UCL logo

UCL Discovery

UCL home » Library Services » Electronic resources » UCL Discovery

A Closed-Form Expression to Evaluate Nonlinear Interference in Raman-Amplified Links

Semrau, D; Saavedra, G; Lavery, D; Killey, RI; Bayvel, P; (2017) A Closed-Form Expression to Evaluate Nonlinear Interference in Raman-Amplified Links. Journal of Lightwave Technology , 35 (19) pp. 4316-4328. 10.1109/JLT.2017.2741439. Green open access

08013018.pdf - ["content_typename_Published version" not defined]

Download (841kB) | Preview


An accurate, closed-form expression to evaluate the nonlinear interference (NLI) noise power in Nyquist-spaced, coherent optical communication systems using backward-pumped Raman amplification is presented. This enables rapid estimation of the signal-to-noise ratio (SNR) and avoids the need of integral evaluations and split-step simulations. The accuracy of the proposed formula is compared to numerical integration of the Gaussian noise (GN) model and split-step simulations over a wide range of parameters, including three different fiber types. Additionally, the impact of pump depletion on the NLI noise power is studied and the formula is applied to a second-order Raman-amplified system. In the case of first-order amplification and negligible pump depletion, a maximum deviation of 0.34 dB in NLI coefficient between the GN model and the closed-form formula is found which corresponds to a maximum deviation of 0.1 dB in optimal SNR or similar figures of merit (e.g., maximum reach). When pump depletion is considered, it is shown that the NLI coefficient becomes a function of launch power and as a result the cubic power dependence of the NLI noise power is no longer valid in such regimes. Finally, for the second-order Raman-amplified system, a maximum deviation of 0.39 dB in NLI coefficient is reported.

Type: Article
Title: A Closed-Form Expression to Evaluate Nonlinear Interference in Raman-Amplified Links
Open access status: An open access version is available from UCL Discovery
DOI: 10.1109/JLT.2017.2741439
Publisher version: http://dx.doi.org/10.1109/JLT.2017.2741439
Language: English
Additional information: This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/
Keywords: Interference, Closed-form solutions, Signal to noise ratio, Numerical models, Stimulated emission, Dispersion, Attenuation, Channel model, Gaussian noise model, nonlinear distortion, nonlinear interference, optical fiber communications, Raman amplification
URI: http://discovery.ucl.ac.uk/id/eprint/1573262
Downloads since deposit
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item