Channel Estimation for Distributed Intelligent Reflecting Surfaces Assisted Multi-User MISO Systems

Hibatallah Alwazani, Qurrat-Ul-Ain Nadeem, Anas Chaaban

Research output: Chapter in Book/Report/Conference proceedingConference contribution

15 Scopus citations


Intelligent reflecting surfaces (IRSs)-assisted wireless communication promises improved system performance, while posing new challenges in channel estimation (CE) due to the passive nature of the reflecting elements. Although a few CE protocols for IRS-assisted multiple-input single-output (MISO) systems have appeared, they either require long channel training times or are developed under channel sparsity assumptions. Moreover, existing works focus on a single IRS, whereas in practice multiple such surfaces should be installed to truly benefit from the concept of reconfiguring propagation environments. In light of these challenges, this paper tackles the CE problem for the distributed IRSs-assisted multi-user MISO system. An optimal CE protocol requiring relatively low training overhead is developed using Bayesian techniques under the practical assumption that the BS-IRSs channels are dominated by the line-of-sight (LoS) components. An optimal solution for the phase shifts vectors required at all IRSs during CE is determined and the minimum mean square error (MMSE) estimates of the BSusers direct channels and the IRSs-users channels are derived. Simulation results corroborate the normalized MSE (NMSE) analysis and establish the advantage of the proposed protocol as compared to benchmark scheme in terms of training overhead.
Original languageEnglish (US)
Title of host publication2020 IEEE Globecom Workshops (GC Wkshps
ISBN (Print)9781728173078
StatePublished - Dec 2020
Externally publishedYes

Bibliographical note

KAUST Repository Item: Exported on 2021-03-29
Acknowledged KAUST grant number(s): OSR-2018-CRG7-3734
Acknowledgements: This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) under Award No. OSR-2018-CRG7-3734
This publication acknowledges KAUST support, but has no KAUST affiliated authors.


Dive into the research topics of 'Channel Estimation for Distributed Intelligent Reflecting Surfaces Assisted Multi-User MISO Systems'. Together they form a unique fingerprint.

Cite this