基于零陷展宽的双基地声纳直达波抑制算法

双基地声纳系统中存在目标信号与直达波干扰混叠且两者高相关的情况,常规的自适应抵消法因此失效。在双基地声纳系统配置已知的前提下,提出一种基于零陷展宽技术的多约束最小方差直达波抑制算法。该方法通过施加线性约束对特定方向的干扰进行抑制,并针对直达波干扰方位存在扰动时,多约束最小方差算法性能急剧下降的现象运用零陷展宽的方法对算法加以改进。基于零陷展宽的多约束最小方差算法直观、快捷。仿真及实验数据处理的结果表明,在直达波干扰方位大致可知的情况下,该算法能够对直达波进行有效抑制,且对直达波的方位估计误差具有稳健性。

A direct path interference suppression algorithm of bistatic sonar based on null broaden method

The direct path interference is highly correlated with the target signals in the bistatic sonar system, so the common adaptive canceUation algorithm is ineffective. A multiple constrained minimum variance algorithm based on null broaden method is given under the condition of knowing the incident direction of direct path interference. The algorithm suppresses the direct path interference by imposing linear constraint, but it is sensitive to the estimation error of interference incident direction. So a method of broadening the null artificially is put forward to improve the algorithm. The multiple constrained minimum variance algorithm based on null broaden method is intuitive and rapid. The data processing results of computer simulation and lake experiment show that the improved algorithm can eliminate the direct path interference effectively and keeps valid when the incident direction of direct path interference is incorrectly estimated.