| Galactic Noise and Passive Microwave Remote Sensing from Space at L-Band Contributor(s): Levine, David M. (Author), Abraham, Saji (Author), Nasa Technical Reports Server (Ntrs) (Created by) |
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ISBN: 1287292178 ISBN-13: 9781287292173 Publisher: Bibliogov OUR PRICE: $14.96 Product Type: Paperback Published: August 2013 |
| Additional Information |
| BISAC Categories: - Political Science |
| Physical Information: 0.06" H x 7.44" W x 9.69" (0.15 lbs) 28 pages |
| Descriptions, Reviews, Etc. |
| Publisher Description: The spectral window at L-band (1.4 GHz) is important for passive remote sensing of soil moisture and ocean salinity from space, parameters that are needed to understand the hydrologic cycle and ocean circulation. At this frequency, radiation from extraterrestrial (mostly galactic) sources is strong and, unlike the constant cosmic background, this radiation is spatially variable. This paper presents a modern radiometric map of the celestial sky at L-band and a solution for the problem of determining what portion of the sky is seen by a radiometer in orbit. The data for the radiometric map is derived from recent radio astronomy surveys and is presented as equivalent brightness temperature suitable for remote sensing applications. Examples using orbits and antennas representative of those contemplated for remote sensing of soil moisture and sea surface salinity from space are presented to illustrate the signal levels to be expected. Near the galactic plane, the contribution can exceed several Kelvin. |