SK Telecom Co. won the auction for the "golden" spectrum 1.8 GHz band for its super-fast wireless service, the country's telecom regulator said Monday, setting the stage for the nation's leading mobile operator to better compete with its smaller rivals in the lucrative market for smartphones. SK Telecom bought the spectrum band for 995 billion won (US$920 million). It is widely used for the super-fast wireless service using the fourth-generation mobile technology called long term evolution (LTE). The spectrum auction ran for an eighth day on Friday, nearly doubling the initial bid price of 446 billion won. KT Corp., the second-largest mobile carrier, said it decided to drop out of the bidding race due to soaring biding costs. Instead, it won the license for the remaining 800 MHz band for 261 billion won. SK Telecom launched LTE services in Seoul in July, and KT is also poised to begin the services in November. Of the two other spectrum bands up for sale, LG Uplus Corp., the country's smallest mobile operator, won the license for the 2.1 GHz band for 445.5 billion won. The number of smartphone users in South Korea, one of the world's most-wired nations, stood at 15 million in July, according to government data. The figure is expected to hit 20 million by the end of this year, accounting for about 40 percent of the overall wireless market. Some watchers said the high spectrum prices are feared to hurt the profitability of the mobile carriers, which are already struggling with mobile tariff cuts. SK Telecom and KT joined government efforts to tame inflation in Asia's fourth-largest economy by cutting their rates. Shares of SK Telecom were trading at 149,000 won on the Seoul bourse as of 11:10 a.m., up 3.11 percent.