运动直升机旋翼的微多普勒特性分析

激光雷达由于其极高的探测灵敏度,使其在探测过程中具有明显的微多普勒效应。目前,对直升机旋翼微多普勒的研究大部分是在直升机处于悬停状态的基础上,但是在实际情况中直升机是在做各种运动。利用PO 法对直升机旋翼叶片的RCS 进行了计算,建立了直升机旋翼回波的微多普勒模型。并基于该模型,以AH-64 武装直升机为例,分别对作直线运动和俯仰运动的直升机旋翼的微多普勒效应进行了仿真和数值分析。研究结果表明,通过对直升机旋翼的距离单元曲线以及微多普勒频谱的分析可以初步判断直升机的运动状态,为下一步运动直升机的微多普勒识别提供了参考和借鉴。

Micro- Doppler analysis of moving helicopter's rotor blades

Because of laser radar having extremely high detection sensitivity, the micro-Doppler effect is obvious in laser radar detection process. At present, the study of micro-Doppler of rotor blades is almost based on the hovering helicopter, however, helicopters are taking various motion in the actual condition. In this paper, the RCS of a helicopter rotor was calculated, and a micro-Doppler model of a helicopter rotor was established. Based on the model, taking the AH-64 armed helicopter for example, the micro-Doppler effect of the rotor blades in radar detection process was simulated and calculated, of which was taking the uniform linear moving and the face upward moving. The results show that the motion state of the helicopter can be judged primarily through analyzing the range profiles of the distance and the frequency spectrum of the micro-Doppler effect of a helicopter's blades in radar detection process, which provides some reference for moving helicopter identification by micro-Doppler.