VoLTE stands for Voice over Long-Term Evolution or Voice over LTE. It is a high-speed wireless communication standard for voice calls using mobile phones and data terminals. VoLTE allows voice calls to be transmitted over the LTE/4G mobile network, which has up to three times more voice and data capacity than older 3G UMTS and up to six times more than 2G GSM. Previously, 4G was limited to surfing the Internet, and when it came to calls, the phone would automatically switch to 3G or 2G. With VoLTE, this is no longer necessary, and there is no delay before the recipients phone rings.
VoLTE is based on the IP Multimedia Subsystem (IMS) architectural framework, with specific profiles for control and media planes of voice service. This facilitates VoLTE on the LTE wireless broadband service defined by GSMA in PRD IR.92. The voice service (control and media planes) is delivered as data flows within the LTE data bearer, with no dependency on (or ultimately, requirement for) the circuit-switched voice network to be in the call path.
The benefits of VoLTE include higher-quality audio traveling both ways, faster call connection times, and the ability to use more bandwidth to make phone calls. When calling over LTE, you can use 4G/LTE data services, such as web surfing and tethering, while simultaneously making and receiving calls. Additionally, on a 4G LTE network, both calls and data work in unison, meaning that a text message will arrive instantly even during a call.
