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Yu T.,China National Aeronautical Radio Electronics Research Institute
Proceedings - 2010 International Conference on Communications and Intelligence Information Security, ICCIIS 2010 | Year: 2010

An analytic method solving Doppler changing rate is presented only by measuring Doppler shift or measured value of frequency. On condition that aerial vehicle is uniform motion, a Doppler direct ranging formula can be firstly derived by making use of the velocity vector identity, the relation between Doppler changing rate and tangential velocity as well as the specific value of Doppler changing rate at neighbor node. As soon as this ranging formula is substituted into the expression of Doppler changing rate, the analytic formula solving Doppler changing rate can be obtained. The analog calculation shows that the relative error derived formula is less than 0.01%. © 2010 IEEE. Source

Wang G.,China National Aeronautical Radio Electronics Research Institute
AIAA/IEEE Digital Avionics Systems Conference - Proceedings | Year: 2012

Integration technology of avionics system is a core technology of avionics for all new generation aircrafts. In accordance with the development of integration technology for avionics, this paper describes the composition and structure of avionics system integration technology, analyzes the mechanism and methods of the technology, discusses the abilities and objects of integration technology for avionics system. It also deeply discusses the idea, framework, content, constitution of structural integration, information fusion and mission synthesis of integration for avionics system. © 2012 IEEE. Source

Yu T.,China National Aeronautical Radio Electronics Research Institute
Frontiers of Electrical and Electronic Engineering in China | Year: 2010

A new direction finding (DF) method, in which the high-accuracy measuring can be realized only with single baseline, is presented used for airborne based on Doppler-phase measurement. The analysis discovers that the integer of wavelength in radial distance can be directly derived compositely, making use of the velocity vector equation and Doppler shift, as well as Doppler changing rate equation. From this, the integer difference of wavelength in path length difference of radial distance between two adjacent antenna elements can be obtained. As soon as the value less than a wavelength in path length difference is determined by phase difference measurement, the direction angle of target can be obtained. As compared with now existing interferometry first determining phase difference, this sort of direction finding method combining Doppler with phase difference first by determining path length difference does not have phase ambiguity nor require restricting base length. By simple mathematical identity transformation, we can prove that the equation derived in this paper is equivalent to an existing one from phase interferometry. The new method presented in this paper will certainly increase new developing force for the research and development of airborne single station direction finding system. © 2010 Higher Education Press and Springer-Verlag Berlin Heidelberg. Source

Yu T.,China National Aeronautical Radio Electronics Research Institute
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010 | Year: 2010

The method by single station speed measurement presented in reference [1] is further expanded. This calculation method can directly survey the uniform flight speed of target, only based on the actual measured frequency, by three stations linear array with very short baseline. Firstly, making use of Doppler changing rate, we can obtain both the specific value of advance angle and the specific value of frequency difference between adjacent measuring stations. Then, by combining it with the specific value of Doppler shift between adjacent measuring stations, the initial solution of advance angle can be solved. In order to exactly solve the advance angle, the relationship between tangential velocity and Doppler shift is found by decomposing Doppler shift in each detection nodes which is used for iterative computation. And then, the tangential velocity of Doppler changing rate is replaced by the one obtained from Doppler shift and iterative computing equation is constructed. The elementary analog calculation shows that analog error is not inversely proportional to basal line length and the iterative program can still produce true result when the basal line length is by far less than a wavelength. © 2010 IEEE. Source

An J.-X.,Tsinghua University | Wang G.-Q.,China National Aeronautical Radio Electronics Research Institute | Li S.-F.,Tsinghua University | Zhu J.-H.,Tsinghua University
Ruan Jian Xue Bao/Journal of Software | Year: 2010

As the size and complexity of mission-critical application software continues to grow, the cost of Software Testing (ST) is also increasing. The numerous methods and processes used to evaluate ST dynamically and quantitatively to improve testing efficiency serve as practice problems in the ST field. Based on multi-dimensional test coverage models, this paper proposes a dynamic evaluation method for ST and discusses it from the viewpoint of testing monitoring information, dynamic analysis and evaluation models, and testing optimized strategy. Furthermore, a concept, Synthetic Test Coverage (STC), is defined in this paper, and its empirical formulas are also presented. Examples show that the methods are useful in helping ST evaluation groups to track and control the effects of ST and for improving the user's ability to observe and control the ST process. © by Institute of Software, the Chinese Academy of Sciences. All rights reserved. Source

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