Investigation of ultra-wideband wireless communication inside electromagnetically ultra small confined environments

Thesis

Ultra-wideband (UWB) communication has been the subject of extensive research in recent years due to its unique capabilities and potential applications, particularly in short-range multiple access wireless communications. However, many important aspects of UWB-based communication systems have not yet been thoroughly investigated. The propagation of UWB signals inside very small enclosed environments is one of the important issues with significant impacts on the future direction, scope, and generally the extent of the success of UWB technology. The objective of this thesis is to obtain a more thorough and comprehensive understanding of ultra-small UWB channels for communication applications and design issues for enhancing the data rate of UWB systems. This works supports the postulation of a high capacity UWB wireless interconnect scheme for communicating devices within conducting enclosures – a wireless “backplane”.

This thesis proposes the use of an Ultra-Wide Bandwidth (UWB) ultra-small scale wireless interconnect scheme for use within electrically small enclosures. Such ultra-small environments (size ≤ 10 wavelengths) are topologically much more complex, being more cluttered, than typical indoor environments (size ≥ 10 wavelengths). The concept is presented through two different scenarios. Firstly, a PC Tower case is presented as a model environment and the work seeks to present the optimum channel performance, where EMI issues are discussed and problem avoidance proposed. Secondly, in order to extrapolate the different results from the study inside the PC, an investigation is carried out using an Aluminium tower case as a more generic model environment. The analysis is based on the behaviour of box modes within a conducting resonator enclosure and the effective communications bandwidth for UWB systems for different sizes and components within.

From these general considerations the research presents theoretical and experimental results from which are derived the communications metrics measured within enclosures. Simulations of the different scenarios are performed using different techniques such as ray tracing and a full wave model, based on CST Microstripes. Empirical data is recorded using a vector network analyser (VNA)-based wideband channel sounding system where channel measurements are carried out in every scenario regarding different aspects such as frequency response and time domain analysis, evaluation of the channel capacity, power delay study and the nature of the environment.

Authors: Gelabert, J

• Publication date: 2012
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: Oxford University, UK
• Language: English
• Keywords: ultra wide band; wireless; channel characterization
• Subjects: Electrical engineering; Telecommunications engineering