Study Of Space-domain Reduced-rank Of Space-Time Adaptive Processing Approach For Airborne Radar

Clutter suppression is critical to airborne early warning surveillance sensors. In addition to the conventional techniques such as low sidelobe antennas and displaced phased center antenna(DPCA), there has been great interest in space-time adaptive processing(STAP) because it can suppress clutter effectively and improve the detection performance of airborne phased array radar evidently. The research on STAP began in 1973 and has been performed for more than 20 years. The computation load and the implementation complexity of full rank STAP are too great to be accepted and it is really very difficult to obtain enough samples to estimate the covariance matrix. In order to use space-time adaptive processing technology in practice, we must reduce the rank.In the thesis, we describe the clutter character of airborne radars and the principles of the STAP firstly, and then we investigate the space-domain reduced-rank. The investigation of space-domain reduced-rank contains two parts, one is rank reduction within element domain and the other is rank reduction within beam domain. In the studying of rank reduction within element domain at the third chapter, we discuss the methods of subarray division by regular and irregular means and in this foundation a new method of subarray division is presented. In this chapter, a three dimensional space-time adaptive processing method is investigated as well. In the fourth chapter, we investigate rank reduction within beam domain. In this chapter we discussed the principle of rank reduction within beam domain and investigate performance of the locally multiple beam reduced-rank in detail.