A novel combined WDM-PON with a single shared DI using downlink DPSK and uplink remodulated OOK signals

We propose a novel downlink optical carrier remodulated wavelength-division-multiplexed passive optical network (WDM-PON) architecture, in which two WDM-PONs whose wavelength locate in different wavebands share a single delay interferometer (DI) in remote node (RN) to demodulate the downlink data simultaneously. 10-Gb/s downlink differential phase-shift-keying (DPSK) signal and 1.25-Gb/s remodulated uplink On-Off keying (OOK) signal are generated and measured. Experiment results show that crosstalk between the two WDM-PONs is negligible even though the two PONs share a single DI. With our novel scheme, the single DI can be shared by more users in different PONs, which can reduce the cost of optical network unit (ONU). Meanwhile, Rayleigh backscattering noise is eliminated by combining these two PONs with different wavebands.