The insatiable demand for high-speed mobile data is creating a series of pressing design challenges as today’s cellular base stations strain to handle an increasingly saturated RF spectrum. In many dense urban areas, our ability to continuously accelerate transmit and receive data speeds is under threat.
One path forward is to deploy base stations with large numbers of antennas that simultaneously communicate with multiple spatially separated user terminals over the same frequency resource and exploit multipath propagation. Often referred to as massive multiple-input, multiple-output (MIMO), this technology is also described as beamforming with a large number of antennas. But this raises the question: What is beamforming?