Coplanar Versus Slotline Mode in Exciting CPW-FED Planar Antennas

In this paper we report on the first theoretical analysis of feeding planar antennas with the slotline mode of the CPW. The analysis is carried out using a mixed potential integral equation formulation, MPIE, solved with the method of moments, MoM. The analysis is applied on a CPW-fed cusp antnna The theoretical results include the return loss and the radiation patterns associated with both the coplanar and the slotline modes. Experiments are also performed and their results for the coplanar mode are presented. The agreement between theory and experiments for the coplanar mode validates the theory and the presented results for the slotline mode.