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Table of Content

    25 December 2005, Volume 25 Issue 06 Previous Issue    Next Issue
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    Effects of Spacecraft Movable Accessory on the Attitude of Meteorological Satellite
    Liu Rui Wang Ping Lü Zhenduo(Beijing Institute of Control Engineering,Beijing 100080)
    2005, 25 (06):  1-7. 
    Abstract ( 1667 )   Save
    With the background of the next generation of geostationary orbit meteorological satellite,the effect of payload mirror motion and solar array stepping motion are studied.The(simulation) results show that the effects of payload mirror regular scanning motion and the solar(array) stepping motion on the satellite attitude are very small.But the satellite attitude is deeply(affected) by payload backbody calibration,so the compensation must be required,otherwise the pointing performance of payload mirrors can not meet the demands of satellite.
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    Research on Satellite Attitude Sensor Applying Remote Sensing Image Information
    Cai Xiaodong Ye Peijian(China Academy of Space Technology,Beijing 100094)
    2005, 25 (06):  8-13. 
    Abstract ( 1733 )   Save
    Landmark sensor acquires satellite attitude information from the remote sensing (images) by calculating the object movement between real-time images and template images and(thereon) computing the satellite attitude.The general scheme of landmark sensor is designed,in which image matching is the key technique.A coarse-to-fine image matching algorithm based on(image) regional features is proposed.The attainable precision of attitude acquisition is analyzed(theoretically),and the result shows that high-precision satellite attitude information can be(achieved) by the landmark sensor,which is of great value as a novel optical attitude sensor.
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    One Kind of Rigorous Design Method for Microwave and Millimeter-wave Filters
    Li Shengxian Fu Junmei(School of Electronic and Information Technology,Xi'an Jiao Tong University,Xi'an 710049)Wu Xuda(Xi'an Institute of Space Radio Technology,Xi'an 710000)
    2005, 25 (06):  14-18. 
    Abstract ( 2134 )   Save
    A kind of rigorous design method for microwave and millimeter-wave filters is (presented).The element values for distributed low-pass prototype filter are transformed into(general) K-inverters.Coupling junctions are computed by Mode-Matching Technique(MMT) or Coupled(Integral) Equations Technique(CIET) to achieved the exact S parameters and K-inverters(corresponding).All dimensions of coupling junctions and the length of resonators are obtained by(using) interpolation,and the filter is simulated by MMT program,HFSS or CST software,the(simulation) result agree well with the predicted values,and optimization is not needed during the(design) progress.A 26GHz rectangular waveguide band-pass filter is designed,both the simulation result by MMT,HFSS and CST and measured date keep good agreement with prototype values.This show that the design method is valid.
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    Study of the Strap-down Inertial Navigation System/Star Sensor Integrated Navigation System Algorithms
    Wang Peng Zhang Yingchun Qiang Wenyi Zhang Ronglin(Research Center of Satellite Technology,Harbin Institute of Technology,Harbin 150080)
    2005, 25 (06):  19-25+29. 
    Abstract ( 2058 )   Save
    The Strap-down inertial navigation system and Charge Coupled Device(CCD) can provide corresponding attitude′s data.Fusing these data,integrated navigation system′s error state value can be estimated and the aircraft′s position,velocity and attitude′s angle can be corrected base on Kalman Filtering.The algorithm of integrated strap-down inertial navigation system/star sensor integrated navigation system is educed in detail.The results of computer simulation show that the proposed system is feasible and the algorithm is effective.
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    A Method for Memory Fault Test in Real-time Systems
    Yang Mengfei~(1,2)Sun Zengqi~(1)Gong Jian~2(1 Tsinghua University,Beijing 100084)(2 Beijing Institute of Control Engineering,Beijing 100080)
    2005, 25 (06):  26-29. 
    Abstract ( 1584 )   Save
    A new memory test method according to fault models in real-time memory systems is presented.The main feature of this test method is that buffers are not used in the process of(testing),so that system resources are saved and test coverage rate is improved.The correctness of this memory test method is also proved.
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    The Analysis on Technology Development of Data Transmission in Remote Sensing Satellites
    Gao Weibin Ran Chengqi(Beijing Institute of Tracking and Telecommunication Technology,Beijing 100094)
    2005, 25 (06):  30-36. 
    Abstract ( 1736 )   Save
    Data transmission is one of key technology in remote sensing satellites.Based on the analysis of general demands of remote sensing satellites,this technology domain analysis and forecast are given,including data transmission rate,selection of transmission frequency band,data(compression),modulation and demodulation,data encrypting,coding and decoding and so on
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    Study on the Estimate and Accuracy of Burnout Time with Week Survey Data
    Xie Wenping Chen Jiye(Shaoyang University,Shaoyang 422000)
    2005, 25 (06):  37-42+64. 
    Abstract ( 1750 )   Save
    The position accuracy depends on three trajectory parameters at burnout,which are the accurate degree of time,speed and position.These can be calculated by analyzing aerocraft′s(impact) position without power after burnout.And the burnout time is the most important factor.The estimate of burnout time and its precision are studied with week survey data.At last the result of Monte-Carlo simulation is given.
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    Design of Semi-physical System for Micro-satellite Attitude Control
    Zhang Shijie Cao Xibin Wang Feng(Research Institute of Satellite Technology,Harbin Institute of Technology,Harbin 150080)
    2005, 25 (06):  43-50. 
    Abstract ( 2190 )   Save
    The design of Semi-physical system for attitude control subsystem of the flywheel controlled satellite is proposed with the dSPACE real-time simulator,single-axisair-bearing(platform),on-board computer,gyro and flywheel.Then the proposed system is used to the semi-physical simulation of large angle maneuver attitude control for small satellite only via flywheels.The results indicate that the control algorithm can satisfy the requirements of the AOCS(subsystem).
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    Design of Autonomous Homing Trajectory for Parafoil Delivery System
    Xiong Jing Qin Zizeng Cheng Wenke(Institute of Aerospace and Material Engineering,National University ofDefense Technology,Changshai 410073)
    2005, 25 (06):  51-59. 
    Abstract ( 1996 )   Save
    Firstly,based on six degree-of-freedom kinetic modeling and simulating,the basic flight characters of parafoil system and predigest the model are analyzed. Then,the idea of(multiphase) trajectory programming and features in each phase are introduced.And a set of homing project for different conditions is brought forward.The process of modeling for optimal control is also introduced.Normalization and equal scale,these two pretreatment methods improve precision of calculation,and facile choice of weighting factors.At last,a sample testifies the(feasibility) of the two methods and shows the characters for each.
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    A New Method for Parallel Radiative Transfer Coefficient Between Complex Surfaces
    Zhang Weiqing Xuan Yimin Han Yuge(School of Power Engineering,Nanjing University of Science and Technology,Nanjing 210094)
    2005, 25 (06):  60-64. 
    Abstract ( 1856 )   Save
    Aiming at parallel light,a new method for computing radiative transfer coefficient between complex surfaces is developed.And some disadvantages possessed by Monte-Carlo method are gotten over,such as more computational time and lower computational accuracy.The new method is analyzed and compared from respect to the computational time and accuracy,and results show that the new method is superior over Monte-Carlo method
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