With the advent of iOS 8.3, "VoLTE" can be used on iPhone 6 / iPhone 6 Plus of DoCoMo / au / Softbank. However, many people are not sure what VoLTE is and what its benefits are. In this article, I will explain in Q & A format, including how to use it.
Q1 What is VoLTE in the first place?
A1 LTE data communication technology for making voice calls
VoLTE stands for "Voice over LTE" (commonly read as "Volte" in the mobile industry). It is a technology that realizes voice calls on the LTE network originally developed for data communication.
Until now, even if smartphones support LTE, communication was automatically switched from LTE to 3G when using voice calls.
Q2 In other words, is VoLTE similar to Skype or LINE?
A2 Basically different from Skype and LINE where call quality is not guaranteed
In terms of realizing voice calls by data communication, it is the same as Skype and LINE, but VoLTE secures bandwidth for calls, has a small delay, and ensures reliable calls. In addition, functions provided by conventional voice calls such as answering machines are also available. In that respect, it is clearly different from Skype and LINE.
On the contrary, even if you make a call with VoLTE, there is not much opportunity to feel the difference (except for the sound quality described later) from when you make a call with a smartphone so far.
Q3 So what are the benefits of VoLTE?
A3 Improved sound quality, high-speed communication is possible with LTE even during a call
In LTE, frequencies can be used more efficiently than in 3G, and sound quality has been greatly improved with the new generation of audio compression technology. In 3G, the voice feels like a sword, but in VoLTE, you can talk with a natural voice.
From the materials on the au site.The band of the corresponding voice frequency has been expanded, and especially the high-pitched sound can be heard without a basket.
Also, when the other party is in a noisy place, the surrounding sounds become distorted and can be heard with the microphone, so it is necessary to concentrate on listening to the story, but with VoLTE, the environmental sound is also clear and the conversation becomes much easier. Become.
In addition, VoLTE enables high-speed LTE communication even during a call. Data communication itself during a call was possible with DoCoMo and Softbank's iPhone (au is not possible in the first place), but the connection is switched to 3G and the communication speed is up to 384 kbps. With VoLTE, operations such as viewing a map while talking on the phone are easy.
Conventionally (left) switches to 3G during a call, but VoLTE (right) remains LTE.
Another merit that I would like to pay attention to is the short ringing time. Especially if you are using VoLTE terminals, you will be surprised when you use it for the first time because it will connect to "Puppup" in about 2 seconds.
Q4 Which iPhone can use VoLTE?
Compatible with A4 iPhone 6 / iPhone 6 Plus Currently, only the same carriers
To use VoLTE, the terminal itself must support VoLTE. If it is an iPhone, it will be iPhone 6 / iPhone 6 Plus. For Android smartphones, DoCoMo has been compatible with the model since last summer, au has been compatible with the model since last winter, and Softbank is compatible with "AQUOS CRYSTAL X".
Also, at the moment, it does not support VoLTE connection between different carriers (if it is a DoCoMo VoLTE terminal, only if the other party is a DoCoMo VoLTE terminal). From a global perspective, VoLTE connections between different carriers are still in the future, and it seems that support will not be immediate. Even if one is connected by VoLTE, if the other is a smartphone that does not support VoLTE or another carrier, the sound quality will basically be the current level.
VoLTE calls are possible between Android and iPhone if they are the same carrier
VoLTE on iPhone and Android is possible between the same carriers. However, there are some services that are not available on the iPhone, such as docomo "Video Call", au "Sync Call" and "Voice Party", which are provided for VoLTE compatible Android smartphones.
Sync call, which is the main feature of au VoLTE, cannot be used on iPhone.
Q5 What is the price of VoLTE?
A5 No change from the past
Call charges are the same for all three carriers. There is no additional charge, but on the contrary, there is no discount exclusively for VoLTE. The same applies to domestic flat-rate calls.
Q6 What happens if I go out of the LTE area?
A6 Switch to 3G and continue calling au is LTE (4G) only
Similar to data communication, DoCoMo and Softbank have a technology that automatically switches the network to 3G, so even if there is a momentary interruption, the call should basically continue.
When the VoLTE function is turned on, au basically uses only LTE (4G), including data communication. au "4G LTE" covers almost the whole country with a population coverage rate of over 99%. Also, even in places where the connection is switched to 3G, such as inside a building, in reality, it is often connected by LTE. You don't have to worry too much about not being able to use 3G.
au "4G LTE" has almost the same area as 3G. In the VoLTE era, the quality of the service area will be important, such as whether there are holes in the LTE area.
(On the next page, "How do I use VoLTE on my iPhone?")
