A miniaturized multiband reconfigurable fractal slot antenna for GPS/GNSS/Bluetooth/WiMAX/X-band applications

A novel miniaturized multiband reconfigurable fractal slot antenna for switchable GPS/GNSS/Bluetooth/WiMax/X-band is reported. By utilizing a Koch fractal in the radiating part miniaturization of about 78.8% and 86% are achieved in volume and active patch area respectively. Multiband operations at 1.47–1.65 GHz (BW = 11.5%) GPS, 2.2–2.43 GHz (BW = 9.9%) Bluetooth, 3.4–3.89 GHz (BW = 13.4%) middle WiMAX, 5.61–5.84 GHz (BW = 4%) upper WiMAX and 9.8–10.73 GHz (BW = 9.05%) X-band, are achieved by slotted ground approach in conjunction with Complementary Split Ring Resonator (CSRR). Frequency reconfiguration characteristics in the antenna is accomplished by placing a PIN diode in the ground plane; thus making the antenna to exhibit switchable radiations at 1.91–2.34 GHz (BW = 20.73%) Bluetooth, 3.72–3.89 GHz (BW = 4.46%) middle WiMAX, 4.92–5.33 GHz (BW = 8.0%) upper WiMAX and 10.16–10.70 GHz (BW = 5.1%) X-band, under “ON” condition. During “OFF” condition, antenna exhibits switchable performances at 1.59–1.84 GHz (BW = 14.57%) GPS/GNSS, 3.77–4.12 GHz (BW = 8.87%) middle WiMAX, 5.1–5.35 GHz (BW = 4.78%) upper WiMAX and 10.27–10.62 GHz (BW = 3.35%) X-band. The antenna has a compact area of 35 × 30 mm², and exhibits acceptable gain, stable radiation patterns and good impedance matching at the targeted frequencies.