Compact differential hollow dielectric resonator antenna with embedded vertical feed

The compact differential hollow dielectric resonator antenna (DRA) with an embedded vertical feed is investigated. A printed 180° hybrid rat-race is deployed as the feed network. The vertical feed network has a very small footprint, giving more space for placing microwave components. For demonstration, a hollow cylindrical differential DRA was designed at ∲2.4 GHz for WLAN applications. The reflection coefficient, antenna gain, and radiation pattern were simulated using ANSYS HFSS. The simulated results were verified by measurements, and reasonable agreement between the measurement and simulation is observed.