针对发射波形为相位编码，探测低速运动目标时存在的模糊度函数旁瓣峰值过高，容易淹没微弱目标的问题，提出了在特定区域最小化模糊度函数旁瓣级的多相编码波形设计优化算法。该算法利用低速运动目标多普勒频移很小的特点，对模糊度函数进行简化，提出了离散模糊度函数的概念，在此基础上将模糊度函数峰值附近旁瓣级的最小化转化为离散模糊度函数峰值附近旁瓣级的最小化问题，并利用循环算法进行相位编码的设计。计算机仿真结果表明，所提出的波形设计方法能够有效抑制离散模糊度函数原点附近的旁瓣级，提高探测系统对微弱低速运动目标的检测能力。
When detecting low velocity moving targets,Polyphase pulse has high peak sidelobe that will cause the loss of weak target detection.To solve this Problem, a waveform design method for reducing sidelobe level in a particular area of ambiguous function(AF) was proposed.This method take advantage of the low velocity moving targets with very small doppler frequency shift, simplified the ambiguous function.we put forward a conceptual for Discrete Ambiguous Function(D-AF).The foregoing discussion implies that by minimizing the correlations of AF, we equivalently minimize the D-AF sidelobes. The minimization problem can be solved by the cyclic algorithm described in this paper. Numerical simulation showed that the proposed algorithm sidelobe suppression for designing sequences with a thumbtack-shaped discrete-AF near the origin of the delay-Doppler plane effectively, meanwhile, it improved the detection ability of weak target detection.
2019,41(4): 124-128 收稿日期：2018-05-25
DOI：10.3404/j.issn.1672-7649.2019.04.024
分类号：TN957.51
作者简介：周飞(1988-),男,助理工程师,研究方向为水声信号处理
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