79 GHz Fully Integrated Fully Differential Si/SiGe HBT Amplifier for Automotive Radar Applications

In this work, the authors present a fully integrated, fully differential amplifier operating at 79 GHz using a highspeed Si/SiGe hetero-bipolar technology. This amplifier needs a single supply voltage and shows high performance such as high gain, excellent reverse isolation and low power consumption (90 mW at 3 V supply voltage). This result was achieved by using multi-stage cascode topology and a thin-film microstrip line based design. In addition, the frequency of operation can be easily adjusted within a wide range by changing the length of the matching network (by using focused ion beam or ultrasonic manipulator). A simple but efficient layout technique was used to easily measure single-endedly the differential integrated circuit, also at these high frequencies.