Exploiting Spatial Correlation for Pilot Reuse in Single-Cell mMTC

Loading...
Thumbnail Image

Access rights

openAccess
acceptedVersion

URL

Journal Title

Journal ISSN

Volume Title

A4 Artikkeli konferenssijulkaisussa

Major/Subject

Mcode

Degree programme

Language

en

Pages

6

Series

Proceedings of the IEEE 32nd Annual International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2021, pp. 654-659, IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications workshops

Abstract

As a key enabler for massive machine-type communications (mMTC), spatial multiplexing relies on massive multiple-input multiple-output (mMIMO) technology to serve the massive number of user equipments (UEs). To exploit spatial multiplexing, accurate channel estimation through pilot signals is needed. In mMTC systems, it is impractical to allocate a unique orthogonal pilot sequence to each UE as it would require too long pilot sequences, degrading the spectral efficiency. This work addresses the design of channel features from correlated fading channels to assist the pilot assignment in multi-sector mMTC systems under pilot reuse of orthogonal sequences. In order to reduce pilot collisions and to enable pilot reuse, we propose to extract features from the channel covariance matrices that reflect the level of orthogonality between the UEs channels. Two features are investigated: covariance matrix distance (CMD) feature and CMD-aided channel charting (CC) feature. In terms of symbol error rate and achievable rate, the CC-based feature shows superior performance than the CMD-based feature and baseline pilot assignment algorithms.

Description

Keywords

Other note

Citation

Ribeiro, L, Leinonen, M, Al-Tous, H, Tirkkonen, O & Juntti, M 2021, Exploiting Spatial Correlation for Pilot Reuse in Single-Cell mMTC. in Proceedings of the IEEE 32nd Annual International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2021. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications workshops, IEEE, pp. 654-659, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, Helsinki, Finland, 13/09/2021. https://doi.org/10.1109/PIMRC50174.2021.9569562