Method of moment based analysis of a broadband optical receiver

To provide the requested high band-widths for modern communications the combination of optical and wireless links in Radio-over-Fiber systems (RoF), is expected to be an essential part of next generation wireless communication systems. A crucial part of these links is the broadband optical receiver transforming the signal from high optical to millimeter-wave frequencies at each base station. A new integrated optical receiver chip with an integrated antenna structure supporting more than 100GHz bandwidth is available. To be compatible to standard millimeter-wave components based on hollow metal waveguide structures an efficient coupling solution from the chip to waveguide has to be designed. For the performance of this element the impedance matching to the integrated photo diode is the dominating task. Therefore models of the chip structure with different complexity and computational effort were created and numerically simulated using the Method of Moments and compared with analytical models and empirical results. Since the computational effort of the whole structure is high, it is of interest to what detail the structure has to be modeled for an efficient design process of a coupling solution to a hollow metal waveguide. Radiation patterns of the models are investigated in order to determine a suitable coupling direction.