Analysis of feeding techniques of rectangular microstrip antenna

Microstrip antennas are excited for radiation modes using different techniques which lead to best impedance matching between the feed line and the patch. This paper describes two techniques which use microstrip line and also coaxial line as feed line for a rectangular patch. The analysis was carried out using ANSOFT High frequency structure simulator (HFSS). By changing the position of the feed point and using inset feed design, the return loss at the feed point was determined at 2.4GHz and the results were compared with those obtained for coaxial line feed from HFSS analysis. It is concluded that coaxial line feed is best of all techniques if bandwidth is not a factor.