We propose and experimentally demonstrate a novel ring-based wavelength-division-multiplexing passive optical network (WDM-PON). By using an orthogonal coding and correlation technique, the ring-based WDM-PON can efficiently mitigate the optical beat interference noise induced by Rayleigh backscattering. In our proposed orthogonal coding scheme, no extra light sources are required for the upstream (US) transmission, which means the number of light sources can be halved and the saved wavelengths can be used for more optical network units. In add...
