VoLTE: The Most Emerging Technology in LTE Domain

Globally most of the mobile service providers already on LTE or deploying LTE on their network. As far as we are concerned about Indian landscape, here the big players all are offering LTE. 

As the global trends show the universal acceptance of VoLTE (Voice over LTE) – for offering voice calls over IMS (IP Multimedia Subsystem) architecture based LTE networks, here in India apart from BSNL, all serious players (Airtel, Reliance Jio, Vodafone/Idea) are launching VoLTE or already launched it. Reliance Jio is completely on VoLTE, while Vodafone is offering it in ten circles, followed by Bharti Airtel in nine circles. Idea Cellular has opened the VoLTE to its employees, which is expected to go official for the users in some circles very soon, but there’s no word on the same.

Reliance Jio is completely on VoLTE, as the telco doesn’t have any legacy voice network on 2G/3G. Others telcos have the Circuit Switched Fall Back mechanism based voice on 2G/3G and data on LTE initially, later they are moving on to VoLTE.

Why is VoLTE gaining momentum in the country? The reason is simple – better spectrum efficacy, refarming of spectrums that is being used on 2G/3G networks, better services like HD voice and video calling are the main reasons. 


VoLTE was launched in 2012, initially developed by South Korean mobile service providers KT and NTT Docomo. The first commercial launch of VoLTE came in 2014 from SingTel telecom operator in Singapore. While India saw VoLTE trials from 2015 by Reliance Jio, it was in September 2016 the service was launched commercially. India has very low technical gap in case of VoLTE, thanks to Jio.

At the beginning of Q2 2018, there are more than 140 carriers across the globe having commercial VoLTE services, 165+ operators have invested on VoLTE and 102 operators have launched HD Voice on VoLTE, as per data from Juniper Research and GSA.

As the technology gets wider acceptance, there is global roaming and interoperability agreements are also being set.

Interestingly, before the launch of 4G/LTE, there was talk that operators’ voice revenue is being eaten by OTT players like Skype, Whatsapp, Facebook messenger calling etc. But the latest data from SNS Telecom & IT reveals that globally VoLTE will make over $280 billion annually by 2021, driven by 3 billion VoLTE subscribers that time (compared to 488 million VoLTE subscribers in 2016). And VoLTE will likely overtake the OTT app based voice services – VoLTE usage will be over 10 trillion minutes by 2021, which is equivalent to 3.3 trillion music tracks.

Sam Barker, the analyst at Juniper Research, explains, “Operators have historically used service coverage as a differentiation point; selling the notion of always available. The depth and breadth of high-quality voice services will now serve to enrich that offering and entice users: always available, always best-in-class.”

What to expect in the Indian market:

VoLTE will grow, and as it grows, the most crucial effect will be seen by closing down legacy 2G/3G networks. Indian operators will shut down 3G networks first, followed by the closure of 2G services phase by phase. They will refarm the spectrum for LTE rollout and roll out LTE-CA (Carrier Aggregation) by laying several LTE networks side by side. As Indian government will always go for auction of spectrum, operators may skip major investment on spectrum buy out, rather may start next-Gen techs like mmWave 5G on the existing spectrum.

As of now, Jio has 100% VoLTE coverage on its LTE network; Airtel comes second while Idea and Vodafone have started rolling out VoLTE in certain big cities.

Already we have several VoLTE supported feature phone (Reliance JioPhone, Micromax Bharat 1, Intex Turbo+ 4G and others), so even voice only customers will shift to it in coming days.

This story was originally published on Telecomtalk.info