A REVIEW ON LOCALIZATION ALGORITHMS IN UNDERWATER SENSOR NETWORKS

This review paper provides a comprehensive examination of localization algorithms in underwater sensor networks (USNs), addressing the unique challenges posed by the aquatic environment, such as severe signal attenuation, multipath propagation, node mobility due to water currents, and significant energy constraints. It categorizes the localization algorithms into time-of-arrival (TOA), time-difference-of-arrival (TDOA), received signal strength indicator (RSSI), angle-of-arrival (AOA), and hybrid and collaborative approaches, highlighting their operational mechanisms, advantages, and limitations. Furthermore, the paper discusses the current trends and future directions in USN localization, including the integration of machine learning techniques and the potential for enhancing localization accuracy through the use of auxiliary information like ocean current models. Through an analysis of existing literature and a discussion on the environmental challenges and technical limitations of underwater communication technologies, this paper aims to provide insights into the advancements and remaining hurdles in the field of USN localization, contributing to a deeper understanding of its critical role in enhancing the capabilities and applications of underwater sensor networks.