EFFECT OF FINITE CONDUCTIVITY ON DISPERSION CHARACTERISTICS OF GRATING WAVE-GUIDE

We present here a systematic investigation of dielectric waveguide loa ded with a metal-strip grating which is realistically characterized by a complex dielectric constant with a negative imaginary part to accou nt for the finite conductivity of the metal strips. The method of mode matching is employed to solve such a boundary-value problem, and the effects of the structure parameters on the dispersion characteristics are critically examined, with a particular attention directed toward t he attenuation constant due to the Bragg reflection, radiation and abs orption of the grating waveguide.