在正交分頻多工(Orthogonal frequency-division multiplexing，OFDM)系統中，高峰均值功率比(Peak-to-Average Power Ratio，PAPR)是現實中廣泛討論的議題，因為高峰均值功率比會使類比/數位轉化器(ADC)的轉換效率下降，以及提高非線性功率放大器的成本。在許多文獻中都有提到降低峰均值功率比的方法，在這些方法中，裁剪(Clipping)是最直觀也是複雜度最低的有效方法。
在一些智慧型建設中會使用電力線通訊(Powerline Communication，PLC)達到節能的目的，而電力線通訊傳輸以正交分頻多工調變為基本架構。訊號利用電力線傳輸也會碰到一些問題，例如因開關轉換引起的脈衝雜訊(Impulse noise)，會成為電力線傳輸中影響訊號品質的關鍵。為了達到降低脈衝雜訊的影響及低複雜的目的，我們在接收器之前端利用限幅器(Limiter)降低干擾，使用限幅器時不考慮脈衝雜訊功率之相關資訊，此外在系統中利用通道編碼搭配限幅器對抗脈衝雜訊。在考慮前段所提的傳送端進行裁剪及功率放大器的情況下，並配合一些環境參數的變更，如：裁剪比(Clipping ratio，CR)及輸入回饋(Input back-off，IBO)，找到合適參數區間以達到所需效果。

High Peak-to-Average Power Ratio (PAPR) has been widely known as a practical issue when implementing Orthogonal Frequency Division Multiplexing (OFDM) based communication systems. Indeed, high PAPR takes a heavy toll on the efficiency of Analog-to-Digital Converter (ADC) as well as the cost of nonlinear power amplifier. There are quite a number of approaches to reducing the PAPR in the existing literature. Among them, the clipper, though conceptually straightforward, is also praised for its simplicity in terms of implementation.
OFDM-based Powerline Communication (PLC) systems are poised to play a key role on energy saving as the deployment with regard to infrastructure is primarily ready for use. Nevertheless, some hurdles such as, for instance, impulse arising from appliances equipped with a switching regulator, pose a great challenge to the signal quality of service assured by the PLC. Considering an effective but low-complexity scheme to combat the impulse, we place a limiter in the very front end of the receiver but forgo the knowledge of the power ratio between the impulse and the background noise. In addition, channel coding in couple with the limiter has been investigated for OFDM systems undergoing the impulse. We extend the scenario by taking into account the above-mentioned clipper and indispensable power amplifier at the transmitter side and by accommodating the clipping noise to the receiver. Simulations are carried out with a number of parameters such as, for example, clipping ratio and IBO varied to demonstrate that with regard to which ranges of parameters the effectiveness of the proposed scheme can be asserted.

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