5-Gb/s optical transmitter based on incoherent-light-injected RSOAs with graceful upgrade capability for WDM PONs

Zaineb Al-Qazwini,Hoon Kim

doi:10.1364/oe.21.008135

Abstract

We propose and demonstrate a novel and cost-effective optical transmitter based on incoherent-light-injected reflective semiconductor optical amplifiers (RSOAs) which can be upgraded to higher data rate without discarding the existing low-data-rate transmitter. The transmitter is based on optical time-division multiplexing (OTDM) of return-to-zero modulated RSOAs and thus capable of upgrading the system capacity on an as-needed basis simply by adding RSOAs. By using the proposed transmitter, we experimentally demonstrate a capacity upgrade from 2.5 to 5 Gb/s/channel by using two RSOAs, each operating at 2.5 Gb/s. To the best of our knowledge, this is the highest reported data rate demonstrated using incoherent-light-injected RSOAs. We also demonstrate the performance of the proposed transmitter after 10-km transmission over standard single-mode fiber, and investigate the sensitivity penalty to the power level injected into the RSOAs as well as the optical delay for the OTDM.

Highlights

As the internet data traffic is expected to grow by 50~60% every year in the foreseeable future, wavelength-division-multiplexed (WDM) passive optical networks (PONs) are regarded as the most future-proof solution to address the growing bandwidth demands for next-generation broadband access networks
Broadband incoherent light generated by an Erbiumdoped fiber amplifier (EDFA) is first spectrum-sliced by an arrayed waveguide grating (AWG) to produce multi-channel continuous-wave incoherent light and fed to reflective semiconductor optical amplifiers (RSOAs) or Fabry-Pérot laser diodes (FP-LDs) for data modulation
We propose a novel and cost-effective optical transmitter for WDM PONs based on amplified spontaneous emission (ASE)-injected RSOAs with graceful upgrade capability

Summary

Introduction

As the internet data traffic is expected to grow by 50~60% every year in the foreseeable future, wavelength-division-multiplexed (WDM) passive optical networks (PONs) are regarded as the most future-proof solution to address the growing bandwidth demands for next-generation broadband access networks They leverage the benefits of passive infrastructure, but they provide high capacity, network flexibility, infrastructure sharing, and high security [1,2]. Among several proposed candidates, amplified spontaneous emission (ASE)-injected reflective semiconductor optical amplifiers (RSOAs) or Fabry-Pérot laser diodes (FP-LDs) offer a very attractive solution for both downstream and upstream transmission [6,7,8,9] In these schemes, broadband incoherent light generated by an Erbiumdoped fiber amplifier (EDFA) is first spectrum-sliced by an arrayed waveguide grating (AWG) to produce multi-channel continuous-wave incoherent light and fed to RSOAs or FP-LDs for data modulation. To the best of our knowledge, 5 Gb/s is the highest data rate demonstrated by using ASE-injected RSOAs or FP-LDs

System architecture

Experiment and results

Summary