Design and Demonstration of a Scalable Massive MIMO Uplink at E-Band

In this paper we present a real-time, multi-user massive MIMO hardware testbed operating in E-Band. We propose a system architecture that scales efficiently to large arrays at sampling rates associated with mm-wave bandwidths. The architecture implements two-stage beam-forming algorithms on distributed hardware, as well as per-antenna channel estimation. The features of this architecture address practical issues associated with interconnecting modular radios and steering the beams of highly directive arrays, while providing minimal hardware overhead. The hardware testbed is built with custom radio boards, off-the shelf mm-wave radio components, and FPGAs. Single and multi-user measurements are performed on the hardware to validate the effectiveness of the proposed architecture.