct connection instead of cable between electrical equipments. And the existing drawing method, aiming at the direct electrical equipment, uses the way of artificial alignment which leads to tedious and slow drawing process, even reduces the accuracy. To solve the above problems, based on the characteristics of the coal mine highvoltage power supply diagram, a quick drawing method is proposed which can realize automatic capture of connections between electrical equipments, can effectively improve the speed of alignment between the two direct electrical equipments. What’s more, the alignment accuracy is much higher than manual alignment, which can reach100%. And the drawing speed can be increased more than 3 times, which reduces the complexity and cost of drawing the high voltage power supply system diagram complexity and cost, has the characteristics of high accuracy, fast speed, simple operation, and so on. It can realize fast drawing of diagram effectively.

    • High precision power quality monitoring system

      2016, 39(1):134-141.

      Abstract (833) HTML (0) PDF 3.27 M (1236) Comment (0) Favorites

      Abstract:The project has studied and designed a monitoring and management system for power quality. The designed system adopts the new architecture based on DSP+PC. Through researching the newly national power quality standard and analytic method for power quality, the relevant power quality algorithms containing FFT, wavelet transformation and IEC are simulated by the tool of MATLAB. The hardware platform takes the DSP of TMS320F2812 as core, besides, the technology of hardware PLL greatly reduces the spectrum leakage and fence effect.The monitoring terminal program is completed with development environment CCS3.3. The monitoring center interface is developed with Visual Basic, and receives communication data from the terminal unit through RS232 based on Modbus communication protocol.After debugging and experiment, the designed system is stable and reliable . The system runs well and the project has reached the expected design aims.

    • Fault simulation of train based on updated finite element model of car body

      2016, 39(1):142-146.

      Abstract (717) HTML (0) PDF 3.23 M (936) Comment (0) Favorites

      Abstract:The building, updating and application of the finite element model of high speed train car body are investigated. The complicated three dimension model of car body was represented by a simplified two dimension model, and reasonable coupled constraint conditions were imposed. First, the natural frequency and vibration modes of the car body were obtained by finite element modal analysis. Then the model was updated by using experiment results, parameters such as elastic modulus and density were modified. Finally, dynamic response of car body was calculated from the updated finite element model. The results indicates:1) The error of modified first four modes has been significantly reduced, the simulation coincides well with experiment data:2)The example of bolt failure simulation shows that the updated finite element model of car body can guide the placement strategy of testing point, analysis of testing results and fault judgment.

    • >Photoelectric Detection
    • Research on the influence mechanism of earth's magnetic field on zero bias of high precision FOG

      2016, 39(1):147-150.

      Abstract (791) HTML (0) PDF 997.86 K (1203) Comment (0) Favorites

      Abstract:Combined with "four position" error problem in inertial navigation system calibration, it was analyzed that the influence mechanism of magnet sensitivity on zero bias stability of FOG in theory, we can obtain the cosine function model between gyro bias and the angle that magnetic field effect on the optical fiber ring; the Influence of magnet field on bias stability is linear, the influence of magnet field with arbitrary directions can be resolved into the sum of two orthotropic magnet fields. Finally, we tested two F120 high precision fiber optic gyroscopes at room temperature and static state, and got zero bias of gyro is 0.2o/ h, 0.3o/ h in all direction range, and zero bias of gyro was decreased to 0.027o/h, 0.038o/h with magnetic shielding, the magnetic shielding can decrease the influence on zero bias of high precision FOG from earth’s magnetic field effectively.

    • >Network Testing Technology
    • Implementation and analysis of backup router based on SpaceWire TimeCode

      2016, 39(1):151-156.

      Abstract (1016) HTML (0) PDF 3.80 M (1125) Comment (0) Favorites

      Abstract:SpaceWire is a new bussing technique provided by European Space Agency. As the new bussing technique, SpaceWire enhances the functions of error detection and error recover[1]. In order to solve the problem of blocking in the net and reduce the SpaceWire delay[2],SpaceWireD performs the timecode flowing in the net and schedule table. Aerospace has high requirements for the reliability of devices. Router is the indispensable component in the net,the reliability of the router affects the reliability of the net[3]. This text based on accomplishment of the SpaceWire router by modifying Dundee router IP Core applies the structure that one board with two routers, it uses the corporation between one of the reserved bits of timecode in SpaceWire and modeshift of the SpaceWire router to realize the hot backup function and enhance the reliability of the SpaceWire router. Finally, by using testbench to prove the function of modeshift,it can work properly, analysis and comparison prove that this scheme can enhance the reliability of the router.

    • Research on MIMO channel characteristics in corridor environment at 2.6 GHz

      2016, 39(1):157-160.

      Abstract (874) HTML (0) PDF 1.27 M (1052) Comment (0) Favorites

      Abstract:In this paper, we obtain the MIMO channel characteristics of the corridor environment with a high density 829 MIMO channels at 2.6 GHz with 20 MHz bandwidth. The RUSK channel sounder is applied in the channel measurement campaign, which can obtain the highresolution measurement results. The channel measurement campaign has been performed in classical office corridor and semiopen corridor scenarios. We focus on the characteristics of delay spread and correlation with different antenna polarization. For different scenarios, the crosspolarization power ratio (XPR) and angle spread are also analyzed.

Editor in chief:Prof. Sun Shenghe

Inauguration:1980

ISSN:1002-7300

CN:11-2175/TN

Domestic postal code:2-369

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