在電力線通訊中, 主要使得正交分頻多工系統效能降低的因素為脈衝雜訊。為了克服脈衝雜訊的障礙, 裁切法已被提出並證實為有效的方法。有別於傳統在頻域上的最大似然解碼方法, 本論文提出在時域上做最大似然解碼估測。在使用線性區塊碼和正交分頻多工的系統下,我們利用電腦模擬比較所提出的方法和文獻中的裁切法。模擬結果顯示, 本論文所提出的方法優於文獻中的裁切法。

The major degradation of the performance by OFDM technique in a power line communication system comes from impulse noises. In order to overcome the effect of impulse noises, a clipping method has been proposed and verified as an efficient technique. This paper, however, proposes a method by maximum likelihood decoding in the time domain instead of frequency domain in the traditional OFDM system. This paper then conducts computer simulation to compare the proposed scheme with the clipping method under the system, in which the linear block code and OFDM systems are utilized. The simulation result shows that the proposed method outperforms the clipping method proposed in the literature.

摘要 i
Abstract ii
1 序論 1
1.1 研究動機 1
1.2 研究方法 2
1.3 研究貢獻 2
1.4 論文架構 2
2 系統模型 3
2.1 正交分頻多工簡介 3
2.2 電力線通訊雜訊介紹 6
2.2.1 連續型雜訊 7
2.2.2 脈衝雜訊 7
2.2.3 數學模型 7
2.3 系統架構 8
2.4 脈衝雜訊模型 9
3 裁切法與最大似然解碼介紹 10
3.1 裁切法 10
3.2 最大似然解碼 12
4 裁切法與最大似然解碼應用 14
4.1 裁切法應用 15
4.2 最大似然解碼 16
5 模擬結果和分析 18
5.1 裁切法的模擬結果 18
5.2 最大似然解碼方法模擬結果 22
6 結論 26
參考文獻 27

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