A cooled Schottky-diode mixer for 75-120 GHz
Abstract
A cryogenic, ultra-low noise mixer has been designed and built at the Five College Radio Astronomy Observatory. New details of this mixer include improved waveguide, backshort, RF-filter and IF-matching and bias circuit designs. The mixer works evenly at frequencies 75-120 GHz. This mixer is used in a cooled receiver (15 K) where LO is coupled by an adjustable ring-filter, and the mixer is followed by a 4.5-5.0 GHz IF system with a temperature equal to 24 K. A cooled receiver noise temperature of 140 K was measured at f(LO) equals 110 GHz when the LO power was only 30 microwatts. This result implies a mixer noise temperature of less than 60 K.
- Publication:
-
10th European Microwave Conference
- Pub Date:
- 1981
- Bibcode:
- 1981eumw.conf..717R
- Keywords:
-
- Cryogenic Cooling;
- Cryogenic Equipment;
- Low Noise;
- Mixing Circuits;
- Network Synthesis;
- Schottky Diodes;
- Systems Engineering;
- Astronomical Observatories;
- Performance Tests;
- Radio Astronomy;
- Room Temperature;
- Waveguides;
- Electronics and Electrical Engineering