说明：  伴随着手机电视成为3G大家关注的焦点，CMMB技术倍受关注，本文当为广电总局的内部培训文档，详细介绍了CMMB技术框架
(Along with 3G mobile TV to become the focus of everyone s attention, CMMB technology has drawn greater attention, this article as SARFT s internal training document, detailing technical framework CMMB)