The First Real-Time Testbed for Massive MIMO from Lund University

Another great job in Massive MIMO studies, they built a Massive MIMO system which includes 100 BS antennas and 50 FPGAs.
Massive MIMO system - image from the paper:
 The World’s First Real-Time Testbed for Massive MIMO: Design, Implementation, and Validation


You can find this paper in following link @axiv.org: https://arxiv.org/pdf/1701.01161.pdf