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Accuracy of RF based underwater intruder localizations using sensor networks with shadow fading

For observations and surveillance in oceanic environment, acoustic based underwater wireless sensor networks (UWSNs), the widely used medium, is highly challenged while the demand for underwater operations with fast response and higher data rates is on the rise. In such scenarios, radio frequency (RF) based underwater networks exhibit great potentials for supporting these requirements. From that fact, this work presents and examines the accuracy of RF UWSN based schemes for determining the presence and position of underwater intruders under shadow fading scenario. The considered UWSN topology consist of cluster heads (CHs) and sensor nodes (SNs) to detect intruder inside the network and transmit the real-time position of the unwelcomed object to a land-based base station (BS) via a sink at water surface. All data from SNs to BSs is passed using RF wave based communications. For approximating the object's position, information of received RF signal strength, and the positions of SNs and CHs are utilized. Substantial simulations are followed through for evaluating the proposed networks' performance in an oceanic environment with shadow fading. Localization accuracy of the networks is carefully examined in terms of distance approximation errors and the probability of missing detection. Effects of various network settings on the system performance are also critically scrutinized.