Simulation and Analysis of a T-Slot Coupled Microstrip Antenna with CPW-Fed using Ansoft HFSS

some analysis has been presented on a circularly polarized microstrip antenna with T slot configurations in detail. Here we will design a T-slot coupled circularly polarized microstrip antenna in the frequency 1.575 GHz. The upper patch i.e. the radiating patch would be circular. There is no closed form expression so that by using that expression the dimensions of the proposed antenna could be determined theoretically. But for the simple circular patch antenna we could use an expression (obtained from cavity model analysis) to obtain the patch radius at a particular frequency. So the final dimensions of the proposed antenna would be obtained starting from very simple structure such as circular patch antenna to the proposed complex structure antenna. The simulation of this T-slot coupled circularly polarized microstrip antenna has been performed using the commercial software ansoft HFSS. Initially optimized dimension obtained for the antenna which provides satisfactory result further these dimensions of circular patch microstrip antenna is modified to obtain a good directivity as well as impedance matching at frequency 1.575 GHz. By varying the antenna parameters attention is also paid to obtained good axial ratio.