LTE was designed with high capacity and low latency characteristics with packet switch services in mind . There is no circuit switched (voice service ) core network in LTE. Therefore, LTE is very suitable for voice over IP services such as Voice over LTE approach and this technology is used for providing voice service.
For Voice over LTE (VoLTE), Internet Multimedia Subsystem (IMS) is used as a glue to provide voice connectivity with
Also CS Fall back is used with LTE in order to provide voice services in LTE using 2G or 3G Circuit switch network.