5G RedCap: What is it? What is its Purpose? And What Applications Does It Support?

5G, the de facto standard for high-speed broadband cellular communications, continues to grow in popularity. As 5G soars, other technologies decline. In the US, 2G networks have largely been sunset; the same is true for 3G, with the major carriers having already phased out their 3G networks or phasing out these networks. 4G is in a different spot as these networks are still widely available, providing high-speed connectivity and reduced latency to business and consumer Internet of Things (IoT) applications like alarms and smart homes. Nevertheless, the ascendance of 5G means that the 4G sunset is approaching. Many experts predict the 4G sunset will occur in 2030 or sometime after.

Amid 5G’s rise, proliferation and inevitable replacement of 4G, it is important to note that there is diversity within this transformative technology, specifically Reduced Capability 5G New Radio (NR) or 5G RedCap. This new class of 5G is, as the acronym implies, a reduced-capability version of 5G, which will help organizations fill a 5G device class for mid-speed use cases, save money and future-proof IoT deployments to avoid disruption. Launched in mid-2022, the 3rd generation partnership project (3GPP) Release (Rel) 17 introduced 5G RedCap as the 5G NR replacement of 4G LTE Category (Cat) 4. This article will dive into 5G RedCap and its distinctions from 5G, discuss the connectivity gap it fills, and cover some exciting new use cases. 

What is 5G RedCap, and How Does it Differ from Standard 5G?

5G RedCap is the first 5G Standalone (SA)-only technology in that it runs purely on a 5G radio and connects to a 5G core network. It offers a range of power-saving functionalities, making it more power-efficient than the 4G variant. Concerning speed, 5G RedCap throughput is equivalent to the mid-speed LTE 4G Cat 4 – more specifically, around 150 megabits per second (Mbps) downlink and 50 Mbps uplink. For bandwidth, 5G RedCap operates with a maximum bandwidth of 20 MHz, significantly less than the 100 MHz plus bandwidth of standard 5G. It also supports 4G fallback when a 5G signal cannot be found. Moreover, 5G RedCap has all 5G’s security capabilities. 

Another key distinction between 5G RedCap and standard 5G is that 5G RedCap devices have simpler radio and modem designs and operate on narrower bandwidths. Specifically, 5G mobile broadband or enhanced mobile broadband (eMBB) devices need at least four antennas, but a 5G RedCap device only needs one or two antennas. Imagine a highway with multiple lanes: standard 5G could handle high traffic on all the lanes simultaneously via techniques like wider channel bandwidth and carrier aggregation. 5G RedCap, however, because of its narrower channel bandwidth, could only handle traffic on one lane and at a lower speed in a limited manner. Additionally, Rel 15 and 16 introduced two- and four-way MIMO (multiple input, multiple output) for eMBB. In Rel 16, there was even more carrier aggregation and MIMO combinations. But because 5G Redcap only has two receive antennas and one transmit antenna, it is only possible to do two-by-two MIMO on the receive – there is no capability for four-by-four MIMO.

While 5G RedCap is limited in speed, it’s still power-efficient and offers cost-conscious 5G designs. Recall that 5G RedCap devices have simpler radio and modem designs and operate on narrower bandwidths, making them less complex and costly than regular 5G devices. For the longest time, one of the chief complaints in the industry was that new eMBB products were expensive. Of course, the price of 5G devices will decrease as ubiquity increases – however, in the meantime, 5G RedCap was introduced to serve as an efficient, lower-cost alternative. Put simply, 5G RedCap was born out of the idea that there should be reduced capability 5G that can serve the market segment that does not require the high data rates of eMBB nor afford to pay the high price for eMBB.

Another important distinction must be made between 5G RedCap and eRedCap or enhanced Reduced Capability. Rel 18 launched eRedCap as a version of NR that will further simplify complexity with even more reduced performance equivalent to Cat 1 Bis, driving costs down and scaling up volume considerably. 5G RedCap and eRedCap are two different device types created by throughput reduction. Also, note that the “e” in eRedCap does not stand for “evolution,” which is a common misconception. From a technical perspective, eRedCap and RedCap are relevantly similar, with both having the same bandwidth, single antenna option, extended power saving options and dependency on 5G SA networks. However, eRedCap speeds are lower than RedCap but closer to LTE Cat 1, with a throughput of 10 Mbps downlink and 5 Mbps uplink. 

5G RedCap and the Mid-Speed Connectivity Gap

5G RedCap addresses a broad, heterogeneous market, especially in IoT, where it provides a 5G device class for mid-speed use cases, filling the mid-speed gap. This mid-speed gap refers to the numerous applications that don’t fit neatly into the initial 5G International Telecommunication Union (ITU) services, which include eMBB, Ultra Reliable Low Latency Communications (URLLC) and massive machine-type communications (mMTC). 

Of the three 5G ITU services, eMBB represents the highest throughput, supporting use cases like smartphones, gaming, gateways, computing, VR/AR/XR and car infotainment. URLLC is perfect for applications that require low latency and reliability, like autonomous vehicles, public services, V2X, UAV, rail, and industrial and critical infrastructure. Lastly, mMTC is ideal for use cases where energy efficiency is crucial, like tracking, sensors, simple metering, agriculture and infrastructure (lighting). Despite covering a broad swath of applications, the three 5G ITU services do not cover those IoT use cases requiring mid-speeds.

5G RedCap will fill the mid-speed connectivity gap by enabling new IoT use cases that require low latency and better power efficiency but don’t require the ultrahigh-speed or ultralow latency of 5G NR. Likewise, 5G RedCap is great for applications where reasonable throughput is needed to support data flow for next-generation applications. Some examples of these mid-speed applications include logistics, smart homes, machinery, industrial cameras, metering, smart wearable technology, industrial sensors, vending, wireless video surveillance, eHealth and alarms. Not only will 5G RedCap fill the mid-speed gap, but it will also (thanks to Rel 18) bring beneficial 5G features like better latency and power consumption performance to devices in the mMTC class.

Furthermore, 5G RedCap gives these mid-speed IoT devices the flexibility to transition from LTE 4G to 5G so that they can have greater longevity and extend their usefulness in the field. It is worth noting that dynamic spectrum sharing (DSS) will play a key role in this transition from 4G to 5G, permitting the same network to communicate concurrently with 4G or 5G devices. DSS also enables end devices to shift to 5G at the end of their natural life cycles. Ultimately, every class of connectivity in 4G must transition to 5G, and those devices in the mid-speed connectivity segment are no exception.

5G RedCap Use Cases

An Omdia report forecasts that 5G RedCap will surge by 66% CAGR to reach 963.5 million connections by 2030, highlighting the growing influence of 5G technology on IoT use cases and the industry’s growing readiness for RedCap and eRedCap solutions. For example, body cameras worn by first responders and other public safety personnel will leverage 5G RedCap as it provides low latency and power efficiency, features that are critical for broadcasting live video (footage can also get stored locally and downloaded once the wearer returns from the field). 5G RedCap also gives body cameras 4G backup capabilities. From a design perspective, 5G RedCap uses a small form factor, making it more practical than a larger mobile broadband 5G device.

As discussed above with the mid-speed device class, 5G RedCap enables new IoT use cases like video telematics, alarm systems, precision farming, renewable energy monitoring and EV charging. Another is remote patient monitoring via wearable medical devices. A patient wears a device, such as a glucose monitor, that reads, monitors and transmits data in real-time to their healthcare provider. These devices require affordable, mid-speed throughput with guaranteed longevity, making 5G RedCap an optimal choice. 5G RedCap is also ideal for private 5G networks, where efficiency and cost-effectiveness are crucial. Some examples of private 5G use cases include plain old telephone services or POTS replacement, mining and port data communications for large shipping ports. 5G RedCap is a particularly suitable product for POTS replacement as these old systems continue to be substituted with wireless technology. In terms of private and secure networking, a use case where 5G RedCap is gaining popularity is in connected machinery, where smart machines communicate with other smart machines within the walls of a factory.

Additionally, 5G RedCap utilizes the network slicing capabilities of 5G SA networks. Network slicing is the creation of multiple virtual networks on top of a shared physical infrastructure, each with tailored configurations. An operator can allocate specific network resources, like bandwidth and latency, to different IoT applications based on quality-of-service class, giving preference and priorities to mission-critical applications. For example, IoT wearable medical devices used for real-time patient monitoring will have a dedicated slice with guaranteed latency and reliability for data transfer to healthcare providers. This slice will always have priority over, for example, a consumer smartphone streaming video. Network slicing also enables networks to preemptively react to critical situations by dynamically assigning resources from less-important slices to mission-critical ones. The organizational elasticity of network slicing likewise helps network architects save money and time as it simplifies their deployment strategies and solutions.

Finding a Partner to Facilitate the Transition to 5G

3GPP Rel 18 is here, marking the first release of 5G-Advanced. With the telecommunications industry embracing 5G-Advanced, it is paramount that organizations prepare for the imminent arrival of these new features and changes to future-proof their IoT deployments – especially those applications in need of efficient, mid-speed connectivity. Businesses need a technical partner with 5G and 5G RedCap competencies and experience to help transition their products from aging standards. Moreover, companies should prioritize those partners that are more than hardware providers but IoT enablers. Such a partner will not only offer 5G modules and data cards but support the entire IoT lifecycle through its connectivity plans, platforms and end-to-end security.