A Lens Array Multi-beam MIMO Testbed for Real-Time mmWave Communication and Sensing

Millimeter-wave (mmW) wireless is a promising technology for meeting the Gigabit rate and millisecond latency requirements of emerging applications. This promise fundamentally rests on the large (GHz) bandwidths and high-gain/high-dimensional beamforming possible at mmW frequencies. While multi-beam multiple input multiple output (MIMO) operation is necessary for achieving spatial multiplexing, existing systems are limited to mechanically pointed horn antennas and single-beam phased arrays of moderate sizes. In this paper, we report the development of a new testbed architecture for multi-beam MIMO communication and sensing at mmW frequencies. The testbed uses a novel lens array for multi-beamforming and data multiplexing. The paper provides a brief overview of the underlying beamspace MIMO framework, and presents initial measurement results to illustrate three key testbed functionalities: directional communication through the lens array; multiuser commmunication; and analysis of the measurement data, including channel measurements.