Developments in the application of the geometrical theory of diffraction and computer graphics to aircraft inter-antenna coupling analysis

This thesis examines the need for a systematic methodology for the analysis of aircraft electromagnetic compatibility (EMC) problems. It surveys the available computer aids used in aircraft EMC analysis and establishes the theoretical basis for the complex algorithms which identify and quantify electromagnetic interactions. The thesis presents an overview of one particularly well-established aircraft antenna-to-antenna EMC analysis code: the Aircraft Inter-Antenna Propagation with Graphics (AAPG) Version 07 (V07) software program. The thesis discusses the specific new algorithms that have been created to compute cone geodesics and their associated path losses, and to graphically portray representations of the physical coupling path. These algorithms are validated against basic principles. Loss computations apply the Uniform Geometrical Theory of Diffraction (UTD) and are subsequently compared to measurement data. The thesis assesses the increased modelling and analysis capabilities of the newly developed AAPG Version 09 (V09) against those of AAPG V07. Several models of a "real-world" aircraft, namely the Electronics Systems Trainer (EST) Challenger, are generated and are provided as the basis for this preliminary comparative assessment. Issues such as software reliability, algorithm stability, and quality of hardcopy output are also discussed. This comparative study opens several avenues for future researc