Electromagnetic study of coupling between active and passive circuits

In recent years, because of the high density of microwave circuits and the rise of frequency, the conception of global simulators is being studied more and more in many laboratories. These simulators take into account the direct electromagnetic influence between the currents in the active parts of circuits (generally localized) and the passive components (distributed in lines or radiating patches). The modelisations used are of differents types such as finite elements, finite differences in time domain, and integral approaches. Firstly, the author shows how the active elements are taken into account in the different electromagnetic modelisations. The efficiency of a global simulation in relation to the classical representation is demonstrated for a particular case. Secondly, the author´s attention is devoted to a rigorous definition and analysis of sources and active elements in integral methods, which are particularly well adapted for the conception of global simulators. Finally, some examples are given