双基FMCW宽带雷达微多普勒特征分析与误差因子补偿

对双基调频连续波(FMCW)宽带雷达旋转目标的微多普勒效应进行了研究。首先建立了双基FMCW宽带雷达中的旋转目标模型,推导得出了旋转目标的微多普勒效应表达式,并通过分析目标脉内微动对一维距离像的影响,得出了一次误差项会引起一维距离像的走动和峰值偏移、二次误差项会引起一维距离像的展宽、同时双基角也会对目标微多普勒特征曲线的最大频偏产生调制等结论。在此基础上,进一步提出了利用最小熵准则对误差因子进行补偿的方法。仿真分析表明:该方法能够较精确地估计二次误差项的系数,有效地补偿目标微多普勒效应的误差因子,并具有良好的抗噪性能。

A Micro-Doppler Feature Analysis and Error Factor Compensation in Bistatic FMCW Wideband Radar

The micro-Doppler effect of rotating target is studied in bistatic frequency modulation continuous wave (FMCW) wideband radar in this paper. Firstly, the model of rotating target is established in bistatic FMCW wideband radar, and the expression of micro-Doppler effect is derived. Then, the conclusion is deduced from the previous that the primary error term causes one-dimensional range profile walk and peak deviation, and the quadratic error term causes the one-dimensional range profile widening, also the maximum of frequency deviation in micro-Doppler feature curve is modulated by the bistatic angle according to the analysis of the influence caused by micro-motion during the pulse repetition interval (PRI) on one-dimensional range profile . Finally, the error factor compensation approach based on minimum entropy principle is proposed. The simulation analysis indicates that the use of the method can estimate the coefficient of the quadratic error term in precision and can compensate the error factor of the micro-Doppler effect effectively and is good in anti-noise performance.