A 15 element focal plane array for 100 GHz

Abstract

A focal plane imaging array receiver is described which covers the 86-115 GHz frequency range for radio astronomical observations. The 3*5 element array uses cryogenic Schottky diode mixers with integrated HEMT IF amplifiers. A cold quasi-optical filter selects the desired sideband, and terminates the image at 20 K. Polarization interleaving is used to minimize the array size on the sky. LO power is provided by a frequency tripled YIG tuned oscillator. The average receiver noise temperature of the array pixels varies from 250-350 K SSB depending on the frequency. Only three mechanical tuners are used in the system and all functions are under computer control.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>