- T-Mobile is continuing it relationship with Ericsson for network expansion, utilizing Ericsson's LTE equipment and services, and Ericsson LTE-Advanced enhancements for T-Mobile's Wideband LTE network. The scope of the expansion builds on the earlier contract which was signed in 2012 for network transformation to now cover the expansion of its nationwide 4G LTE and LTE-Advanced network coverage, deployment of VoLTE service with seamless handover to circuit switched voice and WiFi, and WiFi calling service.
- Ericsson has enabled Wi-Fi calling through its evolved Packet Data Gateway (ePDG) and interoperates with T-Mobile's existing IP Multimedia System and Evolved Packet Core network infrastructure.
According to Ericsson, T-Mobile is the first U.S. wireless carrier to deploy enhanced Single Radio Voice Call Continuity (eSRVCC) technology, which enables a seamless handover of VoLTE calls in LTE to existing 2G or 3G networks, ensuring a customer's experience is seamless. Ericsson has also delivered its Session Border Gateway (SBG) and Ericsson Media Resource System (MRS) to support voice handovers using eSRVCC.