Shallow-Water Experimental Results of Differential OFDM for Underwater Acoustic Communications in the Presence of Severe Double Selectivity

This paper confirms that differential orthogonal frequency division multiplexing (OFDM) offers excellent performance for underwater acoustic communications (UWACs) in the presence of severe double selectivity. In this paper, geometrical conditions leading to severe double selectivity in shallow-water experiments are derived. Furthermore, experimental results obtained under the shallow-water conditions are presented. These results demonstrate that the proposed differential OFDM employing multiple differential detection with channel prediction provides superior performance in the presence of severe double selectivity.