Application of PSO Optimized Companding in Peak Average To Power Ratio(PAPR) Reduction In Orthogonal Frequency Division Multiplexing(OFDM)

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. The main drawback of Orthogonal Frequency Division Multiplexing(OFDM) systems is the high peak-to average power ratio (PAPR),which significantly reduces the efficiency of the transmit high power amplifier (HPA). Several methods have been proposed in the literature to reduce the peak power of OFDM signals and substantial gains were reported. This dissertation is focused on analyzing PAPR reduction by undertaking various methods to reduce the PAPR in the system like Selective mapping (SLM), Companding-SLM and Particle Swarm Optimized-Companding (PSOCompanding). The technique PSO-Companding has been proposed which reduces the PAPR in the wireless system.Simulation result shows that the proposed PSO optimized companding method outperforms than the existing methods of PAPR reduction companding and SLM. Keywords—OFDM, peak-to-average power ratio (PAPR), high power amplifier (HPA), SLM,PSO