A peripherally fed broadband modified circular microstrip antenna

A new method for enhancing the impedance bandwidth of a circular microstrip antenna is presented. The technique used is to slightly perturb the circular symmetry by a peripheral cut. Unlike the circular patch the modified structure can be matched to a microstrip line along the periphery. Also the antenna exhibits polarisation diversity (with feed location). The radiation characteristics of the antenna are not affected by this structural modification. This new antenna may find applications in large broadband phased arrays with complex corporate peripheral microstrip line feed networks.