Increasing the Capacity of Optical NonlInear Channels (1PhD and 1 PostDoc) (V36.3003)

Increasing the Capacity of Optical NonlInear Channels (1PhD and 1 PostDoc)

PhD-student, (Post-doctoral) Researcher
Department of Electrical Engineering
Date off
Reference number

Job description

ICONIC: Increasing the Capacity of Optical NonlInear Channels (1PhD position 1 PostDoc Position) 

Optical fibres underpin our global information society and has experienced an astonishing evolution over the past four decades. Currently deployed commercial systems based on single-mode fibres can transmit data rates in excess of 10 Tb/s per fibre. Widely deployed for the global communications infrastructure, single-mode fibres currently carry more than 99% of the global Internet traffic and are a key component in the backbone networks for mobile telephony and the Internet. The continuation of this dramatic throughput growth has become constrained due to a power dependent nonlinear distortion in single mode fibres arising from a phenomenon known as the Kerr effect. The action of this nonlinear effect in combination with dispersion and noise is modelled using a stochastic partial nonlinear differential equation known as the Nonlinear Schrödinger Equation (NLSE). This will be the starting point for this project. 

The ICONIC Project
In this project, we will answer different questions regarding information transmission through optical fibres. For example, what is the maximum amount of information that can be reliably transported by optical fibres? or how to design coded modulation systems that approach this limit? To answer these questions, we will first develop accurate channel models for the nonlinear optical channel in the high-power regime. Novel coded modulation transceivers tailored to the nonlinear optical channel will then be designed. Techniques that will be considered in this project include (but not limited to): 

  • signal (constellation) shaping: geometrical and probabilistic shaping,
  • error control coding (FEC), coded modulation, and maximum likelihood detection,
  • asymptotic analysis and mismatched decoding theory,
  • nonlinear compensation techniques: digital back-propagation, Volterra equalisers, etc., and
  • novel signaling techniques: nonlinear Fourier transform and eigenvalue communications. 

Academic and Research Environment
Eindhoven University of Technology (TU/e) is one of Europe’s top technological universities, situated in the heart of one of Europe’s largest high-tech innovation ecosystems. Research at TU/e is characterized by a combination of academic excellence and a strong real-world impact. This impact is often obtained via close collaboration with high-tech industries. This exciting PhD project will be carried out at the signal processing systems (SPS) group but in close collaboration with the electro-optical communications (ECO) group as well as with industrial partners both groups collaborate with. The positions will include international short- and medium-term research visits to academic or industrial research institutions.

Job requirements

We are hiring 1 PhD student fully funded for 4 years and 1 Postdoctoral Researcher fully funded for up to 3 years. Both candidates must be able bridge the distance between advanced fundamental concepts and theories on the one hand, and practical implementation and evaluation of these concepts on the other hand. They should be able to think out of the box, distinguish main lines from details, and provide structure to their work, have excellent multidisciplinary team working and communication skills, and be fluent in English. 

PhD Position: PhD candidates must have a strong MSc degree in signal processing, communications, information theory, or a related discipline. Some affinity with optical communications is beneficial but not mandatory, although experience with the NLSE is desirable. Candidates with a degree in applied mathematics or nonlinear physics are also welcome to apply.

Postdoc Position: For the postdoc position, candidates should have a Ph.D. degree in Electrical Engineering, Computer Science, Applied Mathematics, Nonlinear Physics, or related areas. The candidate should have demonstrated research experience in at least one of the areas described above. Experience with channel modeling and/or nonlinear Fourier transform is particularly desirable.

Conditions of employment

  • A challenging job in a dynamic and ambitious university
  • Full-time temporary appointment for 4 years for the PhD position and for 3 years for the PostDoc position
  • A gross salary per month of € 2222,- (first year) as a PhD up to € 2840,- (final year).
    A gross salary per month between € 3111,- and € 4084,- per month is offered for the PostDoc position, depending on knowledge and experience (based on salary scale 10 of CAO Dutch Universities)
  • TU/e offers moreover an excellent package of fringe benefits (annual holiday allowance and end of year allowance, excellent technical infrastructure, the possibility of child care, reimbursement for moving costs, excellent sports facilities, and assistance in finding accommodation)

Information and application


  • For more information about the project and any informal enquiries, please contact dr. Alex Alvarado, Assistant Professor (
  • For information concerning employment conditions you can contact Mrs. Tanja van Waterschoot, HR officer (
  • More information on employment conditions can be found at .
  • Application

    If interested, please upload a detailed curriculum vitae, a letter of motivation and portfolio with relevant work by the button "apply now" at the top of  this page.

    Please keep in mind; you can upload only 5 documents up to 2 MB each.

Related Publications:

  • L. Beygi, E. Agrell, J. M. Kahn, and M. Karlsson, “Coded modulation for fiber-optic networks: Toward better tradeoff between signal processing complexity and optical transparent reach,” IEEE Signal Processing Magazine, vol. 31, no. 2, pp. 93–103, Mar. 2014.
  • R. Dar, M. Shtaif, and M. Feder, “New bounds on the capacity of the nonlinear fiber-optic channel,” Optics Letter, vol. 39, no. 2, pp. 398–401, Jan. 2014.
  • A. Alvarado, F. Brännström, E. Agrell, and T. Koch, “High-SNR asymptotics of mutual information for discrete constellations with applications to BICM,” IEEE Trans. Inf. Theory, vol. 60, no. 2, pp. 1061–1076, Feb. 2014.
  • A. Alvarado, E. Agrell, D. Lavery, R. Maher, and P. Bayvel, “Replacing 
the soft-decision FEC limit paradigm in the design of optical communication systems,” Journal of Lightwave Technology, vol. 33, no. 20, pp. 4338–4352, Oct. 2015. 

  • G. Kramer, M. I. Yousefi, and F. R. Kschischang, “Upper bound on the capacity of a cascade of nonlinear and noisy channels,” in Information Theory Workshop (ITW), 2015.
  • R. Maher, T. Xu, L. Galdino, M. Sato, A. Alvarado, K. Shi, S. J. Savory, B. C. Thomsen, R. I. Killey and P. Bayvel, “Spectrally Shaped DP-16QAM Super-Channel Transmission with Multi-Channel Digital Back Propagation,” ScientificReports 5, 8214, 2015.
  • L. Szczecinski and A. Alvarado, Bit-Interleaved Coded Modulation: Fundamentals, Analysis and Design. Chichester, UK: John Wiley & Sons, 2015.

  • A. Alvarado and E. Agrell, “Four-dimensional coded modulation with bit-wise decoders for future optical communications,” Journal of Lightwave Technology, vol. 33, no. 10, pp. 1993–2003, May 2015.
  • T. Fehenberger, A. Alvarado, P. Bayvel, and N. Hanik, “On achievable rates for long-haul fiber-optic communications,” Opt. Express, vol. 23, no. 7, pp. 9183–9191, Apr. 2015.
  • G. Liga, A. Alvarado, E. Agrell, and P. Bayvel, “Information rates of next-generation long-haul optical fiber systems using coded modulation,” Journal of Lightwave Technology, vol. 35, no. 1, pp. 113–123, 2017.