Dual-Band Decoupling for Two Back-to-Back PIFAs

In this communication, two dual-band back-to-back planar inverted-F antennas (PIFAs) are presented for wireless local area network (WLAN) applications. By simply etching a slot on the PIFA, the PIFA can simultaneously radiate at the WLAN 2.4 GHz (2.4–2.484 GHz) and WLAN 5 GHz (5.15–5.835 GHz) bands. To reduce the mutual coupling at the two independent bands in a guided way, long and short slots are successively engraved on the ground. The detailed decoupling process is given and discussed. The antenna was fabricated and measured. The measured results show that the two PIFAs cover the 2.4 and 5 GHz WLAN bands and the isolation can be improved to higher than 20 dB at the two independent bands.