KDDI are Japan's second largest mobile phone network with around 41 million [at end 2014] (almost exclusively postpaid) subscribers, mostly using CDMA technology rather than the more common GSM/UMTS. Their 3G femtocell was launched in July 2010.
A femtocell trial was awarded to Hitachi and Airvana early in 2010, following a much earlier partnership announced between the two vendors in 2008. Airvana will provide their HubBub femtocell, Femtocell Service Manager and femtocell network gateway, with Hitachi providing other core network components and system integration to provide a complete solution. Testing started in March 2010.
After successful trials, KDDI announced commercial availability of their 3G CDMA femtocell from 1st July 2010, again using equipment from Airvana/Hitachi. This is the first 3G CDMA commercial launch. The service is targetted at customers who have poor 3G reception at home and is apparently free. An engineer visits to inspect and assess the issue, installing either a repeater or 3G femtocell to address the problem. At this time, regulators require that all basestations (including femtocells) must be installed by a qualified engineer in Japan, although all operators are encouraging the officials to relax these restrictions.
The service is called au Femtocell
During their LTE rollout in 2013, they deployed picocells to ensure seamless coverage as part of a HetNet strategy, explained by their CTO office representative in this interview.
KDDI has also partnered with Ruckus Wireless to deploy 100,000 Wi-Fi hotspots to offload traffic.