The modelling of nonlinear effects using time domain integralequations

摘要

The authors review techniques for the mathematical modelling ofnelectromagnetic coupling to circuit boards and systems and theirnexperimental validation on a time domain measurement facility based atnthe Royal Signals and Radar Establishment (RSRE) Pershore. Two keynfeatures of this work are the very wide bandwidth signals consideredn(signals with bandwidths from about 100 MHz up to 2 or 3 GHz) and thenpresence of nonlinear loads such as transistors and diodes. Thenmodelling problem is handled by combining two areas of work; namely timendomain integral equations and nonlinear systems theory. The formerncombines fast computation of nonlinear problems with a clear physicalninterpretation of cause and effect. The latter permits analysis ofnnonlinear coupling problems and complements the direct numericalnapproach by identifying generic properties of the circuit and predictingnthresholds for complex behaviour