从Gm-APD的泊松统计的雪崩探测模型出发,在长死时间情况下,提出了一种提高Gm-APD激光雷达探测性能的方法。利用衰减片控制信号和噪声的强度,实现了多脉冲探测Gm-APD激光雷达的探测概率、虚警概率和测距误差的提高。研究结果表明:随着衰减片透过率的变化,探测概率存在最大值,测距误差存在最小值,将衰减片透过率控制在0.33~0.20之间,探测距离为1.5 km时,探测概率能提高1倍,测距误差可以从m量级提高到cm量级。
Based on the Poisson probability model of Gm-APD, in the long dead-time case, a new approach to improve the detection performances of Gm-APD lidar was proposed. The formulas of detection performances (detection probability, false alarm probability, and range error) of multiple pulses detection Gm-APD lidar were obtained and analyzed. By using an attenuator to control the intensity of signal and noise, the detection and false alarm probabilities, and range error of multiple pulses detection Gm-APD lidar were all improved. With the change of transmissivity of attenuator, the detection probability has a maximum, and the range error has a minimum. While the target is at the distance of 1.5 km, with the increase of the pulse number and the controlled transmissivity of attenuator between 0.33 and 0.20, the detection probability can be doubled with the sharp decline in false alarm probability, and the range error can be decreased from meters to centimeters.