数字电视的条件接收系统原理与应用

Principle and Application of Digital TV Conditional Access

数字电视指将传统的模拟信号转化为数字进行处理、传输和接收的系统。数字电视的条件接收系统运用各种数字技术通过对节目的加扰处理，使只有授权用户才能收看被加扰节目，从而保障运营商的利益，保证数字电视发展。 本文主要闻述当前前数字电视使用的条件接收系统的基本原理，以及实际中应用两种条件接收方式的设计和实现，并比较两种方式的优势和不足。最后介绍当前国内数字电视发展的现状。

The digital TV is such a system to convert the signal from analog into digital for further processing, transmit and reception. The conditional access system will use a lot of digital technology to disturb TV programs only for the reception of described programs to be received by authorized users. In this way the digital TV operator interests can be secured.