Fiber Propagation-Induced Mode Partition Noise in Millimeter-Wave Radio-Over-Fiber Systems

In this letter, we study and demonstrate, for the first time, how chromatic dispersion causes laser mode partition noise at millimeter-wave (mm-wave) frequencies. A 60-GHz radio-over-fiber (RoF) transmission system employing an optical frequency comb is theoretically and experimentally investigated. Chromatic dispersion is a limiting factor in RoF systems, which induces power fading and phase noise on the resultant mm-wave beating carriers. Furthermore, experimental measurements in this letter show that when transmitting optical comb spectrum across kilometers of optical fiber, chromatic dispersion destroys partition noise compensation between modes. Therefore, the beat note carrier suffers from intensity noise impairments that degrade the system performance.