Filtering slot antenna using coupled line resonator

This paper presents the design of a novel slot filtering antenna suitable for modern electronic devices integrating various wireless systems that have to coexist. The approach consists in feeding the slot antenna through a filtering microstrip-to-slot-line transition. This transition comprises a coupled line resonator which enables to create two out-of-band transmission zeros and by this way to increase drastically the frequency selectivity of the transition. As proof-of-concept, a slot filtering antenna has been designed for WLAN applications operating in the 2.4GHz band, by using the HFSSTM simulation tool. A prototype has been also fabricated, using a low-cost FR4 substrate, where 2 antennas are printed on a board in order to accommodate the requirements of a 2×2 MIMO system.