Wideband dual polarized compact design of pi-shape microstrip antenna for GSM, ISM, and satellite applications

The design of a compact Pi-shape microstrip antenna for dual-polarized wideband response is proposed. The Pi-shape geometry is realized by modifying a compact C-shape patch. The two stubs placed on the Pi-shape patch edge optimize the spacing in between the higher order TM20 and TM30 resonant modes with respect to the fundamental TM10 mode which yield a bandwidth of more than 430MHz (> 35%). On an air suspended substrate, the antenna exhibits broadside gain of more than 5 dBi over the impedance bandwidth. The orthogonal surface current variations across the TM10, TM20, and TM30 modes realize polarization agility satisfying the requirements of GSM900/navigation satellite applications/ISM900. With respect to the band start frequency, the proposed configuration offers 11% reduction as compared with the equivalent rectangular microstrip antenna. Further, by defining the resonant length at each of the Pi-shape patch modes, the formulation for their resonant frequency is proposed. The Pi-shape antennas redesigned using them at the given fundamental mode frequency yield similar dual polarized wideband responses offering bandwidth of > 35%. © 2021, Electromagnetics Academy. All rights reserved.