Selected mapping and partial transmit sequence schemes to reduce PAPR in OFDM systems
Orthogonal Frequency Division Multiplexing (OFDM) has been currently under intense research for broadband wireless transmission due to its robustness against multi-path fading. However, OFDM signals are characterized by large peak-to-average power ratios (PAPR), which can reduce the system efficiency. To overcome this problem, in this paper, based on the definition of the PAPR in OFDM systems, we will mainly investigate the PAPR reduction performance with two different PAPR reduction methods: the selective mapping (SLM) and partial transmit sequence (PTS). A comprehensive analysis and comparison are conducted in terms of all possible influencing factors and PAPR reduction performance, respectively. Some research findings are obtained based on the simulation results. The results verify that PTS method provides a better PAPR reduction performance compared to SLM method and the probability of high PAPR with increasing the number of sub-blocks in PTS technique decreases obviously, compared to the original OFDM signal. In addition, SLM algorithm is more suitable if the system can tolerate more redundant information; otherwise, PTS algorithm is more acceptable when complexity becomes the first considering factor.