The contributions of this thesis are four fold. Firstly, the implementation of COST 259 directional channel model in terms of tapped delay line is developed. While the implemented channel model facilities link level simulation, capacity analysis indicates that the delay spread has relatively small impact as compared to the azimuth spread (AS) on the channel capacity. Secondly, an antenna model which incorporates various antenna effects into the performance study of antenna arrays (AAs0 is developed. A comprehensive study of these effects through computer simulations reveals that the use of ideal parameters in the literature always over-predicts the actual system performance. The use of different antenna configurations yields different results with some arrays performing better in certain scenario than others. Furthermore, a proposed mutual coupling (MC) model explains the conflicting results reported to date in the literature. The overall effect of MC is to reduce the system performance despite lower fading correlation is being obtained between the pair of elements when MC is taken into account. Thirdly, the impact of using different azimuth-of-arrival (AOA) and elevation-of-arrival (EOA) distributions on the performance of various AAs is found to be minimal. The determining factor for the AA performance is the standard deviation of the underlying distribution. Finally, three-dimensional spatial fading correlation (SFC) models for several CAA geometries are developed. The closed-form SFC functions are expressed in terms of AOA, EOA and the geometry of the AA under study. Such closed-form expressions can be used to determine the correlation matrices at both base station and mobile station and thus are important in assisting the capacity analysis of single-input multiple-output and multiple-input and multiple-output systems. Furthermore, the developed SFC functions also enable the sensitivity of the AAs to be evaluated through the performance patterns. The results provide invaluable insight that can ultimately assist the design of AA algorithms. An extensive analysis on the array’s sensitivity shows that the system performance is more AS dependent than ES while the effect of mean-azimuth-of-arrival and mean-evaluation-of-arrival is array dependent. The results also show that the AS is the primary factor affecting antenna correlation and the impact of ES is mainly noticeable at small AS values. Nevertheless, in evaluating the performance of AAs, both AOQ and EOA must be taken in account. Capacity analysis also demonstrates the practicability of deploying electromagnetic vector sensor (EVS) and EVS arrays as compact AA receivers.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:664134 |
| Date | January 2003 |
| Creators | Yong, Su-Khiong |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/11648 |
Page generated in 0.0017 seconds