MAC/Routing design for under water sensor networks

The huge advances in communication technologies and Micro Electrical and Mechanical Systems (MEMS) have triggered a revolution in sensor networks. One major application of sensor networks is in the investigation of complex and uninhabited under water surfaces; such sensor networks are called the Underwater Wireless Sensor Networks (UWSN). UWSN comprises of a number of sensors which are submerged in water and one or several surface stations or a sinks at which the sensed data is collected. In some underwater sensor applications, autonomous underwater vehicles (AUVs) could be used. The underwater sensor nodes communicate with each other using acoustic signals. Applications for this type of networks include oceanographic data collection, pollution monitoring, offshore exploration and tactical surveillance applications. The novel networking paradigm of UWSN is facing a totally different operating environment than the ground based wireless sensor networks. This introduces new challenges such as huge propagation delays, and limited acoustic link capacity with high attenuation factors. These new challenges have their own impact on the design of most of the networking layers preventing researchers from using the same layers used for other networks. The most affected layers are the Physical, Medium Access Control (MAC), Routing and Transport layers. This work will introduce novel routing and MAC layers’ protocols for UWSNs. The routing protocol will adopt the minimum spanning tree algorithm and focus on maximizing the connectivity of the network, which means maximizing the total number of nodes connected to the root or the sink in this case. The protocol will try also to provide a minimum hop connection for all the nodes in the network taking into account the residual energy, location information and number of children at the next hop node. The other contribution of this work is a MAC Protocol which will incorporate the topology information provided by the routing protocol to minimize the collisions and energy wastage in data transmission. The MAC Protocol will also try to shorten the queuing delays at the intermediate nodes for a message traveling from source to the sink. A comparison will be conducted with other existing routing and MAC protocols. The routing protocol will be tested and compared with the E-Span spanning tree algorithm for data aggregation. The MAC protocol will be compared with Park\u27s protocol proposed in [2] in terms of performance metrics like end-to-end delay and the number of collisions. We will also explore the ability of the proposed protocols to enhance the life span of the network

Enhancing Security and Energy Efficiency in Wireless Sensor Network Routing with IOT Challenges: A Thorough Review

Wireless sensor networks (WSNs) have emerged as a crucial component in the field of networking due to their cost-effectiveness, efficiency, and compact size, making them invaluable for various applications. However, as the reliance on WSN-dependent applications continues to grow, these networks grapple with inherent limitations such as memory and computational constraints. Therefore, effective solutions require immediate attention, especially in the age of the Internet of Things (IoT), which largely relies on the effectiveness of WSNs. This study undertakes a comprehensive review of research conducted between 2018 and 2020, categorizing it into six main domains: 1) Providing an overview of WSN applications, management, and security considerations. 2) Focusing on routing and energy-saving techniques. 3) Reviewing the development of methods for information gathering, emphasizing data integrity and privacy. 4) Emphasizing connectivity and positioning techniques. 5) Examining studies that explore the integration of IoT technology into WSNs with an eye on secure data transmission. 6) Highlighting research efforts aimed at energy efficiency. The study addresses the motivation behind employing WSN applications in IoT technologies, as well as the challenges, obstructions, and solutions related to their application and development. It underscores that energy consumption remains a paramount issue in WSNs, with untapped potential for improving energy efficiency while ensuring robust security. Furthermore, it identifies existing approaches' weaknesses, rendering them inadequate for achieving energy-efficient routing in secure WSNs. This review sheds light on the critical challenges and opportunities in the field, contributing to a deeper understanding of WSNs and their role in secure IoT applications

Enhancement of precise underwater object localization

Underwater communication applications extensively use localization services for object identification. Because of their significant impact on ocean exploration and monitoring, underwater wireless sensor networks (UWSN) are becoming increasingly popular, and acoustic communications have largely overtaken radio frequency (RF) broadcasts as the dominant means of communication. The two localization methods that are most frequently employed are those that estimate the angle of arrival (AOA) and the time difference of arrival (TDoA). The military and civilian sectors rely heavily on UWSN for object identification in the underwater environment. As a result, there is a need in UWSN for an accurate localization technique that accounts for dynamic nature of the underwater environment. Time and position data are the two key parameters to accurately define the position of an object. Moreover, due to climate change there is now a need to constrain energy consumption by UWSN to limit carbon emission to meet net-zero target by 2050. To meet these challenges, we have developed an efficient localization algorithm for determining an object position based on the angle and distance of arrival of beacon signals. We have considered the factors like sensor nodes not being in time sync with each other and the fact that the speed of sound varies in water. Our simulation results show that the proposed approach can achieve great localization accuracy while accounting for temporal synchronization inaccuracies. When compared to existing localization approaches, the mean estimation error (MEE) and energy consumption figures, the proposed approach outperforms them. The MEEs is shown to vary between 84.2154m and 93.8275m for four trials, 61.2256m and 92.7956m for eight trials, and 42.6584m and 119.5228m for twelve trials. Comparatively, the distance-based measurements show higher accuracy than the angle-based measurements

Secure Energy Aware Optimal Routing using Reinforcement Learning-based Decision-Making with a Hybrid Optimization Algorithm in MANET

Mobile ad hoc networks (MANETs) are wireless networks that are perfect for applications such as special outdoor events, communications in areas without wireless infrastructure, crises and natural disasters, and military activities because they do not require any preexisting network infrastructure and can be deployed quickly. Mobile ad hoc networks can be made to last longer through the use of clustering, which is one of the most effective uses of energy. Security is a key issue in the development of ad hoc networks. Many studies have been conducted on how to reduce the energy expenditure of the nodes in this network. The majority of these approaches might conserve energy and extend the life of the nodes. The major goal of this research is to develop an energy-aware, secure mechanism for MANETs. Secure Energy Aware Reinforcement Learning based Decision Making with Hybrid Optimization Algorithm (RL-DMHOA) is proposed for detecting the malicious node in the network. With the assistance of the optimization algorithm, data can be transferred more efficiently by choosing aggregation points that allow individual nodes to conserve power The optimum path is chosen by combining the Particle Swarm Optimization (PSO) and the Bat Algorithm (BA) to create a fitness function that maximizes across-cluster distance, delay, and node energy. Three state-of-the-art methods are compared to the suggested method on a variety of metrics. Throughput of 94.8 percent, average latency of 28.1 percent, malicious detection rate of 91.4 percent, packet delivery ratio of 92.4 percent, and network lifetime of 85.2 percent are all attained with the suggested RL-DMHOA approach

Smart Wireless Sensor Networks

The recent development of communication and sensor technology results in the growth of a new attractive and challenging area - wireless sensor networks (WSNs). A wireless sensor network which consists of a large number of sensor nodes is deployed in environmental fields to serve various applications. Facilitated with the ability of wireless communication and intelligent computation, these nodes become smart sensors which do not only perceive ambient physical parameters but also be able to process information, cooperate with each other and self-organize into the network. These new features assist the sensor nodes as well as the network to operate more efficiently in terms of both data acquisition and energy consumption. Special purposes of the applications require design and operation of WSNs different from conventional networks such as the internet. The network design must take into account of the objectives of specific applications. The nature of deployed environment must be considered. The limited of sensor nodes� resources such as memory, computational ability, communication bandwidth and energy source are the challenges in network design. A smart wireless sensor network must be able to deal with these constraints as well as to guarantee the connectivity, coverage, reliability and security of network's operation for a maximized lifetime. This book discusses various aspects of designing such smart wireless sensor networks. Main topics includes: design methodologies, network protocols and algorithms, quality of service management, coverage optimization, time synchronization and security techniques for sensor networks

Cooperative mobility maintenance techniques for information extraction from mobile wireless sensor networks

Recent advances in the development of microprocessors, microsensors, ad-hoc wireless networking and information fusion algorithms led to increasingly capable Wireless Sensor Networks (WSNs). Besides severe resource constraints, sensor nodes mobility is considered a fundamental characteristic of WSNs. Information Extraction (IE) is a key research area within WSNs that has been characterised in a variety of ways, ranging from a description of its purposes to reasonably abstract models of its processes and components. The problem of IE is a challenging task in mobile WSNs for several reasons including: the topology changes rapidly; calculation of trajectories and velocities is not a trivial task; increased data loss and data delivery delays; and other context and application specific challenges. These challenges offer fundamentally new research problems. There is a wide body of literature about IE from static WSNs. These approaches are proved to be effective and efficient. However, there are few attempts to address the problem of IE from mobile WSNs. These attempts dealt with mobility as the need arises and do not deal with the fundamental challenges and variations introduced by mobility on the WSNs. The aim of this thesis is to develop a solution for IE from mobile WSNs. This aim is achieved through the development of a middle-layer solution, which enables IE approaches that were designed for the static WSNs to operate in the presence of multiple mobile nodes. This thesis contributes toward the design of a new self-stabilisation algorithm that provides autonomous adaptability against nodes mobility in a transparent manner to both upper network layers and user applications. In addition, this thesis proposes a dynamic network partitioning protocol to achieve high quality of information, scalability and load balancing. The proposed solution is flexible, may be applied to different application domains, and less complex than many existing approaches. The simplicity of the solutions neither demands great computational efforts nor large amounts of energy conservation. Intensive simulation experiments with real-life parameters provide evidence of the efficiency of the proposed solution. Performance experimentations demonstrate that the integrated DNP/SS protocol outperforms its rival in the literature in terms of timeliness (by up to 22%), packet delivery ratio (by up to 13%), network scalability (by up to 25%), network lifetime (by up to 40.6%), and energy consumption (by up to 39.5%). Furthermore, it proves that DNP/SS successfully allows the deployment of static-oriented IE approaches in hybrid networks without any modifications or adaptations

A wireless sensor network system for border security and crossing detection

The protection of long stretches of countries’ borders has posed a number of challenges. Effective and continuous monitoring of a border requires the implementation of multi-surveillance technologies, such as Wireless Sensor Networks (WSN), that work as an integrated unit to meet the desired goals. The research presented in this thesis investigates the application of topologically Linear WSN (LWSNs) to international border monitoring and surveillance. The main research questions studied here are: What is the best form of node deployment and hierarchy? What is the minimum number of sensor nodes to achieve k− barrier coverage in a given belt region? iven an appropriate network density, how do we determine if a region is indeed k−barrier covered? What are the factors that affect barrier coverage? How to organise nodes into logical segments to perform in-network processing of data? How to transfer information from the networks to the end users while maintaining critical QoS measures such as timeliness and accuracy. To address these questions, we propose an architecture that specifies a mechanism to assign nodes to various network levels depending on their location. These levels are used by a cross-layer communication protocol to achieve data delivery at the lowest possible cost and minimal delivery delay. Building on this levelled architecture, we study the formation of weak and strong barriers and how they determine border crossing detection probability. We propose new method to calculate the required node density to provide higher intruder detection rate. Then, we study the effect of people movement models on the border crossing detection probability. At the data link layer, new energy balancing along with shifted MAC protocol are introduced to further increase the network lifetime and delivery speed. In addition, at network layer, a routing protocol called Level Division raph (LD ) is developed. LD utilises a complex link cost measurement to insure best QoS data delivery to the sink node at the lowest possible cost. The proposed system has the ability to work independently or cooperatively with other monitoring technologies, such as drowns and mobile monitoring stations. The performance of the proposed work is extensively evaluated analytically and in simulation using real-life conditions and parameters. The simulation results show significant performance gains when comparing LD to its best rivals in the literature Dynamic Source Routing. Compared to DSR, LD achieves higher performance in terms of average end-to-end delays by up to 95%, packet delivery ratio by up to 20%, and throughput by up to 60%, while maintaining similar performance in terms of normalised routing load and energy consumption

A High-speed Reconfigurable Free Space Optical Communication System Utilizing Software Defined Radio Environment

Free space optical (FSO) communication allows for high-speed data transmissions while also being extremely cost-effective by using visible or infrared wavelengths to transmit and receive data wirelessly through the free space channel. However, FSO links are highly susceptible to the effects of the atmosphere, particularly turbulence, smoke, and fog. On the other hand, FSO itself does not provide enough flexibility to address the issue of such blockage and obstruction caused by objects and atmospheric conditions. This research investigates, proposes, and evaluates a software defined multiple input multiple output (MIMO) FSO system to ensure link availability and reliability under weather conditions as part of the last mile access in the 5th generation, 6th generation, and beyond. Software defined radio (SDR) technology is adopted in order to provide a certain degree of flexibility to the optical wireless communications system. The scope of this research focuses on the design, validation, implementation, and evaluation of a novel adaptive switching algorithm i.e., activating additional transmitters of a MIMO FSO system using a software defined ecosystem. The main issues are the compactness of the experimental design; the limitation of software-oriented signal generation; robustness; reliability; and the quality of service. As part of the system design, the thresholding method, a decision-making process via the feedback link, and a spatial diversity technique is adopted to carry out the adaptive switching. The adaptive switching is performed via a feedback link in which the atmospheric loss and scintillation index are calculated for fog and turbulence respectively. The initial design is implemented in SDR/ GNURadio for a real-time emulation of the proposed system to enhance the system flexibility of a traditional MIMO FSO system. A bit-by-bit comparison is performed with the GNURadio signal processing block and BERT for a real-time BER estimation. However, based on the initial results, the switching mechanism can only overcome the effect of turbulence at a certain level. A new design to mainly mitigate the varying fog conditions is proposed based on the SDR-based adaptive switching for a gigabit ethernet (GbE) MIMO FSO system and tested in a 5 m dedicated atmospheric chamber. The proposed system is implemented using off-the-shelf components such as a media converter, small form pluggable transceivers, optical switch, and power meter to estimate the channel state information. A new Schmitt trigger-based thresholding method is also introduced. The proposed software defined GbE MIMO FSO with an adaptive switching algorithm is fabricated, implemented, and investigated. The results are also compared with the real-time simulated data. Since the purpose of this Ph.D. is to explain and demonstrate the proof of concept for the proposed SDR-MIMO FSO system, the emphasis has been on the design, evaluation, and minimal performance requirements rather than maximizing the data rate. The outcome of the thesis will be a huge degree of flexibility and mitigation property MIMO FSO can offer with the help of SDR. It will be shown that the designed system has the capability to provide data transmission with 99.999% availability with a packet error rate and data rate of 7.2 ×10−2 and ~120 Mbps respectively, under extremely harsh fog conditions with visibility V of < 11 m

PERFORMANCE & SIMULATION ANALYSIS OF SENSOR AREA COVERAGE

Wireless sensor networks (WSNs) have been employed in numerous military and civilian applications. Some application areas are in battlefield, surveillance, biological detection, and environmental monitoring. A major challenge to such applications is the sensor areacoverage (SAC), which refers to the techniques and mechanisms of placing sensors and their coordination in a mission space (field) to monitor the physical environment in such a way to achieve the application coverage objectives. This thesis develops a sensor area coverage package (SACPac) that simulates some selected coverage algorithms and their enhancements, and analyzes their performance parameters under various scenarios. The performance parameters considered include coverage ratio, resiliency of the field coverage against sensor failures, energy efficiency, and security of communication among sensors. The thesis also develops a prototype of communication for sending the position of an object via a mobile device to the server on which SACPac runs, so that the object trajectory can be displayed. SACPac provides the foundation for further enhancements and future research. It can also be used as an educational tool for those interested in the SAC problem

Aerial Vehicles

This book contains 35 chapters written by experts in developing techniques for making aerial vehicles more intelligent, more reliable, more flexible in use, and safer in operation.It will also serve as an inspiration for further improvement of the design and application of aeral vehicles. The advanced techniques and research described here may also be applicable to other high-tech areas such as robotics, avionics, vetronics, and space