A study on downsizing of an inverted FL antenna using dielectric materials

Previously, the design of a small inverted FL antenna (InvFLA) that operates at dual-band of 2 GHz and 4 GHz was proposed for the use inside small handset devices. In this paper, we investigate a further miniaturization of InvFLA by adopting a well-known downsizing technique of using dielectric material. By first loading two rectangular dielectric substrates cohesively to the top head of the antenna, and then modifying the connected position between the F and L elements, we found that it is possible to lower two resonant frequencies of InvFLA from 2392 MHz and 4552 MHz to 1960 MHz and 3552 MHz, respectively, without any degradations in radiation property.