NTT says it is pushing on with real world 5G tests
NTT DOCOMO has released a few details of trials of 5G enabling technology it has been carrying out in real world environments.
The two most recent trials it announced, taking place in October and November, were:
A mmWave (70GHz) trial it conducted with Nokia Networks at a high-rise complex in Tokyo, achieving ultra-high-speed data transmission in excess of 2Gbps. The opeator said that it was the first 5G data transmission in a commercial complex, such as a shopping mall, due to problems with base stations being out of line of sight and diffused reflections causing the attenuation of highly directional millimeter signals. This time, however, the trial was successful thanks to the use of two new technologies: beamforming, which focuses radio waves in a specific direction, and beam tracking to control beam direction according to the mobile device’s location.
A trial with Samsung Electronics in Suwon-city, South Korea where a maximum data-receiving speed of more than 2.5Gbps was achieved in a vehicle travelling with a speed of 60km/h. The trial used a 28GHz high-frequency signal in combination with beamforming with a high number of antenna elements and beam tracking.
Other trials conducted recently by DOCOMO in collaboration with vendors include:
DOCOMO and Ericsson verifying the feasibility of massive MIMO technology by achieving a real-time data-receiving speed of more than 10Gbps using Ericsson 5G radio prototypes with a 15GHz frequency band on November 19.
DOCOMO and Fujitsu confirming a multi-base-station cooperative transmission system by achieving a data-receiving speed of over 11Gbps in total of four mobile devices with a 4.6GHz signal on October 26.
And finally in November an outdoor data transmission trial conducted by DOCOMO, DOCOMO Beijing Communications Laboratories and Huawei Technologies using a multi-user MIMO (MU-MIMO) transmission of 43.9bps/Hz/cell, which was 3.6-times more efficient than past outdoor trials of LTE-Advanced based MU-MIMO technology.