Mitigation of interferometric crosstalk by using a single mode laser with optical feedback in a loop-back WDM-PON based on RSOA

To alleviate the back-reflection induced interferometric crosstalk in a loop-back WDM-PON based on RSOA, we propose the use of off-the-shelf single mode operated laser with intentional optical feedback as a seeding source. For adjusting the external optical feedback quantity, we could effectively broaden the spectral linewidth of single mode operated laser output. We also experimentally demonstrated that our proposed method could enhance the up- and down-stream transmission performances under relatively lower signal to crosstalk ratio.

► We propose simple method to alleviate the reflection penalty in a seeded WDM-PON.
► We employed single mode laser with intentional optical feedback as a seeding source.
► Using our proposal, improvement of the up- and down-link performances was confirmed.
► Our proposal will have a great impact on the high-speed, long-reach WDM-PON systems.