Chinese operators have recently started blowing up the 5G network again. A few weeks ago, China Mobile announced its 5G call, a video calling feature that works directly from a smartphone to dial. In addition, China Unicom recently released a 5G video account. All of these technologies focus on the ability to do video calls directly via dial-up connection. Not only is it better than the voice and video features of various social software, but incoming calls can’t interrupt a video call. tthe most convenient thing is that you don’t need to download an app. So the question is, what exactly is 5G VoNR? Why do operators have so much trust and dare to brag like that?

We can call this new technology 5G VoNR technology for high resolution calls. Simply put, when people make calls, it can not only make the call clearer and have lower latency, but also have clearer voice and video quality than in the 4G era. Most importantly, VoNR calls will not affect 5G data transmission, let alone 4G networks.

Restriction for the first days – 3G and 4G

This is quite “common” for phone calls to deterioration of the signal of the mobile telephone network. In the first years when a phone call is on, the phone will do it direct disconnection from the Internet. The webpage cannot be opened at this time. Well, in the 5G era, this problem is not completely over. However, at that time, people didn’t even know what streaming media and mobile social networking were. So, of course, they didn’t think much about it. So operators at the time used a technology that was more intensive and less efficient: switching CS circuits.


Simply put, when we make a phone call, we fully establish a point-to-point line. This line will overtake the bandwidth originally used for data traffic and can only return to normal network status after the call.

It’s like a street with traffic restrictions, except for certain people (you and the caller), no one else can go that way. Even before the restrictions are over, you can only go this route. In those days when you do phone call, if the other party was on the phone, you can only hear the busy beep tone. . .



Later, with the advent of the 3G era, we had the development of social platforms and the speeds of mobile internet became faster. However, voice calling technology has not improved much. At this time, when we use the 3G network to make calls, the signal of a mobile phone will directly decrease to 2G. However, people were still used to calling and texting as their primary means of contact. So this did not cause much disgust in people.


Unexpectedly, with the development of 4G, the speed of the network directly increased significantly and social platforms gradually began to replace text messages and phone calls. However, 4G itself does not support the CS switching scheme, so operators had to allocate Internet services to 4G, while 2G / 3G still works for calls.

At this time it is a little inconvenient to call and disconnect from the Internet. After all, when the call drops directly from 4G to 2G, the difference is really too big. tit is not a good thing for operators because the old technology is difficult to maintain and inefficient.

5G network

As a result, the mobile communications industry has finally come up with a new solution called 4G VoLTE. It can package the data of the phone as a whole and transmit it directly over the network as streaming, without having to create a separate voice channel.

People only need to connect their mobile phones to the 4G network to be able to make calls and surf the Internet at the same time. Thanks to advances in 4G networking technology, the quality of voice calls has also led to unprecedented improvements.

5G network

5G optimization

All the limitations with 2G, 3G and 4G should be the focus and improvement with the 5G network. To quickly launch 5G, operators initially used resources to share 4G and 5G (NSA Independent Network). This was the standard for the 5G network for the first two years (2019 to 2021).

At that time, the coverage level of the 5G dedicated network solution (SA independent network) was not high and not stable enough. If you are in a zone with a weak signal, the phone will repeatedly jump between 4G and 5G networks. If you make a call over the 5G network at this time, you may find that you cannot hear clearly. There is usually a delay or even direct disconnection.

In order to maintain the quality of voice calls and to improve the user experience when making calls, operators must abolish the old method and then repeat the decision to switch to the EPS Fallback voice service.

EPS backup

With this technology, Internet access is transmitted to 5G, and 4G VoLTE is responsible for making calls. It’s just that from that moment on, making phone calls and surfing the internet on a cell phone became one and the same thing. . . While one network speed is reduced, the other must be reduced. Thanks to the fact that 4G VoLTE itself is innovative and easy to use, it saves a small face for making calls on 5G phones.

EPS backup

About EPS Fallback, here’s what Ericsson has to say

“EPS standby mode allows phones to use 5GC with NR before all the necessary voice functions are in place in the phone and in the NG-RAN and before the NG-RAN is sized and tuned for voice. During a call, the phone moves from NR (5G) to LTE (4G) and the call is finally set to 5G. So, for the initial call: you’re dialing 5G, but you’re talking 4G.


Now the 5G VoNR is actually equivalent to “let 5G go back to 5G”. No need to occupy the east wing of his 4G brother. In essence, the difference between 5G VoNR and 4G VoLTE is not very big. This is not so much an iteration of voice technology as creating better conditions for using the 5G network.

Unfortunately, some of the earliest 5G smartphones do not support it 5G VoNR. AAlthough the advent of 5G VoNR can bring a better experience if mobile phones do not meet the requirements, there is no need to change them. Just like this new 5G mobile call, it has a direct video calling feature. If we say that it is useful in terms of major achievements, it does not differ from what social platforms offer.

For now, the benefits of the 5G network that ordinary users can feel are nothing more than a larger network bandwidth. There are also the advantages of advanced voice coding technology and better data transmission effects.

Here is how Chinese operators are optimizing the 5G network

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