A rigorous and computationally efficient analysis of microstrip for use as an electro-optic modulator

Much interest has been shown in the literature concerning the direct modulation of an optical signal by a microwave signal using a microstriplike structure with a diffused optical waveguide. Due to the particular geometry of the modulator, the usual rigorous methods of analysis, such as the spectral-domain method (SDM), encounter problems, and less efficient methods have had to be used. It is shown that by using an asymptotic form of the Green´s function in the standard SDM, an accurate, efficient, and rigorous full-wave analysis can readily be undertaken. A closed-form first-order solution to the field patterns is also derived