Novel highly-directive Fabry-Perot (FP) type antennas with significantly enhanced bandwidth performance based on periodic metasurfaces are presented in this thesis. The proposed antennas are formed by multiple layers of periodic surfaces and metasurfaces placed over a ground pla…
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As a result of decades of research and innovation in the renewable energy industry, advanced technologies have been developed for both wind and solar energy conversion systems. However, there are still some aspects of the systems that need to be enhanced to enable maximum and co…
Power-switching devices require low on-state conduction losses, high-switching speed, high thermal stability, and high input impedance. Using gallium nitride (GaN) based field-effect transistors, these properties for switching devices can be satisfied. GaN-based High Electron Mo…
This research project investigates the development and validation of alternative simulation models for voltage source inverter fed permanent magnet synchronous machine drive systems which can rapidly and accurately analyse and evaluate the performance of PM machine drives and as…
Fossil fuels, which are the main energy sources of the current world, are running low and alternative ways of generating and storing different types of energies are becoming daunting missions. Renewable energy is very attractive because the source of the energy is often free and…
Dynamic Demand Technology (DDT) developed by Open Energi Ltd. adjusts the power consumption of demand to react rapidly to changes in grid frequency without undermining the inherent control of loads. In this thesis, DDT is used to regulate the power consumption of domestic refrig…
This thesis provides an in-depth investigation and evaluation of infrared optical wireless MIMO communication systems to be applied in both indoor and outdoor environment. The principle objective of the research is to demonstrate both the advantages and disadvantages of the opti…
This thesis explores, by means of modelling and physical experiments, variant designs for triskelion devices, a type of planar exure mechanism widely considered for use in micro-probe suspensions and, more recently, force transfer artefacts. The accurate measurement of low force…
Detailed characterisation of the structure of subsurface fractures is greatly facilitated by digital borehole logging instruments, however, the interpretation of which is typically time-consuming and labour-intensive. Despite recent advances towards autonomy and automation, the …
In the last decade, miniaturised “lab-on-a-chip” (LOC) devices have attracted significant interest in academia and industry. LOC sensors for electrochemical analysis now commonly reach picomolar in sensitivities, using only microliter-sized samples. One of the major drawbacks of…
This thesis presents work on antennas and propagation for WBANs at 60 GHz. First, a compact, wearable Vivaldi antenna and Vivaldi antenna array covering the whole unlicensed band from 57 to 64 GHz are proposed to overcome the shadowing due to human movements. Second, multi-hop c…
In the majority of microwave receiving and transmitting systems, a requirement is to have a filter immediately adjacent to the antenna or antenna array. This thesis presents a new methodology for antenna design where a filter is either fully or partially integrated with the ante…
Speech signals contain important information about a speaker, such as age, gender, language, accent, and emotional/psychological state. Automatic recognition of these types of characteristics has a wide range of commercial, medical and forensic applications such as interactive v…
Non-orthogonal multiple access (NOMA) allows allocating one carrier to more than one user at the same time in one cell. It is a promising technology to provide high throughput due to carrier reuse within a cell. In this thesis, a novel interference cancellation (IC) technique is…
This thesis focuses on developing a testing method to estimate the mechanical and electrical characteristics of CNT-based contact surfaces. In particular the use of gold thin films deposited on a CNT forest has potential to offer a very effective contact surface. Two different p…
The field of science whose goal is to assign each input object to one of the given set of categories is called pattern recognition. A standard pattern recognition system can be divided into two main components, feature extraction and pattern classification. During the process of…
Growing energy demand and climate change due to increasing CO2 emissions are two major global issues. The development of Supergrids, which involves connecting national energy supply grids together via interconnections, has been proposed as a measure to overcome these challenges.…
Smart grid has been advocated in both developing and developed countries in many years to deal with large amount of energy deficit and air pollutions. However, many literatures talked about some specific technologies and implementations, few of them could give a clear picture on…
This study is a trans-disciplinary and trans-historical investigation into civilian and battlefield contexts in which speaker systems have been utilised by the military-industrial and military-entertainment complexes to apply pressure to mass social groupings and the individuate…