We report a new scheme to support, cost efficiently, ultra-dense wavelength division multiplexing (UDWDM) for optical access networks. As validating experiment, we apply phase modulation of a reflective semiconductor optical amplifier (RSOA) at the ONU with a single DEB, and simplified coherent receiver at OFT for upstream. We extend the limited 3-dB modulation bandwidth of available uncooled To-can packaged RSOA (similar to 400 MHz) and operate it at 3.125 Gb/s with the optimal performance for phase modulation using small and large signal measurement characteristics. The optimal condition is selected at input power of 0 dBm, with 70 rnA bias condition. The sensitivities at 3.125 Gbis (at BER=10(-3)) for heterodyne and intradyne detection reach -34.3 dBm and -38.8 dBm, respectively.

Peer Reviewed