More on 5G Standards

I wrote a blog last week about the new 5G standard being developed by the International Telecommunications Union (ITU). This standard is expected to be passed this November. However this standard is not the end of the standards process, but rather the beginning. The ITU IMT-2020 standard defines the large targets that define a fully developed 5G product. Basically it’s the wish list and a fully-compliant 5G product will meet the full standard.

But within 5G there are already a number of specific use cases for 5G that are being developed. The most immediate three are enBB (enhanced mobile broadband, or better functioning cellphones), URLLC (ultra-low latency communications to enhance data connectivity) and mMTC (massive machine type communications, to communicate with hordes of IoT devices). Each use case requires a unique set of standards to define how those parts of the 5G network will operate. And there will be other use cases.

The primary body working on these underlying standards is the 3GPP (3rd Generation Partnership Project). This group brings together seven other standards bodies – ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC – which demonstrates how complicated it is to develop a new wireless technology that will be accepted worldwide. I could talk about what each group does, but that would take a whole blog. Each standards group looks at specific aspects of radio communications such as the modulating schemes to be used, or the format of information to be passed so that devices can talk to each other. But the involvement of this many different standards groups explains a bit about why it takes so long to go from a new technology concept like 5G to functioning wireless products.

There is currently a lot work being done to create the specific standards for different portions of a 5G network. This includes the Radio Access Network (RAN), Services and System Aspects (SA) and Core Network and Terminals (CT).

The 5G RAN group, which looks at radio architecture, began work in 2015. Their first phase of work (referred to as Release 15) is looking at both the eMBB and the URLCC use cases. The goal is to define the specific architecture and feature set that is needed to meet the 5G specification. This first phase is expected to be finished in the fourth quarter of 2018. The 5G RAN group is also working on Release 16, which looks more specifically at getting radios that can comply with all of the aspects of IMT-2020 and is targeted to be completed in December of 2019.

The 5G SA group has already been actively working on the services and systems aspects of 5G. The preliminary work from this group was finished last year and final approval of their phase 1 work was just approved at the Mobile World Congress. But the SA group and the RAN group worked independently and it’s expected that there will be work to be done at the end of each phase of the RAN group to bring the two groups into sync.

The work on the core network has begun with some preliminary testing and concepts, but most of their work can’t be started until the RAN group finishes its work in 2018 and 2019.

The reason I am writing about this is to demonstrate the roadblocks that still remain to rolling out any actual 5G products. Manufacturers will not commit to making any mass-produced hardware until they are sure it’s going to be compatible with all parts of the 5G network. And it doesn’t look like any real work can be done in that area until about 2020.

Meanwhile there is a lot of talk from AT&T, Verizon and numerous vendors about 5G trials, and these press releases always make it sound like 5G products will quickly follow these trials. But for the most part these trials are breadboard tests of some of the concepts of the 5G architecture. These tests provide valuable feedback on problems developed in the field and on what works and doesn’t work.

And these companies are also making 5G claims about some technologies that aren’t really 5G yet. Most of the press releases these days are talking about point-to-point or point-to-multipoint radios using millimeter wave frequencies. But in many cases these technologies have been around for a number of years and the ‘tests’ are attempts to use some of the 5G concepts to goose more bandwidth out of existing technology.

And that’s not a bad thing. AT&T, Verizon, Google and Starry, among others, are looking for ways to use high-bandwidth wireless technologies in the last mile. But as you can see by the progress of the standards groups defining 5G, the radios we see in the next few years are not going to be 5G radios, no matter what the marketing departments of those companies call them.