信噪比对高速视频系统作用距离制约的分析

SNR limitation of high-speed visual image system detection distance

研究了在靶场测试中能否用高速视频系统替代高速摄影完成记录功能的问题,讨论了这一问题涉及到的成像视场、信息量、作用距离等技术指标。依据系统作用距离的判据对高速摄影系统和视频系统的作用距离进行了分析。分析表明,视频系统的信噪比、分辨率、帧频之间存在相互制约的关系而不能兼顾,当帧频、分辨率提高时,信噪比则下降,对高速、高分辨视频系统,信噪比是限制系统作用距离的首要因素。由于信噪比的限制,高速视频系统达不到高速摄影的作用距离。

Whether a high-speed visual image system can do high-speed photography to satisfy the recording need is a hot topic for researchers in the range test field. This involves several issues, such as image field, detection distance, and information acquisition capability, and detection distance is the core issue for necessary consideration. It is concluded from the analyses of the factors having effect on detection distance in the two systems that, in a high-speed and high resolution visual image system, there is a contradiction between frame rate, resolution, and SNR. SNR decreases as frame rate and resolution increase, and SNR is the primary factor which limits the system detection distance, and therefore, a high-speed visual image system can not reach the same distance as a high-speed photography system.