Research On Discrimination And Parameter Estimation Of Multiple Targets In The Air For Missile-borne Radar

In some military applications such as attack on formation target, aerial defense and antimissile actions, guided weapons face war conditions consist of complicated factors such as target formation and electronic interference and cajolery. If precision guided weapons want to hit the target precisely, the problem of resolving multi-target must be resolved. Supported by project"research on XXXX Signal Processing technology", this paper researches on discrimination and parameter estimation of multiple targets in the air. The work of the paper is shown as follows:Firstly, this paper reviews the background of resolving multi-target in beam of the radar. The current development of the technology of resolving multi-target in and abroad is introduced, and the key technologies and technology difficulties of radar signal processing method available to develop multi-target resolving algorithms are indicated. Also, the trend of multi-target resolving technology is presented. Secondly, the kinematical model of the air-to-air missile attacking the formationtarget is established. The separability of formation target in the course of the missile hitting the target is given through theoretical analysis and simulation experiments. Meanwhile, influence of factors such as guidance law on separability is presented through simulation. The research result of the separability of formation target provides basis for developing multi-target resolving algorithms.Thirdly, a method based on the two dimensional angle information is presented. In allusion to the undulate character of the amplitude of formation target echo signal, the signal model of multi-target and the principle of detecting the presence of formation target are introduced, and a method base on GLRT using the azimuth and vertical angle information is presented. Simulations prove its effectiveness.A modified maximum likelihood method of estimating angles is presented. And estimations base on MM and maximum likelihood are analyzed. In allusion to the requirement of angle estimation accuracy, optimizations are made to the estimating results. Simulation results verify the effectiveness of the method of estimation and optimization.The time-frequency analysis method is used to resolve multi-target in allusion to the nonstationarity of the echo signal of formation target. A new method of estimating parameters of multi-target is presented. The method firstly detects number of the formation based on entropy. Then, in consideration of the Hough Transformation's character of high accumulation for lines in image detection applications and the advantage of WVD in time-frequency analysis, a transformation called WHT is applied to estimate parameters of multi-target's echo signal. Simulation experiment verifies its effectiveness to estimate parameters of multi-target. Simulations verify its effectiveness of detecting the number of aircrafts and parameter estimation of the formation.