Based On Polarization Radar Anti-jamming Technology

As the improvement of science and technique, in modern electrical wars, the jamming that radar faced is more and more serious; the stealth of armament is higher and higher. The local wars in the end of 20th century indicated that under jamming, the function of traditional radar can not exert; the old way of detecting targets only use the information of amplitude, phase and Doppler frequency is out of use; finding new methods to improve the detection ability of radar is necessary.Besides amplitude, phase and Doppler frequency, polarimetric information is the fourth characteristic in the radar echo. Fundamental basic research and experimental results indicates that using polarimetric information can not only anti electromagnetic jamming, clutter jamming effectively but also improve the ability of stealthy targets detection, targets recognition and so on; the advantage of utilization of polarimetric information is more and more obvious. Using polarimetric information to improve radar's function has become the frontier of international radar system and technique; many developed countries have already used polarimetric technique in modern radars and have already made polarimetric radars. The utilization of polarimetric information in radar system has already formed some basis; modern wars have higher demands on the function of radars, so the research and utilization of polarimetric radar system must become top subject of our country. In recent years, as the mature of our country's polarimetric radar theory and the appearance of all kinds of new polarimetric furniture, doing research of polarization recognition, polarization reinforcement, polarization filtering, polarization cancellation and target recognition under the system of polarimetric radar have become possible.This dissertation mainly discussed polarization filtering, polarization cancellation and the application of polarization filtering in traditional side lobe cancellation radar under the system of polarization radar. First, the basic theory of polarization including the expression method of completely polarized wave and partial polarized wave and virtual polarization including the method to get the filtering parameters is introduced; then the adaptive polarization filtering, adaptive polarization cancellation and the application of polarization sensitive array in estimating the DOA and polarization parameters are discussed. The mainly works of this dissertation are as follows:1. On the basis of researching basic virtual polarization theory, real number weighed method and phase and amplitude weighted method is proposed to improve the performance of virtual polarization filtering.2. On the basis of polarization cancellation theory, a variable step size adaptive polarization cancellation iterative-filtering algorithm is proposed.3. On the basis of basic virtual polarization theory and three dimension polarization filtering, an adaptive three dimension polarization filtering algorithm is proposed.4. The filtering performance of simple polarization sensitive array is discussed, and an estimation method of signal DOA and polarization parameters based on ESPRIT algorithm is proposed.5. The utilization of polarization filtering in traditional side lobe cancelled radar is discussed.