5.5G, AKA 5G RedCap

The Internet of Things, or IoT, was supposed to grow rapidly along with 5G as part of the ’connected world’ future it serenaded. That has not happened for many reasons and has caused the 5G industry to look at a stepping stone solution that builds on 5G but adds in what the IoT industry needs. In a word—simplicity. Full 5G is way too complex and power-hungry to fit into a smart watch or similar. Enter 5.5G.

By Johnnie Denton

Johnnie Denton is the editor of The Advisor, a researcher, and oversees TMC benchmarking studies.

The Internet of Things

IoT is basically about ‘devices’ that need to connect to a back-haul data network wherever they are. Wearable devices, like Smart Watches, are clever but not stand-alone. They work via the user’s cellphone using Bluetooth. The main link comes from the cellphone. The IoT ‘Holy Grail’ is for a similar sized device to be fully self contained. Then we can develop healthcare assets, environment monitors, fleet and asset management tools and more flexible smart home systems.

Present Generation IoT

Devices do exist that can connect to external data networks. Many Smart Home systems will connect to WiFi in order to access the Internet. These include everything from CCTV cameras to washing machines. Some can move outside and connect via 3G networks at slow speed (under 20Mbps). Some medical devices can connect back to their supplier such that the prescribing physician can monitor performance and potentially adjust settings without the need for the patient to attend in person.

IoT Cellular Mismatch

Peter’s article earlier in this issue shows how cellular has evolved to be faster and more powerful with each new generation. All these developments add complexity and consume battery power. Neither are desirable for IoT devices, which aim to be small and low powered. A Formula 1 turbo-charged engine is not very practical for an aerial drone.

One of the aims of 5G technology is to provide a go-anywhere connection to the Internet and that is what IoT devices need. IoT does not need the ultra high speeds offered by 5G, but it does need to ‘move with the times’. That means working with 5G.

Enter RedCap

The favoured solution is to introduce a new ‘device category’ into the 5G world, called ‘New Radio Reduced Capacity’ (or RedCap). Now, small devices that work on WiFi and legacy 3G will be able to move up to the 5G ecosystem.

The beauty of 5G is that the network is largely software defined and hence easy to upgrade. RedCap is simply a feature in the latest incarnation of the 5G spec, known as Release 17. Although 5G RedCap is sometimes represented as ‘5.5G’ it is not an ‘upgrade’ that main stream 5G users will be aware of or need.

Invisible Transition

It is not something that end users need to be aware of. New IoT devices will simply contain the new hardware and will work over 5G networks.

IoT devices need to be configured to work over a user’s WiFi network. They will also need to be configured for 5G—possibly by the user, or perhaps by the supplier. Time will tell as the technology matures.

IoT Data Plans?

As IoT devices start to leverage their new-found internet freedom, we will see vastly higher numbers of connections to cell sites. How the bandwidth used is paid for is the next challenge. We assume that we’ll see new data plans specifically for IoT, perhaps charging by the number of devices in a plan.

If you’d like to discuss how your network operations need to change to include IoT and 5G or to comment on this article, please email me at johnnie.