提出了一种四Gm-APD单次探测的激光雷达系统,该系统采用2×2的光纤阵列同时接收回波脉冲,利用四通道实时比对得到目标的距离信息。计算了该系统探测概率、虚警概率和测距精度,并与传统单Gm-APD四次累积探测激光雷达系统进行相互比较。结果表明,四Gm-APD激光雷达系统不仅能够使探测速度提高到4倍,其探测性能也都明显优于单Gm-APD四次累积探测的激光雷达。探测概率从60.6%提高到了91.6%,虚警概率从1.9%下降到了0.2%,测距精度从1.771 m提高到了0.440 m。最后,分别对两个系统进行了64×64像素的距离像仿真,仿真结果验证了该方法的正确性。
A photon counting imaging lidar system with four Geiger-mode avalanche photodiode (Gm- APD) detectors was proposed. A 2×2 optical fiber array was used in the system to receive echo pulse simultaneously. The distance of the target was obtained through the signals of the four channels in real time. The detection probability, the false alarm probability and the range accuracy of the lidar system were calculated. Comparing with the single Gm-APD system, the detection performances were all significantly improved the detection probability was improved from 60.6% to 91.6%, the false alarm probability was restrained from 1.9% to 0.2% ,and the range accuracy was improved from 1.771 m to 0.440 m. By mean of the 64×64 pixels range imaging simulations of the single Gm-APD system and the approach in this paper, the validity of the theoretical derivation is demonstrated.