These days, a new term called “VoLTE” is making its rounds in the technology sphere. Mobile carriers around the globe are slowly replacing the traditional voice networks with this technology. VoLTE is often speculated to be the next generation of mobile telecommunications, that will change the way we communicate over the phone. So what is VoLTE? And why is it gradually replacing the legacy voice call technology that mobile operators have been using for so long?

Today, most mobile network providers transmit voice calls over the traditional circuit-switched (GSM/CDMA) network, while Internet access and other data services are provided over the IP-based packet-switched 3G, 4G LTE network. Both of these channels cannot operate at the same time, and that’s why it’s usually not possible to browse the Internet and talk on the phone at the same time.

VoLTE allows mobile operators to transmit both voice and data over packet-switched LTE network. In other words, voice calls are transmitted as data packets in the same way as emails, WhatsApp messages, and all other Internet-based communications are.

 
Hardware and Software requirements for VoLTE

In order to make or receive VoLTE calls, mobile devices must include 4G LTE radios and be equipped with software that will allow the VoLTE function. Additionally, your wireless carrier must also support VoLTE calls. Some wireless networks might use specific LTE channels for VoLTE alone, so your smartphone must include the antennas required to support those signals.

 
VoLTE vs. VoIP

It might seem like VoLTE and VoIP are the same things, but they are not.

VoIP (Voice over IP) is a technology that allows voice calls to be routed through any internet connection, be it cellular data or the broadband internet at your home or office. Apps like Skype or Viber are built on VoIP technology. On the other hand, VoLTE only works over an LTE connection and is directly integrated into the mobile device’s dialer app.

VoIP uses the Internet to make and receive calls, so you’ll be charged on the amount of data consumed depending on your Internet plan. Some VoIP services might additionally charge money for using certain special features; such as, VoIP to traditional phone calls. Conversely, VoLTE services are generally free of any data charges, but your network operator might impose special tariffs for those services, similar to what you have for regular voice calls.

It’s not possible to make a VoIP call without an Internet connection. But if you’re on a VoLTE supported network, you might be able to make a VoLTE call even if without a data pack.

 
Benefits of VoLTE

In the long run, VoLTE will benefit wireless carriers more than the consumers. Eventually, they would have to manage only one network for both voice and data, which is more efficient in delivering voice services than the older circuit-switched voice network. Routing voice over LTE also enables wireless carriers to free up the spectrum that was earlier reserved only for traditional voice services. Thus VoLTE offers a better, cost-effective solution for mobile operators.

That being said, consumers will also see some benefits as carriers switch to VoLTE. Some of these are as follows:

Faster call setup times: Connecting calls over VoLTE is much faster than connecting traditional voice calls. According to T-Mobile CTO Neville Ray, VoLTE call setup should be twice as fast as that of traditional voice calls.

High quality voice: Legacy voice systems only transmit sounds within 300-3400 Hertz frequency range. With VoLTE, voice calls are transmitted over a much wider frequency range (50-7000 Hertz for the AMR-WB standard, and 20-20000 Hertz for the AAC-ELD standard). This results in crispier, higher quality in-call audio.

Rich Communication Services (RCS): VoLTE will enable wireless operators to offer a host of new services, including video calling, file transferring, real time language translation, video voicemail and instant messaging. Many of these applications are already being delivered over IP-based Internet services using third-party apps, such as FaceTime, Skype, etc.

Lower power consumption compared to VoIP: Even though LTE consumes much of the smartphone battery in general, VoLTE calls still consume much less power compared to that consumed by VoIP services such as Skype (according to a report released by Signals Research Group).

Use voice and hi-speed data simultaneously: Since VoLTE transmits both voice and data as packet-switched streams, there is no need for Circuit-switched fallback. And hence, you can experience high quality voice calls and high-speed internet on your LTE network at the same time.

No Data charges: Even though VoLTE utilizes the network’s data channel, most of the VoLTE services are charged on your regular voice plan rather than the data plan. So even if you have a zero data balance, you would be able to make a VoLTE call.

 
Is VoLTE the future of telecommunications?

VoLTE effectively renders the older GSM or CDMA based voice technologies obsolete, and maybe the day is not far when VoLTE will completely replace the traditional GSM and CDMA based voice call services. But it depends on several factors like network coverage by wireless carriers, availability of supported devices, user adaptability, etc.

For now, VoLTE suffers from the following setbacks:

Dropped calls: VoLTE requires both the caller and the callee to be within the LTE network coverage. If either of the persons are not in LTE coverage, the call would be switched to the GSM/CDMA standard on their end. But during a VoLTE call, if either of them leaves LTE coverage, or if LTE signal is too weak, the call might be dropped.

Device limitations: Not all mobile devices available in the market today are VoLTE capable. Although, most new smartphones nowadays include VoLTE support.

Carrier Limitations: Only a few wireless carriers around the world have started offering VoLTE services. Even for those supporting VoLTE, carrier interoperability is limited. Some wireless carriers which offer VoLTE services only allow VoLTE calls to be made within the same carrier. That means, a person using a VoLTE capable smartphone on VoLTE supported network A, may not be able to make a VoLTE call to another person on VoLTE supported network B.

Pricing changes: Since voice and data are both transmitted as data packets, it could introduce some changes in the way operators charge for voice as well as for other data services.

In future, though, most of these limitations should be overcome. As more wireless operators support VoLTE and expand their services, we can expect seamless LTE coverage in most parts of the world over the next few years. Dropped calls won’t be an issue, and carrier interoperability will no longer be a major barrier. And you would be able to experience higher quality calls and enjoy faster downloads on your LTE network simultaneously.