Coplanar waveguide and slot line on magnetic substrates: analysis and experiment

A full-wave analysis is presented for coplanar waveguide (CPW) and slotline phase shifters on magnetic substrates. The analysis is based on a multilayer Green's function which is formulated using a transmission matrix approach. This approach is modified so that its computational efficiency is increased by deriving the transmission matrices for dielectric and ferrite slabs in a closed form. The Green's function is then applied to the full-wave analysis of a slotline and CPW on infinite-width substrates. Several different multilayered configurations are investigated with respect to their nonreciprocal phase-shift properties. Perfectly conducting sidewalls are then added to the analysis and the resulting configuration is used to study the effect of various CPW parameters on differential phase shift. An experimental structure built on the surface of rectangular ferrite toroid is described and its differential phase analysis compared to measurements. Calculated and measured results are in good agreement.< >