South Korea's Samsung Electronics said on Monday that it has been chosen to provide next-generation communications equipment to KDDI, Japan's number two mobile phone operator.
KDDI is scheduled to start a commercial service using long-term evolution (LTE) technology next year, Samsung said in a statement without disclosing the value of the deal.
Global mobile operators are preparing to launch new technologies allowing faster wireless data transmission to cater to increasingly popular smartphones and tablets.
Samsung, the world's second largest mobile phone maker, already provides LTE equipment to wireless carriers in the US and the Middle East.
It said it is working to offer commercial LTE services to eight mobile operators around the world.
In Tokyo, KDDI said the Korean firm would provide small base stations, especially in cities. It earlier selected NEC Corp and Motorola Mobility Holdings to build the large stations for its LTE network.
Samsung said it aims to introduce the best technology "for hotspots in extremely dense user areas that require higher capacity mobile broadband, whilst simultaneously improving service quality in weak-signal areas".