Submillimeter-wave heterodyne spectroscopy with a compact solid state radiometer
Abstract
A compact, solid state submillimeter-wave heterodyne radiometer has been developed and was used to measure spectral characteristics of a water vapor jet in a space simulation chamber. Features of the 557 GHz water vapor line profile were observed in significantly greater detail than in previous experiments through an increased sensitivity and improved frequency resolution (600 kHz). The local oscillator of the radiometer consisted of a frequency multiplication chain which was driven by an InP Gunn oscillator at 92.6 GHz, and which contained a frequency tripler and harmonic mixer in cascade. The front end of the receiver had a noise temperature of 4500 K (DSB) at 555 GHz, consumed 3 W and weighed 3 kg. This advance in technology is particularly relevant to submillimeter-wave radiometry from a space-based platform.
- Publication:
-
International Journal of Infrared and Millimeter Waves
- Pub Date:
- August 1985
- DOI:
- 10.1007/BF01011946
- Bibcode:
- 1985IJIMW...6..687T
- Keywords:
-
- Frequency Multipliers;
- Heterodyning;
- Microwave Radiometers;
- Solid State Devices;
- Spectroscopy;
- Submillimeter Waves;
- Absorption Spectra;
- Avalanche Diodes;
- Block Diagrams;
- Gallium Arsenides;
- Gunn Effect;
- Optical Thickness;
- Oscillators;
- Schottky Diodes;
- Spacecraft Instrumentation;
- water vapor spectroscopy;
- submillimeter-wave radiometry;
- heterodyne radiometer;
- submillimeter-wave oscillator;
- frequency multiplier