A W-band heterodyne receiver module prototype for focal plane arrays

A compact W-band heterodyne receiver module populated with MMIC LNAs designed and fabricated using a 35 nm InP HEMT process, and an IQ mixer designed and fabricated using the UMS Schottky diode process is developed as the prototype for Argus, a 16-pixel focal plane array to be deployed on the 100-meter Robert C. Byrd Green Bank Telescope in West Virginia to study star formation. The module has a WR-10 waveguide input. GPPO connectors are used for the LO input and the I and Q IF outputs. The module is tested at both ambient (300 K) and cryogenic (26 K) temperatures. A minimum receiver noise temperature of 27 K was achieved, with less than 45 K noise and more than 20 dB gain in the 85 GHz to 116 GHz band. The band-averaged noise temperature is 34 K and 249 K for a physical temperature of 26 K and 300 K, respectively. The IQ amplitude and phase balance shows image rejection better than 15 dB over 90 percent of the band with constant current operation of both mixers. Image rejection better than 25 dB is measured when optimized currents are used to drive the I and Q mixers.