A Scalable 256-Antenna Distributed MIMO Testbed with Real-Time Fully Digital Beamforming. - Dumitra Iancu; Vilgot Snygg; Sijia Cheng; Lina Tinnerberg; Mikael Henriksson; Emil Bergman; Anders J. Johansson; Baktash Behmanesh; Ove Edfors; Liang Liu 002 (CoRR, 2026)