An invisible vehicle roof antenna

Abstract

An invisible vehicle roof antenna for the long term evolution (LTE) application is proposed. The antenna is a bended ultra-wideband monopole with a low profile of 30 mm and covers the LTE operation bands. The antenna is embedded into a hole with a depth of 30 mm which is opened on the roof and is surrounded by metal. The antenna becomes completely invisible when the hole is covered by a dielectric lid. A slit is made on the horizontal part of the antenna to suppress a zenith-directional radiation so that the antenna has enough gain in horizontal directions, even the antenna is surrounded by the metal wall of the hole. The antenna has a dimension of 85×85×30 mm3 and is embedded into a hole of 200×200×30 mm3.