SoftBank Corp ran tests showing centimetre-wave spectrum in the 7GHz band, a candidate frequency for 6G, is effective for wide-area coverage and stable communication quality in dense urban environments.

The operator secured an experimental licence for the 7GHz band and started an outdoor verification trial in Tokyo’s Ginza area in June. The test used three experimental base stations supporting Massive MIMO alongside commercial 3.9GHz 5G sites, and test equipment from Nokia to evaluate the continuity of coverage, communication quality and radiowave propagation characteristics, it noted in a statement.

Using a measurement vehicle, it found strong received signal power in line-of-sight areas such as main streets, while signal reception was also achieved in non-line-of-sight areas such as narrow alleys.

It credited the results to the propagation characteristics of the 7GHz band. While diffraction into non-line-of-sight areas was limited, interference between adjacent base stations was less likely to occur, resulting in stable communication quality with minimal degradation, the statement explained.

Overall, the experiment demonstrated that 7GHz signals can provide wide-area coverage with high-quality connections when deployed as high-power macro base stations in urban commercial areas.

Akihiro Nakao, professor at the Graduate School of Engineering, The University of Tokyo, and co-chair of XG Mobile Promotion Forum, added the evaluation demonstrates the effectiveness of 6G network design using the 7GHz band. “Building on the insights gained from this verification, we will continue to promote the formation of a global 7GHz band ecosystem and its social implementation through co-creation among industry, academia, government and international partners.”