Performance of scaled SLM for PAPR reduction of OFDM signal in PLC channels

Abstract

Orthogonal frequency division multiplexing (OFDM) modulation using orthogonal subcarriers reduces the delay spread by increasing robustness to multipath fading and can use overlapped bandwidth due to orthogonality on frequency domain. Thus, OFDM has been adopted for high speed data transmission of multimedia traffic such as HomePlug A/V and Mobile WiMax. However, OFDM also has a drawback of a high PAPR (peak-to-average-power-ratio). This high PAPR takes place due to parallel processing of a number of data at once using a fast Fourier transform (FFT) processor. Due to this high PAPR amplifier usually does not act in dynamic range. In this paper, we propose an algorithm that can reduce PAPR using selective mapping (SLM) in power line communication (PLC) channel. In order to utilize SLM technique, side information needs to be transmitted for demodulation while degrading transmission efficiency. We propose and analyze scaled SLM technique which removes necessity of the side information.