mmWave CMOS Power Amplifiers for 5G Cellular Communication

This article covers the basics of millimeter-wave PA design in CMOS technology for integrated phased arrays, targeting the upcoming 5G new radio (NR) cellular communication standard. Key PA figures of merit, as well as application of beam-forming phased arrays to combine power over-the-air, are briefly reviewed. Then, starting from practical handset form factor constraints and system-level drivers, CMOS-specific technological and design-related challenges are conceptually illustrated using a simple single-transistor PA. A survey of the state-ofthe- art is presented to give examples of the challenges and illustrate the PA techniques used to tackle them in linear 28-GHz CMOS PAs for 5G NR.