Demonstration of Receiver Generated Optical Duobinary and VSB-NRZ for Next-Generation PON

We present experimental demonstration of receiver generated optical duobinary (ODB) format for downstream and vestigial sideband non-return to zero (VSB-NRZ) format for upstream in a next-generation passive optical network (NG-PON). Both formats are generated at the respective receivers by a single optical bandpass filter simplifying the design of the optical network unit (ONU) when compared with Mach Zehnder delay interferometer (MZDI) based detection. The optical line terminal (OLT) transmits a differential phase shift keying (DPSK) signal to take advantage of greater tolerance to fiber non-linear effects, which is then converted to ODB format at the ONU receiver for simple direct detection. VSB-NRZ in upstream is generated by adding a bandpass filter at OLT receiver instead of ONU transmitter to keep its design simple. The system presented here obtained a reach of 25 km on standard single mode fiber (SSMF) with C-band wavelengths for both down and upstream without using any dispersion compensation. The 1:64 split was emulated using an optical attenuator while using only a single transmitter and receiver pair at the ONU.