受空间所限，激光通信地面测试平台与被测终端之间的距离远小于实际通信距离，导致测试平台光机等器件产生的后向散射杂光进入被测终端，从而严重影响被测终端的测试性能。从被测终端与测试平台间的光学干扰问题出发，本文研究了被测终端与测试平台间隔离度的关系，分别设计了卡塞格林和离轴三反光学天线，并根据杂散光传输模型，采用杂散光分析软件分析了光学天线结构形式及表面粗糙度两方面对隔离度的影响。分析结果表明，采用离轴三反光学天线时的隔离度明显高于卡塞格林光学天线，且隔离度随着光学表面粗糙度的减小而增大，当光学表面的粗糙度达到0.892 nm时，隔离度可达?86.22 dB。最后，推导了ABg模型与Harvey模型参数间的关系，并根据粗糙度与TIS计算公式，得出粗糙度分别为0.7 nm及0.5 nm的ABg模型参数，它们的终端间隔离度分别为?94.39 dB和?97.3 dB，实现了?90 dB的隔离度指标。

Coulomb potential may induce a significant angular offset to the two-dimensional photoelectron momentum distributions for atoms subject to strong elliptically polarized laser fields. In the attoclock experiment, this offset usually cannot be easily disentangled from the contribution of tunneling delay and poses a main obstacle to the precise measurement of tunneling delay. Based on semiclassical calculations, here, we propose a method to extract the equivalent temporal offset induced solely by Coulomb potential (TOCP) in an attoclock experiment. Our calculations indicate that, at constant laser intensity, the TOCP shows distinctive wavelength dependence laws for different model atoms, and the ratio of the target atom’s TOCP to that of H becomes insensitive to wavelength and linearly proportional to (2I_p) ^3/2, where I_p is the ionization potential of the target atom. This wavelength and I_p dependence of TOCP can be further applied to extract the Coulomb potential influence. Our work paves the way for an accurate measurement of the tunneling delay in the tunneling ionization of atoms subject to intense elliptically polarized laser fields.