Compact PIFA for 2.4/5 GHz dual ISM-band applications

A compact and novel modified planar inverted-F antenna (PIFA) for dual ISM-band application is proposed. The proposed antenna, including a small ground plane, occupies a volume of 20*23.7*0.8 mm/sup 3/ (FR-4). The impedance bandwidth with 10 dB return loss is about 150 MHz (2380-2530 MHz) for 2.4 GHz band and 1450 MHz (5130-6580 MHz) for 5 GHz band. The measured radiation patterns are approximately omnidirectional and yield a gain of 1.0 dBi at 2440 MHz and 3.98 dBi at 5600 MHz, respectively.