The 6 GHz band is on a good course to become the latest and, in many countries, the largest unlicensed band available, giving Wi-Fi and other technologies such as 5G NR-U an unprecedented spectrum base for expansion.
After the release of the 6 GHz band for unlicensed use in April in the US, the UK and South Korea have also opened the band. Many other countries are working towards this, with Europe expected to open the band in the coming spring and Brazil leading the efforts in Latin America.
Why should we care?
What is most notable about the 6 GHz band is that with its 1,200 MHz it is the largest allocation of unlicensed spectrum in the US and South Korea, (in the UK.and Europe the band will be a more modest, but still substantial 500 MHz).
For context, in the US, Wi-Fi currently operates in almost 800 MHz in the 2.4 GHz and 5 GHz bands; 6 GHz will more than double the spectrum available to Wi-Fi to 2,000 MHz. Even taking into account some restrictions in the use of the band to protect access for incumbent users primarily in outdoor environments and the transmit power limitations, it is still a lot of new bandwidth available that is open not only to residential and enterprise users, but also to operators. Verizon is one of the US operators currently testing 6 GHz equipment.
An attention deficit?
Yet, surprisingly, the 6 GHz band is not attracting as much attention as other bands, if we were to judge by Google search statistics. It may be that this is still quite new and commercial products have been announced and will be available in a matter of months, but they are not yet here. But then the hype on 5G started well before we even knew what it was about – and certainly before it became a commercial reality.
I would venture that the lower media noise and search activity may be due to the fact that we have a good understanding of what it means to have a new unlicensed band and how commercial deployments will happen: gradually as equipment becomes available, incrementally added to expand the capacity and performance of the existing infrastructure if using Wi-Fi. 6 GHz may lack the drama of 5G, but this does not diminish the impact that 6 GHz will have across the board – from consumer users, to enterprises and to service providers – especially as it becomes available in more countries.
Do we need more unlicensed spectrum?
Of course, more spectrum is always welcome. But do we need more unlicensed spectrum? Should the 6 GHz band be allocated, at least partly, for licensed use? There has been much debate about this but the decision to open the band only to unlicensed use is a wise one, especially in countries like the US where there are already incumbent users with priority access to the band which limit the control licensees would have on the band.
But more importantly, we do need more unlicensed spectrum. Wi-Fi carries almost 50% of IP traffic according to Cisco’s VNI and most of wireless access (in many countries up to or above 80% of wireless traffic, and this is unlikely to change over the next few years even as 5G access grows), making the unlicensed bands the most intensely used.
With the higher traffic loads and reliance in wireless access, the existing unlicensed spectrum is no longer sufficient. During the COVID-19 pandemic, unlicensed access became even more precious to our lives. Most of the increase in traffic was over Wi-Fi (Comcast saw a 36% increase in Wi-Fi traffic and a 17% decrease in LTE traffic on Xfinity Mobile in May 2020), not over cellular, as people spent more time at home.
Stronger enterprise private networks
We can all use more bandwidths at home, especially as wired Ethernet through the house is going out of fashion and we expect everything in the house to attach to our Wi-Fi wireless networks. However, enterprises will benefit more directly from adding 6 GHz to their wireless networks – either Wi-Fi or, starting now, CBRS. 6 GHz allows enterprises to run applications that require high bandwidth and better reliability (i.e., less contention and interference) than they can expect in the crowded 2.4 GHz and 5 GHz bands.
Similarly, in enterprise private networks 6 GHz is going to be a powerful complement to CBRS in the US and localized spectrum allocations in countries like Germany and the UK These mid-band channels available to the enterprises are well suited to applications that require high reliability and control over transmission, but have less bandwidth (the CBRS band is 150 MHz compared to the 1,200 MHz of 6 GHz in the US).
Will 5G NR-U win over Wi-Fi?
We often equate unlicensed with Wi-Fi, for the simple reason that it is ubiquitous in our devices and our environment. But unlicensed access is technology neutral and other technologies (e.g., Bluetooth and even LTE with LAA in mobile operators’ networks) coexist (or compete) with Wi-Fi in unlicensed bands.
With the growing push for 5G NR-U – the 5G for unlicensed bands – Wi-Fi will face a stronger competition in the 6 GHz band. Unlike the 2.4 GHz and the 5 GHz, Wi-Fi does not have an existing dominant position in 6 GHz. Residential and enterprise users will be able to choose between Wi-Fi and 5G without having to stick to Wi-Fi to support existing devices.
So, what will people, enterprises and service providers pick, Wi-Fi – the version of Wi-Fi 6 for the 6 GHz band – or 5G? This is a critical open question for the long term. Wi-Fi and 3GPP technologies are converging from a technology perspective and, while they address different connectivity needs, their performance is getting more and more similar.
Will we eventually need two main access technologies, or would one be sufficient and reduce the complexity? As much as interoperability and shared access is valuable, having two technologies adds an element of healthy competition and reduces complacency.
In the short term, however, it is difficult to see how 5G could displace or cut down the role of Wi-Fi in all licensed bands, including the 6 GHz band. Many people may complain about Wi-Fi connectivity, but that is mostly due to its success: too many people use it, and spectrum and infrastructure are limited resources.
But I still have yet to meet anybody that plans to give up Wi-Fi entirely, even if equipped with the latest 5G phone. The cost to transition from Wi-Fi to 5G in unlicensed band in the short term is too high and the performance benefits too small to justify a big market shift to 5G in the short term.
There will definitely be use cases for 5G NR-U in the 6 GHz band and we should expect the use of 5G NR-U to grow with time, especially in deployments driven by mobile operators, but it is not time yet to ditch our Wi-Fi access points or to go for a phone without Wi-Fi, if it exists.
But the good news is that in the 6 GHz band, there will be room for both technologies to grow and fight it out – in their current incarnations, or most likely in their future ones with 6G and Wi-Fi 7.