为了扩展利用Chirp脉冲测距的灵活性和适用性,基于分数阶傅里叶变换特点,提出了一种运算量更小且更具扩展性的Chirp脉冲测距新方法,并导出了其离散距离估计子的解析表达式。分析了该距离估计子的离散精度和多目标分辨力,考察了多普勒频移所引起的测距误差,并对比了本文方法与脉冲压缩方法的主要性能参数。研究结果表明:本文方法在大时宽带宽积条件下具有与脉冲压缩方法相比拟的性能,且运算量约减少一半。最后,仿真验证了理论推导的正确性。
In order to expand the flexibility and serviceability of range-finding for Chirp pulse, a novel range-finding method is proposed for Chirp pulse based on the fractional Fourier transform, which has less computation complexity and more ex- pansibility, and the analytic expression of its discrete range-finding operator is derived. Thereafter the discrete accuracy and multi-target resolution as well as the influence from the Doppler shift are analyzed. Next, the main performance parameters are compared between the proposed method and the pulse compression method. It is found that both have almost the same performance accuracy if the product of pulse width and band width is large enough, while the computation complexity of the proposed method is reduced by half. Finally, simulations are made to prove the above theoretical analysis.