Picture of Thomas Wiegart

M.Sc. Thomas Wiegart

Technical University of Munich

Chair of Communications Engineering (Prof. Kramer)

Postal address

Postal:
Theresienstr. 90
80333 München

Biography

Thomas Wiegart received the B.Sc. degree (with distinction) and the M.Sc. degree (with high distinction) in electrical engineering from Technical University of Munich (TUM) in 2015 and 2018, respectively.

He is currently working towards the doctoral degree at the TUM Institute for Communications Engineering under the supervision of Prof. Gerhard Kramer. His research interests include information theory, channel coding, probabilistic shaping, and optical communications.

Mr. Wiegart was the recipient of the Walter Gademann Price in 2016 for his Bachelor thesis, and he received an Outstanding Teaching Assistant Award from the student representatives of the Department of Electrical and Computer Engineering, TUM in 2020.
 

Teaching

Theses

Available Theses

Theses in Progress

SDM for Fiber-Optic Links with Direct Detection

Description

Two work is two-fold:

  • Physically consistent modelling of space division multiplexing (SDM) over a short-reach multimode fiber, including direct detection (DD) per mode.
  • a) Analysis of achievable rates, simple upper and lower bounds on capacity for SDM with DD.
  • b) (MIMO) Equalization for SDM with DD.

Supervisor:

Rates for Short-Reach Fiber-Optic Links with Direct Detection

Description

The topic deals with maximizing the generalized mutual information (GMI) for short-reach fiber-optic links. In particular, we are interested in jointly optimizing transmit and receive filters.

Supervisor:

Investigation of Improved Decoding for Polar Coded Shaping

Keywords:
channel coding, probabilistic shaping, polar coding

Description

Probabilistic shaping combines forward error correction and distribution matching. It allows to send encoded information with non-uniform symbol distributions. These non-uniform symbol distributions are required to achieve optimal transmission rates. One way to implement probabilistic shaping is polar coding [1], in particular Honda-Yamamoto coding [2]. For a more practical introduction to polar coding see [3].

The goal is to compare the performances of different encoding and decoding schemes for Honda-Yamamoto codes.

In this Forschungspraxis, the task is to investigate decoder performances for Honda-Yamamoto codes with different, structurally similar, decoders. The student will understand and implement successive-cancellation decoding [1] and successive-cancellation list decoding [4] for polar codes. Using these two decoders, one can directly construct encoders and decoders for Honda-Yamamoto codes for which we compare error correction capability and en-/decoding complexity under probabilistic shaping scenarios.

  [1] https://doi.org/10.1109/TIT.2009.2021379 or https://arxiv.org/abs/0807.3917

  [2] https://doi.org/10.1109/TIT.2013.2282305

  [3] https://tselab.stanford.edu/mirror/ee376a_winter1617/lectures.html

  [4] https://arxiv.org/abs/1206.0050

Prerequisites

  • Basics in Information Theory (entropy, mutual information, channel capacity)
  • Basics in Channel Coding (goal of forward error correction, linear block codes, knowledge about soft decoding algorithms is helpful)

Supervisor:

Linear Computation Coding

Description

The students task is to understand and summarize [1], which is about a new method of calculating matrix-vector products in a fast way using coding theory.

 

[1] https://arxiv.org/pdf/2102.00398.pdf

Prerequisites

Channel Coding, Information Theory

Supervisor:

Publications

2022

  • Plabst, D.; Prinz, T.; Wiegart, T.; Rahman, T.; Stojanovic, N.; Calabro, S.; Hanik, N.; Kramer, G.: Achievable Rates for Short-Reach Fiber-Optic Channels with Direct Detection. IEEE/OSA J. Lightw. Technol., 2022 more… Full text ( DOI )
  • Prinz, T.; Wiegart, T.; Plabst, D.; Rahman, T.; Hossain, S.; Stojanović, N.; Calabrò, S.; Hanik, N.; Kramer, G.: Comparison of PAM-6 Modulations for Short-Reach Fiber-Optic Links with Intensity Modulation and Direct Detection. European Conference on Optical Communication (ECOC) 2022, 2022 more… Full text ( DOI )
  • Runge, C.; Wiegart, T.; Lentner, D.; Prinz, T.: Multilevel Binary Polar-Coded Modulation Achieving the Capacity of Asymmetric Channels. IEEE International Symposium on Information Theory (ISIT), 2022Espoo, Finland more…
  • Schulte, P.; Amjad, R. A.; Wiegart, T.; Kramer, G.: Invertible low-divergence coding. IEEE Transactions on Information Theory 68 (1), 2022, 178-192 more… Full text ( DOI )
  • Wiegart, T.; Plabst, D.; Prinz, T.; Rahman, T.; Schädler, M.; Stojanović, N.; Calabrò, S.; Hanik, N.; Kramer, G.: Experiments on Bipolar Transmission with Direct Detection. European Conference on Optical Communication (ECOC) 2022, 2022 more… Full text ( DOI )

2021

  • Prinz, T.; Wiegart, T.; Plabst, D.; Calabrò, S.; Böcherer, G.; Stojanovic, N.; Rahman, T.;: PAM-6 Coded Modulation for IM/DD Channels with a Peak-Power Constraint. International Symposium on Topics in Coding (ISTC) 2021, 2021 more…
  • Wiegart, T.: Asymmetric Signalling using Polar Codes. University of California, Los Angeles (UCLA), Communications Systems Laboratory, 2021 more…
  • Wiegart, T.: Signalling for Fiber-Optic Channels with Direct Detection. Ferienakademie 2021: Advanced Topics in Information Theory and Communications, 2021 more…
  • Wiegart, T.; Da Ros, F.; Plamenov Yankov, M.; Steiner, F.; Gaiarin, S.; Wesel, R.: Probabilistically Shaped 4-PAM for Short-Reach IM/DD Links with a Peak Power Constraint. Journal of Lightwave Technology 39 (2), 2021 more… Full text ( DOI )
  • Wiegart, T.; Prinz, T.; Plabst, D.: Recovering the Phase in DD Receivers with Oversampling: A Toy Example. Huawei Joint Lab Workshop, 2021 more…

2020

  • Hellings, Christoph; Gest, Patrick; Wiegart, Thomas; Utschick, Wolfgang: Maximizing the Partial Decode-and-Forward Rate in the Gaussian MIMO Relay Channel. IEEE Transactions on Signal Processing, 2020, 1-1 more… Full text ( DOI )
  • Plabst, Daniel; García-Gómez, Francisco Javier; Wiegart, Thomas; Hanik, Norbert: Wiener Filter for Short-Reach Fiber-Optic Links. IEEE Communications Letters 24 (11), 2020, 2546 - 2550 more… Full text ( DOI )

2019

  • García-Gómez, Francisco Javier; Wiegart, Thomas: Research Activities at LNT. 2019 Workshop of the Centre of Excellence for Silicon Photonics for Optical Communications (SPOC), 2019 more…
  • Wiegart, T.: Shaping for Intensity Modulation with Direct Detection. 2019 Workshop on Coding, Cooperation, and Security in Modern Communication Networks (COCO), 2019 more…
  • Wiegart, T., Steiner, F.: Shaping for Asymmetric Channels using Polar Codes. 2019 Munich Doctoral Seminar on Communications, 2019 more…
  • Wiegart, T.; Prinz, T.; Steiner, F.; Yuan, P.: Design of Polar Codes for Parallel Channels with an Average Power Constraint. IEEE International Symposium on Information Theory, 2019 more…
  • Wiegart, T.; Steiner, F.; Schulte, P.; Yuan, P.: Shaped On-Off Keying Using Polar Codes. IEEE Communication Letters 23 (11), 2019 more… Full text ( DOI )

2018

  • Wiegart, T.; Prinz, T.; Steiner, F.; Yuan, P.: Design of Polar Codes for Parallel Channels with an Average Power Constraint. 2018 Workshop on Coding, Cooperation, and Security in Modern Communication Networks (COCO), 2018 more…
  • Wiegart, T.; Steiner, F.; Prinz, T.; Yuan, P.: Polar Code Design for Parallel Channels. Munich Doctoral Seminar on Communications 2018, 2018 more…

2016

  • Wiegart, T.; Hellings, C.; Utschick, W.: Close-to-Optimal Partial Decode-and-Forward Rate in the MIMO Relay Channel via Convex Programming. 20th International ITG Workshop on Smart Antennas (WSA 2016), 2016 more…