Mobile phone operator SK Telecom Co. of South Korea and Tokyo-based Mobile Broadcasting Corp. signed a deal Thursday for co-ownership of a broadcast satellite that will beam digital voice signals and graphics to cell phones and other mobile devices.

It is the first satellite co-ownership deal between a Japanese and South Korean company. The satellite will be launched at the end of January, with service expected to begin in the summer.

"By sharing a satellite with the South Korean company, we can offer reasonable services to clients," Mobile Broadcasting President Tetsuya Mizoguchi told a news conference.

SK Telecom and Mobile Broadcasting will each determine the content of their own service while sharing operational responsibility for the satellite.

The satellite-based digital broadcasting service enables users to receive high-quality graphics even while traveling in trains and cars.