This week KDDI [9433.DE] has passed the 10 million subscriber mark for its CDMA2000 1x-based 3G service, just 18 months after launch, while DoCoMo [DCM] is enjoying renewed FOMA subscriber growth.

DoCoMo’s FOMA, closely watched by analysts in Europe because the underlying W-CDMA technology is a variant of the UMTS standard chosen by Western operators, now covers some 96 percent of the Japanese population. Handset sizes have been reduced, feature sets have been improved and the battery life increased.

The result has been steady, albeit relatively slow, growth in FOMA subscriber numbers, which rose to 786,000 in August 2003. DoCoMo has added new subscribers at the rate of about 123,000 per month since June 2003.

Most importantly, the operator appears to have overcome the technical difficulties that plagued the services in its early stages. It has today announced that it will deploy a large number of micro-base stations to boost coverage in indoor and sparsely populated outdoor areas. The new stations are less than one-thirtieth the size of the existing main base stations and cost significantly less to install.

DoCoMo is also expanding its international co-operation, launching a service earlier this week that enables FOMA subscribers to conduct video calls with subscribers to Hutchison’s 3G network in the UK.

However, Hutchison [0013q.L] is yet to demonstrate it can overcome the technical problems and lacklustre response that have greeted its launch in the UK market.

Users continue to complain of problems with handsets, the absence of widespread 3G coverage and frequently running out of battery power to make calls.

Subscriber numbers are rising on the back of heavy marketing, tariff discounts and special handset subsidies, but it seems unlikely the company will meet its year-end target of one million UK subscribers.