RF CMOS

RF CMOS is a metal–oxide–semiconductor (MOS) integrated circuit technology that combines radio-frequency, analog, and digital functions on a single mixed-signal CMOS chip. It is a core component of modern wireless telecommunications, appearing in cellular networks, Bluetooth, Wi-Fi, GPS receivers, broadcasting, vehicular communication systems, and the radio transceivers found in every contemporary mobile phone and wireless networking device.

The technology was pioneered by Pakistani engineer Asad Ali Abidi at UCLA from the late 1980s into the early 1990s. Abidi’s earlier work at Bell Labs on sub-micron MOSFETs and NMOS circuits for high-speed communication was met with skepticism from proponents of GaAs and bipolar transistors, then the dominant high-speed technologies. After moving to UCLA in 1985, he shifted the design of RF circuits away from discrete bipolar transistors toward CMOS integrated circuits. In 1993, together with UCLA colleagues J. Chang and Michael Gaitan, he demonstrated the first RF CMOS amplifier. Two years later, he used CMOS switched-capacitor technology to build the first direct-conversion transceivers for digital communications. By the late 1990s, RF CMOS had been widely adopted in wireless networking as mobile phones entered widespread use, replacing discrete bipolar transistors in radio transceivers.

The development of low-cost, very-large-scale integration RF CMOS enabled digital signal processing in wireless communications, leading to sophisticated, low-power, portable end-user terminals. This drove the rapid growth of the telecommunications industry and helped bring about the wireless revolution, making “anytime, anywhere” communication possible. In the early 2000s, RF CMOS chips with deep sub-micron MOSFETs capable of operating above 100 GHz were demonstrated. By 2008, all wireless networking devices and modern mobile phones mass-produced their radio transceivers as RF CMOS devices.

Today, baseband processors and radio transceivers in all modern wireless devices are mass-produced using RF CMOS. The technology is used for satellite technology (including GPS), Bluetooth, Wi-Fi, near-field communication, mobile networks (such as 3G and 4G), terrestrial broadcast, and automotive radar. Commercial examples include Intel’s DECT cordless phone, 802.11 chips from Atheros and others, and products for Bluetooth and Wireless LAN.