Chinese operators have recently started to blow 5G network again. A few weeks ago, China Mobile announced its 5G Call, a video call feature that works directly from the smartphone dialer. Also, recently, China Unicom also launched the 5G video account. All these technologies center around the ability to make video calls directly through dial-up. Not only is it better than the voice and video functions on various social software, but incoming calls also can not interrupt the video call. The most convenient thing is that there is no need to download an app. So the question is, what exactly is this “5G VoNR”? Why do operators have so much confidence and dare to brag like this?
We can call this new technology 5G VoNR high-definition call technology. Simply put, when people make calls, it can not only make the call clearer and have lower latency but also have a clearer voice and video quality than in the 4G era. The most important thing is that making calls under VoNR technology will not affect 5G data transmission, let alone 4G networks.
Early days restriction – 3G and 4G
It is quite “usual” for phone calls to degrade the signal of the mobile phone network. In the early years, when a phone call is on, the phone will directly disconnect from the Internet. At this point, a web page can not open at all. Well, in the 5G era, this problem is not completely over. However, at the time, people didn’t even know what streaming media and mobile social networking were. Thus, they naturally did not think much about it. So operators at the time used a technology that was more resource-intensive and less efficient: CS circuit switching.
Simply put, when we make a phone call, we establish a completely “point-to-point” call line. This line will preempt the bandwidth originally used for data traffic and can return to the normal network state only after the call ends.
It’s like a street with traffic restrictions, except for certain people (you and the caller) no one else can pass on this road. Even before the restrictions are over, you can only go this way. In those days, when you make a phone call, if the other party was on the phone, you could only hear the busy tone of “beep beep”. . .
Later, with the advent of the 3G era, we had the development of social platforms and mobile internet speeds became faster. However, the technology for voice calls did not improve much. At the time, when we use the 3G network to make calls, the mobile phone signal will directly reduce to 2G. However, people were still used to calling and sending text messages as the main means of contact. Thus, this did not cause people’s special disgust.
Unexpectedly, with the development of 4G, the network speed directly increased significantly and social platforms gradually started to replace text messages and phone calls. However, 4G itself does not support the CS circuit switching scheme, so operators had to allocate internet services to 4G while 2G / 3G still works for calls.
At this time, it is a bit uncomfortable to make calls and disconnect from the Internet. After all, when a call directly drops from 4G to 2G, the gap is really too big. This is not a good thing for operators, because the old technology is troublesome to maintain and inefficient.
As a result, the mobile communication industry finally came up with a new solution called “4G VoLTE”. It can package the data of the phone as a whole, and transmit it directly through the network like streaming, without having to establish 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. Due to the advancement of 4G network technology, the quality of voice calls has also ushered in an unprecedented improvement.
All the restrictions with 2G, 3G and 4G need to be the point of focus and improvement with 5G network. In order to hurriedly put 5G into use, operators initially used 4G and 5G sharing resources (NSA non-independent networking). This was the standard for 5G network for the first two years (2019 to 2021).
At that time, the coverage rate of the 5G dedicated network solution (SA independent networking) was not high and not stable enough. If you are in an area with poor signal, the phone will repeatedly hop between the 4G and 5G networks. If you make a call through the 5G network at this time, you may find that you can’t hear clearly. There is usually a delay or even a direct disconnection.
In order to maintain the quality of voice calls and improve the user experience of making calls, operators have to take out the old method and then iterate the “EPS Fallback” voice service transition solution.
In this technology, Internet access is handed over to 5G, and 4G VoLTE is responsible for making calls. It’s just that from this time on, making a phone call and surfing the Internet on a mobile phone have become the same thing. . . As long as one network speed is downgraded, the other one has to be downgraded. Thanks to 4G VoLTE itself being innovative and easy to use, it saves some face for making calls on 5G phones.
Regarding EPS Fallback, here is what Ericsson has to say
“EPS fallback enables phones to use the 5GC with NR prior to all needed voice features are in place in the phone and in NG-RAN and before the NG-RAN is dimensioned and tuned for voice. During call establishment, the phone is moved from NR (5G) to LTE (4G) and the call is finally established on 5G. So, for an originating call: you dial on 5G but you talk on 4G ”.
Now the VoNR of 5G is actually equivalent to “let 5G return to 5G”. There is no need to borrow the east wing of its 4G brother. Essentially, the difference between 5G VoNR and 4G VoLTE is not very big. It’s not so much an iteration of voice technology as it is to create better conditions for the use of 5G network.
Unfortunately, some of the earliest 5G smartphones do not support 5G VoNR. Although the emergence of 5G VoNR can bring a better experience if the mobile phones do not meet the requirements, there is no need to replace them. Just like this new mobile 5G call, it features a direct video call function. If we say it is useful, in terms of basic achievements, it is not different from what social platforms offers.
For now, the benefits of 5G network that ordinary consumers can feel are nothing more than larger network bandwidth. There are also the benefits of advance voice coding technology and better data transmission effects.