一种基于线性规划的频率编码旁瓣抑制方法

Side Lobe Suppression of Frequency-Coded Signal Based on Linear Programming

摘要:

频率编码信号具有较好的距离-多普勒分辨率、优良的低截获和抗干扰能力,但其旁瓣较高,不适用于检测动态范围大的海面多目标场合。采用失配滤波器法降低旁瓣电平会导致旁瓣宽度展宽,强目标旁瓣宽度展宽,反而遮盖了附近的弱目标。采用脉间码型捷变法,旁瓣抑制效果达不到实际应用要求。文章结合着 2种方法,设计一种复合的旁瓣抑制方法。仿真结果表明,在相同信噪比损失和旁瓣宽度的情况下,本方法比失配滤波器法,峰值旁瓣比提高了 7.5dB；在积累相同的脉冲个数情况下,比脉间码型捷变法则提高了 18dB。

Abstract:

Frequency-coded signal has high range-doppler frequency, low probability interception property and good antijamming capability. However, it has the disadvantage of high side-lobe, which makes it unsuitable for detecting great dy?namic range targets on sea surface. Traditional mismatched filter is designed to suppress side-lobe, yet it also broadensthe side-lobe width. The broadening side-lobe of strong target may submerge weak targets beside it. The method of inter-pulse code agility also can suppress side-lobe,but it can’t satisfied practical application. Therefore, a novel method calledcompound side-lobe suppression is proposed in this paper, which combines the two kinds of method above. The experi?ment results show that the peak side-lobe ratio of new method is 7.5dB higher than mismatched filter method under thesame side-lobe width and same signal-noise ratio loss; and it’s also 18dB higher than inter-pulse code agility method when accumulating the same number of pulses.