数字信号相对模拟视频信号的电平设置  

Recommended Levels of Digital Channels Relative to Analog Channels

作　　者：张放 

机构地区：[1]有线电视技术专业委员会,上海201103

出　　处：《电视技术》2014年第8期51-55,共5页Video Engineering

摘　　要：数字QAM频道不仅用于VOD点播,也用于直播电视,已在有线电视系统中大量部署,并且与模拟频道同时传输。如何正确设置二者的电平,关系到系统的性能指标和长期运行的稳定性。先给出了视频信号的概念和定义,然后详细描述了模拟与数字信号合成总功率的计算方法,最后介绍了数字平移后电平的调试方法。Digital QAM channels have been deployed more and more and also co-work with analog channels in cable TV systems. It is not only for VOD but also for TV broadcasting. It is important for system performance and long-term running stability that how to have a RF level setup correctly. The definitions of video signals is indicated first, and then the calculating steps in detail about total power level of analog and digital channels are described. Finally some adjustment methods of RF total power levels after digital TV transfer are introduced.

关 键 词：有线电视 QAM测量 电平设置 

分 类 号：TN949[电子电信—信号与信息处理]