no code implementations • 26 Mar 2024 • Nurettin Turan, Benedikt Fesl, Benedikt Böck, Michael Joham, Wolfgang Utschick
Once shared with the mobile terminal (MT), the GMM is utilized to determine a feedback index at the MT in the online phase.
no code implementations • 21 Mar 2024 • Donia Ben Amor, Michael Joham, Wolfgang Utschick
In this work, we develop an efficient precoding strategy for a multi-user multiple-input-single output (MU MISO) system operating in frequency-division-duplex (FDD) mode, where rate splitting multiple access (RSMA) is implemented.
1 code implementation • 6 Mar 2024 • Benedikt Fesl, Michael Baur, Florian Strasser, Michael Joham, Wolfgang Utschick
This work proposes a novel channel estimator based on diffusion models (DMs), one of the currently top-rated generative models.
1 code implementation • 5 Mar 2024 • Benedikt Fesl, Benedikt Böck, Florian Strasser, Michael Baur, Michael Joham, Wolfgang Utschick
Diffusion probabilistic models (DPMs) have recently shown great potential for denoising tasks.
no code implementations • 13 Feb 2024 • Nurettin Turan, Benedikt Böck, Kai Jie Chan, Benedikt Fesl, Friedrich Burmeister, Michael Joham, Gerhard Fettweis, Wolfgang Utschick
In this work, we utilize a Gaussian mixture model (GMM) to capture the underlying probability density function (PDF) of the channel trajectories of moving mobile terminals (MTs) within the coverage area of a base station (BS) in an offline phase.
no code implementations • 4 Dec 2023 • Donia Ben Amor, Michael Joham, Wolfgang Utschick
In this work, we derive a lower bound on the training-based achievable downlink (DL) sum rate (SR) of a multi-user multiple-input-single-output (MISO) system operating in frequency-division-duplex (FDD) mode.
no code implementations • 8 Sep 2023 • Sadaf Syed, Dominik Semmler, Donia Ben Amor, Michael Joham, Wolfgang Utschick
Reconfigurable intelligent surface (RIS) is considered a prospective technology for beyond fifth-generation (5G) networks to improve the spectral and energy efficiency at a low cost.
no code implementations • 23 Aug 2023 • Josef A. Nossek, Dominik Semmler, Michael Joham, Wolfgang Utschick
The vast majority of research publications on RIS are focussing on system-level optimization and are based on very simplistic models ignoring basic physical laws.
no code implementations • 1 Feb 2023 • Valentina Rizzello, Benedikt Böck, Michael Joham, Wolfgang Utschick
This work aims to predict channels in wireless communication systems based on noisy observations, utilizing sequence-to-sequence models with attention (Seq2Seq-attn) and transformer models.
no code implementations • 20 Jan 2023 • Donia Ben Amor, Michael Joham, Wolfgang Utschick
Although the LMMSE channel estimate exhibits a better quality in terms of the MSE due to the exploitation of the channel statistics, we show that in the case of contaminated channel observations, zero-forcing based on the LMMSE is unable to eliminate the inter-user interference in the asymptotic limit of high DL transmit powers.
no code implementations • 16 Jan 2023 • Benedikt Fesl, Nurettin Turan, Michael Joham, Wolfgang Utschick
In this letter, we propose a Gaussian mixture model (GMM)-based channel estimator which is learned on imperfect training data, i. e., the training data are solely comprised of noisy and sparsely allocated pilot observations.
no code implementations • 14 Nov 2022 • Benedikt Fesl, Andreas Faika, Nurettin Turan, Michael Joham, Wolfgang Utschick
In order to illuminate the additional cascaded channel as compared to systems without a RIS, commonly an unaffordable amount of pilot sequences has to be transmitted over different phase allocations at the RIS.
no code implementations • 13 Jul 2022 • Valentina Rizzello, Matteo Nerini, Michael Joham, Bruno Clerckx, Wolfgang Utschick
In this work, we propose an efficient method for channel state information (CSI) adaptive quantization and feedback in frequency division duplexing (FDD) systems.
no code implementations • 17 Jan 2022 • Donia Ben Amor, Michael Joham, Wolfgang Utschick
In this work, we present new results for the application of rate splitting multiple access (RSMA) to the downlink (DL) of a massive multiple-input-multiple-output (MaMIMO) system operating in frequency-division-duplex (FDD) mode.