MaxLinear, Inc. announced Sierra, a fully integrated System on Chip (SoC) for 4G/5G Open RAN (Radio Access Network) radio units (RU). This complete silicon and software solution provides RU designers with a flexible system building block to deliver Macro, Massive MIMO, and Small Cell radios for Open RAN applications with high performance, low power consumption, and short time-to-market. The company began work last year in a collaboration with Meta Connectivity to design the single-chip solution.

Sierra integrates the following sub-systems into a single chip to provide a compact and complete software-programmable radio signal processing engine for Open RAN RUs: RF Transceiver supporting up to 8 transmitters, 8 receivers, and 2 feedback receivers; Digital Front End (DFE), powered by MaxLIN™ the industry's leading digital pre-distortion (DPD) and crest factor reduction (CFR) solution, and supporting digital up-conversion (DUC) and digital down-conversion (DDC) of component carriers; Low PHY Baseband Processor supporting 5G, 4G, and NB-IoT air interfaces; Fronthaul Interface compliant with O-RAN Alliance Split 7.2x. More about Sierra: At the heart of Sierra is MaxLIN™, the industry's leading DPD solution for wideband power amplifier linearization. Its linearization performance exceeds the 3rd Generation Partnership Project (3GPP) and Federal Communications Commission (FCC) unwanted emissions requirements with margin while delivering high PA efficiencies of >50%.

The MaxLIN platform is software configurable to optimally support different PA architectures, technologies, and power levels for all potential RU applications from macro to pico cells. Its advanced machine learning algorithms feature variable delay memory banks, flexible logic and company enhancements to correct for both long term and short-term nonlinear dynamics including GaN charge trapping and thermal transients.