PAPR reduction using SC-FDMA in Underwater acoustic channel

Abstract

Underwater acoustic sensor networks (UWASN) have been developing and attracting growing interests recently. However, underwater acoustic (UWA) communications undergo multipath, delay and limited bandwidth. Orthogonal frequency division multiplexing (OFDM) is suitable for UWA communications because of their immunity against frequency selective fading. It can mitigate inter-symbol interference (ISI). But, OFDM is highly sensitive to the frequency offset, and it also has large peak-to-average power ratio (PAPR). This new modified technique of OFDM is called Single carrier frequency division multiple access (SC-FDMA). SC-FDMA has only single carrier, so it has reduced PAPR. Pulse shaping technique using raised cosine filter reduces PAPR. Based on pulse shaping, the Nyquist filter is used to reduce the PAPR. The complexity and design of this technique is simpler. The bandwidth efficiency is not affected. Also, there is less of In Band as well as Out band distortion. SC-FDMA is applied to UWA channels and MATLAB is used for simulation. For both OFDM and SC-FDMA, Bit error rate (BER) and PAPR will be calculated. The result should show that the less bit error rate than the BER of 10-3 which is the average can be achieved using SC-FDMA in UWA.