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.
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 • 25 Nov 2023 • Benedikt Böck, Dominik Semmler, Benedikt Fesl, Michael Baur, Wolfgang Utschick
This work introduces a novel class of positive definiteness ensuring likelihood-based estimators for Toeplitz structured covariance matrices (CMs) and their inverses.
1 code implementation • 15 Sep 2023 • Michael Baur, Nurettin Turan, Benedikt Fesl, Wolfgang Utschick
In this work, we propose to utilize a variational autoencoder (VAE) for channel estimation (CE) in underdetermined (UD) systems.
1 code implementation • 7 Sep 2023 • Benedikt Fesl, Nurettin Turan, Benedikt Böck, Wolfgang Utschick
Conditioning on the latent variable of these generative models yields a locally Gaussian channel distribution, thus enabling the application of the well-known Bussgang decomposition.
2 code implementations • 11 Jul 2023 • Michael Baur, Benedikt Fesl, Wolfgang Utschick
We propose three estimator variants that differ in their access to ground-truth data during the training and estimation phases.
no code implementations • 28 Apr 2023 • Benedikt Fesl, Nurettin Turan, Wolfgang Utschick
This work proposes a generative modeling-aided channel estimator based on mixtures of factor analyzers (MFA).
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 • 11 May 2022 • Michael Baur, Benedikt Fesl, Michael Koller, Wolfgang Utschick
First, we show that given perfectly known channel state information at the input of the VAE during estimation, which is impractical, we obtain an estimator that can serve as a benchmark result for an estimation scenario.
no code implementations • 23 Dec 2021 • Michael Koller, Benedikt Fesl, Nurettin Turan, Wolfgang Utschick
Then, a conditional mean estimator (CME) corresponding to this approximating PDF is computed in closed form and used as an approximation of the optimal CME based on the true channel PDF.