NTT DOCOMO said its 5G test has achieved 5.5 Gbps throughput communicating to eight mobile terminals. This is a world’s first.

The telecom operator has conducted 5G transmission of a 4.5GHz signal using beamforming and inter-base station coordination to reduce interference during the 5G test in Japan.

NEC said the 5G test, conducted in Kawasaki, Japan from May 9 to 11, used digital signal processing between base stations equipped with signal processing units and massive-element antennas to coordinate beamforming between base stations — communicating with 8 mobile terminals.

The 5G test verified the feasibility of beam forming through coordination of small, optical-feeder-type base stations equipped with 128-element antennas and digital signal processing units, which were connected via optical fiber.

NEC, which is coordinating for the 5G test, said antennas of adjacent base stations cause large interference and reduce data rate. NTT DOCOMO conducted the 5G test using  beamforming and digital signal processing to mutually cancel out interference. The solution will enable telecom engineers to install multiple antennas more flexibly for higher-capacity 5G communications in dense urban areas.