Research On The Critical Technology And Error Analysis Of Single Observer Passive Location

Single observer passive location and tracking (SOPLAT) system, avoid time synchronizetion between stations and complex data processing compared with multi-station location, therefore, it is subject to considerable attention. At present, methods of SOPLAT are not mature enough, and stability and precision of tracking algorithms need to be improved, and location error needs further research. In the dissertation, the technology of SOPLAT is researched, including location methods, filter algorithms and location error. The main content of this thesis is summarized as follows:1. Research on the method of SOPLAT joint phase difference change rate and Doppler frequency change rate was made. An improved location method was given, because the existing method can not calculate all the unknown parameters of the target through one measurement. The improved method constructs model through measuring phase difference and its change rate and Doppler frequency and its change rate, and it can calculate the location and speed of the target. In addition, it can get better accuracy because it adds more measuring information.2. An algorithm of SOPLAT was given based on SVD-EKF, and it can conquer the disadvantage that the algorithm may not be iteratively steady on numerical value by EKF. When the location algorithm is iterative, the covariance matrix of estimation error is singular value decomposed, so the iterative calculation of covariance matrix is converted to that of singular value decomposition, and the location accuracy and stability is improved.3. Research on the application of SOPLAT of partical filter (PF) and its improved algorithms was made. In respect that the base PF can not add the latest observation data to the proposal distribution, which may not get good location accuracy, an algorithm of SOPLAT based on mixed Kalman particle filter was given. Firstly, because the research on the PF which is applicated to passive location is mainly on bearing-only system, four new methods which are representational of SOPLAT were implemented systematically using PF, and the simulation showed their validity. Afterward, an algorithm of SOPLAT based on mixed Kalman particle filter was given. The algorithm can get better location accuracy even if the particles are less.4. Research on the errors of SOPLAT was made, in respect that the error analysis method is generally about single measurement, an error analysis method was given which can research the location errors furthermore under multi measurements. Firstly, in single measurement, when SOPLAT were implemented using the location methods of measuring Doppler frequency change rate, and joint phase difference change rate and Doppler frequency change rate, the location errors were analyzed. Then a summarization was made on the error characteristics of the four new location methods. Finally, an improved analysis method on errors of SOPLAT was given. Using this method, in single and multi measurements, we can systematically analyse the errors of SOPLAT qualitatively and quantificationally, so the method is catholically significative.