電力線通訊系統可直接銜接既有的配電網路，具有低成本的特色，在智慧電網與家庭網路中扮演重要角色。但此系統遭受多路徑衰減和隨機脈衝雜訊導致系統效能不佳，因此探討與改善上述影響傷害為電力線通訊系統的主要議題。
依據寬頻電力線G.hn (Gigabit Home Networking)標準規格，此標準使用的錯誤更正編解碼技術為低密度奇偶檢查碼(Low Density Parity Check code)。本論文將模擬分析偵測隨機脈衝雜訊的不同方法，同時整合(理想)通道等化器以降低多路徑衰減的影響；針對有寬度的脈衝雜訊，會搭配交錯器使系統性能提升。然而改錯碼一般是考量在背景雜訊功率固定的通道下，若通道存在額外的雜訊(如脈衝雜訊)影響，則會降低解碼能力。因此將各處理造成的功率變化轉換為有意義的資訊，並引用於LDPC軟式解碼器所需要的對數似然比(Log-Likelihood Ratio, LLR)計算中，藉以提升系統效能。

Power line communication (PLC) system can exchange information over the existing electrical grid without much extra implementation cost. Such system will play an important role in the future Smart Grid. The multipath fading and random impulse noise (IN) will lead to the poor performance. Therefore, the development of novel technologies to explore the impact of these is the main research topic for the PLC system.
The study of this thesis is based on the G.hn (Gigabit Home Networking) standard for broadband PLC systems. This standard adopts the low-density-parity-check (LDPC) for error-correction. The thesis analyzes different detection schemes for the random impulse noise by simulations. Also, the system combines the (ideal) channel equalizer to combat multipath channels. Moreover, for the memory(busty) impulse noise, the interleaver is also adopted. Generally, the use of error-correcting code is under the assumption of a fixed background noise channel. If there is additional variant noise, the decoding ability will be reduced. Therefore, we can modify the log-likelihood ratio (LLR) calculation of the LDPC decoder with the information of noise-power change due to the process of IN reduction and equalizer, to improve the system performance.

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