Qualcomm has completed the first voice call handover from an LTE mobile network to a WCDMA network using Single Radio Voice Call Continuity (SRVCC).
Being an important technology required for voice-over-LTE (VoLTE) support, SRVCC is a 3GPP specified feature that enables continuity of service by switching to a WCDMA network when a consumer on a VoLTE call leaves the LTE network’s coverage area.
The VoIP-over-LTE call is enabled through Ericsson’s network using a handset which incorporated Qualcomm’s Snapdragon S4 MSM8960 3G/LTE multimode processor.
SRVCC is the next logical step in the 4G LTE voice roadmap following the launch of circuit-switched fallback technology (CSFB) on smartphones in 2011.
CSFB allows a single radio in the handset to switch from an LTE data connection to a 3G connection when the user needs to make or receive a call, while with the support of SRVCC, a single radio in the handset can execute a handover of a voice call from an LTE network to a 3G network.
SRVCC and CSFB also allow both LTE and 3G network connections to be supported on a single chip, eliminating the need for smartphones to use separate LTE and 3G radios and modems.
Qualcomm Product Management senior vice-president Cristiano Amon said as LTE networks are deployed alongside 3G networks, the ability for multimode 3G/LTE mobile devices to connect to different network technologies will be an important part of providing the best possible mobile voice and data experience to consumers.
"Qualcomm is committed to the successful deployment of LTE networks worldwide in conjunction with 3G networks, and the milestone we’ve achieved with Ericsson is another step towards making VoLTE technology a commercial reality," said Cristiano.
