对影响定向通信系统天线波束指向误差的因素进行了分析，给出了一种特殊情形下波束指向误差与 姿态角的关系式，同时给出了一般情形下基于最小二乘估计的波束指向误差与姿态角关系的推导方法。给出的 关系式和方法对分析定向通信系统波束指向误差提供了理论依据，有助于评估定向通信系统的波束对准情况。

Factors which affect the pointing error of antenna beam are analyzed in directional communication system. The relation between the pointing error of antenna beam and attitude angles is given for a special situation, meanwhile, a deduction method to obtain the relation between the pointing error of antenna beam and attitude angles based on least square estimation for a general situation is given. The relation and the method presented provide theoretical basis to analyze the pointing error of antenna beam for directional communication system, the results are good for estimating the situation of beam aim for directional communication system.