Research On The Method Of Solving Pulse-Doppler Radar Ambiguity

With the improvement of the weaponry performance and the increasingly complex battlefield environment,higher requirements are put forward for ground target detection based on airborne Pulse-Doppler radar.There are three working modes of airborne Pulse-Doppler radar,low,medium and high pulse repetition frequency,all of which can cause the problem of ambiguity which will lead to the wrong detection of the target.Based on the problems of range ambiguity and doppler ambiguity in the detection of wheeled vehicles in the mod of medium pulse repetition frequency,this paper mainly studies the methods to solve the above problems and the blind speed problem.The main contents of the paper are as follows:(1)The causes of range ambiguity,doppler ambiguity are deeply studied from the view of the measurement of the signal in radar and the ambiguity generate theory.The features of wheeled vehicle doppler signal are analyzed by building the model of wheeled vehicle,and the feasibility of detecting the target by the features is analyzed by building the clutter models.The prerequisite for solving the blind speed problem is given by the analysis of the features and the feasibility.(2)A modified algorithm,crossing-gate algorithm,based on the cluster algorithm and slide-window-cluster algorithm,is put forward to solve the problem of heavy computing burden,border effects,and the blind speed problem with the cluster algorithm and Sunzi algorithm in traditional methods.This algorithm solves the problem of heavy computing burden and border effects by crossing the slide window and solves the blind speed problem by using the features of wheeled vehicle doppler signal.The validity of the algorithm is substantiated by simulation experiments.(3)To avoid the difficulty in choosing the pulse repetition frequency in multiple pulse repetition frequency,an algorithm using single medium pulse repetition frequency,based on probabilistic data association,is put forward to solve the ambiguity problems.This algorithm mainly makes use of the ideas and methods of probabilistic data association to sole the doppler ambiguity and shifts the ambiguous range to the prediction of measurement to solve the range ambiguity.The result of simulation experiments shows that the algorithm can sole the range ambiguity and doppler ambiguity effectively.