Resonant feeding networks for microstrip antennas

A novel technique for feeding microstrip antennas is proposed. The feeding network, made of microstrip lines, is designed to propagate standing waves, instead of traveling waves as is usually done. At its resonance, the incident and reflected signals combine with each other, resulting in a stable and periodic field distribution along this network. Thus, coupled patches can be excited with equal magnitude, and either equal phase or phase opposition, depending on the desired radiation pattern. They also bring an additional resonance, which, added to that of the patch, enhances the input impedance bandwidth. No power dividers or matching stubs are necessary, leading to structural simplicity. Three examples of resonant feeding networks are presented, which provide three different resonating modes.<>