Investigation of a short-range underwater acoustic communication channel for MAC protocol design

Abstract

Mobile swarms of autonomous underwater vehicles (AUV) have exciting potential for extending current AUV applications and adding new possibilities to the working environment of the oceans. For swarm operations to occur, fast reliable communication between all vehicles within the swarm is needed. The challenge for underwater communication is the very different and unique characteristics of the channel compared to the terrestrial environment. Acoustic communication has been the typical physical layer technology used for underwater operations and has experienced significant research and progress over the last few decades, however this focus has been predominately on longer range acoustic channels. The work presented in this paper is to determine the critical parameters of an underwater acoustic communication channel for the evaluation and development of a new MAC Protocol designed for short range communication between vehicles operating within a swarm. This paper provides a review of the essential channel characteristics and the modelling currently in use for this purpose, highlighting the difference for short range operations. It then assesses the electro-acoustic interface with investigation into the parametric relationship between digital modulation requirements and short range channel characteristics.

On Securing Underwater Acoustic Networks: A Survey

“…Plentiful underwater noises also impact underwater channel quality, mainly including ocean ambient noise and self-noise of vessels [38]- [41]. They affect acoustic communication at different frequencies roughly as follows: turbulence noise for frequencies less than 10 Hz, shipping noise for frequencies between 10 and 100 Hz, wave and other surface motion caused by wind and rain for 100 Hz∼100 kHz, and thermal noise for frequencies over 100 kHz [41]. Furthermore, underwater acoustic channel quality may also change in very short time scale [35], [42].…”

CUMAC-CAM: a channel allocation aware MAC protocol for addressing triple hidden terminal problems in multi-channel UWSNs

“…UWSN came up to researchers as an interesting research area for the last few years due to the fact of ocean exploration improvement and fulfillment of numbers of underwater applications [6]. Unlike electromagnetic waves, underwater acoustic channels are characterized by a long propagation delay, high path loss, low data rates, and a limited bandwidth [7][8][9]. Furthermore, energy required to transmit data in acoustic channels is almost 100 times than the energy required to receive data [10,11].…”

Challenges, Threats, Security Issues and New Trends of Underwater Wireless Sensor Networks

“…The ambient noises include: the radiated noises and self-noises from vessels, noises caused by waves and other surface motions; turbulence noise, thermal noise, and the noises that come from marine animals. These ambient noises can be classified into four types that affect acoustic communication at different frequency band, including turbulence noise ( N t , less than 10 Hz), shipping noise ( N s , 10–100 Hz), wind noise ( N w , 100 Hz–100 kHz), and thermal noise ( N th , over 100 kHz) [ 10 ]. These ambient noises can be calculated by the following empirical equations in dB, which is a function of frequency: where w is the speed of sea-surface wind in m/s.…”