Hybrid virtual polarimetric massive MIMO measurements at 1.35 GHz

• Published in: IET microwaves, antennas & propagation antennas & propagation, 2019-12, Vol.13 (15), p.2610-2618
• Main Authors: Challita, Frédéric, Laly, Pierre, Liénard, Martine, Tanghe, Emmeric, Joseph, Wout, Gaillot, Davy P
• Format: Article
• Language: English
• Subjects: 8 × 12 massive MIMO transmitter; antenna arrays; cross‐polarisation; different horizontal positions; different polarisation schemes; Engineering Sciences; frequency 1.35 GHz; GHz; hybrid architecture; hybrid virtual polarimetric massive MIMO measurements; indoor radio; line‐of‐sight scenario; massive MIMO systems; MIMO communication; MIMO systems; polarimetric massive multiple‐input multiple‐output radio channel; propagation channel‐based metrics; real‐time radio channel sounder; receiver orientation; receiver spatial correlation; Rician channels; signal; Special Section: Metrology for 5G Technologies; sum‐rate capacity; system‐oriented metrics; uniform rectangular array; vertical uniform linear array; virtual array; wireless channels; yet realistic array
• ISSN: 1751-8725; 1751-8733; 1751-8733
• DOI: 10.1049/iet-map.2018.6120

The polarimetric massive multiple-input multiple-output (MIMO) radio channel of an indoor line-of-sight scenario is investigated at 1.35 GHz using a real-time radio channel sounder. The 8 × 12 massive MIMO transmitter is constructed using a hybrid architecture including a vertical uniform linear array translated at different horizontal positions forming a virtual, yet realistic, uniform rectangular array. The performance of the system is evaluated with six users distributed in the room for different polarisation schemes and receiver orientations using propagation channel-based metrics (such as receiver spatial correlation and Rician factor) and system-oriented metrics such as sum-rate capacity and signal to interference and noise ratio. The results show a clear dependence of the performance to the polarisation schemes and receiver orientation and showing that when facing the array, cross-polarisation can be very beneficial. Furthermore, it is concluded that the additional degree of freedom brought by the polarisation diversity can contribute to improve spectral efficiency (∼20% depending on the configuration), paving the way for further capacity enhancements in massive MIMO systems. It was also found that the receiver spatial correlation can be modelled using a Burr distribution.