摘要
针对目前基于 VSB技术的高清晰度电视 (HDTV)传输系统对付严重畸变信道的不足之处 ,给出一种新型的均衡器 .该均衡器采用间接均衡的方式 ,首先进行快速信道估计 ,得到初始化系数 ,以打开眼图 ,然后以此为基础进行自适应均衡 .均衡器结构采用判决反馈均衡器 (DFE)的部分 IIR提前结构 ,提高系数收敛速度 .仿真结果表明 ,该均衡器可以对付在巴西测试中 ,传统 VSB系统无法对付的恶劣信道条件 .
A new type equalizer for HDTV transmission system based on VSB technology to cope with severely distorted channel situation is proposed. The ordinary equalizer, decision feedback (DFE) structure and recursive equalizing algorithm is used. Because of the multipath spreading in FIR, the ordinary DFE has a slow convergence of the weight coefficient in the former condition, and the recursive algorithm cannot work with the signal submerged in interference. The new equalizer adopts indirect equalizing style and new algorithm is used for fast estimation of the channel impulse responses used as initial weight coefficients of the adaptive equalizer. A modified DFE structure of decision feedback equalizer is proposed to get faster convergence of weight coefficients. The simulation results show that the new style equalizer can work well in severely distorted propagation channel while the ordinary equalizer cannot, and it was tested in Brazil.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2002年第3期298-302,共5页
Journal of Zhejiang University：Engineering Science
基金
"九五"攻关资助项目 (96-B0 6-0 1-0 5 )
关键词
高清晰度电视
传输系统
均衡器
Communication channels (information theory)
Computer simulation
Decision feedback equalizers
High definition television
Impulse response
Multipath propagation
Television transmission
