Planar Reconfigurable Multifunctional Antenna for WLAN/Wimax/UWB/Pcsdcs/UMTS Applications

A wideband slotted multifunctional reconfigurable antenna is proposed for WLAN/WiMAX/UWB/PCS-DCS/UMTS applications. The proposed antenna consists of monopole and spiral sections and microstrip feeding. A microstrip patch on FR4 substrate provides wideband return loss for each application. Total area of the antenna is 34×45 mm that satisfies all the requirements for different applications in a low profile structure. Reconfigurable design is used in this antenna using RF MEMS switches. The proposed antenna has a nearly omnidirectional radiation patterns (doughnut shape) in different frequency bands. The notch is embedded in the ground plane to improve the impedance matching, and the dimensions of this notch are optimized. Moreover, the variation of group delay is about ±2 ns in UWB application. Also a prototype of the proposed antenna is fabricated, and the results are compared with those obtained from simulations. Measured return losses are in good agreement with simulated ones. The proposed antenna has the advantages of multifunctional operation, low profile, low cost and omnidirectional pattern.