【摘要】 针对随机跳频合成宽带雷达体制以及高超声速应用背景,分析了大尺度多卜勒展宽效应、随机/非线性距离-多卜勒耦合效应及其对目标一维距离成像的影响,提出了基于多卜勒前置处理的实时递归记忆成像方法.该方法利用当前帧以及过去若干帧的回波数据得到当前帧的多速度通道一维距离像,在目标所处的速度通道附近进行前置的多卜勒波束锐化处理,抑制高动态/随机跳频合成宽带情况下的上述特殊效应所造成的目标一维距离像的发散;采用递归方式,每一帧的距离像都可以在前一帧距离像的基础上通过增加少量运算得到;引入记忆因子,进一步降低了存储及计算开销.理论分析及仿真结果表明:提出的成像方法可以有效改善成像质量,并且更容易满足高超声速应用情况下的高数据率实时成像需求.更多还原

【Abstract】 Aiming at the random-frequency-hopping synthetic wideband radar system as well as the application background of hypersonic vehicle platform, this paper analyzed the large scale Doppler broadening effect and random/non-linear range-Doppler coupling effect, as well as their influence on target range profile. Meanwhile,a method of real-time recursive and mematic imaging algorithm based on Doppler pre-processing was proposed. By this method,the multi-speed-channel range profiles were obtained by using the echo data of current frame and past frames, and Doppler-beam-sharpening was advanced to be performed at the speed channel of target and its adjacent channels to suppress the above special effects caused by high dynamic motion of platform and random frequency hopping in band-width synthesis. The recursion was used so that the range profiles of each frame can be obtained from those of the pre-vious frame through adding a few computations. The memory factor was adopted to further reduce the storage and computation costs. Theoretical analysis and simulation results show that the proposed imaging method can effectively improve the imaging quality, and can more easily meet the high-data-rate real-time imaging requirements in the hy-personic platform-borne application.更多还原