External Radiation Source Passive Location And Tracking Studies

Passive location and tracking based on opportunity transmitters has the advantages of excellent concealment and anti-interference, which has become one of the frontier projects in modern radar technology research. It has significant value for military in raising viability and effective counterattack ability to the regional defense system and practical use. The thesis focused the research of locating and tracking based on opportunity transmitters.The thesis studied the passive location and tracking based on opportunity transmitters, then discussed the method by using the LS (lease squares) method, TLS (total lease squares) method and SWLS (sequential weighted least squares) method. LS and TLS methods were used in a maneuvering target location in three-dimensional space, verifying the advantages of TLS method. A method based on highly auxiliary for low altitude target locating is presented. The location procedure was derived following four steps, i.e., locating from subsystem, eliminating the vague location, simplifying the fusion location of weighted least squares and Kalman filter. By comparing the simplified weighted least squares method and the proposed method, it showed that the proposed method has a higher location precision.The correlative factors influencing GDOP (geometrical dilution of precision) were investigated. It showed that GDOP dependents on not only the station position error and the standard deviation of measurement error from time difference location, but also the geometric position relationship between the target with each passive measurement station. Simulation analysis of GDOP was carried out by considering four aspects, which were altitude of target, distance between stations, master station position and altitude between stations respectively.The thesis studied the tracking of maneuvering targets based on the passive TDOA (time difference of arrival) location system and the MIEKF (modified iterated extended Kalman filter) based on Gauss-Newton iteration, and discussed the uniform linear motion model based on the IMM (interacting multiple-model) for maneuvering target tracking algorithm, uniformly accelerated motion model and turning model. An algorithm was presented by combining MIEKF with IMM, which can achieve the maneuvering target tracking. Through simulation experiments, the advantages and reliability of IMM-MIEKF were verified.In this thesis, the location and tracking algorithms were analyzed and deduced theoretically. The verification results through the simulation showed that the algorithm can achieve a desired result. The thesis provided new ideas and theoretical basis for further studies of passive location and tracking aided with opportunity transmitter.