Aperture coupled, differentially fed planar inverted F antenna

In this paper, a differentially fed single aperture is used to excite an electrically small and unsymmetrical antenna via contact-less feeding. The current maximum below the aperture is generated by an odd-mode signal, rather than the more conventionally used open-circuit stub. The technique offers advantages of tight integration without compromising antenna performance, and enhanced immunity from common mode interference. Simulated and measured 0.9 GHz results, with a planar inverted F antenna (PIFA), suggest potential applications in mobile communication systems.