HIGH-GAIN FREQUENCY-TUNABLE LOW-NOISE AMPLIFIERS FOR 38-42.5-GHZ BANDAPPLICATIONS

High-performance tunable low-noise amplifiers for 38-42,5-GHz applicat ions are presented based on a fully stabilized GaAs pseudomorphic high electron mobility transistor (PHEMT) 0.2-mu m technology. A single 1. 5 x 3 mm(2) chip, incorporating six amplifying stages, shows a measure d gain of 36-42 dB depending on the center frequency. Both maximum gai n frequency and input impedance of the amplifier are accurately tunabl e on the chip. This means that the amplifier provides a narrow-band fi ltering function and can be matched to a fast p-i-n photodiode as well as to a 50-Omega load, This is the first time such performances are r eported for single chip narrow-band tunable amplifiers using a GaAs PH EMT technology.