An Ultra-Versatile Massive MIMO Transceiver Testbed for Multi-Gb/s Communication

Massive multiple-input multiple-output (MIMO) communication has gained huge attention throughout the last years as a key technology for fifth generation mobile communication systems, because they enable wide area coverage along with ultra-high data rates and low bit energy. Furthermore, for a high number of antennas, communication theory predicts nearly optimal performance using basic linear detection and precoding schemes. However, realizing such large-scale arrays (say 100 elements or more) is non-trivial and costly and hence, only few of them are available for public research. Most often, existing solutions are limited to the current mobile communication standards. We therefore propose the design and implementation of a low-cost ultra-versatile 120-antenna massive MIMO testbed applicable both in communication and localization research. An instantaneous bandwidth of 150 MHz at a center frequency of 5.8 GHz is covered. An indoor verification measurement with 24 parallel transmissions and a bandwidth of 125 MHz achieved a sum-rate of 22.8 Gb/s with only 1.02 % bit error rate resulting in an outstanding equivalent error-free spectral efficiency of 167.2 bit/s/Hz.