LTE vs VoLTE | difference between LTE and VoLTE, Voice Over LTE

This page compares LTE vs VoLTE (Voice Over LTE) and describes difference between LTE and VoLTE (Voice Over LTE).

LTE has been developed to support data based applications. It is also possible to use it for voice calls. LTE is all IP network and hence there are two options to support voice calls through LTE network. The first option is using voice over IP (VoIP) with IMS support. The second option is legacy fall back to other cellular networks such as 2G/GSM or 3G/CDMA.

VoLTE using VOIP through IMS

All the mobile phones do not support VoLTE and hence LTE to VoLTE converter applications are required to be installed in order to use the VoLTE feature.

• VoLTE supports fast call setup compare to 2G/3G networks.
• The battery life has been enhanced.
• HD voice calls can be made using VoLTE.

The figure-1 depicts VoLTE using VoIP protocols. Refer VoLTE basics >> and VoLTE originating call flow >>.

Following table summarizes difference between LTE and VoLTE.

Specifications LTE VoLTE
Full Form Long Term Evolution Voice over LTE
Main application It is developed to support data only applications.
LTE = Only Data Transmission
It is developed to support both voice and data transmission.
VoLTE = Call + Data Transmission
Quality of Voice transmission Quality of voice reduces when data connection is ON. Voice quality remains excellent in the presence of data connection.
Switching Type LTE uses packet switching only. VoLTE utilizes existing packet switched LTE network to provide HD voice calls.
Call setup It is slower compare to VoLTE. It is much faster compare to LTE.
External application software It requires external app. such as skype/Whatsapp for video calling. With VoLTE one can directly call anyone irrespective of external app.
Free calling Continuous internet data is needed to make free calls. User can not switched it OFF. User can make free calls even if internet connection is switched OFF.
Battery Data and battery are highly drained. Data and battery are not much drained unlike LTE.


This tutorial section on LTE basics covers following sub topics:
LTE tutorial  LTE features  LTE terminologies  Frame  TDD FDD  Channel types  PHY  stack  throughput  CA   cell search  network entry  Timers  PSS vs SSS  Security   LTE Bands  EARFCN  Hotspot  router  What is VoLTE  VoLTE originating call flow  VoLTE UE attach and registration procedure 

Difference between LTE Advanced vs LTE Advanced Pro vs 5G Links

Article on LTE Advanced>>   LTE-a vs LTE-a Pro>>   5G vs LTE Advanced Pro>>  

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