Equivalent Circuit Analysis of Position-Dependent Surface Wave Coupling Efficiency In Metasurfaces

Efficient application of metasurfaces as surface waveguides depends on a well-designed launcher to maximise the in- and out-coupling. By considering the case of a square patch unit cell and an aperture surface wave launcher, we build up a procedure to analyse the interactions between a launcher and a metasurface through equivalent circuit models. This analysis identifies that the coupling efficiency depends on the position of the launcher due to the interactions between the launcher and the small-scale structures of the metasurface.