September 04, 2017

Raman Fibre Laser Based Amplification in Long-haul/ Unrepeatered Coherent Transmission Systems

  • Ian. D. Phillips
  • Md Asif Iqbal
  • Mingming Tan
  • Paul Harper
  • Pawe³ Rosa
  • Sergei K. Turitsyn
  • Thai Le S.

The paper reviews recent advances of Raman fibre laser (RFL) based amplification techniques in long-haul/unrepeatered coherent transmission systems. Different aspects of theRFL based amplification have been characterised, including signal power distributions and relative intensity noise (RIN). Various RFL based amplifier designs were evaluated in long-haul coherent transmission systems. The results showed that Fabry-Perot fibre laser based amplifier with two fibre Bragg gratings (FBGs) gave significant Q factor penalty using symmetrical bidirectional pumping, as the RIN of the signal was increased dramatically. However, random distributed feedback fibre laser based amplifier with one FBG can mitigate the RIN of the signal, which enables the use of bidirectional second order pumping and therefore gives the best transmission performance up to 7915 km. Furthermore, using random DFB fibre laser based amplifier has been proven to be effective to combat nonlinear impairment. In addition, unrepeatered transmission over >350 km fibre length using RFL based amplification technique has been demonstrated experimentally using DP-QPSK WDM signals.

View Original Article

Recent Publications

January 01, 2018

Fair Dynamic Spectrum Management for QRD-Based Precoding with User Encoding Ordering in Downstream Transmission

In next generation DSL networks such as, employing discrete multi-tone transmission in high frequencies up to 212 MHz, the crosstalk among lines reaches very high levels. To precompensate the crosstalk in downstream transmission, QRD-based precoding has been proposed as a near-optimal dynamic spectrum management (DSM) technique. However, the performance ...

January 01, 2018

Practical Mitigation of Passive Intermodulation in Microstrip Circuits

This paper presents new experimental evidence and a novel practical approach for mitigation of passive intermodulation (PIM) in microstrip circuits fabricated on commercial printed circuit board laminates. The mechanisms of distributed PIM in microstrip circuits are reviewed and a phenomenology of PIM generation due to locally enhanced electromagnetic fields at ...

January 01, 2018

Efficient Cooperative HARQ for Multi-Source Multi-Relay Wireless Networks

In this paper, we compare the performance of three different cooperative Hybrid Automatic Repeat reQuest (HARQ) protocols for slow-fading half-duplex orthogonal multiple access multiple relay channel. Channel State Information (CSI) is available at the receiving side of each link only. Time Division Multiplexing is assumed, where each orthogonal transmission occurs ...