Competing visions of 5G and millimetre wave
This split can be best seen in the US, where AT&T and Verizon are both about to start running trials of 5G fixed wireless access systems using the 28 GHz band in 2 to 11 cities respectively across the country, versus T-Mobile, which is launching a 5G network based on the 600 MHz band, but rolling it out nationwide.
Here in Europe, and particularly in the UK, many of the customers we’re speaking with are working to a different schedule to the US. In Europe, the emphasis for operators is in reinforcing existing 4G networks. This can be witnessed through EE winning the recent bid to provide the UK’s emergency service network. As a direct consequence of this, the company is mandated to improve coverage and quality of service (4G) right across the country. 5G is therefore seen by some as being simply more 4G coverage and this will consume operator budgets in Europe, so mmWave 5G will likely roll out between 3 and 5 years later than in the US.
That said, if the reason for rolling out 5G is to deliver fast broadband, 4G already delivers that. However, the latency (40ms +) and the quality of service is an issue. Last year saw a UK government report into the country’s networks. Akamai has already shown that the UK has the fastest data networks in Europe, but the government report elaborated on this to show that coverage is, to quote the author, Lord Adonis, “frankly appalling… our 4G network is worse than Romania and Albania, Panama and Peru.”
More specifically, the transport network is one that had been particularly neglected: “Our roads and railways can feel like digital deserts and even our city centres are plagued by not spots where connectivity is impossible. That isn’t just frustrating, it is increasingly holding British business back as more and more of our economy requires a connected workforce.”
5G, latency and roll-out challenges
5G isn’t purely about broadband speed. It is, instead about enabling new applications beyond cellular to be delivered over the network. If we look at latency, 5G is aiming at just 1ms. This reduced latency will mean it can be used in autonomous vehicles (requiring 5G communications infrastructure to become essential for the road networks), in industrial robotic control and many others where there is a critical need to minimise delay. At the very sci-fi end of the spectrum, we’ve even heard suggestions of remote surgery but this does seem somewhat far-fetched at this stage.
However, we’re still in the pre-standards phase and with two competing versions – 3GPP’s 5G NR and Verizon’s pre-5G specification. There is a real risk that the competition will make life harder for equipment developers and operators, as it did 20 years ago when DoCoMo launched a competing pre-3G specification.
This is not helped by the fact that many in the industry think the 5G NR specification is too complex, too expensive, too power demanding, and too late to be relevant for what operators want to do in 5G. But it is likely to win out. And, if the past is anything to go by, it will not be immediate, or an easy journey for the industry, hence as an IP company, Blu Wireless is preparing to support both options – aligning our road map with that of our customers’.
In the meantime, we’re seeing some looking to take a third, lower-risk option before the choice between Verizon’s and the 3GPP’s specifications is settled, taking scalable, cost effective 60 GHz mesh or star networking in conjunction with small cell-based networks.
Quality of service
This gives several benefits, not least of which is increased bandwidth – 14 GHz in the unlicensed 60 GHz V band versus 0.85 GHz for the licensed 28 GHz (being used by Verizon) and 1.6/1.4 GHz for the 37 and 39 GHz licensed bands. And while operators prefer to work with spectrum that they can own and prevent others using it (see the fight between Verizon and AT&T to acquire Straight Path, or rather its high-band spectrum assets), owning specific (licensed) bandwidth is less essential in the mmWave bands.
Propagation in these bands is low and the spectrum can be reused easily, especially with beam-forming technologies which are easier to use in these bands. Additionally, air interfaces have become smarter and can now work together – hence you can turn your Wi-Fi on in a crowded space.
All this means that quality of service can be maintained by using shared networks based on these higher frequency bands, allowing cost of deployment to drop and operators to focus on not spots – and having spent rather too long on trains from our Bristol headquarters, this would address Lord Adonis’s criticism of the networks around the transport infrastructure and concentrate it here.
About the Author
Mark Barrett is CMO of Blu Wireless Technology – www.bluwirelesstechnology.com