基于高阶奇异值分解的天波雷达海杂波抑制算法

Over-the-horizon radar sea clutter suppression algorithm based on higher order singular value decomposition

天波超视距雷达的监测范围非常广,实际中经常要求其在短相干积累时间(Coherent Integration Time,CIT)条件下检测舰船目标,然而短CIT导致多普勒分辨率降低,很难从强大海杂波中检测出舰船目标.针对上述问题,提出了基于高阶奇异值分解(Higher-Order Singular Value Decomposition,HOSVD)子空间估计的海杂波抑制算法.利用舰船目标所在距离单元的回波数据建立Hankel张量,然后采用HOSVD求解Hankel张量的海杂波子空间和目标子空间,应用正交投影方法将Hankel张量映射到目标子空间以抑制海杂波.仿真结果表明:该方法与现有子空间类海杂波抑制方法相比,提高了主旁瓣比和信干噪比.

Over-the-horizon radar（OTHR） has rather wide scope of monitoring,which is often required to detect ship target under the conditions of short coherence integration time（CIT）in practice,however, short CIT causes low Doppler resolution,leading to the difficulty of detecting ship targets from the strong sea clutter. To solve the above prob- lem, sea clutter suppression algorithm of subspace estimation based on higher order sin- gular value decomposition（HOSVD） is proposed. Firstly, Hankel tensor is established by echo data of the distance unit containing the ship target. Then the sea clutter sub- space and target subspace of that tensor are solved by HOSVD. Finally,in order to sup- press sea clutter,Hankel tensor is mapped to the target subspace by orthogonal projec- tion method. It shows in the simulation results that the signal to clutter plus noise ratio （SCNR） and the peak sidelobe level ratio（PSLR） are enhanced, compared with the existi- ing sea clutter suppression method of subspace.