Transfer function simulation of all-air-gap filters based on eigenmodes

The analysis of filter devices based on eigenmodes provides a facile and fast means to simulate the reflection and transmission function and shows good agreement with the measurements. The computing time is proportional to the number of eigenmodes, and the analysis yields an analytical expression for the transfer functions. The method can be easily applied on the analysis of geometries which are not rotationally symmetric. The coupling with different source fields of an arbitrary shape can be handled without recomputing the eigenmodes.