瞄准偏差和光束抖动是光束瞄准系统中的两个最重要的误差。对以高斯光束和高斯抖动为基础的光束瞄准目标时产生的光回波信号进行数学建模；结合极大似然估计算法理论，建立并完善了基于回波信号的光束瞄准误差估计模型；并编写程序实现了Monte Carlo模型仿真，搭建了实验室平台。仿真和实验结果表明，极大似然估计算法表现出了优良的性能，能够同时准确地估计出瞄准偏差和光束抖动，信号样本越大其估计精度越高，且实验结果和仿真结果吻合得很好。在此基础上，根据实时偏差估计实现了实验室光束闭环瞄准实验。

Boresight and jitter are two fundamental pointing errors for a laser pointing system. With the theory of maximum-likelihood estimation, a laser pointing system model is setup and consummated based on a Gaussian far-field irradiance profile and a Gaussian beam jitter model. The estimates are gained by use of return photon counts reflected from an intended target. Then, a Monte Carlo simulation is programmed and a laboratory experiment is performed. Both the simulations and experimental results demonstrate that the performance of the maximum-likelihood estimator is excellent and improves with the increasing number of shots. With this method, the boresight and jitter can be obtained simultaneously. What′s more, the further study finds that the experimental results agree well with the simulation results. Based on these excellent performances of the estimator, a closed-loop laser pointing experiment is exhibited in laboratory.