组合调制脉冲序列在扩展合成孔径雷达测绘带宽中的应用

Application of Combined Pulse-Series Coding in Wide-Swath SAR

针对合成孔径雷达(SyntheticApertureRadar,SAR)的距离模糊问题,本文提出组合调制脉冲序列的方法.特点是可以在距离向和方位向两维上对距离模糊进行抑制.其中,在方位向上需要使用本文给出的方位向相位调制法.由于产生距离模糊的回波一定是两个(或多个)在不同时刻发射出的脉冲的地面回波的叠加,可以在发射前对其分别进行不同的相移,然后从回波中修正前者的相移,而后者仍保留两个相移之差.这样就使后者多普勒历程被修改而前者不变.

This paper presents a method of combined pulse-series coding which is used to suppress range ambiguity in Synthetic Aperture Radar (SAR). This method can suppress, in both range and azimuth, range ambiguity of back-scattered signals. Specially, an azimuth phase shifting method is presented and used in this combined pulse-series coding method to suppress range ambiguity in azimuth. Azimuth phase shifting method is based on the fact that back-scattered signals with range ambiguity are generated by pulses of different eradiating time. Following this method, shift pulses by different phases firstly, and then reverse-shift the back-scattered signals by one of these phases. Consequently, the Doppler history of back-scattered signals will be disturbed except the desired signal whose shifted phase is completely reverse-shifted.