Wed, December 01, 2021


Major telecoms preparing array of ‘flying base stations’

Major telecommunications companies are making efforts to use “flying base stations” in the sky to send and receive the radio waves that are needed to support cell phones on the ground below.

When the Great East Japan Earthquake hit the nation 10 years ago, some base stations were damaged, and disaster-stricken areas were blacked out, making cell phones unusable over wide areas of the nation.

In the event of disasters, the flying stations are expected to cover the role normally played by base stations on the ground to provide an environment in which immediate communication is possible, thereby preventing the damage from getting worse.

Major cell phone company KDDI Corp. conducted a training session using a helicopter-borne base station in Sendai on Feb. 25.


The portable base station, weighing about 7 kilograms, was placed on a helicopter in the training session, and successfully sent radio waves from the sky.

The company hopes the base stations in the sky will allow people to communicate not only in disaster-hit areas, but also on distressed ships and in other situations. It also hopes they will be used to search for people in need of rescue by receiving signals emitted by those people’s cell phones.

“Disaster preparedness has developed over the past 10 years. We want to make it possible for people to use our services with greater peace of mind,” said Yasuo Okouchi, general manager of the Operations Division of KDDI’s Technology Sector.

In the March 2011 disaster, 29,000 base stations of major mobile operators in the Tohoku and Kanto regions were knocked out. This was more than 20% of the total of 132,000 stations in the regions.

In 2019, a power outage in Chiba Prefecture caused by a typhoon resulted in a prolonged communications disruption.

Major telecom companies are working to develop technology to ensure that communications as a lifeline will not be interrupted even in times of disaster.

An unmanned aerial vehicle with a 78-meter wingspan is being tested by HAPSMobile Inc., a subsidiary of SoftBank Corp. It can stay aloft for several months at 20 kilometers above the ground using solar cells on its wings, sending radio waves to an area of ground with a 200-kilometer diameter.

The firm calculates that 40 stations will be enough to cover all of Japan. They are expected to be put into practical use after fiscal 2023. “We can provide a communication environment for depopulated areas as well,” Ryuji Wakikawa, director of HAPSMobile, said.

Last month, NTT Docomo Inc. signed a memorandum of understanding for joint research with European aviation giant Airbus SE and Finnish telecommunications giant Nokia Oyj for similar projects.

In the aftermath of the 2016 Kumamoto earthquakes, SoftBank sent communication relay equipment aloft on a balloon.

When an earthquake hit Hokkaido in 2018, KDDI dispatched a base station aboard a ship to cover the disaster-hit area from the sea.

Such telecom giants also are developing small drones to carry flying base stations.

In June last year, the Radio Law was partially revised to allow the operation of drones for use as base stations.

“Mobile phone reception is important in our daily lives today, and it is important to keep mobile connections alive by various means,” Toyo University Prof. Isao Nakamura said.

Published : March 28, 2021

By : The Japan News