Ultrawideband microstrip integrated‐antenna‐filter

A new three‐port integrated‐antenna‐filter (IAF) module is proposed for ultrawideband applications.The IAF is designed by closely packing a slot antenna and a patch filter on a single substrate. The reflection coefficient, mutual coupling, input impedance, radiation pattern, and insertion loss of the proposed configuration are studied. Since it was found that the mutual coupling between antenna and filter parts of the IAF is very small across a very wide bandwidth, the two parts can be designed almost independently.