同步多载波扩频地面数字电视传输协议

Synchronized multi-carrier CDMA terrestrial television transmission protocol

提出同步多载波扩频(SMCC)技术,其中用多载波技术OFDM克服多径效应和建立单频网体制(分布化),采用时-频并行扩频技术(CDMA)带来的快速OFDM符号同步克服在遮蔽间穿行接收的信号重入/再同步困难,采用周期连续导频技术解决高速移动时的多普勒频移跟踪问题和运动衰落(面向移动接收),采用系统传输流的定秒精确同步技术解决在建立蜂窝单频网(CellularSFN)传输体制(基站化)的困难,用以解决城市楼群遮蔽的覆盖问题,并为数据回传(双向化)所需的同步、定时、定位提供技术手段。

The'Synchronized Multi-Carrier CDMA'technique advanced in this article,adopts the Multi-Carrier technique(COFDM)to withstand the multi-path effect and to establish the Single Frequency Network(SFN)System(Distributed TV).With the Fast-Synchronization of the OFDM Symbols by means of the time-domain parallel Spread-fre-quency technique(CDMA)to overcome the difficulties of the signal re-acquiring and re-synchronization while moving a-mong the building shadows.With the periodically arranging continual Pilot sub-carriers to solve the problem of Doppler tracking and the motion(Time /Space)Fading while speedy moving.The'per second precise'synchronization technique of the system transmission stream is deployed to settle the complexity of establishing the cellular SFN transmission system(TV Base-Stations)and the Shadowing problem.And it is also provided the technical means for the Network synchro-nization,timing and positioning,which are necessary in the future data return path(bi -directional TV).[