Study On Space Time Adaptive Processing For Wide-area Moving Target Indication

In airborne moving target detection (MTD) radar systems, the primary goal is to suppress the ground clutter effectively. Conventional radar system with single antenna fails to detect the slowly ground moving targets whose signal may be totally submerged in that of mainlobe clutter. Space time adaptive processing (STAP) is a leading technique for improving detection performance of airborne or spaceborne radar in strong clutter environments. This dissertation focuses on the moving target indication (MTI) techniques based on STAP for wide-area traffic monitoring and battlegrounds information collection .Chapter 1 is the introduction. It outlines the histories of airborne radar MTD techniques briefly. The research background and main contents are also addressed.In chapter 2, displaced phase center antenna (DPCA) technique is studied. The principle of DPCA and tow kinds of modernistic applications are introduced briefly, followed by the detailed discussions of tow∑△-DPCA techniques ,i.e., the time and frequency domain∑△-DPCA .In chapter 3, the principle of STAP is analyzed. The characteristics of target, noise, jammer and clutter are studied based on the construction of signal model concerning radar echoes, followed by investigation of the covariance matrixes of noise, jammer and clutter.In chapter 4, reduced dimension and reduced rank STAP are studied. As a standard reduced dimension STAP algorithm,∑△-3DT decreasing computational load and sample support are investigated herein, in which the transform matrix for dimension reduction is determined by target steering vector. However ,∑△-3DT reduces dimension without using information of the collected data, which may result in the lack of flexibility. Hence the∑△-MNE algorithm, as a reduced rank STAP, is studied further in this chapter.In chapter 5, the reduced-dimension 3DT-STAP algorithm used for a three-channel airborne system is studied. The universal digital signal processing system (TS-C43) exploited by Transtech Inc is applied to process the measured data collected by a three-channel airborne radar for moving target detection. In this chapter the detailed processing procedure and application programs procedure are investigated, which are proved to be of practical value for the realizations of other STAP algorithms in the engineering. In chapter 6, the work of this thesis is concluded and the future work is pointed out.