The VoLTE services on China Mobile’s 4G TD-LTE network, constructed by ZTE, support enhanced single radio voice call continuity (eSRVCC) switching for seamless handovers to non-4G networks. The eSRVCC technology complies with the LTE-A 3GPP R10 standard, and greatly reduces latency times when switching voice services between a 4G network and 3G or 2G networks, ensuring that users do not perceive any change when moving between different networks. The VoLTE deployment in Guangzhou was also enabled by a newly-built IP multimedia subsystem (IMS) system provided by ZTE. 4G smartphones with Qualcomm® Snapdragon™ 800 processors were recently used to demonstrate the system.
"The successful demonstration of the VoLTE service speeds up the development of the entire industry ecosystem,” said Mr. Sha Yuejia, vice president of China Mobile.
Mr. Sha and Ms. Wang Xiaoyun, general manager of the Technical Department of China Mobile conducted video calls using the VoLTE service from a vehicle in the urban area of Guangzhou. They also witnessed the capabilities of ZTE’s eSRVCC solution when voice calls were seamlessly handed off from 4G networks to third-party 2G networks, a key to the future commercialisation of the service.
The successful VoLTE deployment by China Mobile was completed using network systems and terminals from different vendors, showing the feasibility of eSRVCC for all China Mobile’s networks.
ZTE has led the industry globally in deploying VoLTE services on 4G TD-LTE networks. In July 2013, ZTE cooperated with Qualcomm to conduct a VoLTE test using commercial terminals in China Mobile's lab. In December 2013, ZTE completed calls over TD-LTE VoLTE between Guangzhou and Tianjin.
The latest collaboration between ZTE and China Mobile, together with their partners, has brought TD-LTE VoLTE service closer to commercial reality, delivering superior user experience to subscribers.