三维成像激光雷达线阵探测模式分析

摘要

以三维成像激光雷达对地面车辆目标探测为应用背景,采用线阵光电探测器并行接收的新体制来提高对目标成像的速度和实时性.按照对目标照射的激光辐射形式,总结出两种线阵探测模式:一种是激光多束发射模式,另一种是激光泛光发射模式.对这两种模式的机理、实现方式及优缺点进行了分析,并分别建立了两种模式下的激光雷达探测方程.采用信噪比和测距精度来分析两种模式的探测和测距性能.分别推导出了两种模式下信噪比与距离,发射功率与距离的关系表达式并进行了仿真.仿真结果表明,在相同距离和发射功率下,激光多束发射模式的回波信噪比更高;在相同距离和测距精度下,激光泛光发射模式需采用更高的发射功率.%A new kind of three-dimensional imaging laser radar is used to detect vehicle targets on the ground. Parallel linear array photodiode receiver is adopted by the laser radar to increase imaging speed. Two linear array detection modes are summarized. Their difference is the laser irradiation modes on the target;one is multi-beam laser transmitting mode, the other is floodlight laser transmitting mode. Mechanisms, implementation methods, advantages and disadvantages of the two detection modes are analyzed, and laser radar detection equations of the two detection modes are established. Signal-to-noise ratio (SNR) and ranging accuracy are adopted to analyze the detection and ranging performance of the two mades. Expressions of SNR versus range,laser transmitting power versus range are deduced, and simnulation is done. Simulation results show that,under the same condition of the range and laser transmitting power,SNR of multi-beam laser transmitting mode is higher;and under the same condition of the range and ranging accuracy,the transmitting power of floodlight laser transmitting mode is higher.