数字电视条件接收原理探讨

Discussion on the Theory of Conditional Access System for Digital TV

主要分析了条件接收系统前端和接收端的工作原理,以及条件接收系统(CAS)、用户管理系统(SMS)、授权控制信息(ECM)、授权管理信息(EMM)和通用加扰算法等在DVB同密或多密系统中的协同工作,并重点介绍了授权控制信息(ECM)、授权管理信息(EMM)之间的相互关系。

This paper introduces the theory on head-end and receiver of the conditional access system, which is the synchronous working among all of the modules including conditional access systems （CASs） , subscriber management system （ SMS）, entitlement control message （ ECM）, entitlement management message （ EMM ） and DVB - CSA in a DVB simul-crypt and multi-crypt system. As an emphasis, the paper describes the correlation between ECM and EMM module.