European Journal of Molecular & Clinical Medicine ISSN 2515-8260 Volume 07, Issue 03, 2020 745 Green-Centric Communication Void Avoidance for Underwater Wireless Sensor Networks Umar Sani 1 , Mohd Murtadha Mohamad 2 1 School of Computing, Faculty of Engineering University Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia 2 Department of Computer Science, Faculty of Science, Sokoto State University, PMB 2134, Sokoto, Nigeria email: murtadha@utm.my 2 Abstract: Recently, there is rapid interest in the study of Underwater Wireless Sensor Network (UWSN), which is due to it verse applications such as pollution monitoring, seismic monitoring, equipment monitoring, disaster prevention, tactical surveillance, oceanography data gathering, and assisted navigation. Meanwhile, the realization of these applications is confronted with some underwater limitations namely, acoustic channel constraint, limited bandwidth, and water pressure. Several routing algorithms have been developed to achieve efficient data gathering. However, these algorithms are challenged with communication void problem. The communication void problem leads to packet drop/error and high energy consumption in the course of data packet forwarding. Therefore, in this paper, an improved communication void avoidance mechanism for UWSN has been proposed for handling void hole during data packet forwarding considering dislodgment of sensor nodes. The performance of the proposed mechanism has been evaluated against the adapted adjustment mechanism to confirm its benefit based on different data packet forwarding and energy efficiency metrics. Keywords : Void hole, Communication void, Underwater wireless sensor network, Data forwarding, Energy efficiency 1. INTRODUCTION The universe consists of seventy percent water of which ninety percent is of oceans. Thus, humans on earth cannot neglect the large quantity of water (Akyildiz et al., 2005). This has led to the exploration of water medium for gathering and sharing valuable information. The information dissemination employing UWSNs is considered as one of the promising technologies for underwater applications. The applications including pollution monitoring to the determination of natural disasters, oil exploration to aquaculture, submarine function, and climate monitoring (Vasilescu et al., 2005; Partan et al., 2007; Heidemann et al., 2012). In the underwater environment, radiofrequency waves cannot be used as a reliable communication medium. This is because radio frequency equipment depletes more energy by raising the attenuation factor. Generally, water becomes a conductor for radiofrequency waves when the