5G RedCap

What is 5G RedCap?

RedCap is a variation of 5G technology created by enhancements in 3GPP Release 17. RedCap enables Internet of Things (IoT) devices with reduced capabilities to connect to the internet via 5G networks. These RedCap devices are less complex, less costly, and more power efficient than conventional 5G devices like smartphones. However, they do not require the full capabilities and performance enabled by the 5G New Radio (NR) standard.

What types of devices use 5G RedCap?

5G RedCap addresses applications for simpler and lower-cost IoT devices such as sensors and actuators that send small packets of information continuously and require a long battery life. Such applications do not fit neatly into any initial use cases defined by the 5G NR standard. Release 17 specifies three RedCap use cases: industrial wireless sensors, health wearables, and surveillance devices.

Each RedCap use case has its own requirements for maximum data rate, end-to-end latency, and service availability. Early adopters of RedCap include chipset manufacturers and makers of IoT products that fit into the wearables, sensors, and surveillance use cases.

What are the key benefits of 5G RedCap?

5G RedCap devices use fewer antennas and support lower bandwidths than conventional 5G user equipment such as smartphones. Fewer antennas and multiple-input / multiple-output (MIMO) layers reduce device cost. Lower bandwidths reduce power amplifier costs.

RedCap provides other enhancements that further reduce the cost of RedCap devices. For example, RedCap supports half-duplex frequency division duplex (FDD), a transmission mode that can significantly affect device cost. Half-duplex FDD prevents the device from transmitting and receiving data on different frequencies at the same time. As a result, RedCap devices can use switches instead of expensive duplexers.

Fewer antennas, lower bandwidths, and different modes of operation also help reduce power consumption. RedCap devices can transmit data without connecting to the network and have less stringent radio resource management requirements than other 5G devices, helping the device save energy.

What are the limitations of 5G RedCap devices?

Because RedCap devices have fewer antennas and support lower bandwidths, they lack the full throughput, latency, and frequency-range capabilities of conventional 5G devices. 5G RedCap devices only support 2x2 MIMO for the downlink and single-input/single-output for the uplink, and bandwidths of 20 MHz for frequencies below 7.125 GHz and 100 MHz for millimeter-wave frequencies.

The lower bandwidths of RedCap operation require changes in bandwidth part configurations for both the downlink and the uplink. New information elements enable the bandwidth to adapt dynamically to the device’s actions.

5G RedCap devices require specialized signaling parameters and procedures. RedCap devices use a different random-access channel procedure to access the network, which affects device compatibility.

5G RedCap devices also do not detect scheduling information for the downlink and the uplink in the same set of symbols. As a result, they cannot check messages in the downlink while in uplink mode or send information in the uplink while monitoring the downlink.

When will 5G RedCap devices be available?

The first 5G RedCap chipsets will be available in 2023 and 2024, with commercial RedCap devices entering the market in 2025 and 2026. After 2026, the growth of commercial RedCap devices should rise steeply. Industries and consumers will adopt 5G-connected wearables for health monitoring and other applications, low-cost wireless sensors for industrial data collection and asset-tracking, and surveillance devices for use in smart cities, factories, and other applications.