CORRECTED - CORRECTED-(OFFICIAL)-UPDATE 1-Softbank aims for 50,000 base stat

(Softbank corrects month in paragraph 2 to September from October) (Adds details, share price, background)

TOKYO, Nov 26 (Reuters) - Softbank Corp (9984.T: Quote, Profile, Research, Stock Buzz), Japan's smallest cellphone operator, aims to raise the number of its base stations to more than 50,000 next year, President Masayoshi Son told a group of reporters on Monday.

That would be at least a 6.4 percent increase from the 47,000 base stations, which connect cellphones to phone networks, that it had as of the end of September. Son did not give an investment figure.

Softbank is battling for market share with bigger rivals NTT DoCoMo Inc (9437.T: Quote, Profile, Research, Stock Buzz) and KDDI Corp (9433.T: Quote, Profile, Research, Stock Buzz), but it has fallen months behind its schedule for setting up base stations, slowing the expansion of its service area.

Still, it has outpaced both DoCoMo and KDDI in netting new sign-ups with its low-cost price plans and a marketing blitz, luring users away from DoCoMo, which controls more than half of Japan's mobile phone service market.

Shares of Softbank were up 0.8 percent at 2,420 yen at the midday break of trade, against a 1.3 percent rise in the benchmark Nikkei average .N225.

Softbank, which bought Vodafone's (VOD.L: Quote, Profile, Research, Stock Buzz) Japan unit in April last year, competes with consortiums led by DoCoMo and KDDI and also with Carlyle-controlled [CYL.UL] handy-phone firm Willcom Inc for licenses to supply high-speed Wireless Internet access.

Saddled with debt of $12 billion after the Vodafone buy, Son's firm has cut salaries and changed the way it sells handsets to avoid paying commission to retailers.

Softbank has said it would spend 387.9 billion yen in the year to March on base stations, network maintenance and related work. (Reporting by Noriyuki Hirata; Editing by Hugh Lawson)