STAP On The Suppression Of Broadening Sea Clutter

The first order sea clutter of HF sky-surface radar represent apparent space-timecoupling characteristics and Doppler broadening because of the influence of biostaticangle and ionospheric disturbance, which will lead to the submerging of the shipmoving slow. In this paper, the angle-Doppler distribution of broadening first order seaclutter is analyzed according to the HF sky-surface radar operational principle, andSpace Time Adaptive Processing is used to suppress the broadening sea clutter.Firstly the radio wave path of the HF sky-surface system is analyzed, and thespace-time distribution of first order sea clutter is simulated under the consideration ofbiostatic angle and ionospheric disturbance, and the theoretical distribution coincideswith the measured distribution.Based on the simulation model, the performance of full STAP anddimension-reduced Joint Domain Localized on suppression of first order sea clutterdisturbed by ionosphere. It shows that JDL algorithm can effectively suppress first orderand find the submerged target with low calculated quantity and training sample data.The influence of ionospheric disturbance on the space-time coupling characteristics andperformance reduction of JDL algorithm is analyzed quantitatively.JDL algorithm is used in the target detection in the real complex background. It isproposed that the interested range bin is used to estimate the clutter covariance matrixafter eliminate the target information may exist, and the results show that this methodcan raise the clutter suppression performance of the interested local. Taking the outputof range as the weight of training sample data, and using the weighted data to estimatethe clutter covariance matrix is also proposed. Considering the theoretical space-timedistribution of first order sea clutter as the knowledge to produce deeper null in theclutter region where not eliminate the target information.The proposed JDL algorithmcan effectively improve the target and clutter power ratio in the real complexbackground.