Modified Analysis of Traveling Wave Modulator and Active Directional Coupler with Coplanar Electrodes

This algorithm presented a simple analysis of traveling wave modulator (TWM) and active directional coupler, ADC, with coplanar electrodes. In this algorithm, the electrooptic material, EOM, is treated as anisotropic-homogenous material before and after the applied electric field by using the average values of the d.c electric field components, E_xav and E_yav, instead of the varying components, E_x(x,y) and E_y(x,y). In this algorithm, for TWM, the mismatch velocity between microwave and optical waves has been improved by controlling the external drive voltage, to increase the optical effective refractive index, LiNbO₃ is the best EOM. Also, for ADC, two waveguides propagation constants, coupling coefficient, C, and transferred power between ADC waveguides are controlled by an applied voltage C between two similar and dissimilar EOMs is evaluated. Two similar EOMs act as dissimilar materials with different orientation of crystallographic axes. Excellent pair of EOMs depend upon electrodes configurations. This algorithm permits finding the effect of all modulator and coupler parameters on the performance of them