Research On Distributed Array Radar Imaging Technology

Distributed array radar is a new radar system which combines multiple spatial distributed radars into an array and realizes coherent operation.Technique of distributed array radar imaging studied in this paper mainly refers to the imaging of space moving targets using distributed array radar laid on the ground.Different from the traditional Inverse Synthetic Aperture Radar(ISAR)which uses the motion of the target relative to the radar to form a synthetic aperture to image the target,the distributed array radar(DAR)adopts the idea of replacing the time diversity by the space diversity,and uses multiple radars to observe the target from different angles at the same time to obtain sampling data of the spatial spectrum of multiple observation angles.DAR can realize single snapshot imaging of space moving targets without coherent integration of echoes at different times.This avoids motion compensation,especially complex motion compensation of maneuvering targets in the process of imaging.In addition,using the two-dimensional distributed array deployed on the ground,and the three-dimensional observation of the target can be formed,and the three-dimensional sampling of the spatial spectrum can be obtained.Finally,the three-dimensional imaging of the target can be realized.At the same time,distributed array radar imaging also faces some problems,including array spatial error correction,appropriate imaging algorithm and array configuration optimization.To solve these problems,the second chapter introduces the radar imaging principle of space moving target from the perspective of space spectrum,and establishes the two-dimensional and three-dimensional imaging models of distributed array radar.In chapter 3,an imaging algorithm of DAR based on filter back-projection is introduced and a fast algorithm is proposed.The error model of the spatial array is established.The error correction method and the modified correction method are discussed.In chapter 4,the array optimization of DAR is discussed firstly.Two simple sparse array models and array optimization method based on the Genetic Algorithm(GA)are introduced.Then the super-resolution imaging of DAR based on signal sparse representation is discussed.The fifth chapter is the summary of the whole work and the prospect of future research.