1 code implementation • 18 Jan 2024 • Mohammad Farsi, Christian Häger, Magnus Karlsson, Erik Agrell
We consider the problem of recovering spatially resolved polarization information from receiver Jones matrices.
no code implementations • 26 Dec 2023 • Jinxiang Song, Vincent Lauinger, Christian Häger, Jochen Schröder, Alexandre Graell i Amat, Laurent Schmalen, Henk Wymeersch
We propose a novel frequency-domain blind equalization scheme for coherent optical communications.
1 code implementation • 15 Oct 2023 • José Miguel Mateos-Ramos, Baptiste Chatelier, Christian Häger, Musa Furkan Keskin, Luc Le Magoarou, Henk Wymeersch
Integrated sensing and communications (ISAC) is envisioned as one of the key enablers of next-generation wireless systems, offering improved hardware, spectral, and energy efficiencies.
no code implementations • 9 Jul 2023 • José Miguel Mateos-Ramos, Christian Häger, Musa Furkan Keskin, Luc Le Magoarou, Henk Wymeersch
We study model-based end-to-end learning in the context of integrated sensing and communication (ISAC) under hardware impairments.
no code implementations • 22 Feb 2023 • Jinxiang Song, Vincent Lauinger, Yibo Wu, Christian Häger, Jochen Schröder, Alexandre Graell i Amat, Laurent Schmalen, Henk Wymeersch
Furthermore, we show that for the linear channel, the proposed scheme exhibits better convergence properties than the \ac{MMSE}-based, the \ac{CMA}-based, and the \ac{VAE}-based equalizers in terms of both convergence speed and robustness to variations in training batch size and learning rate.
no code implementations • 28 Jan 2023 • Vukan Ninkovic, Dejan Vukobratovic, Christian Häger, Henk Wymeersch, Alexandre Graell i Amat
Most of today's communication systems are designed to target reliable message recovery after receiving the entire encoded message (codeword).
no code implementations • 20 Dec 2022 • José Miguel Mateos-Ramos, Christian Häger, Musa Furkan Keskin, Luc Le Magoarou, Henk Wymeersch
Integrated sensing and communication (ISAC) is envisioned to be one of the pillars of 6G.
no code implementations • 7 Dec 2022 • Keren Liu, Erik Börjeson, Christian Häger, Per Larsson-Edefors
We design and implement an adaptive machine learning equalizer that alternates multiple linear and nonlinear computational layers on an FPGA.
no code implementations • 26 Sep 2022 • Steven Rivetti, Josè Miguel Mateos-Ramos, Yibo Wu, Jinxiang Song, Musa Furkan Keskin, Vijaya Yajnanarayana, Christian Häger, Henk Wymeersch
This letter considers the problem of end-to-end learning for joint optimization of transmitter precoding and receiver processing for mmWave downlink positioning.
1 code implementation • 13 May 2022 • Christian Häger, Erik Agrell
We consider the problem of estimating an upper bound on the capacity of a memoryless channel with unknown channel law and continuous output alphabet.
no code implementations • 13 May 2022 • Mohammad Farsi, Christian Häger, Magnus Karlsson, Erik Agrell
In this paper, we analyze the effectiveness of polarization tracking algorithms in optical transmission systems suffering from fast state of polarization (SOP) rotations and polarization-dependent loss (PDL).
1 code implementation • 29 Nov 2021 • Jinxiang Song, Christian Häger, Jochen Schröder, Alexandre Graell i Amat, Henk Wymeersch
Simulation results show that the reinforcement-learning-based algorithm achieves similar performance to the standard supervised end-to-end learning approach assuming perfect channel knowledge.
no code implementations • 23 Nov 2021 • Yibo Wu, Jinxiang Song, Christian Häger, Ulf Gustavsson, Alexandre Graell i Amat, Henk Wymeersch
We propose an over-the-air digital predistortion optimization algorithm using reinforcement learning.
no code implementations • 3 Nov 2021 • José Miguel Mateos-Ramos, Jinxiang Song, Yibo Wu, Christian Häger, Musa Furkan Keskin, Vijaya Yajnanarayana, Henk Wymeersch
The approach includes the proposal of the AE architecture, a novel ISAC loss function, and the training procedure.
no code implementations • 9 Jun 2021 • Jinxiang Song, Zonglong He, Christian Häger, Magnus Karlsson, Alexandre Graell i Amat, Henk Wymeersch, Jochen Schröder
We demonstrate, for the first time, experimental over-the-fiber training of transmitter neural networks (NNs) using reinforcement learning.
no code implementations • 29 Mar 2021 • Jinxiang Song, Christian Häger, Jochen Schröder, Alexandre Graell i Amat, Henk Wymeersch
We propose an end-to-end learning-based approach for superchannel systems impaired by non-ideal hardware component.
1 code implementation • 27 Oct 2020 • Christian Häger, Henry D. Pfister
Our main observation is that the popular split-step method (SSM) for numerically solving the NLSE has essentially the same functional form as a deep multi-layer neural network; in both cases, one alternates linear steps and pointwise nonlinearities.
no code implementations • 23 Oct 2020 • Rick M. Bütler, Christian Häger, Henry D. Pfister, Gabriele Liga, Alex Alvarado
In this paper, we propose a model-based machine-learning approach for dual-polarization systems by parameterizing the split-step Fourier method for the Manakov-PMD equation.
no code implementations • 20 Jul 2020 • Vinícius Oliari, Sebastiaan Goossens, Christian Häger, Gabriele Liga, Rick M. Bütler, Menno van den Hout, Sjoerd van der Heide, Henry D. Pfister, Chigo Okonkwo, Alex Alvarado
One guiding principle for previous work on the design of practical nonlinearity compensation schemes is that fewer steps lead to better systems.
no code implementations • 19 May 2020 • Jinxiang Song, Christian Häger, Jochen Schröder, Tim O'Shea, Henk Wymeersch
End-to-end data-driven machine learning (ML) of multiple-input multiple-output (MIMO) systems has been shown to have the potential of exceeding the performance of engineered MIMO transceivers, without any a priori knowledge of communication-theoretic principles.
no code implementations • 25 Jan 2020 • Christian Häger, Henry D. Pfister, Rick M. Bütler, Gabriele Liga, Alex Alvarado
We propose a model-based machine-learning approach for polarization-multiplexed systems by parameterizing the split-step method for the Manakov-PMD equation.
no code implementations • 21 Jan 2020 • Andreas Buchberger, Christian Häger, Henry D. Pfister, Laurent Schmalen, Alexandre Graell i Amat
In this paper, we introduce a method to tailor an overcomplete parity-check matrix to (neural) BP decoding using machine learning.
no code implementations • 11 Dec 2019 • Kadir Gümüs, Alex Alvarado, Bin Chen, Christian Häger, Erik Agrell
GMI-based end-to-end learning is shown to be highly nonconvex.
1 code implementation • 11 Jun 2019 • Fabrizio Carpi, Christian Häger, Marco Martalò, Riccardo Raheli, Henry D. Pfister
In this paper, we use reinforcement learning to find effective decoding strategies for binary linear codes.
no code implementations • 22 Apr 2019 • Christian Häger, Henry D. Pfister, Rick M. Bütler, Gabriele Liga, Alex Alvarado
For the efficient compensation of fiber nonlinearity, one of the guiding principles appears to be: fewer steps are better and more efficient.
1 code implementation • 19 Apr 2019 • Jinxiang Song, Bile Peng, Christian Häger, Henk Wymeersch, Anant Sahai
A novel quantization method is proposed, which exploits the specific properties of the feedback signal and is suitable for non-stationary signal distributions.
no code implementations • 24 Jan 2019 • Mengke Lian, Fabrizio Carpi, Christian Häger, Henry D. Pfister
As an example, for the (32, 16) Reed-Muller code with a highly redundant parity-check matrix, training a PAN with soft-BER loss gives near-maximum-likelihood performance assuming simple scaling with only three parameters.
no code implementations • 22 Jan 2019 • Mengke Lian, Christian Häger, Henry D. Pfister
Rapid improvements in machine learning over the past decade are beginning to have far-reaching effects.
no code implementations • 4 Jul 2018 • Christian Häger, Henry D. Pfister
We propose a low-complexity sub-banded DSP architecture for digital backpropagation where the walk-off effect is compensated using simple delay elements.
no code implementations • 19 Jun 2018 • Christoffer Fougstedt, Christian Häger, Lars Svensson, Henry D. Pfister, Per Larsson-Edefors
We consider time-domain digital backpropagation with chromatic dispersion filters jointly optimized and quantized using machine-learning techniques.
1 code implementation • 20 Apr 2018 • Shen Li, Christian Häger, Nil Garcia, Henk Wymeersch
Machine learning is used to compute achievable information rates (AIRs) for a simplified fiber channel.
1 code implementation • 9 Apr 2018 • Christian Häger, Henry D. Pfister
For example, Ip and Kahn showed that for a 10 Gbaud signal and 2000 km optical link, a truncated SSFM with 25 steps would require 70-tap filters in each step and 100 times more operations than linear equalization.
1 code implementation • 17 Oct 2017 • Christian Häger, Henry D. Pfister
A neural-network-based approach is presented to efficiently implement digital backpropagation (DBP).