改进的DMT-ADSL系统时域均衡器

在DMT-ADSL(Discrete MultiTone-Asymm etric Digital Subscriber Line)系统中,传统时域均衡器算法的改进对系统性能改善不大,为此,通过改进传统时域均衡器的结构,对一种新的双路结构TEQ(Time-domain E-qualizer)进行讨论。这种新的结构在传统单路TEQ的基础上加入另一个TEQ,根据预设规则从两个路径中选择一个作为输出。该方法有利于最优化每个子信道上的比特数量。仿真比较了各种不同算法情况下双路时域均衡器的性能。结果表明,比特速率最高为MMSE(Minimum Mean-Square Error) MBR(Maximum Bit Rate)组合的双路TEQ,达到37.76%;最低为MSSNR(Maximum Shortening Signal-to-Noise Ration) Min-ISI(Mini-mum Intersymbol Interference)组合的双路TEQ,达到0.91%。

Improved TEQ for DMT-ADSL Systems

In the system of DMT-ADSL(Discrete MultiTone-Asymmetric Digital Subscriber Line),considering the improvement of improving on the traditional TEQ(Time-domain Equalizer) arithmetic is not obvious,a new Dual-Path TEQ structure by improving the traditional TEQ structure is studied.This structure adds a second TEQ to the originally single-path TEQ,and we choose output from one of the two paths according to a preset rule.This method works well in optimizing the number of bits supported on each subchannel.We compared the performances in different dual-path TEQ used different arithmetic,the results indicate: The MMSE+MBR Dual-Path TEQ achieved highest Achievable Bit Rate(ABR),reached 37.76%;The MSSNR+Min-ISI Dual-Path TEQ achieved lowest ABR,reached 0.91%.