A new staring 94-GHz focal plane array

Abstract

A new staring 94 GHz focal plane array (4x8 pixels) multi-chip module (MCM) using a quasi-optically pumped MMIC gate mixer is presented. The new MCM with integrated microstrip antennas, matching and bias networks are manufactured using a modified MCM-D process based on 3x15 m BCB. The active gate mixer MMIC was manufactured by OMMIC (D01PH process) and uses a 2x25 um gate width. The 30 cm dielectric lens antenna has a F/D number of approximately unity. To minimize the spillover loss, the beamwidth of the feed antennas (microstrip antennas) was matched to the opening angle of the lens by using 2x2 subarrays for each pixel. Preliminary measurement results show a feed antenna gain of approximately 10 dBi and a conversion loss close to zero at 94 GHz, and an optimal pumping power of -2 dBm at 92.4 GHz.