Maximum electromagnetic coupling to a nearby conducting strip through narrow and wide slits in a parallel-plate waveguide

The problems involved in electromagnetic coupling to a nearby conducting strip through narrow and wide slits in a parallel-plate waveguide (PPW) are discussed as simplified models of the two-dimensional (2-D) problems of aperture-coupled and proximity-coupled microstrip structures while focusing on radiative coupling mechanisms and perfect matching methods. These matching mechanisms exemplify general matching methods for use in small flush antenna structures. Finally, the similarity between the role of the nearby strip and the phasing unit of the recently reported crossed-field antenna structure is also discussed.