The service, which will begin trials in Japan next month before expanding nationwide in November, aims to provide centimetre-level positioning to the autonomous tech that is beginning to be introduced across a range of industries, SoftBank said.

Japan's newly launched constellation of Michibiki satellites has been offering high-precision location data since last November, and SoftBank's service will be an early attempt at building a commercial business with it.

Despite the government backing, Japan is seen as lagging other countries in areas such as autonomous driving and the use of drones in part because of onerous legal restrictions.

Kajima Corp, one of Japan's big four construction firms, will trial the service with construction site monitoring drones. SoftBank's own SB Drive, which is developing self-driving tech for buses, will also run trials.

SoftBank is expanding its backing for the nascent field of autonomous driving on multiple fronts including Monet, a self-driving car venture set up with Toyota Motor.

SoftBank's parent SoftBank Group Corp's portfolio companies control 90% of the world's ride-hailing industry and it has taken stakes in self-driving units at Uber Technologies and General Motors Co.

Those investments come despite disappointment with speed of development in the self-driving industry, which has failed to deliver on earlier bold promises of commercial autonomous cars.

(Reporting by Sam Nussey; Editing by Rashmi Aich and Sherry Jacob-Phillips)

By Sam Nussey