A 30 GHz bandwidth AlGaAs-GaAs HBT direct-coupled feedback amplifier

A DC to 30 GHz broadband amplifier based on the Darlington connected transistors with series and shunt resistive feedback was implemented with self-aligned AlGaAs-GaAs heterojunction bipolar transistor (HBT) technology. The measured performance shows 7.8 dB of gain with -3-dB roll-off bandwidth of 30 GHz. Measured at 1 GHz, the noise figure was 5.7 dB, 1-dB compression power was 11 dBm, and the third-order intermodulation product intercept point (IP3) was 23.9 dBm.<
>