一种新的地面数字多媒体/电视广播传输系统

A new terrestrial digital multimedia /television broadcasting(DMB-T)transmission system

针对传输信道线性时变的宽带传输信道特性,设计了一种时域同步正交频分复用(简称TDS-OFDM)的多载波调制方式。这种调制方式既适用于具有多径干扰和多普勒频移的地面数字电视广播传输信道,也适用于其它宽带数字传输系统。为了进一步提高传输效率,提出的地面数字多媒体/电视广播DMB-T传输系统还采用了最新的纠错编码和交织编码技术,在额定的8MHz带宽中,净载数据传输率可达32.511Mbps。

The paper presents a new terrestrial digital multimedia/TV broadcasting transmission system:(DMB-T)DMB-T is designed for the transmission channel with both time selective and frequency selective characteristics.A novel multi-carrier modulation scheme called TDS-OFDM(Time Domain Synchronous Orthogonal Frequency Division Multiplex)is introduced in the DMB-T.TDS-OFDM can be viewed as a zero-padded OFDM signal time division multiplexed by a coded PN sequences.The coded PN sequences can be used to fulfill all the functions,such as carrier recovery,timing recovery,frame synchronization,frame addressing,time domain equalization,and channel estimation before OFDM de-modulation.Also,a new FEC(Forward Error Control)scheme call multi-layer block product code is applied in the DMB-T to make the high performance Turbo decoding algorithm feasible for the64QAM constellation.[