TEM-Modes in Slot-Coupled Waveguides

TEM-modes which are usually expressed in terms of a scalar electric potential ÿ are shown to be derivable from a scalar magnetic potential ¿ if the supporting transmission line can be considered a slot coupled waveguide with more than one coupling slot. The magnetic potential must jump at the coupling slots in order to give rise to the axial electric current on the strips separating these slots. The advantage of this formulation is its compatibility to the numerically efficient generalized spectral domain technique which has been successfully applied for the analysis of planar transmission lines. Several multi-slot planar transmission lines have been analyzed using this formulation. Excellent agreement with the results obtained by other methods have been achieved with extremely low cup-time and storage requirements.