Channel coding simply explained

Four PhD students of the ICT Lab have created a video to explain the basics of channel coding in only five minutes. The concept of channel capacity and how information is transmitted are explained in the story of Alice and Bob, who are participating in a robot competition.

Shannon’s channel coding theorem is of great importance to our digital world, enabling clear access to anywhere in the world without the interruption of noise. With this video, Kaiquan Wu, Vinícius Oliari, Astrid Barreiro and Franz Lampel have created a tool to help students develop an intuition for the theorem and stimulate their interest in information theory. An earlier version of this video competed in the 2020 Student Video Exposition of the International Symposium on Information Theory.


Yunus Can Gültekin’s PhD defense: Higher data rates through smarter wireless transmission strategies

ICT Lab’s Yunus Can Gültekin has devised new types of communication strategies that greatly improve the energy efficiency of wireless transmission and result in higher data rates. On December 16, 2020, he defended his PhD thesis entitled “Enumerative Sphere Shaping Techniques for Short Blocklength Wireless Communications”.

Wireless communication systems exchange electromagnetic signals that are embedded with digital information. High data rates and low power consumption, enabled by the efficient design of these signals and the information embedding techniques, has been the key enabler for the information age and the so-called internet of things. However, the traditional design strategies have difficulty providing connectivity for an increasing number of users and satisfying the rising demand for data.

For devices to operate at the highest efficiency, they need to be transmitting their information in a way best suited to the characteristics of the communication channel. By switching from traditional strategies to these channel-aware designs, the battery life of wireless systems can be extended by more than 40 percent. In terms of data rates, this translates to hundreds of Mbit/s increase for 5G-based-communication, and even more for future wireless systems utilizing larger frequency bands.

A key element to include in wireless systems to improve transmission efficiency is the ‘signal shaping’ block. The function of this element is to convert the digital information to the transmitted wireless signals in a way adapted to the properties of the communication channel. In the PhD research of Yunus Can Gültekin, it was the objective to develop shaping blocks suitable for wireless channels. Gültekin developed algorithms that identify the most channel-friendly signals and can be implemented with low complexity at the same time.

He also developed a patented algorithm that reduces the transmit power of currently operating Wi-Fi systems by almost 30 percent and increases the data rate by around 20 percent. Moreover, this approach is compatible with existing WiFi standards, enabling a seamless transition to next-generation design strategies for WiFi-based devices. Gültekin then devised two more patented low-complexity algorithms that provide the promised increase in data rates with minimal costs. Other research carried out in the ICT Lab demonstrated that these algorithms also increase the transmission distance for conventional fiber optical systems by more than 400 km.

This research is an important step towards obtaining higher data rates in wireless and optical networks. Shaping blocks will be essential parts of future devices and communication standards, leading to faster links for many more users. With this step, communication at the maximum theoretical efficiency is looming on the horizon.

ICT Lab on ECOC 2020

From December 6 – 10th, 2020, the ICT Lab will have a strong representation at ECOC 2020, the largest conference on optical communication in Europe. This year the conference will be 100% virtual.

On December 6th, ICT Lab’s Alex Alvarado, together with Tobias Fehenberger (ADVA Optical Networking), will be hosting a workshop on constellation shaping. In this workshop, speakers from academia and industry will share their views on the future of constellation shaping and the prospects of maximizing capacity. Please check the ECOC website for further details.

Later in the week, ICT Lab researchers will be presenting three invited papers and two regular papers (including an extended paper) in various sessions. Topics include digital signal processing for quantum key distribution, end-to-end learning, nonlinearity-tolerant signal shaping, and nonlinear fiber channel models.

Presentations are pre-recorded and will be made available via the ECOC 2020 website. Twice a day, the presentations will be followed by live online Q&A sessions; please check out the schedule below for more information.

We hope to see you at ECOC 2020!


Invited Papers

Regular Papers

Lieneke Kusters’ PhD defense

On September 11, 2020, Lieneke Kusters defended her PhD thesis entitled “Helper Data Schemes for Secret-Key Binding with SRAM PUFs: Bias & Multiple Observations”. During her PhD, she studied multiple enrollment schemes, debiasing schemes, and temperature dependent behavior of SRAM PUFs. The TU/e news coverage about her work can be found on Home stretch | Fingerprint for the Internet of Things.

Photo by Bart van Overbeeke

Two invited talks at OSA Advanced Photonics Congress

Researchers Alex Alvarado and Gabriele Liga from the Information and Communication Theory Lab of Eindhoven University of Technology will have two invited talks at the upcoming meeting of the Optical Society of America from 13 – 16 July 2020.

Both researchers will present recent developments in the area of signal processing in fiber optical communications. On 13th of July, Alex Alvarado will discuss constellation shaping (geometric and probabilistic) for optical communications. On 16th of July, Gabriele Liga will give an overview of the possibilities of soft-decision aided turbo-product codes for high-speed optical transceivers. The full schedule can be viewed here.

The OSA Advanced Photonics Congress addresses the many aspects of photonic device research and development and their use in networks. This OSA Meeting will be held in an all-virtual, web conference format and participation in this online meeting is free. Check the website of the Optical Society for further info about the program and registration.

Published Paper in Nature Communications

On February 18, 2020, Nature Communications has published our paper entitled “Regular perturbation on the group-velocity dispersion parameter for nonlinear fibre-optical communications”, Nat Commun 11, 933 (2020). In this work, we look at fundamentals of optical fiber communications from a new perspective, presenting a novel mathematical model for the highly-nonlinear regime. The paper is a result from the collaboration between the Vinícius Oliari, Alex Alvarado (TU/e ICTLab), and Erik Agrell (Chalmers University of Technology in Sweden). Press release from Eindhoven University of Technology can be found here: Illuminating numerical study on light propagation in nonlinear optical fibers.

This research was funded by the projects ICONIC and FUN-NOTCH.

ICTLab in the IZS 2020

During the period of February 26—28, 2020, Yunus Gültekin presented on the 2020 International Zurich Seminar on Information and Communication (IZS 2020) his work entitled “Achievable Information Rates for Probabilistic Amplitude Shaping: A Minimum-Randomness Approach via Random Sign-Coding Arguments”, arXiv preprint arXiv:2002.10387 (2020). In this work, achievable information rates for probabilistic amplitude shaping are derived using weak typicality in order to minimize randomness in the random coding experiment.

Alex Alvarado and Frans Willems, which are co-authors in the paper, conducted an IZS invited session on “Signal-Shaping Methods”.

Invited Talk by Arie Koppelaar

On June 19, 2019, Arie Koppelaar gave an invited talk about “Challenges in Digital Radio Broadcast reception”.

A short history of radio broadcast is provided as an introduction to digital radio broadcast. A big variety in digital radio broadcast standards asks for multi-standard solutions. NXP delivers for the automotive market a Software Defined multi-standard solution such that car manufacturers can use one radio reception platform worldwide. A brief exposure is made to the digital radio standards DAB, HD-Radio, CDR and some corresponding challenges that are related to receiver implementations. The digital radio standard DRM and the implementation of its receiver are discussed in more detail, in particular the multi-stage decoding and the channel estimation method. Finally an outlook is given to the future of digital radio broadcast.

Arie G. C. Koppelaar was born in 1966. He received the Master’s degree in electrical engineering from the Eindhoven University of Technology, Eindhoven, The Netherlands, in March 1992. From 1992 to 2000, he was scientific worker at Philips Research Laboratories, Eindhoven, where he worked in the fields of error-correcting codes and digital modulation. In 2000, he joined Philips Semiconductors, Eindhoven, where he worked on baseband algorithms for IEEE802.11b and TV-on-Mobile. Since 2006, he is with NXP Semiconductors in Eindhoven and worked on Car-to-Car communications and communication for Passive Keyless Entry systems. From 2017 onwards he worked on reception algorithms for digital radio broadcast reception, in particular for Digital Radio Mondiale.

Invited Talk by Frans Willems

On July 20, 2018, Frans Willems gave an invited talk in the 2018 Munich Doctoral Seminar on Communications (MSC) entitled “Enumerative Source Coding and Shaping”.

Best Young PhD Researcher Paper award

On June 1, 2018, Yunus Can Gültekin won the Best Young PhD Researcher Paper award of the 39th WIC symposium on Information Theory in the Benelux 2018, organized by the University of Twente, held in Enschede, The Netherlands, on May 31 - June 01, 2018, with the paper entitled “On Constellation Shaping for Short Block Lengths”.

Mini-seminar: Staircase and Polar Codes

On Tuesday May 15, 2018, we had a seminar about two popular channel coding techniques: hard-decision Staircase codes and soft decision Polar codes. The performance of former one needs to be further improved and the later one has some complexity and latency issues.

The seminar speakers were:

PUF Seminar

On Tuesday March 27, 2018, Onur Günlü, TU Munich, and Boris Škorić, W/I, TU/e, presented about “Reliable Key Agreement with Biometric and Physical Identifiers Under Varying Environmental Conditions” and “Quantum security with optical PUFs”, respectively. Onur Günlü is visiting the ICTLab and is currently in the last phase of his studies.

JLT Best Paper Award

Our paper “Replacing the Soft-Decision FEC Limit Paradigm in the Design of Optical Communication Systems”, JLT vol. 33, no. 4338 (2015) has been selected as one of the two winning papers for this year’s JLT Best Paper Award. This award honors the most influential, highest-cited original paper published in JLT in 2015. Dr. Alvarado and his co-authors will be receiving the award during the Awards Ceremony at OFC 2018. More information about the award can be found on

Henk Wymeersch

On Thursday January 11, 2018, Henk Wymeersch, Chalmers University of Technology, gave a talk about “5G mmWave Localization: Single-Anchor Localization and Mapping”.

5G will be characterized by increased data rates, higher density of devices, and a wide variety of use cases. A technology to satisfy the rate requirements is mmWave, due to the large available bandwidth. As a side-effect, mmWave signals are useful for inter-device ranging. In combination with large antenna arrays, he showed how mmWave devices can perform relative localization, orientation estimation, and environment mapping. After a brief motivation of 5G localization, he described the basic signal model, followed by a Fisher information analysis, and ended with sparsity-exploiting algorithms. Finally, he highlighted connections to automotive radar and possibly synergies.

Henk Wymeersch is a Professor in Communication Systems with the Department of Electrical Engineering at Chalmers University of Technology, Sweden. He is also affiliated with the FORCE research center on fiber-optic communication, and was the PI of COOPNET, an ERC project on cooperative networks. Prior to joining Chalmers, he was a Postdoctoral Associate during 2006-2009 with the Laboratory for Information and Decision Systems (LIDS) at the Massachusetts Institute of Technology (MIT). Henk Wymeersch obtained the Ph.D. degree in Electrical Engineering/Applied sciences in 2005 from Ghent University, Belgium. He is a member of the IEEE, and served as Associate Editor for IEEE Transactions on Communications (2016-present), IEEE Transactions on Wireless Communications (2013-present), for IEEE Communication Letters (2009-2013). He served as Guest Editor for IEEE Journal on Selected Areas in Communications (JSAC, special issue on Location-aware Radios and Networks), EURASIP Journal on Wireless Communications and Networking (special issue on Localization in Mobile Wireless and Sensor Networks), and for EURASIP Journal on Advances in Signal Processing (special Issue on Signal Processing Techniques for Anywhere, anytime positioning). In 2015, he served as General Chair of the International Conference on Localization and GNSS. He has co-authored over 150 contributions in journals and international conferences, and is the author of Iterative Receiver Design (Cambridge University Press, August 2007).

Bin Chen

On Thursday May 4, 2017, Bin Chen will give a talk about “Introduction to Polar Codes”. This seminar constitutes an introduction to the main idea and structure of polar codes, which is the first provably capacity-achieving coding method. Specifically, the polarization phenomenon, polar code design, encoding structure and decoding algorithms are discussed. It will be also shown that how polar codes can achieve the capacity for infinite block length and outperform than LDPC at finite block length. Some performance results will be shown to compare polar codes with state-of-the-art codes used in the standards, such as LDPC and Turbo codes. You are cordially invited to attend this lecture which starts at 15:00 in meeting-room Flux 7.177.

Tobias Fehenberger

On Tuesday May 2, 2017, Tobias Fehenberger, Institute for Communications Engineering, Technical University of Munich (TUM) will give a lecture “On the Impact of Probabilistic Shaping on SNR and Information Rates for the Nonlinear Fiber Channel”.

Via the enhanced Gaussian noise (EGN) model, in split-step simulations, and in experiments, the effective SNR is shown to decrease due to modulation-dependent nonlinear fiber effects that are enhanced by probabilistic shaping. This SNR loss, however, is less important than the rate increase from shaping, resulting in an overall performance improvement. An optimization of the shaped distribution with the EGN model shows that optimal distributions for the AWGN channel are also an excellent choice for multi-span systems, while information rate gains are achieved for short-reach links by tailoring the input distribution specifically to this kind of channel.

Tobias Fehenberger received the Dipl.-Ing. degree in Electrical Engineering and Information Technology from the Technical University of Munich (TUM) in 2012. His diploma thesis on capacity limits of fiber-optical communication systems was carried out in collaboration with the Optical Networks Group at University College London. Mr. Fehenberger is a last-year Ph.D. student at the TUM at the TUM Institute for Communications Engineering. His research interests include coded modulation, constellation shaping, and general information-theoretic aspects of nonlinear fiber optics.

You are cordially invited to attend this lecture which starts at 14:00 in meeting-room Flux 7.177.

Alex Alvarado

On Thursday April 6, 2017, Alex Alvarado will give a talk about “Optical Fiber Communication”. This seminar constitutes an introduction to symmetrized split-step Fourier method based channel models. You are cordially invited to attend this lecture which starts at 15:00 in meeting-room Flux 7.177.

Tanya Ignatenko

On Thursday March 16, 2017, Tanya Ignatenko will give a seminar on “Biometric Security”. This lecture is an introduction to security in the context of biometrics and Slepian-Wolf coding. You are cordially invited to attend this lecture which starts at 15:00 in meeting-room Flux 7.177.

Seyran Khademi

On Thursday February 2, 2017, the ICT-LAB meetings will start with a lecture by Dr. Seyran Khademi, Fac. EEMCS, Circuit and Systems Group, TU Delft. The title of her lecture is: “Joint Precoding and PAPR Reduction in MIMO-OFDM Systems “. Seyran’s Webpage at TUDelft is here. You are cordially invited to attend this lecture which starts at 14:00 in meeting-room Flux 7.177.