Design of a 94 GHz balanced resistive mixer using a 0.1 um GaAs pHEMT technology

This paper presents a passive planar balanced mixer for 94 GHz applications, based on a commercial 0.1 um GaAs pHEMT technology from WIN Semi. Corp. This mixer shows a single-ended output conversion loss between 9 dB and 11 dB pumped with a 10 dBm LO signal at 94 GHz and a RF input 1dB compression point around 0 dBm. In this design, a Lange plus a 90 degrees electrical length microstrip line is adopted in RF signal path to generate a pair of out of phase RF signals. Meanwhile, this balanced structure provides a LO port to RF port isolation above 20 dB in all W-band. Before final measurements, all bare chips have been thinned to 100 um.