Dataset Information

SMAP L-Band Microwave Radiometer: Instrument Design and First Year on Orbit.

ABSTRACT: The Soil Moisture Active-Passive (SMAP) L-band microwave radiometer is a conical scanning instrument designed to measure soil moisture with 4% volumetric accuracy at 40-km spatial resolution. SMAP is NASA's first Earth Systematic Mission developed in response to its first Earth science decadal survey. Here, the design is reviewed and the results of its first year on orbit are presented. Unique features of the radiometer include a large 6-m rotating reflector, fully polarimetric radiometer receiver with internal calibration, and radio-frequency interference detection and filtering hardware. The radiometer electronics are thermally controlled to achieve good radiometric stability. Analyses of on-orbit results indicate that the electrical and thermal characteristics of the electronics and internal calibration sources are very stable and promote excellent gain stability. Radiometer NEDT < 1 K for 17-ms samples. The gain spectrum exhibits low noise at frequencies >1 MHz and 1/f noise rising at longer time scales fully captured by the internal calibration scheme. Results from sky observations and global swath imagery of all four Stokes antenna temperatures indicate that the instrument is operating as expected.

SUBMITTER: Piepmeier JR

PROVIDER: S-EPMC7357195 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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SMAP L-Band Microwave Radiometer: Instrument Design and First Year on Orbit.

Piepmeier Jeffrey R JR Focardi Paolo P Horgan Kevin A KA Knuble Joseph J Ehsan Negar N Lucey Jared J Brambora Clifford C Brown Paula R PR Hoffman Pamela J PJ French Richard T RT Mikhaylov Rebecca L RL Kwack Eug-Yun EY Slimko Eric M EM Dawson Douglas E DE Hudson Derek D Peng Jinzheng J Mohammed Priscilla N PN De Amici Giovanni G Freedman Adam P AP Medeiros James J Sacks Fred F Estep Robert R Spencer Michael W MW Chen Curtis W CW Wheeler Kevin B KB Edelstein Wendy N WN O'Neill Peggy E PE Njoku Eni G EG

IEEE transactions on geoscience and remote sensing : a publication of the IEEE Geoscience and Remote Sensing Society 20170105 4

The Soil Moisture Active-Passive (SMAP) L-band microwave radiometer is a conical scanning instrument designed to measure soil moisture with 4% volumetric accuracy at 40-km spatial resolution. SMAP is NASA's first Earth Systematic Mission developed in response to its first Earth science decadal survey. Here, the design is reviewed and the results of its first year on orbit are presented. Unique features of the radiometer include a large 6-m rotating reflector, fully polarimetric radiometer receiv ...[more]

PMID: 32661449

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Dataset Information

SMAP L-Band Microwave Radiometer: Instrument Design and First Year on Orbit.

Publications

SMAP L-Band Microwave Radiometer: Instrument Design and First Year on Orbit.

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