Several Designs for Reduced-Power Coded Tomlinson Precoding Systems

• Main Authors: Wen-Feng Tsai, 蔡文丰
• Other Authors: 林茂昭
• Format: Others
• Language: en_US
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/09370813896448838777

碩士 === 國立臺灣大學 === 電信工程學研究所 === 92 === Tomlinson-Harashima precoding is the equalizer technique for eliminating intersymbol interference with the channel response known by the transmitter. By placing equalizer at the transmitter side of the communication system, the intersymbol interference can be completely eliminated without noise enhancement. However, the Tomlinson- Harashima precoding has two defects. The First is called data flipping, which occurs when the amplitude of the received signal is large and the modulo 2M operation causes the sign change. The Second, due to the feedback design of Tomlinson-Harashima precoding, the output amplitude become uniformly distribution, so that transmitted power is increased. In this thesis, we will focus on the second problem. We consider the usage of several methods to lower the average output power. The considered methods include trellis shaping proposed by Forney, a method of using maximum-length sequence, and Multi-Interleaver method. We will compare above methods at last.