Improving bandwidth of printed rectangular monopole antenna

Abstract

This paper proposes a rectangular printed monopole antenna where systematic study has been carried out to increase the bandwidth of the antenna. A few techniques are applied to obtain large impedance bandwidth for printed rectangular monopole antenna with reduced substrate size. With proper optimisation of slot dimensions and microstrip line feed position gives increased impedance bandwidth. Simple printed rectangular antenna, without slot and offset feed, shows 1.2:1 (1.94 GHz to 2.30 GHz) and 1.65:1(3.5 GHz to 5.8 GHz) impedance bandwidth ratio for VSWR <= 2 for the first band. Whereas, for various presented band enhancing techniques, Bandwidth increases upto 3.82 GHz from 0.36 GHz. The radiation patterns in azimuthal and elevation planes are reasonably good. Index Terms-Printed Rectangular Monopole antenna, Slot cut, offset feed, microstrip line feed, broadband antenna.