NTT DoCoMo has decided to work with Cingular Wireless on 3G cellular telephone technology following Cingular's acquisition of NTT DoCoMo's current US partner, AT&T Wireless Services, according to reports.
NTT DoCoMo, which is Japan's leading cellular carrier, currently holds a 16% stake in AT&T Wireless as the result of a 2001 deal under which the two were to work on the rollout of 3G services in the US. The services were to be based on DoCoMo's preferred WCDMA (Wideband Code Division Multiple Access) technology.
NTT DoCoMo has been quiet on its plans for the US market ever since Cingular said in February this year that it will pay $41bn (£23) to acquire AT&T Wireless. The acquisition deal, which Cingular said could be finalised by the end of this year, is expected to make Cingular the leading US cellular carrier in number of subscribers.
Partnership negotiations between DoCoMo and Cingular have already begun, although the fine details of a tie-up are not expected to be agreed upon until after Cingular's acquisition of AT&T is complete, according to the a Japanese newspaper.
The partnership with Cingular is likely to mean DoCoMo sharing WCDMA technology, telephone handset software and specifications for its I-mode wireless internet service, and the two allowing reciprocal roaming on their networks, the report said.
NTT DoCoMo and Cingular could not immediately be reached for comment.
The deal between DoCoMo and AT&T Wireless was reached at the height of the internet and 3G telecommunication bubble and saw the Japanese company pay about $8bn to get its foot into the door of the US market. However, DoCoMo wrote off most of the investment in 2003 after AT&T Wireless share prices fell and remained at levels well below those of 2001.
While the deal represented a considerable financial loss for DoCoMo, there has been some technical success: AT&T Wireless launched a WCDMA-based 3G service in Detroit, Phoenix, San Francisco and Seattle in July this year.
Meanwhile, Verizon Wireless, currently the largest US cellular carrier, said it plans to expand its 3G service to 14 US markets and 20 airports before the end of this month. Verizon's service is based on the competing and incompatible CDMA 2000 1x EV-DO technology.
Martyn Williams writes for IDG News Service