What is 5G VoNR?

The move to a cloud-native core enables 5G VoNR services

While most current 5G network deployments are in the Non-Standalone mode of operation wherein 5G radios supporting new frequencies are attached to an LTE Evolved Packet Core. But operators are quickly gearing up to transition to 5G Standalone, meaning a new cloud-native core is deployed. This transition enables a whole host of new service and delivery models including 5G Voice over New Radio or 5G VoNR.

Unlike its predecessor Voice over Long Term Evolution (VoLTE), 5G VoNR removes the LTE anchor allowing the voice call to stay on a 5G network from the UE, through the RAN and core. 5G voice calls are implemented as end-to-end Voice over IP (VoIP) connections managed by the IP Multimedia System (IMS) core; IMS is an architectural framework for delivering multimedia communications services.

In a white paper on the topic, Rohde & Schwarz wrote: “This IMS architecture will play an increasingly important role in 5G VoNR. While IMS can provide voice services for any type of access (fixed, cable and 2G/3G) as well as for any 5G-deployment model, 5G is not as flexible and absolutely has to have an IMS network to handle voice services no matter the type of deployment.”

The benefits of 5G VoNR

So why is this important for operators and their customers? “High quality and seamless voice calling remains a must-have service for our customers in the 5G,” Deutsche Telekom’s Alex Choi, SVP of Strategy and Technology Innovation, said in June when the operator completed a 5G VoNR call. “The addition of 5G VoNR can be a differentiator for next generation immersive applications that integrate high speed 5G data with high-definition audio.”

That testing involved an Ericsson 5G Core, IMS from Nokia and Samsung and Xiaomi handsets, as well as a test device from Qualcomm.

Nokia explored Choi’s reference to applications beyond just voice calling in a paper titled “Voice over 5G: A vision for the future of voice services.” One the primary opportunities identified is carriers taking back enterprise voice from over-the-top (OTT) players by leveraging their investments in IMS, ongoing advancements into voice-based user interfaces, and a growing developer community.

Per Nokia, “This is where IMS holds potential to help [operators] develop value-added services that integrate voice within other applications and especially enterprise services. IMS, which is the core voice technology ensuring QoS in both VoLTE and [VoNR], is both standardized and optimized. It is a much more powerful technology than the OTT VoIP used by many enterprise voice services. The quality of calls and video is superior and fully integrated in the handset, which makes it more user-friendly. High-definition voice and video calls can be integrated with other services as well.”

M1 commercializes VoNR, Vodafone Idea trialing

Singaporean operator M1 Limited and Samsung said in July they made available Voice over 5G VoNR services on its Standalone 5G network. M1 called out the ability, with the upgrade to VoNR, for faster call setup time and call continuity.

“We have once again reached a groundbreaking milestone in our 5G SA journey – to be the first in the world to successfully support VoNR service on our 5G SA network,” M1 CTO Dennis Seek said in a statement. “We are glad to work with Samsung to achieve high quality call and better 5G experience for our customers. With M1’s imminent market trial of the 5G SA network, we are excited to leverage 5G SA’s low latency, ultra-responsive, highly secured and high-throughput mobile connectivity to deliver high performance and reliable 5G services for our consumers and enterprises.”

In India, although 5G has yet to be rolled out given delays in spectrum auctions and allocations, Vodafone Idea demoed 5G VoNR using frequencies set aside by the national regulator for operator trials.

Vodafone Idea used Nokia’s 5G RAN, core and IMS technologies to test out high-definition voice. CTO Jagbir Singh said the ultimate goal is to enable “use cases of relevance to digital enterprises and consumers…We have now successfully tested VoNR service which offers the best call quality on 5G networks.”