Full-duplex broadcast RoF-WDM-PON with self-coherent detection and photonic frequency up/down-conversion using SSB pilot-carrier

A novel bidirectional broadcast radio-over-fiber-wavelength division multiplexing-passive optical network (RoF-WDM-PON) based on self-coherent detection and photonic frequency up and down-conversion is presented. In the proposed scheme, a single sideband (SSB) modulated pilot-carrier is transmitted to the optical network unit (ONU), together with the downstream signal by polarization multiplexing on the same fiber link. The SSB pilot-carrier serves as a local oscillator laser to realize coherent detection and an optical carrier of the upstream signal simultaneously. In this way, the optical carrier phase noise and frequency offset in coherent detection have been efficiently eliminated in ONU. Moreover, the detection of the downstream baseband signal and millimeter wave (MMW) signal by homodyne and heterodyne detection can be simultaneously implemented in the proposed scheme. Due to the reuse of SSB light wave, the upstream radio-frequency signal is down-converted at the optical line terminal (OLT) directly by photonic-mixing technique. The performance of proposed RoF-WDM-PON system is evaluated for 20 km signal-mode fiber full-duplex transmission of a 40 Gb/s 16-QAM baseband signal and 10 Gb/s DPSK wireless signal.