Simulating the response of coupled channel and interferometric modulator designs

An algorithm is developed that enables the response of a large class of electrooptic modulator designs to be calculated quickly and accurately. Using this algorithm, a computer program can be developed that allows the following responses to be accurately calculated and displayed in real-time: intensity versus voltage, optical phase versus voltage, the output spectrum for any one or two-tone input, the dynamic response of the nonlinear distortion products, and the frequency response of the fundamental and nonlinear signals. By properly time sampling the modulator output in response to a one or two-tone input, an accurate modulator simulation can be accomplished with a minimal number of calculations. Such a program is useful in the development of novel modulator designs and in evaluating the tolerance of various aspects of modulator performance to variations in fabrication and passive bias control. Furthermore, the ability to determine the frequency response of the nonlinear distortion is significant in itself. In this paper, a detailed description of the algorithm is presented which includes an optimized sampling technique for both the one and two-tone tests. Several new results obtained with this method are also presented