Japan’s SoftBank has introduced its 6G concept. SoftBank reports that 6G is playing a key role in its digital platform strategy, and it will support a variety of businesses as a common basic infrastructure, help AI technologies develop through the creation of “digital twins”, and make it possible to realize fully customizable communications networks and computer resources.
SoftBank started research and development of potential 6G technologies such as High Altitude Platform Stations (HAPS) and terahertz communication back in 2017. By flying base stations in the stratosphere, HAPS systems are capable of receiving and transmitting radio waves over an area stretching as far as 200km in diameter, as well as into the airspace above. As such, HAPS is expected to be a key technology for expanding communication area coverage.
SoftBank reports it has already completed a communications test in the stratosphere, led initiatives to standardize HAPS frequency bands, and established a global industry alliance. The company reports it is currently working on the terahertz range beyond millimeter-wave to applying these frequencies for telecommunications.
SoftBank plans to accommodate complete communication for customers with appropriate Service Level Agreements (SLA) in its network by leveraging Mobile Edge Computing (MEC) and network slicing. SoftBank also plans to provide services for customers by incorporating RESTful (Representational State Transfer) application programming interfaces (APIs) to customize and configure its network for customer needs.
SoftBank has been conducting technological verifications of virtual base stations equipped with GPUs since 2019. SoftBank's network will be adjusted to network traffic patterns, customer behavior and network demands automatically by AI.
SoftBank aims to offer Non-Terrestrial Network (NTN) services that use HAPS and Low Earth Orbit (LEO) and Geosynchronous Earth Orbiting (GEO) satellites. SoftBank expects this to allow it to offer internet services to more than 3 billion people around the world who are currently unable to access the web. It will also allow mobile network access at sea, in mountainous areas and the upper atmosphere, where the installation of base stations has been impossible to date.
Area expansion by HAPS
HAPSMobile, a SoftBank subsidiary, has been developing stratospheric telecommunication platform systems since 2017. In 2020, the company demonstrated a stratospheric flight and LTE communications from the stratosphere in New Mexico. Sunglider, an unmanned aircraft system equipped with solar panels, was used as the stratospheric communications platform for the test. The test proved the feasibility of SoftBank's High Altitude Platform Station (HAPS) technology. Using data obtained from the test flight, SoftBank is developing aircraft systems and wireless equipment with a view to commercialization and preparing to meet regulatory requirements.
SoftBank's R&D efforts will also focus on wireless charging/power-supply technologies for battery-powered devices such as IoT sensors, smart meters, audio headset, mouse and keyboards. SoftBank is also working on the technological verification of various systems, such as post-quantum cryptography (PQC) and quantum key distribution (QKD). By advancing these technologies, SoftBank aims to build ultra-safe networks.
SoftBank is reviewing traditional network architectures and working to build fault-resistant networks. At the same time SoftBank reports it is developing technologies that will enable networks to maintain services during anytime a failure occurs. SoftBank aims to achieve carbon-neutral operation of base stations. The company also reports that, by controlling the operation of base stations in real time in accordance with communications volume, power consumption can be minimized. SoftBank is carrying out R&D to realize carbon-free base stations.
SoftBank unveils two initiatives to develop 6G services
SoftBank has also unveiled two initiatives as specific examples of its efforts to develop 6G services.
The first one is an R&D project involving “Moving Terahertz” for smartphones. This initiative focuses on expanding frequency ranges that will enable SoftBank to provide commercial services using the terahertz band for mobile communications. The exhibit introduces a system based on the concept of moving terahertz, publicly demonstrating its application via real-time video transmission utilizing OFDM in a mobile communications system.
The second project involves SoftBank's initiatives to establish HAPS technologies, where communications equipment (a payload) that was used in a stratospheric flight test is displayed. Also on display is a cylinder antenna currently under development and a demonstration of rotating connector technology. Both technologies are essential for realizing footprint fixation technologies to control communications areas, which will be necessary to provide stable communication services with HAPS.
