Medium Access Control and Routing Protocols Design for 5G

In future wireless systems, such as 5G and beyond, the current dominating human-centric communication systems will be complemented by a tremendous increase in the number of smart devices, equipped with radio devices, possibly sensors, and uniquely addressable. This will result in explosion of wireless traffic volume, and consequently exponential growth in demand of radio spectrum. There are different engineering techniques for resolving the cost and scarcity of radio spectrum such as coexistence of diverse devices on the same pool of radio resources, spectrum aggregations, adoption of mmWave bands with huge spectrum, etc. The aim of this thesis is to investigate Medium Access Control (MAC) and routing protocols for 5G and beyond radio networks. Two scenarios are addressed: heterogeneous scenario where scheduled and uncoordinated users coexist, and a scenario where drones are used for monitoring a given area. In the heterogeneous scenario scheduled users are synchronised with the Base Station (BS) and rely on centralised resource scheduler for assignment of time slots, while the uncoordinated users are asynchronous with each other and the BS and rely unslotted Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) for channel access. First, we address a single-hop network with advanced scheduling algorithm design and packet length adaptation schemes design. Second, we address a multi-hop network with novel routing protocol for enhancing performance of the scheduled users in terms of throughput, and coexistence of all network users. In the drone-based scenario, new routing protocols are designed to address the problems of Wireless Mesh Networks with monitoring drones. In particular, a novel optimised Hybrid Wireless Mesh Protocol (O-HWMP) for a quick and efficient discovery of paths is designed, and a capacity achieving routing and scheduling algorithm, called backpressure, investigated. To improve on the long-end-to-end delays of classical backpressure, a modified backpressure algorithm is proposed and evaluated

UAV-to-Ground Multi-Hop Communication Using Backpressure and FlashLinQ-Based Algorithms

The use of Unmanned Aerial Vehicles (UAVs) for remote sensing and surveillance applications has become increasingly popular in the last decades. This paper investigates the communication between a UAV and a final control center (CC), using static relays located on the ground, to overcome the intermittent connectivity between the two end points, due to the UAV flight. Backpressure and FlashLinQ routing and scheduling algorithms are jointly applied to this scenario. Backpressure has been shown to be able stabilize any input traffic within the network capacity region without requiring knowledge of traffic arrival rates and channel state probabilities. FlashLinQ is used in the scheduling phase to derive a maximal feasible subset of links which can coexist on a given slot without causing harmful interference to each other. Moreover, to overcome the limit on long end-to-end delays of backpressure, we propose a modified algorithm, where relays are selected depending on their proximity to the CC and on the UAV trajectory. Through extensive simulations, we demonstrate that, compared to the benchmark solution based on backpressure, the proposed algorithm is able to reduce delay significantly without any loss in throughput gain

Wireless Mesh Networks for IoT and Smart Cities: Technologies and Applications

Wireless mesh networks (WMNs) are wireless communication networks organized in a mesh topology with radio capabilities. These networks can self-form and self-heal and are not restricted to a specific technology or communication protocol. They provide flexible yet reliable connectivity that cellular networks cannot deliver. Thanks to technological advances in machine learning, software defined radio, UAV/UGV, big data, IoT and smart cities, wireless mesh networks have found much renewed interest for communication network applications. This edited book covers state of the art research innovations and future directions in this field. WMNs offer attractive communication solutions in difficult environments such as emergency situations, battlefield surveillance, field operations, disaster recovery, tunnels, oil rigs, high-speed mobile-video applications on board transport, VoIP, and self-organizing internet access for communities. The main topics covered include BLL-based mesh networks, body sensor networks, seamless IoT mobile sensing through Wi-Fi mesh networking, software defined radio for wireless mesh networks, UAV-to-ground multi-hop communication using backpressure and FlashLinQ-based algorithms, unmanned aerial vehicle relay networks, multimedia content delivery in wireless mesh networking, adaptive fuzzy agents in big data and multi-sensor environments and AI-aided resource sharing for WMNs. This is a useful reference for ICT networking engineers, researchers, scientists, engineers, advanced students and lecturers in both academia and industry working on wireless communications and WMNs. It is also relevant to developers, designers and manufacturers of WMNs and wireless sensor networks (WSNs); and scientists and engineers working on applications of WNNs and WSNs