一种改进的OTHR自适应海杂波抑制方法

Modified adaptive ocean clutter suppression approach in OTHR

海杂波抑制严重限制天波超视距雷达(over-the-horizon radar,OTHR)系统对低速舰船目标检测能力的主要原因之一。针对自适应海杂波抑制方法中当杂波与目标多普勒频率接近时存在目标谱峰分裂或目标谱峰偏移的问题,提出一种采用运动目标显示(moving target indication,MTI)与基于特征值分解的自适应杂波抑制相结合的改进的特征值分解(modified eigen-value decomposition,MEVD)海杂波抑制方法。该方法通过MTI滤波器抑制目标谱峰内杂波,之后通过自适应抑制方法抑制其他杂波,具有同时抑制一阶和高阶海杂波的能力,提高了目标信杂噪比,有助于提高OTHR对舰船目标的检测性能。理论分析、仿真实验和实测数据处理结果均验证了MEVD方法的有效性。

The ocean clutter is one of the significant factors that limit the detection performance of the over-the-horizon radar（OTHR） system for slowly moving ship targets.Aimed at the problem that when the Doppler of a target is not significant to allow discrimination in Doppler,the target peak can be spilt or deviate from the true position,a modified eigen-value decomposition（MEVD） approach,which combines the moving target indication（MTI） and an adaptive approach based on eigen-value decomposition is adopted.In MEVD approach,the clutter near target is suppressed with MTI and other clutters are suppressed with adaptive approach.Meanwhile,this approach is able to suppress not only the first order but also high order ocean clutter,so the signal-to-clutter-plus-noise ratio is increased,which helps to improve detection performance of OTHR.Theoretical analysis and the results of simulations and real data processing indicate the effectiveness of MEVD approach.