A 1–42 GHz GaN Distributed Amplifier With Adjustable Gain by Voltage-Controlled Switch

A 1–42 GHz gain-variable distributed amplifier is presented in the letter using a 0.13-
$\mu \text{m}$
gallium nitride (GaN) process. The amplifier can achieve a gain tuning range of about 3 dB over the entire frequency band by voltage-controlled switching. The chip area of the amplifier is about
$1.9\times1.1$
mm
²
. The average output power of the amplifier is greater than 27.5 dBm over the entire bandwidth. A wider gain tuning range can be achieved by adding more voltage-controlled switches.