Filterless radio-over-fiber system based on polarization multiplexing to generate an 80  GHz millimeter wave

We propose a filterless full-duplex radio-over-fiber system based on polarization multiplexing and demonstrate the generation of an 80 GHz millimeter wave using two Mach-Zehnder modulators. By adjusting the polarization direction, we could generate an 80 GHz frequency millimeter-wave signal and restore the original pure light carrier, providing a light source for the uplink. The simulation results show that the 80 GHz millimeter-wave signal was obtained with a 23.48 dB radio-frequency sideband suppression ratio. Furthermore, we showed that the proposed scheme is relatively flexible and free from the limitation of filter fixed bandwidth in addition to being simple and economical.