Moving Target Detection And Parameter Estimation Based On Distributed Sar

Synthetic Aperture Radar works in a unique way and can satisfy the demand of investigation system in modern society. As a kind of new radar implementation, its superiority is highlighted. For distributed small satellite SAR moving target parameter estimation problem, this paper discussed systematically. Distributed small satellite SAR moving target space-time model is proposed firstly, parameter estimation problems in case of 2D acceleration moving target and 3D moving target are discussed, and this paper analyzes its characteristics and processing methods respectively.For 2D acceleration moving target, the slant distance equation is more complex than uniform motion, the second order Taylor expansion can’t satisfy the required accuracy, in order to realize the estimation of 2D acceleration moving target, the estimation of higher order of phase factor is needed. Product High-order Ambiguity Function is a powerful way to estimation polynomial phase, however in under the background of spaceborne SAR its estimated parameter precision is slightly poor, unable to get moving target motion parameters effectively by doppler parameters. So this paper proposes a high precision frequency matching estimation method and the combination method with PHAF can estimate the parameters of acceleration moving target effectively.The main difference between 3D moving target parameter estimation and horizontal motion parameter estimation is the slant distance equation of coupling of the former is more serious, how to effectively separate the motion parameters of moving targets in all directions is a question. This paper, by means of parameter fitting, fits the azimuth echos of all distributed satellites, through the way of linear programming to work out the parameters, therefore parameter fitting has a greater influence on the accuracy of estimated results. This paper estimates the 3D moving target parameters with the combination method of Fractional Fourier transform and HRFME, it can realize high accuracy of parameter estimation.