Coupling of electromagnetic waves into wires : experiments and simulations
Electromagnetic Compatibility (EMC) problems may occur in many environments. This Thesis considers a particular sub-set of coupling within shielded enclosures. The actual systems studied are the coupling between a dipole and either one or two rods in a screened room and the effect of a cavity and apertures on a signal travelling along a wire. Experiments are described for the screened room which investigate the repeatability of the measurements and the effects of two closely spaced conductors on the coupling results. The cavity experiments also consider the repeatability of the measurements and the effects of the apertures. Transmission-Line Modelling (TLM) is compared with some other popular modelling methods and generally described. It is applied to the modelling of the experimental systems already discussed. An inherent error associated with the modelling of wires in TLM, manifesting itself as an apparent decrease in the resonant frequency of a wire-like structure, is investigated. The source of the error is deduced and a method of minimising it is proposed. The experimental results are applied to the validation of TLM, and its error correction. Very good comparisons between the experiments and simulations are reported. Correlelograms are investigated as a method of comparing the modelled and experimental results.