Optimised Ray Tracing for the SuperNEC Implementation of the Uniform Theory of Diffraction

• Main Author: Hartleb, Robert
• Format: Others
• Language: en
• Published: 2007
• Subjects: uniform theory of diffraction; geometrical optimisations; ray tracing
• Online Access: http://hdl.handle.net/10539/2121

Student Number : 0006329K - MSc(Eng) Dissertation - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment === Geometric optimisations are presented for the UTD in SuperNEC which is a commercial electromagnetic software package. Path finding optimisations rapidly find propagation paths of electromagnetic waves by using back face culling to determine the visible plates of polyhedral structures and by using reflection and diffraction zones which use image theory and the law of diffraction to determine illuminated spatial regions. An octree reduces the number of intersections during the shadow tests. Numerical results show that overall the optimisations halve the run time of the software for models which consist of plates and cylinders. The path finding optimisations do not scale with model size, are limited to plates and introduce errors. The mean absolute error due to the path finding optimisations is on average 0:02 dB for first order rays and 0:17 dB for second order rays. The octree optimisation scales with model size, can be used with any geometry and any type of ray and does not cause errors.