5G presents a challenge for batteries in connected devices. Ookla has estimated that, based on its data, smartphone users connected to 5G networks drain their batteries between 6-11% faster than users on LTE networks—although the newer the chipset inside the device, the better the battery efficienct.
The 5G battery challenge becomes magnified for IoT devices, which often have smaller batteries and/or are designed for use cases where a long battery life is required. 5G Reduced Capability (RedCap), also known as NR-Light, is a Rel. 17 feature set that is meant to open up an expanded device ecosystem where lower power consumption, device simplicity and lower cost can be achieved in 5G.
A white paper from semiconductor and module maker Qorvo lays out how RedCap will enable lower power consumption in 5G devices, as well as reduce the complexity and cost. Most of these revolve around RedCap’s simplified transmission/reception capabilities, compared to MIMO implementations in most 5G scenarios.
Here are some of the ways that RedCap can reduce power consumption:
–Fewer antennas and signal receive chains. RedCap is designed to support one transmit and just one or two receive antennas.
–Narrower bandwidth support. RedCap devices only have to support a maximum bandwidth of 20 megahertz, rather than the 100-megahertz channels required in 5G smartphones. Qorvo notes that this will both reduce power consumption and extend device battery life.
–Not using carrier aggregation. RedCap isn’t required to support CA; it only needs to support one frequency band at a time. This reduces both complexity and power demands.
–Support for fewer frequency bands. 5G smartphones, especially premium handsets, have to support dozens of frequency bands. While RedCap devices such as premium smartwatches may still support both regional and international bands, Qorvo points out that “simpler IoT devices may need just a few bands”—particularly if they’re meant for use in a single geography.
5G RedCap has been standardized with spectrum support in both Frequency Range 1 (sub-6 GHz) and FR2 (millimeter-wave) support, but as with the first wave of 5G, most focus thus far in terms of testing being focused on FR1.
–Operating as a 5G Standalone technology with limited legacy support. RedCap is a 5G Standalone technology, and isn’t required to support 2G and 3G. This, Quorvo points out, means that RedCap devices don’t need 2G/3G power amplifiers, which can consumer a “considerable amount” of power. RedCap devices also are not required by specification to support 5G Non-Standalone mode and dual 4G/5G ENDC connectivity—although early chipsets, such as Qualcomm’s Snapdragon X35 5G modem-RF system, do have the ability for multi-mode operation in 5G SA and as an LTE Cat-4 device, according to device spec sheets.
Looking for more insights on 5G RedCap as a technology, potential use cases and its strategic role in the 5G ecosystem? Check out the editorial webinar available on-demand, featuring Counterpoint Research, module maker Fibocom and Viavi Solutions—and keep an eye out for our upcoming special report!
