Authors : P. Sudhakar and M. Sharmila
Abstract: Mobile underwater networks with acoustic communications are faced with several unique challenges such as high transmission power utilization, large propagation delay and node mobility. The delay-aware opportunistic transmission scheduling algorithm has been mainly designed for underwater mobile sensor networks. It uses passively obtained local information to enhance the chances of concurrent transmissions while reducing collisions. Along with that, a simple performance enhancement mechanism that permits multiple outstanding packets at the sender side, enabling multiple transmission sessions has been proposed which in turn significantly improves the overall throughput. Each node learns neighboring node ’s propagation delay information and their expected transmission schedules by passively overhearing packet transmissions through the establishment of the newly developed MAC protocol called DOTS. This protocol mainly aspires to achieve better channel utilization by harnessing both temporal and spatial reuse. The simulation results exemplify that DOTS provides fair, medium access even with node mobility. Hence, this protocol also saves transmission energy by avoiding collisions while maximizing throughput. It also achieves a throughput several times higher than that of the slotted FAMA while offering related savings in energy.
P. Sudhakar and M. Sharmila, 2016. Delay Aware Opportunistic Transmission Scheduling Technique for Efficient Channel Utilization in under Water Sensor Networks. Asian Journal of Information Technology, 15: 2383-2391.