Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model

For the demonstration of ultra-wideband bandwidth and pencil-beamforming, the terahertz (THz)-band has been envisioned as one of the key enabling technologies for the sixth generation networks. However, the acquisition of the THz channel entails several unique challenges such as severe path loss and...

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Main Authors: Ahmet M. Elbir, Wei Shi, Anastasios K. Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas
Format: Article
Language:English
Published: IEEE 2023-01-01
Series:IEEE Open Journal of the Communications Society
Subjects:
Online Access:https://ieeexplore.ieee.org/document/10089857/
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author Ahmet M. Elbir
Wei Shi
Anastasios K. Papazafeiropoulos
Pandelis Kourtessis
Symeon Chatzinotas
author_facet Ahmet M. Elbir
Wei Shi
Anastasios K. Papazafeiropoulos
Pandelis Kourtessis
Symeon Chatzinotas
author_sort Ahmet M. Elbir
collection DOAJ
description For the demonstration of ultra-wideband bandwidth and pencil-beamforming, the terahertz (THz)-band has been envisioned as one of the key enabling technologies for the sixth generation networks. However, the acquisition of the THz channel entails several unique challenges such as severe path loss and beam-split. Prior works usually employ ultra-massive arrays and additional hardware components comprised of time-delayers to compensate for these loses. In order to provide a cost-effective solution, this paper introduces a sparse-Bayesian-learning (SBL) technique for joint channel and beam-split estimation. Specifically, we first model the beam-split as an array perturbation inspired from array signal processing. Next, a low-complexity approach is developed by exploiting the line-of-sight-dominant feature of THz channel to reduce the computational complexity involved in the proposed SBL technique for channel estimation (SBCE). Additionally, based on federated-learning, we implement a model-free technique to the proposed model-based SBCE solution. Further to that, we examine the near-field considerations of THz channel, and introduce the range-dependent near-field beam-split. The theoretical performance bounds, i.e., Cramér-Rao lower bounds, are derived both for near- and far-field parameters, e.g., user directions, beam-split and ranges. Numerical simulations demonstrate that SBCE outperforms the existing approaches and exhibits lower hardware cost.
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spelling doaj.art-41b1493e95c5436883e55dfe007819ae2023-04-10T23:01:47ZengIEEEIEEE Open Journal of the Communications Society2644-125X2023-01-01489290710.1109/OJCOMS.2023.326362510089857Terahertz-Band Channel and Beam Split Estimation via Array Perturbation ModelAhmet M. Elbir0https://orcid.org/0000-0003-4060-3781Wei Shi1https://orcid.org/0000-0002-3071-8350Anastasios K. Papazafeiropoulos2https://orcid.org/0000-0003-1841-6461Pandelis Kourtessis3https://orcid.org/0000-0003-3392-670XSymeon Chatzinotas4https://orcid.org/0000-0001-5122-0001Interdisciplinary Centre for Security, Reliability and Trust, University of Luxembourg, Esch-sur-Alzette, LuxembourgSchool of Information Technology, Carleton University, Ottawa, ON, CanadaCommunications and Intelligent Systems Research Group, University of Hertfordshire, Hatfield, U.KCommunications and Intelligent Systems Research Group, University of Hertfordshire, Hatfield, U.KInterdisciplinary Centre for Security, Reliability and Trust, University of Luxembourg, Esch-sur-Alzette, LuxembourgFor the demonstration of ultra-wideband bandwidth and pencil-beamforming, the terahertz (THz)-band has been envisioned as one of the key enabling technologies for the sixth generation networks. However, the acquisition of the THz channel entails several unique challenges such as severe path loss and beam-split. Prior works usually employ ultra-massive arrays and additional hardware components comprised of time-delayers to compensate for these loses. In order to provide a cost-effective solution, this paper introduces a sparse-Bayesian-learning (SBL) technique for joint channel and beam-split estimation. Specifically, we first model the beam-split as an array perturbation inspired from array signal processing. Next, a low-complexity approach is developed by exploiting the line-of-sight-dominant feature of THz channel to reduce the computational complexity involved in the proposed SBL technique for channel estimation (SBCE). Additionally, based on federated-learning, we implement a model-free technique to the proposed model-based SBCE solution. Further to that, we examine the near-field considerations of THz channel, and introduce the range-dependent near-field beam-split. The theoretical performance bounds, i.e., Cramér-Rao lower bounds, are derived both for near- and far-field parameters, e.g., user directions, beam-split and ranges. Numerical simulations demonstrate that SBCE outperforms the existing approaches and exhibits lower hardware cost.https://ieeexplore.ieee.org/document/10089857/Terahertzchannel estimationbeam splitsparse Bayesian learningnear-fieldfederated learning
spellingShingle Ahmet M. Elbir
Wei Shi
Anastasios K. Papazafeiropoulos
Pandelis Kourtessis
Symeon Chatzinotas
Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
IEEE Open Journal of the Communications Society
Terahertz
channel estimation
beam split
sparse Bayesian learning
near-field
federated learning
title Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
title_full Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
title_fullStr Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
title_full_unstemmed Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
title_short Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
title_sort terahertz band channel and beam split estimation via array perturbation model
topic Terahertz
channel estimation
beam split
sparse Bayesian learning
near-field
federated learning
url https://ieeexplore.ieee.org/document/10089857/
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