Low-Profile Loop-Shaped Inverted-F Wire Antenna With Dual-Mode Operation

In this letter, we propose a new structure for a dual-mode antenna. We introduce a loop-shaped inverted-F wire antenna (LIFA) that has small and low-profile structure and uses a parasitic element (PE) within the feeding element for the additional resonance mode. We present a theoretical discussion on the dual-resonance operation and investigate the characteristics along some dimensional parameters using numerical analyses. The measurement results with the proposed structure are also presented.