基于光纤激光器的相干多普勒激光雷达

Coherent Doppler laser radar based on Er-doped fiber laser

介绍了一种基于掺铒光纤激光器的相干测速激光雷达,该雷达具有成本低、可靠性高和结构新颖的特点。雷达系统的光路完全采用通信用光纤器件构成,单模光纤耦合器用作分光器和混频器,偏振无关的光纤环形器用作光学天线收发开关,所有光路器件采用单模光纤连接。雷达系统采用频谱分析法进行鉴频获取中频信号的中心频率。研制了原理样机并进行测速试验,系统可以探测的最小速度小于0.4 mm/s,测速精度优于0.1%,输出非线性度小于70×10^(-6)。

A low-cost, novel and robust coherent Doppler laser radar （CDL） based on Er-doped fiber laser is presented. Reliable optical fiber components and instruments for optical communication are used to build this system. All devices of optical circuit are connected by single-mode fibers, which make the system reliable and setu Parrangement flexible. Spectrum estimation method based on efficient digital signal processing technique and fast Fourier transformation （FFT） are utilized to determine the location of the peak. A prototype was developed and experiments were performed on a moving hard target. Experiment results indicate that the minimum detection velocity is below 0.4 mm/s, and the resultant nonlinearity calculated by least square method is less than 70 × 10 ^-6.