@inproceedings{5aac266ec1c74d66899823056ccf3c4e,
title = "Low-Complexity Dynamic Channel Estimation in Multi-Antenna Grant-Free NOMA",
abstract = "In grant-free non-orthogonal multiple access, the set of active users is unknown a priori. We address the challenging problem of dynamic channel estimation in this context. Assuming that inactive users are completely muted (in order to avoid unwanted pilot/preamble interference on active users), we investigate a channel estimation method performed jointly with user activity detection, multi-user detection and decoding. Leveraging conditional independence assumptions in probabilistic modeling, we introduce a low-complexity channel estimation performing expectation propagation in parallel for the measurements over all receive antennas. The proposed channel estimation technique is evaluated under different receive antenna correlation models and shows a good performance/complexity tradeoff with respect to joint measurement processing.",
keywords = "Dynamic channels, Gaussian approximation, NOMA, antenna correlation, expectation propagation, grant-free, loopy belief propagation, message-passing algorithms",
author = "Fakher Sagheer and Frederic Lehmann and Berthet, \{Antoine O.\}",
note = "Publisher Copyright: {\textcopyright} 2022 IEEE.; 95th IEEE Vehicular Technology Conference - Spring, VTC 2022-Spring ; Conference date: 19-06-2022 Through 22-06-2022",
year = "2022",
month = jan,
day = "1",
doi = "10.1109/VTC2022-Spring54318.2022.9860401",
language = "English",
series = "IEEE Vehicular Technology Conference",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
booktitle = "2022 IEEE 95th Vehicular Technology Conference - Spring, VTC 2022-Spring - Proceedings",
}