Sources say major Japanese mobile phone carrier KDDI is working with US venture firm SpaceX to launch a satellite communications service as early as next year.
KDDI's 4G mobile network currently covers most areas where people live. The Japanese firm will use SpaceX's satellites in the aim of improving services in mountainous areas and remote islands.
SpaceX's satellites fly lower than other types, enabling high-speed, large-capacity communications. KDDI also plans to consider using them during disasters.
The two companies have already started trials of the service.
Japanese telecom firms SoftBank and Rakuten Mobile, as well as US IT giant Amazon, have also announced plans for high-speed internet communications using satellites.
SpaceX was founded by Elon Musk, the CEO of electric vehicle maker Tesla.