摘要： 提出一种基于中国移动多媒体广播(CMMB)系统的符号同步与时钟同步方案，其中，CMMB系统是基于正交频分复用(OFDM)实现的。为正确获得CMMB系统中OFDM符号的起始位置，并消除采样时钟偏差对系统的影响，将信标符号与循环前缀相结合，给出基于OFDM的符号同步方案，包括获取与跟踪2个阶段，以解决系统符号同步问题，同时利用OFDM符号中的离散导频对采样时钟频率偏差进行估计，取其均方误差作为验证标准，从而实现系统的时钟同步。仿真结果表明，该方案有效可行。

关键词: 中国移动多媒体广播, 正交频分复用, 符号同步, 循环前缀, 离散导频, 采样时钟同步

Abstract: In this paper, a novel symbol and clock synchronization scheme for Orthogonal Frequency Division Multiplexing(OFDM)-based China Mobile Multimedia Broadcasting(CMMB) is presented. Based on the fact that CMMB system is sensitive to the symbol and clock synchronization error, this paper gives a solution which uses the beacon of slot and Cycle Prefix(CP) to catch and tracing the window position. Clock error estimate is done with scatter pilot of OFDM symbol. The Root Mean Square Error(RMSE) of sampling time error is calculated as the standard of the scheme performance. Simulation results show the scheme is effective and feasible.

Key words: China Mobile Multimedia Broadcasting(CMMC), Orthogonal Frequency Division Multiplexing(OFDM), symbol synchronization, Cycle Prefix(CP), scatter pilot, sampling clock synchronization

中图分类号: 

• TP311.52