Dual-frequency broadband antenna for mobile device applications

Abstract

This paper proposes a low profile monopole antenna which achieves a dual-frequency broadband operation at 900 MHz with a bandwidth of ∼42% (790∼1215) and at 1900 MHz with a bandwidth ∼53% (1710∼3000 MHz). The proposed antenna has an inverted F strip and a meandered strip directly fed by the microstrip line on the front side and has an S strip terminated at a ground plane. The lower sections of the inverted F strip and the S strip overlap and form a two-strip monopole. The mutual coupling of the two-strip lines has a significant effect on the bandwidth enhancement. The Antenna structure is described in detail and its performance is validated by experimental results.