Wide-band planar inverted-F antenna for cognitive radio

A wide-band Planar Inverted-F Antenna (PIFA) is presented. The proposed antenna is simply structured consist of main patch supported by shorting wall and shorting pin, fed by 50 ohm microstrip transmission line. The antenna achieves an enhanced impedance bandwidth of 64.5 % covering from 2.1 to 4.1GHz with a stable radiation performance in terms of gain from 6–8 dBi. The radiated patch occupied a total volume of 53 × 55 mm. The antenna was studied by means of numerical simulation; the achieved −10 dB bandwidth of the antenna is confirmed and demonstrated by experimental measurements. The simulated and measured results are in good agreements.