US operators T-Mobile, Verizon and AT&T are preparing to deploy standalone 5G (SA 5G) in 2020. This is an aggressive timeline considering the operators are still very early in their launches of non-standalone 5G (NSA 5G), which is considered a stepping stone to SA 5G.
Operating a standalone 5G network has always been the ultimate goal of US operators because SA 5G promises faster speeds, lower latency and will make new features such as network slicing possible.
Unlike non-standalone 5G, SA 5G networks are not dependent on an operator's 4G LTE network. In fact, what makes a SA 5G network faster and more efficient is that it uses a 5G core network, which is a simpler architecture with a separate user plane and control plane and high-bit rate provisioning.
But does this move to SA 5G signal the end of 4G? 4G has been around for nine years -- Verizon launched the first large-scale LTE network in December 2010. Historically, most wireless air interface technologies have a lifespan of about eight to ten years. 2G technologies -- CDMA and GSM -- made their debut in the US around 1996. 3G technologies UMTS and CDMA launched in the US around 2004 and 2005.
Verizon has said it intends to sunset its 3G network at the end of 2020 and will use that 3G spectrum for 5G. Likewise AT&T has said that it plans to sunset its 3G network in early 2022. T-Mobile and Sprint haven't been as forthcoming with their plans, most likely because they are in the midst of a merger and are waiting for it to close.
Not surprisingly, operators are focusing most of their network capital expenditures on 5G technology instead of 4G. "There is a desire to not spend more on 4G," says Michael Murphy, CTO of the Americas for Nokia. "[Operators] would rather spend it on 5G core."
However, just because money isn't flowing toward 4G it doesn't mean the end is near. "LTE will be around for a long period," says Paul Challoner, VP of product solutions for Ericsson North America. "There will be another decade of LTE in North America."
According to Ericsson's November 2019 Mobility Report, LTE is still growing globally. As of the third quarter there were 4.2 billion LTE subscriptions around the globe. By 2022, when LTE hits its peak, Ericsson expects there to be 5.4 billion LTE subscriptions globally. After that Ericsson believes LTE will decline to about 4.8 billion subscriptions by the end of 2025 as more wireless customers migrate to 5G networks.
In the US market, 4G will likely decline more rapidly than the rest of the world because 5G penetration in North America is expected to be higher than other regions.
But the speed that customers switch from LTE devices to 5G devices will play a key role. "Historically the churn rate of people getting new devices has been pretty consistent," says Nokia's Murphy. "About 20% of people update their mobile phones every year. And in the beginning 5G devices are expensive."
Murphy adds that by year-end 2020 there should be more 5G devices with a variety of price points. Plus, Apple is expected to launch its 5G iPhone in late 2020, which will likely appeal to US subscribers.
But even as 5G is gaining traction, there are still US subscribers who own 3G devices.
"Some don't want to buy a new device," Ericsson's Challoner says, adding that many of the 3G subscriptions are M2M customers that have long-term contracts.
Another reason LTE networks won't disappear quickly is because of voice services. Currently voice-over-LTE (VoLTE) is the foundation for voice calling on 5G devices. Ericsson's Mobility Report says there are 2,500 VoLTE-enabled device models and about 2.1 billion VoLTE customers.
Challoner said that voice-over-New-Radio (NR) for 5G is currently at the trial stage but it will take some time for voice-over-5G-NR devices to gain traction in the market. "Voice-over-NR needs to play out because voice support is how you move from one generation of technology to the next," he says.
Thus, 5G may be where US operators are focusing their attention (and their money) but 4G networks will continue to be a mainstay in the US for many years to come.
— Sue Marek, special to Light Reading. Follow her @suemarek.