A novel combined SLM-PTS technique based on Genetic Algorithms for PAPR reduction in OFDM systems

摘要

0FDM has today becoming the modulation of choice for most modern broadband communication systems in use, either wireline or wireless. The main reasons is that OFDM provides the best usage of the available frequency band which maximizes the spectral efficiency and also its robustness to the multipath fading channel. However, OFDM has a major drawback of having a large Peak-to-Average Power Ratio (PAPR). The larger peak-to-average power ratio (PAPR) leads to frequency spread spectrum along with the in-band distortion, this is because of the non linearity present in the high power amplifiers.Most of the promising PAPR reduction methods are the Selective Mapping method (SLM) and Partial Transmit Sequence (PTS) which can achieve better PAPR performance without signal distortion. In this paper, a novel efficient PAPR reduction method using combined SLM and PTS techniques based on the Genetic Algorithms (GA) is proposed. GA is a kind of evolutionary computing algorithms that is applied to the combined SLM-PTS technique to get optimal phase rotation factors. The simulation results show that the proposed technique performance is better than the conventional SLM, conventional PTS and combined SLM-PTS techniques and also reduces the computational burden of the combined SLM-PTS scheme.