Improved MFO Algorithm Based PTS Scheme in OFDM Systems For PAPR Reduction

Abstract

Orthogonal frequency division multiplexing (OFDM) is a multicarrier modulation method employed in wireless communications. To achieve High-speed transmission over fading channels with frequency selection, the OFDM approach is frequently used. The peak-to-average power ratio is a measure of how dynamically the OFDM signals vary in amplitude over time because of their multicarrier nature (PAPR). When PAPR is high, the OFDM signal will clip when it is amplified by a non-linear high-power amplifier (HPA), which will reduce performance. It also increases the bit error rate (BER) and power spectral density (PSD). It was suggested that partial transmit sequence (PTS) might enhance OFDM systems PAPR performance. But by adding it, the system’s computational complexity is significantly increased as in this process the best solution has to be selected among number of solutions which is complex and time consuming. So, we need an optimization algorithm to select the best solution. Hence, we proposed a PTS PAPR reduction scheme optimized by moth flame optimization (MFO) algorithm. Previously we had to manually choose the samples, but now by using MFO algorithm the system automatically chooses the samples, which saves time and reduces computational complexity of PTS scheme. This technique provides us with samples that have lower PAPR levels in OFDM systems. So, this proposed method gives us the signals with low PAPR, and reduces the BER and PSD.