在进行偏移迭加或迭加偏移时,事先都需要选择偏移范围。已经有几种计算偏移范围的方法。但是,有的物理意义不够清楚,有的仍然包含一、二个试验参数,有的甚至包含了速度这种运动学的物理量。本文结合观测系统提出偏移迭加或迭加偏移的偏移范同的一种新的计算方法。 When performing offset overlay or overlay offset, the offset range must be selected in advance. There are several ways to calculate the offset range. However, some of the physical significance is not clear enough, some still contain one or two experimental parameters, and some even include the physical quantity of the kinematics of speed. In this paper, we propose a new calculation method of offset co-ordination with offset superposition or superposition offset combined with observation system.