Table of Content

    25 June 2005, Volume 25 Issue 03 Previous Issue    Next Issue
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    A Miniature Dual SINS/GPS/Doppler Integrated Navigation System
    Liu Ruihua (Civil Aviation University of China, Tianjin 300300)$$$$
    2005, 25 (03):  1-7+13. 
    Abstract ( 1945 )   Save
    A MEMS-IMUs based dual SINS/GPS/Doppler integrated navigation system is designed, and this will make the integrated system to have a systemic redundancy. The construction of the integrated system, the designing and calculation of the hierarchic alliance Kalman filter are discussed in this paper. Then the hard failure FDIR algorithm based on the filter measurements residuals and the soft failure FDIR algorithm based on the state esimations are given. The result of simulation shows that this system is better as flexible structure.
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    An Approach for Moonlet Precise Orbit Determination Based on Satellite Formation Flying
    Wang Jiongqi Wu Yi (National University of Defence Technology, Changsha 410073)
    2005, 25 (03):  8-13. 
    Abstract ( 1587 )   Save
    It uses Hill equation to depict the satellite movement of relativity and utilizes the ephemeris data received from satellite transponder to obtain the mutual distance. Through the simulation, which is compared with GPS autonomous orbit determination for the Moonlet, it indicates that this approach is effective and can realize moonlet precise orbit determination.
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    Research of Optimal Interpolation Algorithm for Digital Image
    You Yuhu Zhou Xiaokuan (Beijing University of Aeronautics and Astronautics, Beijing 100083)
    2005, 25 (03):  14-18. 
    Abstract ( 1694 )   Save
    The physical background of the popularly used image interpolation algorithms is analyzed first in this paper. Since the cubic convolution interpolation algorithm makes use of both direct and indirect neighbor pixels around the interpolated point, it is the best interpolation algorithm among the popular used inage interpolation algorithms. But the experiment results show that in the cubic convolution interpolation algorithm the given weights of direct and indirect neighbor pixels around the interpolated point are not the best ones. A recommended best combination of the weights is given then.
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    Research on Dynamic Behavior of Space Joint-dominated Structure Based on Nonlinear Normal Modes
    Wang Wei Yu Dengyun (China Academy of Space Technology, Beijing 100086) Ma Xingrui (China Aerospace Science and Technology Corporation, Beijing 100830)
    2005, 25 (03):  19-27. 
    Abstract ( 1801 )   Save
    Space joint-dominated structrues are widely used in many core components of modern spacecraft, such as solar arrays, antennas, etc. The dynamic behavior of space joint-dominated structure has a great impact on the stabilities and dynamic behaviors of spacecraft system. In order to indicate the dynamic behavior of the joint-dominated structure and then model the spacecraft system perfectly, it is importance to model the nonlinear subsystem and investigate its nonlinear dyamic behavior. This paper presents an approach to model the nonlinear subsystem and analyze it based on nonlinear normal modes. The advantages of this approach are to consider the joint- dominated structure as a multi-degrees system with local nonlinear constrains and then define the nonlingar normal modes as a movement on the invariant manifolds.
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    Bayesian Assessment Method for Performance Parameters of Liquid Propellant Rocket Engine
    Li Baosheng Lei Chungang (Beijing Aerospace Propulsion Institute, Beiijng 100076)
    2005, 25 (03):  28-34. 
    Abstract ( 1561 )   Save
    How to use data gotten is ground tests to estimate the performance parameters and the reliability in future flying is studied in this paper. The proper prior PDF and the post-prior PDF according to bayesian analysis are gained, and the bayesian point estimation and credible bounds of the parameters and the performance reliability are given.
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    Analysis of Passive Location Precision Using Ocean Surveillance Satellite
    Shen Rusong (National University of Defense Technology, Changsha 410073) Zhang Yulin (The Academy of Equipment Command and Technology, Beijing 101416)
    2005, 25 (03):  35-39. 
    Abstract ( 1717 )   Save
    The principle of using three satellites formation to reconnoiter and surveil targets on ocean passively is analyzed. The precision model of location making use of measuring the time difference of arriving is built. Based on the precision model, the relation between location precision and the satelliters′ formation configuration, orbit height, relative position with targets, orbit determination precision and measure error are deduced. The results of simulation show that increasing baseline length between the satellites rationally and maintaining uniformity of the satellites formation configuration and their relative position with target can improve the precision of locating target effectively.
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    Thermal Vacuum Test Method for Separate Module of a Satellite
    Pan Zengfu Li Guoqiang Hu Jingang (China Academy of Spacecraft Technology, Beijing 100086)
    2005, 25 (03):  40-45+65. 
    Abstract ( 2127 )   Save
    In this paper, test method of the Thermal Vacuum Test (TVT) for separate module of CBERS-02 is described. The difference between the separate module test and the whole satellite test are analyzed, and the key and nodus of the test are also referred. Test results show that the first separate module TVT is successful, and the expect purpose is achieved. At the end of this paper, the basic requirements to do a separate module TVT are discussed.
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    Image Compression Algorithm Based on the Quarter-tree for Satellite Remote Sensing Image Coding
    Zhang Hao (Beijing Institute of System Engineering, Beijing 100083) Cheng Zijing (Beijing Institute of Satellite Information Engineering, Beijing 100080) Zhou Xiaokuan (Beijing University of Aeronautics and Astronautics, Beijing 100083)
    2005, 25 (03):  46-53. 
    Abstract ( 1892 )   Save
    In order to resolve the contradiction between the need of high image quality and low data rates in data transmission and storage in the fields of satellite remote sensing, a new compression algorithm of combining spatial quarter-tree data architecture with multi-mode adaptive quantization technique is proposed. The algorithm is characterized with higher PSNR of the reconstructed image and lower computation complexity than JPEG, and the image detail preserving capability of the algorithm is better than that of JPEG. The ASIC realizing the algorithm is designed and manufactured using Field Programmable Gate Arrays. The peak processing speed of the ASIC can reach 288Mbit/s and its power consumption is lower than 1W.
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    Research on Nano-adhesive Used in Satellite Affecting Space Environmental Property
    Chen Ping Sheng Lei (Beijing Institute of Space Machine & Electricity, Beijing 100076)
    2005, 25 (03):  54-58. 
    Abstract ( 1720 )   Save
    The simulations of geostationary orbit condition experiments to adhesive used on satellite, and the same experiments to adhesive adding nano-SiO 2 are experimented in this paper. The results show that adding nano-material obviously influence reducing space venting, restrain demage of electron radiation and thermal cycling. The results offer the foundation of bonding structure and material life reliability on long-life satellite in our country, emerge the prospect of nano-material using in the space.
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    Fuzzy PID Vibration Control of Large Flexible Structures Based on IMSC
    Si Hongwei Li Dongxu (National University of Defense Technology, Changsha 410073)
    2005, 25 (03):  59-65. 
    Abstract ( 1764 )   Save
    Prportional-Integral-Derivative (PID) controllers are perhaps the most widely used controllers in modern industries because of its reliability, simplicity and validity. Fuzzy logical controllers are good at higher-order, time-delayed and nonlinear systems. Combining fuzzy logic controllers with PID controllers, a kind of controllers is designed in this paper, to resolve the vibration control of a complex system made of large flexible structure-space frame. The simulation result shows that fuzzy PID controllers are more effective in suitable structural vibration control by suppressing overflow especially for those systems with vague mathematical models.
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    Study on Pseudolite-augmented “Bei dou” Double-star Positioning System and Algorithm
    Wang Wei Liu Zongyu Xie Rongrong (Automation School of Northwestern Polytechnical University, Xi'an 710072)
    2005, 25 (03):  66-71. 
    Abstract ( 1825 )   Save
    Bei dou" double-star positioning system is a kind of regional positioning system. But because of the limitation of the number of satellites, double-star system cannot realize the real-time 3-D passive positioning. In this paper, a new idea of using pseudolites to augment the double-star system is put forward, and the algorithm and geometry of this augmented positioning sysem is studied. The simulation results indicate that the idea of double-star system augmentation with pseudolites is feasible and can fulfill the real-time passive positioning with the high precision independently, which offer a new way to develop the independent regional satellite positioning system at a relatively lower cost.
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