Based On External Illuminators Target Echo Parameter Estimation Algorithm

The passive radar based on opportunity transmitters has potential superiority and prospect in the future electronic war, because of its perfect characteristics of ECCM (Electronic Counter-Countermeasures), anti-extra-low flight, AARM (Anti Anti-Radiation Missile), and anti-stealthy targets. It is significant for national defense to study this passive radar. Parameter estimation is a key technique in the passive radar system, since its precision influences the location precision directly. Based on the passive radar, the parameter estimation algorithms are deeply and widely studied in this dissertation. The main work and achivements of the dissertation can be summarized as follows:1. Based on the FM-broadcast, TV and radar signals, the intensity of the direct wave, the ground clutter and the target echo is analysed. The necessity of the direct wave and ground clutter suppression is proved.2. For restraining the direct wave and ground clutter, MinimumVariance Distortionless Reponse (MVDR) beam former and Adaptive Sidelobe Canceling(ASLC) algorithms are discussed, which paves the way for the parameter estimation.3. In the time domain, the (general) cross correlation and the improved algorithms for time delay estimation are studied, and in the frequency domain, the (general) phase data time delay estimation algorithm is also studied. Furthermore, a high precision FIR time delay estimation method based on the Least Mean Square principle and adaptive filter theory is discussed. Finally, the interferometer direction finding algorithm is analyzed.4. Based on the sensor array, joint the time-delay and DOA estimation algorithm based on ESPRIT and joint the time-delay, DOA, azimuth and elevation estimation algorithm based on PRO-ESPRIT are studied. In addition, the computer simulation and the performance analyse is discussed.5. Based on a temporal-spatial expanded virtual sensor array, a new method for joint estimation of Doppler Shift and DOA is proposed. By the cross correlation between the output of the sensor array, a temporal-spatial expanded virtual sensor array is built. Then the Doppler Shift and DOA are obtained basing on the conventional DOA Matrix method. The proposed method can resolve these problems, i.e, the number of multipath is smaller than the number of sensors, and the parameters of multipath signal with the same DOAs can not be estimated.