A class of enhanced electromagnetically coupled feed geometries for printed antenna applications

The authors discuss a few selected geometries of aperture-proximity-coupled printed antennas with enhanced performance. Relevant electrical characteristics of each geometry are studied in the context of analytical results obtained using a generalized analysis routine developed at the University of Massachusetts. This analysis routine, UNIFY (for unified analysis of arbitrary geometries of multilayered printed antennas), can treat many possible variations of feed lines, radiating elements, and multilayer geometries and can model infinite arrays, as well as isolated (single) elements. This unified analysis uses a spectral-domain Galerkin moment method and a multiport scattering matrix formulation for the multiple feed lines using reciprocity argument; it handles the arbitrary multilayer substrate geometry by the spectral-domain Green´s functions for multilayered substrates. The analysis is full wave in all respects and accounts for all surface-wave and modal coupling effects.<>