Improved bandwidth and F/B ratio of a CPW-fed planar monopole antenna.

A directional planar monopole antenna is described. The antenna comprises of a circular monopole, coplanar waveguide (CPW) feed line and a ground plane. To achieve unidirectional radiation, a stub is also attached to on the ground plane to increase the lower end impedance bandwidth and also increase the Front-to-Back ratio (F/B). The proposed antenna is etched on a 50 × 50 mm2 FR4 substrate. Simulated and experimental results reveal that the proposed antenna can achieve an impedance bandwidth from 2.3 - 10.5 GHz for S11 < -10 dB, and unidirectional radiation patterns with high gain and high efficiency.