摘要
介绍了数字多媒体电视广播协议(DMB-T)中的信号帧结构,该结构引入PN码帧头用于时域同步。从理论上分析了时域同步正交频分复用多载波调制(TDS-OFDM)的参数选取策略,重点说明了子载波数量确定为3780的选择步骤。在这种信号结构下,TDS-OFDM信号的通带带宽为7.56MHz,既满足了电视带宽的要求,又满足了奈奎斯特采样定律。最后简要介绍了实现3780点快速傅立叶变换(FFT)的算法,其计算复杂度和容量复杂度都与标准的4096点FFT算法相当。
The paper presents the frame structure defined in the Terrestrial Digital Multimedia/TV Broadcasting system,which adopts PN codes as frame-preambles to achieve system synchronization in time domain.The design strategies on the operation parameters of Time Domain Synchronization-OFDM are treated,focusing on the choice of sub-carriers number(3780)in an OFDM symbol.In this system the bandwidth of the TDS-OFDM symbol is7.56MHz,conforming to the Nyquist Sample Criterion and meeting the requirement of TV broadcasting.Finally a3780-point FFT algorithm is introduced in brief,whose capacity complexity and computation complexity are close to the conventional4096-point FFT.[
出处
《电视技术》
北大核心
2003年第6期4-6,共3页
Video Engineering
基金
信息产业部电子信息产业发展基金:财建(2002)291号
