LU based Beamforming schemes for MIMO systems - Inria - Institut national de recherche en sciences et technologies du numérique Access content directly
Journal Articles IEEE Transactions on Vehicular Technology Year : 2017

LU based Beamforming schemes for MIMO systems


—We present a time-domain broadband beamforming based on a Unimodular-Upper polynomial matrix decomposition. The unimodular factor is the product of elementary J-orthogonal matrices and a lower triangular matrix with ones on the diagonal, as in the constant matrix LU decomposition. This leads to a J-Orthogonal LU polynomial matrix decomposition, as a combination of two classical matrix factorization methods: Smith canonical form and LU Gaussian elimination. The inversion of the unimodular factor, for use as a pre/post filter in the beamforming scheme, is immediate and can be achieved with O(1) complexity. The resulting reduced MIMO channel is exactly diagonal, leading to separate single input single output (SISO) channels with no co-channel inteference. There is no need to model the MIMO channel as Laurent polynomial as usual, thus introducing unnecessary delays just for technical reasons. In addition, it turns out that each of the resulting SISO channels, except the last one, reduces to a simple additive noise channel, with no intersymbol interference, except for unprobable original MIMO channels. However, these very interesting features are to be balanced with the possible noise enhancement in the postfiltering step. The performance in terms of bit-error rate is studied and compared to the QR-based frequency-domain and time-domain broadband beamforming. In particular, the proposed beamforming scheme can be used both in OFDM and in single carrier MIMO systems, without cyclic prefix. Meanwhile, the QR based scheme requires a cyclic prefix extension.
Fichier principal
Vignette du fichier
revised_22Avril2016.pdf (623.22 Ko) Télécharger le fichier
Origin Files produced by the author(s)

Dates and versions

hal-01307533 , version 1 (26-04-2016)



Moustapha Mbaye, Moussa Diallo, Mamadou Mboup. LU based Beamforming schemes for MIMO systems. IEEE Transactions on Vehicular Technology, 2017, 66 (3), pp.2214-2222. ⟨10.1109/TVT.2016.2573046⟩. ⟨hal-01307533⟩
274 View
286 Download



Gmail Mastodon Facebook X LinkedIn More