摘要
符号定时恢复是采用COFDM调制、解调方案的数字视频地面广播中极为关键的问题。结合实际工程应用,通过仿真分析提出了在频域符号定时前进行1/2保护间隔预校正的方法,确定了OFDM符号类型判断及预校正是进行频域符号同步的两个前提条件,提出了一种符号类型判断方法;设计出基于FPGA的相应硬件电路,经HDTV样机调试证明了其优越的性能。
Symbol timing recovery is the most crucial problem in digital video broadcasting system adopting COFDM modulation scheme. For the engineering application, this paper proposes a new method of the 1/2 guard interval prerectification before symbol synchronization in frequency domain through analysis and computer simulation. Also, it points out that the judgement of OFDM symbol type and prerectification are the two prerequisites for accurate symbol timing recovery, and then presents a method of symbol type judgement as well. The designed correspondent FPGA hardware circuit proves its rightness and excellent performance through testing process in the functional HDTV.
出处
《南京邮电学院学报（自然科学版）》
2002年第4期16-20,共5页
Journal of Nanjing University of Posts and Telecommunications
基金
国家重点科研基金(数字视频关键技术)资助项目
关键词
OFDM符号
高清晰度电视
编码正交频分复用
保护间隔预校正
符号类型判断
现场可编程门阵列
High Definition TV
Coded orthogonal frequency division multiplexing
Guard Interval Pre-Rectification
Judgement of symbol type
Field programmable gate array
