
The move follows CAT's approval last week for both cellular operators to develop 3G service.
A source at CAT, which is a state agency, said DTAC planned to roll out 2,100 3G base stations in the greater Bangkok area, Chon Buri and Phuket, while True Move would roll out 650 stations in the same areas except those considered part of metropolitan Bangkok.
The National Telecommunications Commission (NTC) is expected to consider CAT's request within the next two weeks. CAT owns the mobile-phone concessions of DTAC, True Move and Digital Phone (DPC).
DTAC and True Move will develop 3G service on the 800-megahertz spectrum bands.
DTAC has set aside Bt5 billion to develop the service, which will initially debut in Phuket and Chon Buri, followed by Bangkok.
Market leader Advanced Info Service (AIS) stole a march by kicking off 3G service on its 900MHz spectrum in Chiang Mai last month and is waiting for NTC approval to roll out the service in Bangkok. It now has about 1,000 3G users in Chiang Mai.
DPC, a subsidiary of AIS, has repeatedly urged CAT to grant it the 800MHz spectrum for it to develop 3G as well, citing the need to be treated by CAT in the same way it treats True Move.
Earlier True Move had only the 1800MHz spectrum before the CAT board made a decision last week to seek 800MHz spectrum bands for it to develop 3G.
AIS president Wichian Mektrakarn last Friday said CAT should treat DPC fairly, given that DPC had contributed about Bt1 billion a year in network-access revenue to the state agency.
The 3G mobile broadband technology enables compatible phone users to send and receive bandwidth-hungry content like video calls and other heavy files.