Differential aperture coupling technique for passive and active integrated antenna design

A novel contactless method of spatially coupling differential signals from a transmission line to an antenna structure is described. A differential signal is used to generate a current maximum/virtual short circuit under the antenna and electromagnetic energy is efficiently coupled from the transmission line to the antenna via an aperture. Two different passive microstrip patch antenna designs using this differential aperture coupling technique will be demonstrated. This coupling technique has also been successfully applied in an active integrated differential antenna design. Simulation and measurement results are also presented to validate the coupling concept. A simplified transmission line model has also been developed and successfully used to model the differential aperture coupling technique