Impact of Relative Intensity Noise on 60-GHz Radio-Over-Fiber Wireless Transmission Systems

This paper investigates a 60-GHz radio-over-fiber (RoF) communication system employing two different techniques to generate millimeter-wave (mm-wave) signals. The relative intensity noise (RIN) transferred during optical heterodyning of mm-wave signal is theoretically studied and experimentally investigated. Laser RIN induces noise at resultant electrical mm-wave signal and is directly generated from initial RIN at low frequency. Therefore, RIN impairs the performance of the mm-wave RoF system. The model of RIN is also presented and is in very close agreement with the experiment results. Furthermore, wireless transmission experiments to demonstrate the intensity noise effect are carried out and are compliant with the communication standards at mm-wave. Wireless transmission up to 3 m can be achieved using a transmit power of +4.5 dBm.