RF CMOS come of age

Radio-frequency integrated circuits (RFICs) in complementary metal-oxide semiconductors (CMOS) are developing a strong presence in the commercial world. They are dominant for applications such as wireless LAN and Bluetooth and are making inroads into areas such as global system for mobile communications (GSM) cellular transceivers and global positioning system (GPS) receivers. This article offers a brief retrospective on how RF circuits and systems in CMOS have evolved to their current state of the art, followed by perspective of what the future might hold for RF systems on a chip (SOC) in CMOS. It seems appropriate today, roughly ten years after the first publications reporting RF circuits in CMOS, to document the key developments and first reports of the circuit techniques and architectural innovations that are now in widespread use for the development of a new generation of RFICs.