在某些数字脉冲压缩体制的雷达应用中,观测者特别关心距离目标特定范围内的距离旁瓣特性,比如群目标环境或干扰环境下的目标检测,此时可以充分利用滤波器系数的自由度,在特定距离区间内实现观测者所需的超低旁瓣,从而防止目标遮蔽或者达到反干扰、距离超分辨等目的。文中把旁瓣抑制过程建模为线性约束最小方差(LCMV)滤波过程,通过对特定距离区间的旁瓣电平施加附加约束,实现积分旁瓣电平最小意义下的最优距离旁瓣赋形滤波器,进一步通过非线性最优化方法可获得最优滤波器系数。仿真实验处理结果验证了算法的有效性。文中的讨论基于时域滤波,其结论同样适用于频域和空域。

In some digital pulse compression radar applications, what interests the user is the range sidelobe characteristics in some specified range region, like target detection in group target environment or jamming environment. In this case, freedom degree of the filter can be used to obtain desired ultra-low sidelobe level in specified range regions so as to prevent target from obscuring or achieve the purpose of anti-interference or range super-resolution. In this paper, sidelobe reducing process is modeled as linear constrained minimum variance (LCMV) filtering process with additional constraints for sidelobe level in specified range region, so as to obtain an optimal range sidelobe shaping filter in the sense of minimum integrated sidelobe level. Then the optimal filter factor is obtained by nonlinear programming method. The effectiveness of proposed algorithm is shown via simulation experiments. Although the algorithm is proposed in time-domain, it is applicable to the implement of frequency-domain and space-domain.

TN958