0-40 GHz GaAs MESFET distributed baseband amplifier ICs for high-speed optical transmission

We describe distributed amplifiers built using advanced circuit design techniques to improve gain and noise performance at low frequencies. Using these techniques we have developed an amplifier IC with a 0-36 GHz bandwidth and a noise figure of 4 dB at low frequencies. This frequency range starting from 0 Hz makes it possible to use the IC as a baseband amplifier for SDH optical transmission systems and this noise figure is about 1 dB better than conventional distributed amplifiers. We also present another amplifier IC built using our loss compensation technique to improve high-frequency performance of the amplifier. This IC has a 0-44-GHz bandwidth, which is the widest among all reported GaAs MESFET baseband amplifiers.