2. After entering the dual card and mobile network, click SIM card 1.
3. Click the VoLTE close button again to close it.
VoLTE (Voice over LTE) is a voice service based on IMS. It is an IP data transmission technology, which does not need 2G/3G network, and all services are carried on 4G network, which can realize the unification of data and voice services under the same network. In other words, 4G networks not only provide high-speed data services, but also provide high-quality audio and video calls, all of which require VoLTE technology.
Because it supports multiple access and rich multimedia services, it has become the core network standard architecture in the all-IP era. After several years of development and maturity, IMS has now crossed the rift valley and become the mainstream choice for the transformation of VoBB and PSTN networks in the fixed voice field, and has also been determined as the standard architecture of mobile voice by 3GPP and GSMA.
References:
Volte- Baidu Encyclopedia