Shorting strap tunable dual-band stacked PIFA

RF switches are integrated to the shorting straps of a stacked planar inverted-F antenna (PIFA) to make a tunable PIFA. The L-band switch yields a 0.45 dB insertion loss (IL) and 10 dB isolation bandwidth (BW) of 40% at 1.5 GHz. The tunable PIFA yields 17.2% impedance BW at 744.7 MHz when varying numbers of upper radiating patch´s shorting straps are connected to the ground electronically via PIN diode switches, and 20% BW at 1137 MHz when lower radiating patch´s shorting straps are tuned. Thus an infinite combination of individual frequency tuning by shorting straps of the stacked patch PIFA is possible.