Researchers in Japan successfully tested 5G communication equipment from an altitude of 4 kilometers (2.49 miles) using the 38 GHz (gigahertz) band. The experiment’s goal was to develop an aerial relay backhaul with millimeter-wave band links between ground stations and a simulated High-Altitude Platform Station (HAPS), which is a radio station aboard an uncrewed aircraft. The goal is to create high-speed and high-capacity communication for the development of 5G and 6G networks, in addition to emergency response.
The Cessna aircraft flew out of Chofu Airfield in western Tokyo with a 38 GHz 5G base station and a core network device. Such wave bands have the highest 5G data capacity, although rain and moisture can weaken the signals. Hence, an algorithm for automatically switching between multiple ground stations was successfully tested. On the other hand, three ground stations were equipped with lens antennas with automatic tracking.
“We developed technology that enables communication using 5G [New Radio] by correctly directing 38 GHz beams toward three ground stations while adapting to the flight attitude, speed, direction, position, altitude, etc. during aircraft rotation,” said Shinichi Tanaka, a manager in broadcaster SKY Perfect JSAT’s Space Business Division. “We confirmed that the onboard system, designed for the stratosphere, has adequate communication and tracking performance even under the flight speed and attitude fluctuations of a Cessna aircraft, which are more severe than those of HAPS.”
The researchers will also conduct further tests in order to commercialize a HAPS service in 2026. This consortium also includes Panasonic Holdings, apart from SKY Perfect JSAT and NTT Docomo.
