Research On Clutter Suppression Techniques For Coprime Space-time Compressive Sampling Airborne Radar

As the primary task to detect moving targets of airborne radar,clutter suppression plays an important role in the field of airborne radar.Meanwhile,space-time adaptive processing(STAP)technology has become a research focus in the field of radar since it is the key technology for clutter suppression and detection of moving targets.With the clutter suppression research as the background,this paper will focus on the research of airborne radar clutter suppression technology which is based on coprime space-time compressive sampling.The main research processes are as follows:1)This paper has studied the way to achieve space-time coprime sampling way,which can reduce the number of the transmitting pulse and antenna array,lower the complexity and cost of the radar system,and improve the reuse ability of the time dimension and capability of electronic count-countermeasures(ECCM)for the radar system.2)The research has introduced the coprime space-time compressive sampling into STAP technology,built the space-time coprime signal model and a space-time coprime clutter sparse model,and studied the directly STAP algorithm and sparse recovery STAP algorithm,both of which are based on coprime sampling.The simulation results show that compared with the same number of the pulse and antenna array of the traditional airborne radar,coprime sampling can achieve a better low speed of target detection.3)In order to make full use of the space-time degrees of freedom(DOFs)provided by the coprime configuration structure,the paper has proposed a STAP algorithm based on coprime virtual snapshot.First,the paper has analyzed the construction process of virtual space-time snapshot,and created the connection between the sample covariance matrix and virtual pulse and virtual array.Second,the virtual clutter plus noise covariance matrix is produced by the smoothing processing of the virtual space-time snapshot.Third,the research has replaced the original sample covariance matrix with the estimated virtual clutter plus noise covariance matrix to design the space-time filter,and thus to achieve the clutter suppression.Simulation results show that this STAP algorithm can effectively improve the system's ability to suppress clutter.The research introduces coprime space-time compressive sampling into airborne radar clutter suppression technology,which can lower the system's complexity and cost,and will provide the technical support for the research of a lighter,smaller,lower-cost,and less energy consumption airborne radar.