5G RedCap Router: Reduced Capability 5G for IoT and Industry

RedCap exists because full 5G is expensive. A full 5G modem has four receive paths, supports wide channels and many band combinations, and draws a fair amount of power. That is great for a router serving an office. It is silly for a router connecting a vending machine. Until RedCap, the choice for those devices was 4G, which is fine today but sits on a network that will eventually be reshaped around 5G.

RedCap fills the gap. It gives device makers a 5G option with a cost and power profile much closer to 4G Cat 4 than to full 5G.

What gets cut, and why

Reduced capability is a fair description. Compared with a full 5G device, a Release 17 RedCap device typically has:

• a maximum channel bandwidth of 20 MHz in the bands used for most 5G, rather than up to 100 MHz
• one or two receive antennas rather than four
• simpler modulation in some configurations
• limited or no carrier aggregation
• half duplex operation allowed in some bands, which simplifies the radio

Each of those cuts reduces chip cost, board complexity and power draw. Fewer antennas also means smaller devices and simpler installation. The result is peak speeds that are modest by 5G standards but entirely adequate for most connected equipment.

RedCap needs standalone 5G

This is the most important practical point. RedCap devices only work on 5G standalone networks. They cannot use the NSA 5G that most phones still connect to. If a site has no SA coverage, or your SIM is not enabled for SA, a RedCap-only device will fall back to 4G if it has a 4G mode, or not connect at all if it does not.

Most RedCap modules and routers on the market include 4G fallback, which is sensible. Check this before buying, because a RedCap device without LTE fallback is a bet that SA coverage will be there everywhere you install it. Our 5G SA router guide explains how to check SA at a site.

Where RedCap makes sense

Industrial gateways. Remote monitoring, PLC access and SCADA polling need reliability and remote management, not hundreds of megabits. RedCap provides 5G network longevity at a price and power level suited to industrial work.

Backup connections. For a small site where the backup just needs to keep tills, VoIP and email running during a fixed line fault, RedCap speeds are ample.

Video at modest resolution. A couple of security cameras streaming at sensible bitrates can run over RedCap, although sustained upload is the limiting factor. For more cameras or higher resolution, full 5G is safer. See our CCTV guide.

Wearables and handheld devices. Outside routers, RedCap is designed for smartwatches, body cameras, medical wearables and industrial handhelds.

Energy and EV charging. Chargers, battery storage systems and smart grid equipment need dependable connectivity for many years. RedCap is a natural fit, especially as these systems are increasingly expected to support remote control and software updates.

Where it does not

RedCap is the wrong choice if you need router speeds comparable to fixed broadband, if you are serving lots of users, or if the site has no SA coverage and no prospect of it soon. It is also not a replacement for the low power wide area technologies, LTE-M and NB-IoT, for very small battery devices that send a few bytes a day. Those remain cheaper and lower power for that job.

eRedCap: the next step down

Release 18 introduces enhanced RedCap, often written eRedCap. It reduces the bandwidth further, to around 5 MHz for the data channels, with peak speeds around 10 Mbps. That positions it closer to 4G Cat 1, aimed at devices that need even lower cost and power than RedCap while staying on 5G.

For routers, Release 17 RedCap is the relevant technology now. eRedCap will matter more for sensors, trackers and small embedded devices as chipsets arrive. Over time, the combination of RedCap and eRedCap is expected to take on much of the role that 4G Cat 1 and Cat 4 play today.

Antennas for RedCap routers

Because RedCap devices use one or two receive paths, they are less able to compensate for a weak signal than a four-antenna full 5G router. That makes antenna placement more important, not less. If the router is in a cabinet or an indoor plant room, an external antenna is usually worth it. Two-port MIMO antennas suit two-receive RedCap devices well.

The same frequency considerations apply as for any 5G device. RedCap will often run on mid band 5G, where building penetration is poor, or on lower bands if the network uses them for SA. See the 5G antenna guide for more on this.

SIMs and tariffs for RedCap

RedCap devices need a SIM and tariff that allow access to the SA core network. Some networks treat RedCap as a separate device category, so also check that the SIM provider supports RedCap devices specifically, not just SA phones. For multi-network IoT SIMs, ask which of the partner networks support RedCap on SA and in which areas.

Data use on a RedCap router is typically modest, so standard IoT tariffs usually fit. The higher cost is often in engineering time during early deployments while you confirm coverage and compatibility.

Is RedCap ready?

The honest answer is that it depends where you are and what you need. The chipsets exist, RedCap routers and modules are shipping, and UK networks have been building SA coverage. But SA availability and RedCap support on SIMs still vary. For a pilot or a small rollout in areas with known SA coverage, RedCap is a reasonable choice now. For a nationwide deployment where some sites are rural, a RedCap device with solid 4G fallback, or a full 5G router, is the safer bet today.

What makes RedCap attractive is the long view. Equipment that goes into infrastructure tends to stay there for ten years or more. A RedCap device bought now should still be on a supported network well into the 2030s, which is harder to guarantee for 4G-only hardware.

How RedCap compares with the other low cost options

It helps to see RedCap alongside the technologies it sits between. These are rough positions rather than precise figures, because real performance depends heavily on coverage.

The pattern is clear when you lay it out. RedCap is not trying to compete with full 5G on speed. It is the 5G answer for the large middle of the market that currently runs on 4G Cat 4 and similar.

Planning a RedCap pilot

If you want to try RedCap, a small structured pilot will tell you far more than a datasheet. Pick a handful of sites that represent your estate: one urban, one suburban, one rural and one awkward indoor location. Use the SIM you would actually deploy. Run each router in its normal configuration for at least a few weeks, and log which network mode it spends its time on, along with signal levels and any drops.

At the end you will know whether SA coverage is good enough where you need it, whether the 4G fallback behaves sensibly, and whether the speeds suit the application. You will also find out how the router’s management platform reports RedCap connections, which is surprisingly variable between manufacturers.

Keep a full 5G or good 4G router in the pilot as a control. Without a comparison it is hard to tell whether a slow result is down to RedCap, the site or the network on the day.

Questions to ask a RedCap router supplier

• Is this Release 17 RedCap, and does the module support two receive antennas?
• Which 5G bands are supported in SA mode?
• Does it fall back to 4G, and to which LTE category?
• Has it been tested on UK SA networks, and which ones?
• What is the typical and peak power draw?
• How long will firmware and modem updates be provided?

If you are weighing up RedCap against full 5G or 4G for a project, email sales@5grouter.co.uk and we can talk it through.