Concentric annular ring microstrip antenna array

Theoretical investigations conducted on gap coupled annular ring microstrip antenna is found to exhibit frequency tunability with the gap. The various parameters of the antenna such as input impedance, VSWR, return loss and radiation pattern have been investigated as a function of gap length and feed point. It is found that the various parameters of gap coupled microstrip antenna dependent heavily on the gap length and feed points. The radiated power of antenna also depends on the gap length.