Transmit Beamforming Analysis for MIMO Systems in Indoor Residential Environment Based on 3D Ray Tracing

A Bouhlel (1) , V Guillet (1) , Ghais El Zein (2) , Gheorghe Zaharia (2)

1 Orange Labs - Orange Labs [Belfort]
2 IETR - Institut d'Électronique et des Technologies du numéRique

In this paper, an evaluation of transmit beamforming (TxBF) contribution is analyzed in the context of an indoor residential environment. Using an optimized 3D ray tracing tool, the multiple-input multiple-output (MIMO) propagation channel is simulated. The algorithm of singular value decomposition is applied and a new transmission scheme is considered. Comparisons of cases with/without TxBF are realized by analyzing the received power, the signal to noise ratio (íµí±†íµí±íµí±…) of each spatial stream and the channel capacity. It is shown that the TxBF capacity gain increases when the MIMO channel correlation at the transmit side reaches high values, especially when only the dominant eigen mode is selected. The main result concerns the antenna spacing: a judicious choice of the transmitting antenna spacing can improve the effective transmission range by more than 45% in non-line of sight (NLOS) conditions. Several MIMO configurations (number of antennas and spatial streams) are also compared to determine the relevance of a possible activation of TxBF. The interference influence is studied and it is shown that under some conditions, TxBF improves the signal to interference ratio (SIR).

Mots clés: indoor; MIMO; radio propagation; correlation; beamforming

Domaines: Electronique

A Bouhlel, V Guillet, Ghais El Zein, Gheorghe Zaharia. Transmit Beamforming Analysis for MIMO Systems in Indoor Residential Environment Based on 3D Ray Tracing. Wireless Personal Communications, 2015, 82 (1), pp.509-531. ⟨10.1007/s11277-014-2238-5⟩. ⟨hal-01100992⟩