Underwater Acoustic Communication Using Doppler-Resilient Orthogonal Signal Division Multiplexing with Time Diversity

Recent advancements in underwater technology have made cooperative exploration, an efficient underwater exploration technique, possible. This technique networks mobile and fixed platforms, sensors and systems, and makes it possible to accomplish underwater tasks efficiently by integrated operations over a wide area and balancing exploration and exploitation. As a networking technique, underwater acoustic (UWA) communication is a technology of choice today, since it can enables mobility and flexibility in cooperative exploration systems. However, UWA communication still has several design challenges which need to be carefully addressed. To provide a reliable UWA modem suitable for cooperative exploration, in this study we designed a Doppler-resilient orthogonal signal division multiplexing with time diversity (D-OSDM-TD) and evaluated its performance in simulations and experiments. We evaluated the D-OSDM-TD in simulations and experiments and found that the D-OSDM-TD achieved a far better bit-error-rate performance in UWA channels with delay and Doppler spreads using low signal power and without using a receiver array. We expect that D-OSDM-TD can become a viable alternative offering highly reliable communication for underwater operations, and we believe it is suitable for underwater cooperative operations.