Orthogonal Frequency Division Multiplexing (OFDM) suffers from a high Peak-to-Average Power Ratio (PAPR). Designing a High Power Amplifier (HPA) with high PAPR is not a wise technique as it roots the amplifier to operate in a non-linear region which is intricate. Linearity and power efficiency are important constraints of HPA which cannot be achieved at the same time. Therefore, perfect linearity is observed when efficiency is low or vice versa and efficiency can be improved by decreasing the PAPR. In this paper, the PAPR is mitigated by using Partial Transmit Sequence (PTS), Selected Mapping (SLM), Hybrid and proposed methods. Analysis of OFDM with high PAPR passing through different HPA models is evaluated in terms of Power Spectral Density (PSD), gain and efficiency for all PAPR reduction methods considered in this work. The results are encouraging by using hybrid PAPR reduction method, HPAs can be operated in a linear region to provide higher efficiency compared to non-hybrid PAPR reduction methods. Hence, hybrid PAPR reduction methods can be used even in future wireless communications systems including 5G and beyond. INDEX TERMS Companding, high power amplifier models, orthogonal frequency division multiplexing, peak to average power ratio, partial transmit sequence, selected mapping.

No abstract

No abstract

No abstract

A novel combined approach of SLM (Selective Mapping), PTS (Partial Transmit Sequence) and DSI (Dummy Signal Insertion) is proposed to diminish PAPR (Peak to Average Power Ratio) and OBI (Out of Band Interference) in OFDM (Orthogonal Frequency Division Modulation) systems. The efficiency of OFDM decreases while the cost of installing HPA (High Power Amplifier) increases when the PAPR factor is high. A lot of research has been done to minimize this factor. The proposed method reduces the computational complexity by minimizing the number of IFFT (Inverse Fast Fourier Transform) operation to a half and the results show an effective decrement of PAPR by 0.6 ~ 1.4 dB. It also proved from the simulation results that it has 3.2 ~ 4 dB lower OBI when compared against the conventional and existing methods.