The trial across eight base stations used beamforming with inter-base station coordination between two base stations. This coordination was achieved with signal processors and massive-element antennas through digital signal processing.
The 5.5GHz speeds were achieved by utilizing beamforming through small base stations in an optical feeder structure to connect antennas with a total of 128 elements, with signal processing conducted via optical fiber.
Beam control and digital signal processing were used to mutually cancel out the signal interference associated with the use of antennas in two different places.
NEC said this beam control more flexibly enables the installation of multiple antennas, and is expected to usher in higher-capacity communications even in areas with high population density.