Voice over LTE

Voice over Long-Term Evolution (acronym VoLTE) is an LTE high-speed wireless communication standard for voice calls and SMS using mobile phones and data terminals.^[1]^[2] VoLTE has up to three times more voice^[3] and data capacity than older 3G UMTS and up to six times more than 2G GSM. It uses less bandwidth because VoLTE's packet headers are smaller than those of unoptimized VoIP/LTE. VoLTE calls are usually charged at the same rate as other calls.

To be able to make a VoLTE call, the device, its firmware, and the mobile telephone providers on each end, as well as the inter-carrier connectivity must all implement the service in the area, and be able to work together. VoLTE has been marketed as "HD voice" by some carriers, but this is a broader concept. Moreover, HD+ (EVS) is used only in LTE and NR; HD voice was available in 3G too.

^ Poikselkä, Miikka; Holma, Harri; Hongisto, Jukka; Kallio, Juha; Toskala, Antti (2012-03-05). Voice over LTE: VoLTE. John Wiley & Sons. ISBN 978-1-119-95168-1.
^ "Voice and communication services in 4G and 5G networks". Ericsson.
^ "5G Evolution Towards a Super-connected World". Practical Guide to LTE-A, VoLTE and IoT. 2018-06-05. pp. 382–443. doi:10.1002/9781119063407.ch8. ISBN 978-1-119-06330-8 – via VoLTE.

[1] Poikselkä, Miikka; Holma, Harri; Hongisto, Jukka; Kallio, Juha; Toskala, Antti (2012-03-05). Voice over LTE: VoLTE. John Wiley & Sons. ISBN 978-1-119-95168-1.

[2] "Voice and communication services in 4G and 5G networks". Ericsson.

[3] "5G Evolution Towards a Super-connected World". Practical Guide to LTE-A, VoLTE and IoT. 2018-06-05. pp. 382–443. doi:10.1002/9781119063407.ch8. ISBN 978-1-119-06330-8 – via VoLTE.

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