Monolithic power amplifiers covering 70-113 GHz

Abstract

A number of monolithic W-band power amplifiers (PAS) have been developed for local oscillators of the Far Infrared and Submillimeter Telescope (FIRST). These PA chips include three driver and three power amplifiers covering most of the W-band, i.e., the frequency ranges of 72-81, 90-101, and 100-113 GHz. Each driver ampliiier and power amplifier provides at least 20 and 22 dBm (160 mw), respectively in the frequency range it covers. The 100-113 GHz power amplifier has a peak power of greater than 250 mW (25 dBm) at 105 GHz, which is the best output power performance for a monolithic amplifier above 100 GHz to date. These monolithic chips are fabricated using 0.1-pm AlGaAs/InGaAs/GaAs pseudomorphic T-gate power HEMTs on a 2-mil GaAs substrate.

MMICs in the millimeter-wave regime

“…The operating frequencies of SiGe HBT power amplifiers are similar to those of CMOS power amplifiers but with better power performance because of the high current density. On the other hand, millimeter-wave power amplifiers using HEMTs can operate at higher frequencies (up to 113 GHz) with higher output power [73]. There have been reports on the linearization of GaAs pHEMT millimeter-wave power amplifiers to improve the linearity [74].…”

On the stability of millimeter-wave power amplifiers

“…Millimeter-wave power amplifiers are increasingly in demand for higher bandwidth communication, local oscillator sources, automotive radar, and fiber optic communication [ 1,2]. As the need for higher frequency power amplifiers increases, some design issues affecting power amplifier stability become important.…”