Optical phase noise modeling for heterodyne radio over fiber systems

In this paper, the optical phase noise of the semiconductor laser is integrated with its electrical equivalent circuit (large signal model) to perform a system modeling approach. The model is employed in a heterodyne radio over fiber (RoF) system where two distributed feedback (DFB) lasers are used to generate a millimeter-wave (mm-wave) signal. An optical phase-locked loop (OPLL) is also introduced to reduce the phase noise on the generated mm-wave signal. With the developed model, phase noise contribution of individual lasers is evaluated even with more complex systems like OPLL in purely microwave simulator.