VoLTE – What difference does it make?
There has been over 140 years of voice service in telecommunications and it’s still going strong. The latest major improvement has been introduction of VoLTE. Utilizing IMS technology, it is a digital packet voice service that is delivered over IP via an LTE access network.
From the end-user perspective, customers can enjoy superior voice quality compared to legacy 2G/3G voice calls making it easier to perceive what the speaker on the other end says and to hear more subtle tones. To be able to enjoy the offered high voice audio quality both call parties must have VoLTE (Voice over Long Term Evolution) compatible terminals. Typically calls are connected twice as fast as legacy 3G calls and the difference is even bigger with 2G calls. VoLTE is QoS guaranteed service what e.g. WhatsApp cannot provide. VoLTE can also save battery life as mobile doesn’t need to switch between LTE and UMTS/GSM systems and measure for a different signal every time during a call setup procedure.
From the operator point of view previously mentioned customer satisfaction is obvious. In addition to that, they are looking for savings. As voice is implemented with LTE, depending on VoLTE capable terminal penetration, legacy CS voice infrastructure can potentially be shut down in the near future, even partially, and simplify the network architecture; data and voice will both use IP technology. Consequently, it would enable reusing of legacy radio bands like 900 MHz, 1800 MHz and 2100 MHz with newer generation mobile services or e.g. LTE carrier aggregation to enhance the network capacity. VoLTE also provides more effective use of radio spectrum than traditional CS service.
VoLTE is built on top of IMS (IP Multimedia Subsystem – by the way, the same will be used also with 5G voice) which unlocks new revenue potential. The same platform can be used commonly for other services such as video calls and other rich content guaranteed reliable services. Building of globally connected VoLTE services (roaming) has started but is still in the early phase.
Status of VoLTE
According to the Ericsson Mobility Report Nov 2018 there would be almost 1.4 billion VoLTE subscriptions by the end of 2018, and it will grow to 6 billion by the end of 2024. VoLTE has been launched in more than 155 networks in over 75 countries. This is also supported by the fact that nowadays operator benchmarks also include VoLTE measurements as de facto.
Regardless of the growing number of VoLTE subscriptions, Omnitele has learned that VoLTE implementation and launching has needed more work and testing than previous technologies. For example, tackling the challenge of strict phone manufacturer requirements for VoLTE capable network and customisation of the IMS platform have been new procedures, involving time-consuming network and terminal testing and approval.
Omnitele assists operators in implementing VoLTE services and optimising the LTE RAN infrastructure and continuous LTE coverage as well as in assuring the correct functioning of the Single Radio Voice Call Continuity (SRVCC) feature, in case VoLTE calls have to be handed back to 3G/2G network layers.
Furthermore, Omnitele offers end-to-end verification of VoLTE services as well as measurement and benchmark campaigns including VoLTE.