A Transmission Scheme for Continuous ARQ Protocols over Underwater Acoustic Channels

Due to the half-duplex property of the underwater acoustic channels, the classic stop-and-wait ARQ (SW-ARQ) and its variants are generally thought to be the only class of ARQ protocols that can be applied in underwater. When combined with the large propagation delay property of the underwater acoustic channels, the use of SW-ARQ and its variants makes the throughput performance of underwater acoustic communication systems very inefficient. In this paper, we propose a transmission scheme that takes advantage of the long propagation delay in underwater to enable the use of continuous ARQ protocols over underwater acoustic channels. Simulation results show that our proposed transmission scheme allows much higher throughput to be achieved than both the classic SW-ARQ and its variants, even when simple continuous ARQ protocols are used.