As data traffic continues to grow every day, so too does the need to increase capacity within telecommunication networks. In order to do this MNO’s (Mobile Network Operators) need to look to acquire new spectrum or alternatively, make available more space on existing bands. It is this need for spectral efficiency that has driven the development of mobile generations from 1G to 5G.
So, as we develop new generations of technologies and infrastructure, with improved spectral efficiency, data rates and strength of service, why are we still using 2G and 3G technologies?
4G offers up to six times better spectral efficiency that 3G, because it combines advanced techniques with new technologies (such as MIMO, Massive-MIMO and higher modulation) to improve the amount of data it can send on each hertz of spectrum.
So why don’t operators just switch off their 2G and 3G networks, create revenue from the equipment before it becomes invaluable and move all their systems to 4G to gain higher spectral efficiency?
Many customers still require the services that 3G infrastructure provides. Although the numbers may have reduced, operators can’t just leave them behind and expect them to upgrade their systems without proper phasing out of the services.
You may not be aware but standard 4G services don’t support voice-calls, which are a fundamental service for a mobile customer. Instead, a voice call will be transferred to 3G services using a system call CSFB (Circuit Switch Fallback) and although many operators are beginning to introduce technologies like VoLTE (Voice over LTE) to support calls on 4G, it will take a while before this is fully available to everyone, so in the meantime 3G services need to still be provided.
It may seem counter intuitive, but 2G services may actually outlast 3G services in some cases. That’s because the so many legacy services are still reliant on 2G and wouldn’t make much sense to transfer to 3G or 4G.
For example, many machine-to-machine technologies like vending machines and credit card machines largely use the GSM services that 2G provides to send alerts, text messages and data to record transactions and billing.
The phasing out of 2G will take a lot longer as operators look to make the best use of the different generations of technologies and manage their spectrum availability accordingly. It all comes down to reasonable demand. If enough people continue to require legacy services, then it is up to the operators to adapt accordingly.
Some operators have chosen to phase 2G out already, for example all of Japans cellular operators abandoned 2G services in favour of 3G and 4G by April 2012 with others following suit in the very near future, but for those MNO’s that haven’t upgraded to newer technologies such as VoLTE, they will need to continue to develop way to allow customers to seamlessly move between multiple technologies (for example using 4G to check emails, 2G for SMS and 3G for phone calls) in order to offer them the best customer experience.
When do you think we can expect to see a world that no longer supports 2G and 3G services completely?