Summary Bullets:
- Both 4G and 5G will co-evolve in mobile operator networks for years.
- Even standalone 5G will coexist alongside 4G/5G networks, as operators further monetize 4G investments.
For some time now, the telecom industry has been heralding the dawn of the 5G era, the time when operators are deploying 5G networks and launching 5G services. But, it would be more accurate to say we’re at the dawn of the 4G/5G era, as this is what operators are actually deploying. Both technologies will co-evolve in operator networks for years. And as operators ramp up 5G network investment, they can’t neglect LTE.
To stay ahead of (or keep up with) their competitors, operators will need to be proactive in rolling out 5G. Getting a jump on 5G means rolling out the first version of 5G technology, known as non-standalone 5G, which relies on an LTE packet core. Standalone 5G, which doesn’t need an LTE core, will come later. But, many operators – South Korea’s SK Telecom is an example – will continue expanding their non-standalone 4G/5G networks even as they later roll out standalone 5G. The good news for operators is that this allows them to extend the life of their existing LTE networks and enjoy more return on those investments.
There are other forces sustaining the lifespan of 4G. Some 5G services will be rolled out over high-frequency spectrum. Those high frequencies have shorter ranges, requiring operators to deploy small cells on light poles and other hard-to-reach places, a task they’ve learned over the years isn’t easy or cheap. To maintain broad coverage over wide areas, they’ll need to rely on their existing LTE macrocells. In addition, it will take time for 5G-compatible devices to spread among mobile subscribers, and in the meantime, many subscribers will rely on LTE service.
Operators are also no doubt eager to mine the enterprise and IoT use cases that 5G has promised. But many of the technologies needed to deliver them – such as ultra-reliable, low-latency communications – will take time to develop, commercialize, and perfect. In the meantime, many enterprise and IoT use cases can be served by LTE, which is familiar and well understood today and becoming less expensive as it becomes more mature. In fact, as 5G hype pervades the public consciousness, it may be useful in sparking discussions between enterprises and operators (or RAN vendors) that lead to LTE investments, because in many cases, the operator will tell the enterprise that what they want from 5G can be accomplished with LTE, only sooner (and perhaps cheaper).
More good news for operators: Network equipment suppliers, in recognition of the need for 4G/5G co-evolution, have introduced several solutions for aiding this trend. Some solutions allow operators to add 5G radios to existing 4G cell sites without occupying additional pole attachments (see ZTE’s UniSite or Huawei’s Super Blade Site); this is important because extra pole space may be unavailable in many places, and where it is available, it will increase expenses. Increasingly, vendors are also offering dual-band and triple-band radios to accommodate 4G and 5G in the same box. In addition, some RAN software solutions allow 4G and 5G traffic to be delivered using the same spectrum, giving operators flexibility in co-evolving the two technologies and migrating one to the other over time (see ZTE’s Magic Radio Pro, Huawei’s CloudAIR, or Ericsson’s Dynamic Spectrum Sharing).
Going forward, operators are likely to talk less and less about 4G as they try to stir public demand for 5G. But 4G will remain a silent, steady workhorse, enabling the industry to achieve many of its 5G ambitions.