Wireless industrial monitoring and control networks: the journey so far and the road ahead

While traditional wired communication technologies have played a crucial role in industrial monitoring and control networks over the past few decades, they are increasingly proving to be inadequate to meet the highly dynamic and stringent demands of today’s industrial applications, primarily due to the very rigid nature of wired infrastructures. Wireless technology, however, through its increased pervasiveness, has the potential to revolutionize the industry, not only by mitigating the problems faced by wired solutions, but also by introducing a completely new class of applications. While present day wireless technologies made some preliminary inroads in the monitoring domain, they still have severe limitations especially when real-time, reliable distributed control operations are concerned. This article provides the reader with an overview of existing wireless technologies commonly used in the monitoring and control industry. It highlights the pros and cons of each technology and assesses the degree to which each technology is able to meet the stringent demands of industrial monitoring and control networks. Additionally, it summarizes mechanisms proposed by academia, especially serving critical applications by addressing the real-time and reliability requirements of industrial process automation. The article also describes certain key research problems from the physical layer communication for sensor networks and the wireless networking perspective that have yet to be addressed to allow the successful use of wireless technologies in industrial monitoring and control networks

Game Theory-Based Cooperation for Underwater Acoustic Sensor Networks: Taxonomy, Review, Research Challenges and Directions.

Exploring and monitoring the underwater world using underwater sensors is drawing a lot of attention these days. In this field cooperation between acoustic sensor nodes has been a critical problem due to the challenging features such as acoustic channel failure (sound signal), long propagation delay of acoustic signal, limited bandwidth and loss of connectivity. There are several proposed methods to improve cooperation between the nodes by incorporating information/game theory in the node's cooperation. However, there is a need to classify the existing works and demonstrate their performance in addressing the cooperation issue. In this paper, we have conducted a review to investigate various factors affecting cooperation in underwater acoustic sensor networks. We study various cooperation techniques used for underwater acoustic sensor networks from different perspectives, with a concentration on communication reliability, energy consumption, and security and present a taxonomy for underwater cooperation. Moreover, we further review how the game theory can be applied to make the nodes cooperate with each other. We further analyze different cooperative game methods, where their performance on different metrics is compared. Finally, open issues and future research direction in underwater acoustic sensor networks are highlighted

A NEW ENERGY EFFICIENT ADAPTIVE HYBRID ERROR CORRECTION TECHNIQUE FOR UNDERWATER WIRELESS SENSORS NETWORKS

Underwater wireless sensors networks find many applications in today's life. However underwater sensors are still relatively expensive. They suffer from short lifetime which is limited by batteries lifetime as it is difficult to recharge or even replace batteries in harsh aquatic medium. When the battery is depleted the sensor is of no use anymore. So designing energy efficient communication protocols is an important issue for underwater sensors networks. Underwater is characterized by variable channel conditions, whereas underwater sensors are mobile due to water currents leading to variable distances between sensors. This variability in channel conditions and distances between sensors leads to inefficiency in energy consumptions when using fixed type of error correction technique. In this thesis, a mathematical energy efficiency derivations for the two main error correction techniques (Automatic Repeat request (ARQ) and Forward Error Correction (FEC)) in underwater environment has been done. The results from those derivations show that one technique is more energy efficient than the other below specific distance, where as the other is more energy efficient after this distance. This specific distance is found to be unfixed and varies with the variation in channel conditions and packet size. So using fixed error correction technique for specific distance is not accurate. Simulation has been done which validate the mathematical derivations. Based on the above derivation results Adaptive Hybrid Error Correction (AHEC) technique which adaptively changes the error correction technique to the technique that gives the highest energy efficiency for the current channel conditions and distances has been proposed. The technique uses an adaptation algorithm which depends on a pre-calculated packet acceptance rate (PAR) ranges look-up table, current PAR, packet length and current error correction technique used. AHEC viii technique has been found to have better energy saving compared with the techniques that depend on pure ARQ or FEC only. This saving ranges from 10 to 70 % in energy saving in ARQ case , and 7 to 10 % in energy saving in FEC case depending on current channel conditions and distance .It has also been compared with the technique that uses variable power supply in adaptation (Adaptive Variable Power Supply (AVPS)) and it achieves between 20 to 60 % in energy saving depending on current channel conditions and distance. It has also been compared with Adaptive Redundancy Reliable Transport Protocol (ARRTP), and it achieves between 10 to 80 % in energy saving depending on the current channel conditions and distance. The adaptation algorithm which depends on PAR has also been applied in adaptation to the ARRTP which originally depends only on inter-node distance in adaptation. PAR take both of distance and channel conditions into consideration. This technique is called PAR-based ARRTP, and the results shows better adaptation than the basic ARRTP in variable channel conditions cases. AHEC technique has also been applied with the bounded distance routing protocol to minimize the effects of variable channel conditions. Bounded distance routing protocol design depends on choosing specific number of relays between sender and receiver that minimize the total energy consumptions. This specific number of relays varies with the variation in channel conditions. The results show a deviation in number of relays from 6 when fixed error correction technique is used to only 2 when AHEC technique is used with it

Radio Communications

In the last decades the restless evolution of information and communication technologies (ICT) brought to a deep transformation of our habits. The growth of the Internet and the advances in hardware and software implementations modified our way to communicate and to share information. In this book, an overview of the major issues faced today by researchers in the field of radio communications is given through 35 high quality chapters written by specialists working in universities and research centers all over the world. Various aspects will be deeply discussed: channel modeling, beamforming, multiple antennas, cooperative networks, opportunistic scheduling, advanced admission control, handover management, systems performance assessment, routing issues in mobility conditions, localization, web security. Advanced techniques for the radio resource management will be discussed both in single and multiple radio technologies; either in infrastructure, mesh or ad hoc networks

Cooperative medium access control based on spectrum leasing

Based on cooperative spectrum leasing, a distributed “win–win” (WW) cooperative framework is designed to encourage the licensed source node (SN) to lease some part of its spectral resources to the unlicensed relay node (RN) for the sake of simultaneously improving the SN’s achievable rate and for reducing the energy consumption (EC). The potential candidate RNs carry out autonomous decisions concerning whether to contend for a cooperative transmission opportunity, which could dissipate some of their battery power, while conveying their traffic in light of their individual service requirements. Furthermore, a WW cooperative medium-access-control (MAC) protocol is designed to implement the proposed distributed WW cooperative framework. Simulation results demonstrate that our WW cooperative MAC protocol is capable of providing both substantial rate improvements and considerable energy savings for the cooperative spectrum leasing system

Study on Packet Forwarding Mechanism by Narrowing Relay Range in Ad Hoc Networks

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