Time-domain Equalization Techniques for ADSL System

• Main Authors: Tseng Hsuan Wen, 曾玄文
• Other Authors: 魏學文
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/48802786673084425394

碩士 === 國立暨南國際大學 === 電機工程學系 === 91 === Time-domain Equalizer (TEQ) is a necessary circuit to shorten the length of channel impulse response in discrete multi-tone (DMT) digital subscriber line (DSL) systems. From the hardware implementation point of view, a simple and practical least-square (LS) channel estimation method is employed in the thesis. The simulation results show that the performance of TEQ will be seriously degraded when channel estimation error exists. To further improve the performance of TEQ, two alternative algorithms, the G1G algorithm and the simple SSNR algorithm, are presented in the thesis. Both the two proposed algorithms use three-taps filter to replace the conventional two-tap filter in DCC algorithm. Both the proposed two methods can efficiently combat the effect of the estimation error and the achievable transmission rates are satisfied. Since the proposed two methods are iterative, computation complexity can be significantly reduced. The circuit complexity of the proposed methods is much less than the conventional MSSNR and Min-ISI algorithms.