Performance Evaluation of ZP-OFDM Scheme in Underwater Multipath Channel

One of the major problems while dealing with underwater acoustic communication (UWAC) is the occurrence of unwanted multipath having long delay spreads. Higher probability of reflections (from wavy sea surface, uneven sea bottom, other obstacles, etc.) and refraction of sound are the main causes of these grievous multipath signals. Multipath effects further offer severe degradation in the packet (s) and mutilation of entire signal in terms of inter-symbolic interference (ISI) is occurred. During last decade, multicarrier modulation in terms of OFDM was considered as one of the viable solutions to mitigate the multipath effect and provide high-rate communication. In this article, we are performing the practical evaluation of Zero-Padded Orthogonal Frequency Division Multiplexing (ZP-OFDM) based communication system. The data using various packet structures are used to demonstrate the effectiveness of ZP-OFDM scheme in the flat multipath channel of the water pool of acoustic lab, Harbin Engineering University. Satisfactory performance results are obtained even within high noisy environment. These results suggest that ZP-OFDM is a viable choice for high-rate communications over multipath induced underwater channels.