Implementation of depth‐based routing and its enhancement in AquaSim–Next Generation for underwater wireless sensor networks

Abstract

Summary In the last decade, underwater wireless sensor networks have been widely studied because of their peculiar aspects that distinguish them from common terrestrial wireless networks. Their applications range from environmental monitoring to military defense. The definition of efficient routing protocols in underwater sensor networks is a challenging topic of research because of the intrinsic characteristics of these networks, such as the need of handling the node mobility and the difficulty in balancing the energy consumed by the nodes. Depth‐based routing protocol is an opportunistic routing protocol for underwater sensor networks, which provides good performance both under high and low node mobility scenarios. The main contribution of our work is presenting a novel simulator for studying depth‐based routing protocol and its variants as well as novel routing protocols. Our simulator is based on AquaSim–Next Generation, which is a specialized tool for studying underwater networks. With our work, we improve the state of the art of underwater routing protocol simulators by implementing, among other features, a detailed cross‐layer communication and an accurate model of the operational modes of acoustic modem and their energy consumption. The simulator is open source and freely downloadable. Moreover, we propose a novel and completely distributed routing protocol, named residual energy–depth‐based routing. It takes into account the residual energy at the nodes' batteries to select the forwarder nodes and improve the network lifetime by providing a more uniform energy consumption among them. We compare its performance with that of depth‐based routing protocol and a receiver‐based routing protocol implementing a probabilistic opportunistic forwarding scheme.

Void Avoidance Opportunistic Routing Protocol for Underwater Wireless Sensor Networks

“…Bit Error Rate (BER): We assume that the underwater acoustic micro-modem uses binary phase shift keying (BPSK) modulation [ 17 , 19 , 33 ]. Accordingly, the bit error rate ( P e ) of BPSK in an underwater Rayleigh fading channel can be calculated as in [ 33 ]: where SNR is the signal-to-noise ratio defined by Equation (1).…”

Routing Improvement in Underwater Wireless Sensor Networks for Energy Saving Purposes

“…The routing procedure continues only if the transmitter sensors depth is higher than that of the receiver. The main disadvantages of this protocol are lack of management on the network blind spots (which leads to higher energy consumption and higher end-toend delay), and energy imbalance in the sensor network [6]. CODBR Protocol In wireless sensor networks, due to phenomena such as underwater currents, underwater living creatures, saltwater and due to dispersion and absorption of sound waves, distortion or partial data loss is quite possible.…”

“…Furthermore, several protocols have been developed for energy saving and end-to-end delay reduction in under water wireless networks [4]. Many protocols have been thus developed namely vector base forwarding (VBF) [5], and depth based routing (DBR) [6].…”

Implementation Patterns of AquaSim for Simulation of Underwater Acoustic Wireless Sensor Networks

“…The network topology of the WSNs will range from a simplistic star network to a complex multihop wireless mesh network. The propagation form of the network may be way or flood [5,6,7].…”