Impact of Acoustic Propagation Models on Depth-Based Routing Techniques in Underwater Wireless Sensor Networks

Depth-based routing protocols play a key role in assuming realistic approach by considering the continuous node movement in aqueous environment. The performance attributes of depth-based routing protocols highly depend upon the depth information of sensor nodes. Although this information is not prioritized by all acoustic models to estimate channel conditions, however, some notable models consider depth information of nodes. In this paper, we discuss the analysis of two major acoustic propagation models of Thorp and Monterey-Miami Parabolic Equation (MMPE) in predicting transmission losses with four notable depth-based routing techniques of Depth-Based Routing (DBR), Energy Efficient Depth-Based Routing (EEDBR), Adaptive Mobility of Courier nodes in Threshold-optimized Dbr (AMCTD) and Improved Adaptive Mobility of Courier nodes in Threshold-optimized Dbr (IAMCTD). We highlight the complexity and accuracy of these models in estimating the performance of higher layer protocols. Simulations show that physical layer parameters highly affect the performance of routing layer protocols as predicted by later propagation models. Results also prove that distant transmissions cause high propagation losses which are overcome by latest depth-based routing protocols. These protocols analyze the results of MMPE model to enhance upper channel limits and network lifetime.