摘要
星载多发多收合成孔径雷达(MIMO-SAR)可以解决方位向高分辨和大测绘带之间的矛盾。为了在扩大测绘带宽度的基础上进一步实现距离向超高分辨,首先选用正交频分线性调频信号(OFD-LFM)作为发射信号形式,对MIMO-SAR的发射体制进行了初步设计;然后针对大带宽、宽测绘带对成像算法的限制,选用精确度高的距离徙动算法(RMA)对回波数据进行处理,给出了结合空频域带宽合成的RMA成像流程,相比时域带宽合成方法,在确保成像精确性的同时,文中的成像流程计算步骤更少,运算量更低,大大提高了计算效率。
Spaceborne multiple-input multiple-output synthetic aperture radar(MIMO-SAR) can resolve the conflict between high azimuth resolution and wide swath. In order to obtain ultra-high range resolution, in this paper we use orthogonal frequency division linear frequency modulation(OFD-LFM) waveform as the emitting signal of MIMO-SAR, and design the system's emitting mode primarily. For the restraints brought by wide bandwidth and wide swath to the imaging algorithm, we choose the high-precision range migration algorithm(RMA) to deal with the echo data. An imaging flow using RMA combined with synthetic bandwidth in spatial frequency domain is proposed. Compared with the time domain synthetic bandwidth method, the proposed imaging flow not only insures the image precision but also has fewer operating steps and lower computational load, which greatly improves the computing efficiency.
出处
《雷达科学与技术》
2011年第5期409-415,429,共8页
Radar Science and Technology
关键词
合成孔径雷达
多发多收
超高分辨
大测绘带
距离徙动算法
synthetic aperture radar(SAR)
multipIe-input multiple-output(MIMO)
ultra-high resolution
wide swath
range migration algorithm(RMA)