Wireless Underwater Broadband and Long Range Communications using Underwater Drones as Data Mules

The underwater communications are essential for the operation and collect large amounts of data (video and images) obtained by Autonomous Underwater Vehicles (AUVs) and remotely controlled underwater vehicles (ROVs) in inspection and monitoring missions at sea. Acoustic waves, despite the high range, allow only narrowband communications, which prevents quick and effective transfer of data. On the other hand, aquatic environment, in particular salt water, severely limits the scope of networks based on electromagnetic waves, having such a range of radius of a few meters. This thesis aims to study and evaluate the use of small vehicles (underwater drones - date mules) capable of transporting data across networks with tolerance to delay (Delay-Tolerant Networks - DTN) between a transmitter and an underwater receiver, taking advantage of high transfer rates at close range. The student must implement a file transfer application that can tolerate high delays in the delivery of information packages. The application will be tested in the underwater environment using the large tank available at INESC TEC and tight cylinder, and compared with simulation results for this scenario. 163/5000 This thesis also presupposes the elaboration of a scientific article for publication in a conference or magazine to disseminate the relevant results of the work.As comunicações subaquáticas são essenciais para a operação e recolha de grandes quantidades de dados (vídeo e imagens) obtidas por Veículos Autónomos Subaquáticos (AUVs) e por veículos subaquáticos controlados remotamente (ROVs) em missões de inspeção e monitorização no mar. As ondas acústicas, apesar do elevado alcance, permitem apenas comunicações de banda estreita, o que inviabiliza a transferência desses dados de forma rápida e eficiente. Por outro lado, o meio aquático, em especial a água salgada, limita severamente o alcance das redes baseadas em ondas eletromagnéticas, tendo estas um raio de alcance de apenas alguns metros. Nesta tese pretende-se estudar e avaliar a utilização de pequenos veículos (drones subaquáticos - data mules) capazes de transportar dados através de redes tolerantes ao atraso (Delay-Tolerant Networks - DTN) entre um emissor e um recetor subaquático, tirando partido das elevadas taxas de transferência a curto alcance. O estudante deverá implementar uma aplicação de transferência de ficheiros capaz de tolerar elevados atrasos na entrega de pacotes de informação. A aplicação será testada em ambiente subaquático recorrendo ao tanque de grandes dimensões disponível no INESC TEC e a cilindros estanques, e comparada com resultados de simulação para esse cenário. Esta tese pressupõe também a elaboração de um artigo científico para publicação em conferência ou revista para disseminação dos resultados relevantes do trabalho

Data Muling for Broadband and Long Range Wireless Underwater Communications

During the past years, there has been an increasing interest in the exploration of underwater wireless communications. This interest has been related mainly to the need for establishing a reliable way of transferring large amounts of data gathered on remote locations in the ocean. This data comes from environmental exploration, oil and gas industries, or marine data from Autonomous Underwater Vehicles (AUVs). These activities require innovative solutions that can provide high bitrates at low costs. With this in mind, and given the current solutions - Optical, Acoustic, and Radio Frequency -, there is the need to create a solution that takes advantage of each technology and overcomes their limitations. In the case of optical communications, they can provide high bitrates, but requires line of sight, and depend significantly on water turbidity. Although acoustic solutions can provide a large range of operation, they have a low bandwidth due to the frequency of operation, and so they are not suitable for transferring high amounts of data. Finally, current radio frequency (RF) solutions allow high bit rates but are limited by the operation range due to the substantial attenuation of electromagnetic waves underwater. With this in mind, it is possible to say that currently, there is no solution for broadband long-range underwater communications. This dissertation aims to develop a solution that allows the increase of throughput and range of underwater wireless communications. To achieve this, a set of underwater data mules will be used. They will take advantage of the high bitrates of RF wireless communications and the long-range associated with acoustic solutions. With this dissertation, communication protocols designed for delay and disruption tolerant networks (DTNs) will be explored, and a protocol that will enable the scheduling of mules will be proposed and implemented, taking advantage of an out-of-band acoustic channel for controlling the mules, and the DTN for data transfer. The solution will be evaluated in a freshwater testbed

Energy Efficiency in Communications and Networks

The topic of "Energy Efficiency in Communications and Networks" attracts growing attention due to economical and environmental reasons. The amount of power consumed by information and communication technologies (ICT) is rapidly increasing, as well as the energy bill of service providers. According to a number of studies, ICT alone is responsible for a percentage which varies from 2% to 10% of the world power consumption. Thus, driving rising cost and sustainability concerns about the energy footprint of the IT infrastructure. Energy-efficiency is an aspect that until recently was only considered for battery driven devices. Today we see energy-efficiency becoming a pervasive issue that will need to be considered in all technology areas from device technology to systems management. This book is seeking to provide a compilation of novel research contributions on hardware design, architectures, protocols and algorithms that will improve the energy efficiency of communication devices and networks and lead to a more energy proportional technology infrastructure

Broadband optical wireless communications for the teleoperation of mining equipment

The current level of technological advancement of our civilization serving more than seven billion human population requires new sources of biotic and abiotic natural resources. The depletion and scarcity of high-grade mineral deposits in dry land are forcing the Natural Re- sources industry to look for alternate sources in underwater environments and outer space, requiring the creation of reliable broadband omnidirectional wireless communication systems that allows the teleoperation of exploration and production equipment. Within these ob- jectives, Optical Wireless Communications (OWC) are starting to be used as an alternative or complement to standard radio systems, due to important advantages that optical wave- lengths have to transmit data: potential for Terabit/s bit rates, broadband operation in underwater environments, energy e ciency and better protection against interference and eavesdropping. This research focus in two crucial design aspects required to implement broadband OWC systems for the teleoperation of mining equipment: high bandwidth wide beam photon emission and low noise omnidirectional Free-Space Optical (FSO) receivers. Novel OWC omnidirectional receivers using guided wavelength-shifting photon concentra- tion are experimented in over 100 meters range vehicle teleoperation.Master of Science (MSc) in Natural Resources Engineerin