An Experimental Study of Massive MIMO Properties in 5G Scenarios

Three main characteristics of massive multiple-input-multiple-output (MIMO) are studied. The widespread use of these characteristics and their lack of validation motivates this paper based in measurements. First, we study the channel hardening when the number of antennas in the base station (BS) increases. Second, we focus on the channel vector orthogonality between two users. Third, we investigate the rank of the spatial covariance matrix. The data used for this paper have been obtained in two measurement campaigns with all real antennas (i.e., neither virtual arrays nor virtual users). The first one has 64 BS elements arranged in 3 configurations, and it serves 8 users with 2 antennas each. The second campaign has 128 BS elements, serving 2 users with 2 antennas each. Both campaigns include line-of-sight and nonline-of-sight scenarios, designed according to the future 5G deployment scenarios. We show the rate of channel hardening when the number of BS elements increases. We evaluate the sum rate of two users at specific distances between them. We observe the large angular spread occupied by the user.

[1]  Fredrik Tufvesson,et al.  Measured propagation characteristics for very-large MIMO at 2.6 GHz , 2012, 2012 Conference Record of the Forty Sixth Asilomar Conference on Signals, Systems and Computers (ASILOMAR).

[2]  Bo Ai,et al.  Massive MIMO channel measurements and analysis at 3.33 GHz , 2015, 2015 10th International Conference on Communications and Networking in China (ChinaCom).

[3]  Thomas L. Marzetta,et al.  Noncooperative Cellular Wireless with Unlimited Numbers of Base Station Antennas , 2010, IEEE Transactions on Wireless Communications.

[4]  Stephan ten Brink,et al.  Channel measurements for large antenna arrays , 2012, 2012 International Symposium on Wireless Communication Systems (ISWCS).

[5]  Thomas L. Marzetta,et al.  Multiple-antenna channel hardening and its implications for rate feedback and scheduling , 2004, IEEE Transactions on Information Theory.

[6]  Jun Sun,et al.  The Impact of Physical Channel on Performance of Subspace-Based Channel Estimation in Massive MIMO Systems , 2015, IEEE Transactions on Wireless Communications.

[7]  Bo Ai,et al.  Measurement-Based Characterizations of Indoor Massive MIMO Channels at 2 GHz, 4 GHz, and 6 GHz Frequency Bands , 2016, 2016 IEEE 83rd Vehicular Technology Conference (VTC Spring).

[8]  Elisabeth de Carvalho,et al.  Frequency Dependence of Measured Massive MIMO Channel Properties , 2016, 2016 IEEE 83rd Vehicular Technology Conference (VTC Spring).

[9]  Giuseppe Caire,et al.  Joint Spatial Division and Multiplexing—The Large-Scale Array Regime , 2013, IEEE Transactions on Information Theory.

[10]  Satoshi Suyama,et al.  5G Mobile and Wireless Communications Technology , 2016 .

[11]  Giuseppe Caire,et al.  Joint Spatial Division and Multiplexing—The Large-Scale Array Regime , 2012, IEEE Transactions on Information Theory.

[12]  Fredrik Tufvesson,et al.  Linear Pre-Coding Performance in Measured Very-Large MIMO Channels , 2011, 2011 IEEE Vehicular Technology Conference (VTC Fall).

[13]  Liu Liu,et al.  Channel measurements and angle estimation for massive MIMO systems in a stadium , 2015, 2015 17th International Conference on Advanced Communication Technology (ICACT).

[14]  Elisabeth de Carvalho,et al.  Towards very large aperture massive MIMO: A measurement based study , 2014, 2014 IEEE Globecom Workshops (GC Wkshps).

[15]  Jiajing Chen,et al.  Measurement-based massive MIMO channel modeling in 13–17 GHz for indoor hall scenarios , 2016, 2016 IEEE International Conference on Communications (ICC).

[16]  Hao Yu,et al.  The rationality analysis of massive MIMO virtual measurement at 3.5 GHz , 2016, 2016 IEEE/CIC International Conference on Communications in China (ICCC Workshops).

[17]  Fredrik Tufvesson,et al.  Massive MIMO Performance Evaluation Based on Measured Propagation Data , 2014, IEEE Transactions on Wireless Communications.

[18]  F. Tufvesson,et al.  Channel measurements and analysis for very large array systems at 2.6 GHz , 2012, 2012 6th European Conference on Antennas and Propagation (EUCAP).

[19]  Fredrik Tufvesson,et al.  Spatial separation of closely-spaced users in measured massive multi-user MIMO channels , 2015, 2015 IEEE International Conference on Communications (ICC).

[20]  Elisabeth de Carvalho,et al.  Massive MIMO properties based on measured channels: Channel hardening, user decorrelation and channel sparsity , 2016, 2016 50th Asilomar Conference on Signals, Systems and Computers.