Microwave simulation of optoelectronic bending loss in presence of dielectric discontinuity

A theory is developed and compared with experimental results. The theory enables calculation of the curvature loss from a partially buried dielectric waveguide in the presence of a strong air/dielectric planar interface. Comparison is made between numerical predictions based on this theory and experimental results for a smooth waveguide of rectangular cross-section. Agreement is found to be striking, even when the position of the caustic should, in theory, render the waveguide lossy.