Ericsson AIR6488 B41 Massive MIMO Antenna Radio Unit This 64T64R Massive MIMO units will be likely found in Ericsson vendor territory from network vision days. It will be easily identified by it's lack of an external remote radio like Sprints typical LTE equipment and its size being significantly smaller than Sprints existing 800,1.9, and 2.5  equipment.  Source: Sprint Additional Photos from FCC Filing