Open AccessGram–Schmidt orthogonalisation aided hybrid precoding in millimetre‐wave massive MIMO systems
Author(s) -
Zhan Jinlong,
Dong Xiaodai,
Huo Yiming,
Zhang Yu
Publication year - 2020
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2018.6090
Subject(s) - precoding , matching pursuit , orthogonality , mimo , algorithm , computer science , spectral efficiency , mathematics , matrix (chemical analysis) , control theory (sociology) , telecommunications , artificial intelligence , beamforming , compressed sensing , materials science , geometry , control (management) , composite material
The authors introduce a novel hybrid precoding algorithm based on Gram–Schmidt orthogonalisation (GSO) in millimetre‐wave massive MIMO systems. Specifically, the columns of array response matrix orthogonalised by the GSO process are considered as a set of candidate analogue precoders, then traditional orthogonal matching pursuit (OMP) is utilised to find the optimal analogue and digital precoders. Since GSO is a recursive process that depends on the order in which the matrix columns are selected. A heuristic solution to the order of columns selection is suggested according to the array response vector along which the fully‐digital precoder has the maximum projection. The proposed algorithm, not only constrained to uniform linear arrays, can avoid the matrix inversion in designing the digital precoder compared to OMP. Simulation results show that the spectral efficiency and bit error rate of the proposed hybrid precoding solutions are close to that obtained with fully digital architectures. Furthermore, the results indicate that the proposed hybrid precoding solutions outperform the orthogonality‐based matching pursuit, which uses the columns of the DFT matrix as a set of candidate analogue precoders.