Moment method analysis of dispersion in SRR-type FSS loaded rectangular waveguides using spectral domain green’s functions and RWG basis functions

This work has extended a previously devised moment-method treatment of sidewall loaded rectangular waveguides with periodic metallizations (FSS) imprinted on the dielectric surfaces. Arbitrarily shaped inclusions can now be treated with RWG basis functions. The SRR-type inclusions have been chosen for illustration here. The extended numerical code has been able to demonstrate the characteristic attributes of such SRR- FSS loaded waveguides, particularly the existence of bandgaps and backward propagating modes within a narrow passband below the ordinary modal cutoff frequency. The dispersion graphs generated by this code also checks well with those obtained by CST simulations.