A single-chip 77 GHz heterodyne receiver MMIC in 100 nm AlGaN/GaN HEMT technology

The paper presents the design, implementation and measured performance of a 77 GHz heterodyne receiver MMIC realized in a new AlGaN/GaN on s.i. SiC HEMT technology with 100 nm gate length and maximum cutoff frequencies f_T and f_max of 80 and >;200 GHz, respectively. The compact single-chip receiver combines a four-stage low noise amplifier with a resistive down-conversion mixer and a frequency doubler stage for LO generation. At 77 GHz RF frequency, it achieves a conversion gain of 11 dB when driven with 10 dBm of LO power at 38.5 GHz. The saturated IF output power, without any post-amplification, is more than 1 dBm. The receiver is dedicated to radar systems with high linearity requirements and high robustness from strong interferers or reflected signals.