基于DTMB标准多载波模式的同步系统设计  

Design of synchronization system based on standard multi-carrier mode of DTMB

作　　者：肖辉[1] 郭里婷[1] 高正含[1] 吴林煌[1] 

机构地区：[1]福州大学物理与信息工程学院,福州350108

出　　处：《电子测量与仪器学报》2013年第9期889-896,共8页Journal of Electronic Measurement and Instrumentation

基　　金：福州大学科技发展基金(2011-XQ-29);福州大学育苗基金(600635)资助项目

摘　　要：针对地面数字电视国家标准(DTMB)的多载波模式,设计了一个同步系统。提出一种实现DTMB多载波系统同步的流程。将同步系统划分为捕获和跟踪两种状态。通过判断定时误差提取器输出的互相关序列的相关峰的尖锐程度及位置是否发现改变,实现捕获和跟踪状态之间的切换。针对系统中可能出现的突发频偏,提出了相应的处理方法。仿真表明:在信噪比为20 dB、AWGN和多径信道下,当频偏跟踪环路锁定后,残余频偏约为1 Hz并且在AWGN信道下的帧体数据的星座图相比同步前有明显的改善;当突发状况导致系统不再同步时,系统能够自动恢复到同步状态。仿真结果验证了本设计方案的可行性。A synchronization system is designed for multi-carrier mode of DTMB. The synchronous procedure is presented for DTMB multi-carrier system. Synchronization system is divided into acquisition state and tracking state. By judging the sharp degree and correlation peak position of the cross-correlatiota sequence from timing error extractor, it can realize the switch of acquisition state and tracking state. The simulation results show that under sig- nal-to-noise ratio 20 dB, AWGN and muhipath channel, when the frequency offset tracking loop lock, the residual frequency offset is about 1 Hz, and constellation of frame body data is significantly improved. When unexpected situ- ations cause the system is no longer synchronization, the system can automatically restore to synchronization status. The simulation results demonstrate the feasibility of the design.

关 键 词：地面数字电视国家标准 同步系统 定时误差 相关峰 残余频偏 

分 类 号：TN945[电子电信—信号与信息处理]