CAJ | 학술논문

在线性调频步进信号中,相邻子脉冲间的频谱重叠将导致脉冲压缩后出现较强的栅瓣,弱小目标可能被强目标的栅瓣所遮掩.为此,该文通过分析线性调频步进信号自相关函数的组成,提出一种新的对子脉冲加权后信号进行切趾滤波的栅瓣抑制方法.通过对子脉冲频谱采用不同的窗函数加权,改变子脉冲信号自相关函数旁瓣符号,进而改变调频步进信号栅瓣位置处的符号,通过多组不同加权结果的对比,利用切趾滤波的思想实现栅瓣的识别与抑制.数值仿真和实际图像处理证实了该方法的有效性.
재선성조빈보진신호중,상린자맥충간적빈보중첩장도치맥충압축후출현교강적책판,약소목표가능피강목표적책판소차엄.위차,해문통과분석선성조빈보진신호자상관함수적조성,제출일충신적대자맥충가권후신호진행절지려파적책판억제방법.통과대자맥충빈보채용불동적창함수가권,개변자맥충신호자상관함수방판부호,진이개변조빈보진신호책판위치처적부호,통과다조불동가권결과적대비,이용절지려파적사상실현책판적식별여억제.수치방진화실제도상처리증실료해방법적유효성.
In the frequency-stepped chirp signal, the frequency spectrum overlap between the neighboring sub pulses would lead to grating lobes in the result of range compression. The weaker points may be masked or distorted by the grating lobes of strong points. In this paper, a grating lobe suppression algorithm is proposed based on apodization filtering. By weighting the spectrum of sub pulse signals with different functions, the apodization could be done through the results and the grating lobes could be eliminated. Numerical simulations and real data experiment confirm the effectiveness of the proposed algorithm.