A novel frequency reconfigurable monopole antenna using PIN diode for WLAN/WIMAX applications

A frequency reconfigurable microstrip monopole antenna for WLAN/WiMax applications is proposed in this paper. The antenna uses three PIN diodes for the aim of achieving frequency reconfigurability. By switching the state of PIN diodes, the antenna is capable of operating at four different frequency bands with the center resonant frequencies of 2.4 Ghz, 3.3 GHz, 5.1 GHz and 5.6 GHz. The radiation pattern of the antenna is similar at all configurations. In different switching states, the antenna operates in single band mode. The dimension parameters of the antenna are calculated using some theoretical formula, simulated and optimized using CST software. The results in dimension parameter between calculating and simulating are relatively the same. The antenna is fabricated on FR4 substrate with a size of 40 X 30 mm, a thickness of 1.6 mm, and the relative permittivity of 4.4. A good agreement has been observed between the resonate frequency of measurement and simulation.