针对光电跟踪仪伺服系统设计所关心的视频处理系统的频域特性参数，在频域内分析了视频处理系统的理论模型，并设计了一种频域测试方法，借助于光电跟踪仪伺服系统速度环路，通过在频域扫频的方式，利用信号之间相位、幅值对比间接测量了视频处理系统的时间滞后和带宽，以50 Hz视频处理系统为例，所测带宽为19.452 Hz，时间滞后为40.57 ms。

The EO tracker servo system design focuses on the frequency-domain characteristic parameters of the video processing system.We analyzed the theoretical model of the video processing system in the frequency domain, and designed a novel testing method. By using the velocity loop of the optical tracker servo system，through the frequency sweep in frequency domain and the contrast of the signal phases as well as the amplitudes，we indirectly measured the time lag and bandwidth of the video processing system. Taking a 50 Hz video processing system for instance,the tested bandwidth is 19.452 Hz, the time lag is 40.57 ms.