A 5-10 GHz octave-band AlGaAs/GaAs HBT down-converter MMIC

This work describes an X-band HBT down-converter MMIC which integrates a double double-balanced Schottky mixer and 5 stages of HBT amplification to achieve >30 dB conversion gain and an IP3 as high as 15 dBm with an RF bandwidth from 5-10 GHz. A novel HBT amplifier gain cell employing active feedback which provides wide bandwidth and high performance in a compact area is used for the RF, LO, and IF amplifier stages. The MMIC is realized in a 3.6/spl times/3.4 mm/sup 2/ area, consumes 530 mW, and is self-biased through a 6 V supply. This MMIC represents the highest complexity X-band down-converter MMIC demonstration based on GaAs HBT and Schottky technology.