Japan's NTT DoCoMo has become the first member of the Global Certification Forum to open up a VoLTE network for field trials.
The move aligns with the forum's goal of encouraging mobile device manufacturers to verify the interoperability of their devices with VoLTE commercial networks.
As well as the VoLTE network, DoCoMo is providing a carrier aggregation network to support the immediate development of devices.
DoCoMo launched VoLTE services in June 2014. The operator joined the GCF upon its founding in 1999 and was selected as one of the forum's 21 field trial qualified operators in 2005.
The GCF is an independent certification scheme to promote interoperability between mobile devices and networks. It is based in London.
The forum is considered the de facto standard for device certification for 3GPP/2 technologies – GSM, 3G/UMTS, LTE and CDMA2000.
In a statement announcing the move, DoCoMo said it plans to continue to facilitate wider adoption of VoLTE and carrier aggregation with more initiatives.