APPLYING STOCHASTIC NETWORK CALCULUS FOR PERFORMANCE EVALUATION OF HARQ PROTOCOLS IN UNDERWATER ACOUSTIC WIRELESS SENSOR NETWORKS

An Underwater Acoustic Wireless sensor networks are becoming increasingly important in applications like environmental monitoring, military surveillance, and geological data collection. However, these networks are forced to face significant difficulties because of the harsh environment in underwater, including high latency, minimal bandwidth, and excess error rates. Traditional Automatic Repeat Request (ARQ) protocols often rely only on error detection and retransmission and thus are insufficient to solve these problems. Hybrid Automatic Repeat Request (HARQ) protocols offer a promising solution to these challenges by integrating error correction and retransmission strategies. Hybrid Automatic Repeat request (HARQ) protocols, which combine error correction and retransmission strategies, offer a promising solution. This article explores the application of HARQ protocols in UAWSNs and evaluates their performance using stochastic network calculus. The study focuses on three main types of HARQ protocols: Type I, Type II and Type III. Stochastic network calculus, a mathematical framework for analysing network performance under uncertainty, is used to model and evaluate these protocols. Key performance metrics such as delay, throughput, and packet delivery ratio are analysed. Simulation results show that Type II HARQ, which combines new and previously received packets for enhanced error correction, provides the best performance in terms of reliability and efficiency. The findings demonstrate that HARQ protocols, especially Typey II, can significantly improve data transmission reliability in UAWSNs, making them a viable option for overcoming the challenges of underwater communication. Future research directions include exploring adaptive HARQ mechanisms and integrating HARQ with other error control techniques for further performance enhancement.