Pushbroom radiometry and its potential using large space antennas
Abstract
Electromagnetic radiation is emitted by matter which was heated to a temperature above absolute zero. The amount of blackbody radiation in the microwave frequency region of interest (10 to the 8th power f 10 to the 10th power Hz) emitted by matter can be determined from the Rayleigh-Jeans approximation to Planck's Radiation Law. The amount of electromagnetic radiation from matter which is not a blackbody is a function of the emissivity of the material. The emissivity is a factor less than unity and is a function of several parameters including chemical composition, temperature, frequency, surface characteristics, and viewing angle. A radiometer is an instrument which detects and provides a measure of the electromagnetic radiation being emitted by a material or surface area within the radiometer's antenna beamwidth. Microwave radiometers provide the capability for remote measurements from Earth orbits of geophysical parameters. These measurements will require the use of a microwave imaging radiometer using a large aperture deployable antenna with multiple beams in a pushbroom mode to achieve high spatial resolution and large swath width.
- Publication:
-
Large Space Antenna Systems Technology
- Pub Date:
- May 1983
- Bibcode:
- 1983lsas.rept...81H
- Keywords:
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- Earth Observations (From Space);
- Electromagnetic Radiation;
- Large Space Structures;
- Microwave Radiometers;
- Multibeam Antennas;
- Black Body Radiation;
- Brightness Temperature;
- Earth Resources;
- Plancks Constant;
- Rayleigh Equations;
- Remote Sensing;
- Spatial Resolution;
- Launch Vehicles and Space Vehicles