5G Updates: Reduced Capabilities in 5G or 5G RedCap NR

5G RedCap NR (Concept by Microsoft CoPilot AI)

RedCap is abbreviation for Reduced Capabilities in 4G or 5G. This tech was conceptualized during Release 17 but it is getting traction in the era of 5G-NR (New Radio). 5G RedCap is also known as 5G NR-Light.

If you can remember Uninor or Telenor India has launched 4G over 1800MHz in India - that was narrow band LTE or NB-LTE. RedCap can be utilized in such scenario. 

"5G RedCap is introduced to bridge the gap between 4G and 5G. The minimum 5G requirement earlier was 100 MHz bandwidth and 4 RX antennas. This was not suited for low-cost and battery-involved LPWA IoT applications. 5G RedCap is defined to power low complexity LTE and NR devices with minimum hardware requirement. It functions in the FR2 frequency range of 5G NR making a whole new band of frequencies available for current 4G devices and initiates the migration from 4G to 5G."

The use cases that motivate the specification work on NR RedCap include wearables (e.g. smart watches, wearable medical devices, AR/VR goggles, etc.), industrial wireless sensors, and video surveillance. 

These use cases have very different requirements than the low-power wide-area (LPWA) use cases currently addressed by the LTE-M and NB-IoT solutions. For example, the data rates need to be higher than for LPWA. Furthermore, there is a constraint on device form factor for certain wearable use cases. The consideration of use-case requirements drives the choices of key physical-layer parameters for RedCap. These choices have a direct impact on the complexity and cost of the device hardware platform. Ericsson foresee that RedCap devices will be positioned as a lower segment than eMBB, but higher than LPWA devices.

Features in 5G RedCap:

• Lower Latency: 5G RedCap offers lower latency. Depending on the use cases, it can be as low as 5 ms. 

• Higher Peak Data Rate: 5G RedCap can provide faster peak data speeds, making it suitable for applications with maximum data throughout.

• Improved Power Consumption: 5G RedCap devices are either static or slow-moving, so reducing network monitoring activities can produce significant battery power savings.

• Bandwidth: RedCap uses a narrow bandwidth spectrum, 20MHz of bandwidth below 6GHz, far less than the typical 100MHz of 5G in eMBB.

• Antenna: 5G NR RedCap has reduced the number of transmitting and receiving antennas, MIMO layers, and the capability requirements of terminal RF transceivers and baseband processing modules.

• Modulation: RedCap defines the modulation mode of 64QAM (quadrature amplitude modification) at the highest level in the standard, but the terminal can flexibly support 256QAM too.

• Duplex: 5G NR RedCap adopts half-duplex FDD/ full-duplex Frequency Division Duplexing. It increases scheduling complexity as RedCap half-duplex devices do not monitor DL messages while communicating in UL.

From Indian prospective RedCap can be the answer to telecom service providers to monetize 5G which is due since commercial launch of 5G. Also it could enhance the private 5G networks which are yet to be seen in Indian telecom sector. But there is a catch, RedCap works only on 5G-SA network, which Airtel don't have. (Update Airtel now have both 5G-NSA and 5G-SA network since July 2024)

In October 2023, Airtel did a successful trial with Ericsson's RedCap solution on its 5G network in collaboration with Qualcomm Technologies, Inc. using its 5G RedCap test module. The testing of RedCap on Airtel's 5G TDD network notes the first implementation and validation of RedCap in India.

Though Jio did not commence any RedCap trial so far, it is kept for future. On its 5G-Advanced page, the telco noted that 'RedCap-enabled devices are expected to boost network efficiency by reducing the capability requirements from the radio network.' Jio might take huge advantage of RedCap as it acquired Mimosa Networks from Airspan via Radisys, the wholly owned subsidiary of Jio Platforms in March 2023. Jio has been a major customer of Mimosa, for rolling out FWA - which is branded as Jio AirFiber. In 2017, Mimosa invented its proprietary Spectrum Reuse Synchronization (SRS) technology for FWA. SRS allows a single access point to efficiently reuse channels rather than wasting spectrum to avoid interference.

In March, 2024 STC Kuwait rolled out world's first RedCap based 5G-FWA services to residential and commercial users using tech from Huawei.