Enhancement of reflection tolerance in a bidirectional WDM-PON based on RSOA employing near-threshold operated DFB laser as a seed light

We successfully enhanced reflection tolerance in a single fiber bidirectional WDM-PON based on RSOA where DFB laser diode is utilized as a seeding source. We propose to operate DFB laser diode at its near threshold regime to broaden its spectral linewidth. With such a broadened linewidth, the back-reflection induced beating noise is mitigated, and we can achieve the BER below 10
⁻¹⁰
over 20km under −32 dB link reflection.