Multi-interchannel crosstalk in a DWDM millimeter-wave-band radio-over-fiber

In this paper, we numerically investigate the influence of multi-interchannel optical crosstalk in a 25-GHz spaced dense-wavelength division multiplexing (DWDM) millimeter-wave-band radio-over-fiber (RoF) downlink system. Up to 31 undesired RoF signals were intentionally mixed as the crosstalk with the desired RoF signal. We define the suppression ratio of the crosstalk as the ratio of the mm-wave power of the desired channel to the undesired channels which are estimated from optical spectrum of the detected RoF signal. The simulation results show that the receiver sensitivity degradation due to the crosstalk can be fairly well predicted with the measurable suppression ratio regardless of the total DWDM channel number.