Advanced Info Service (AIS) will officially launch its third-generation (3G) commercial service on the 2100-megahertz frequency in April, one month ahead of schedule, in a bid to compete for market supremacy.
The country's largest mobile operator aims to maintain its leadership of the cellular market by becoming more competitive in the 3G market, where its smaller rival True Move leads the way.
The move by AIS is in response to third-ranked True Move's recent announcement that it will launch a 4G service with 300 sites next month.
True Move has three million subscribers using the 850-MHz bandwidth for its 3G service.
Customers using 2G and 3G services on the 2G frequencies for AIS and Total Access Communication networks are facing network congestion as demand for mobile data services explodes in tandem with the proliferation of smartphones and tablets.
"We need to speed up our 3G service roll-out with a nationwide network to reduce possible setbacks," said Wichian Mektrakarn, AIS's chief executive, said AIS plans to have 20,000 3G base stations on the 2.1-GHz bandwidth.
AIS has 14,000 3G base stations running on the 900-MHz frequency and thousands of bases on 3G HSPA technology on the 900-MHz band.
Digital Phone Co (DPC), AIS's subsidiary operating mobile services on the 1800-MHz band, has 4,000 base stations on 2G technology.
However, the concessions of DPC and True Move are due to expire in September under agreements with state-owned CAT Telecom.
By law, the spectrum must be returned to the National Broadcasting and Telecommunications Commission (NBTC) to be reallocated once the concessions expire. CAT wanted to retain its right to reuse the frequency until 2025, but the NBTC insisted that the state telecom agency will have only one year to reuse the frequency after its mobile concessions expire with the two operators, who handle 17 million subscribers using the 1800-MHz bandwidth for 2G services.
Mr Wichian said AIS needs to win 1800-MHz spectrum at the auction because the expiry of its concession affects its long-term spectrum management. AIS's concession with TOT Plc on the 900-MHz frequency expires in 2015.
"Our existing bandwidth does not have sufficient capacity to serve growing consumption," he said.
He urged the NBTC to find clearer auction methods for the 1800-MHz band.