All-Optical Distribution Node for Long Reach PON Downlink

A simple photonic circuit is proposed for all-optical distribution of long-reach passive optical networks (PONs) aggregated in a WDM distribution trunk. The circuit can distribute a WDM comb in C-band carrying G- and/or XG-PON channels into a number of downlink fibers and it is also able to convert the signals to standard PON wavelengths (1500 nm for G-PON and 1570 nm for XG-PON). The circuit is based on parallel cross gain modulation between WDM signals in C-band and continuous wave probes at destination downlink wavelengths. A proof-of-concept experimental demonstration is reported showing a maximum 3-dB power penalty for operation at 10 Gb/s in the counter-propagating case. Broadband operation is also reported for input signals in the whole C-band.