Performance Evaluation of Multicarrier Systems Applied to Underwater Acoustic Communications

In underwater acoustic communications, orthogonal frequency-division multiplexing (OFDM) is an alternative to frequency-shift keying (FSK). The key advantage of OFDM scheme is that it provides a significant increase in transmission rate. In this paper, we simulate and compare the performance in terms of bit-error rate (BER) of the OFDM and FSK in underwater acoustic communications. As an alternative we also analyze the behavior of single-carrier frequency-division multi- plexing (SC-FDM). Lastly, to isolate the consequences of Doppler effect without masking distortions introduced by multi-path and the associated equalization procedures, their performances are also evaluated in the presence of Doppler and additive noise.