Performance of SMAP radiometer RFI detection algorithms and analysis of residual RFI sources

NASA's Soil Moisture Active and Passive (SMAP) satellite was launched in January 2015 to provide global measurements of soil moisture and freeze/thaw state. Soil moisture products are derived from SMAP radiometer measurements acquired at L Band (1.4 GHz). Even though this is a protected band, unauthorized transmitters emitting either within the band or in adjacent bands cause radio frequency interference (RFI). Because RFI contributions corrupt the radiometer measurements and therefore can lead to biases in retrieved soil moisture, the SMAP radiometer includes special hardware to enable RFI detection and filtering using multiple detection algorithms. This paper investigates the performance of SMAP's RFI detectors, which include pulse, cross-frequency, kurtosis, and polarimetric methods, as a function of the power of the RFI sources. Methods for examining residual RFI remaining after detection and filtering is applied are also discussed.

[1]  Sidharth Misra,et al.  RFI detection and mitigation for microwave radiometry with an agile digital detector , 2006, IEEE Transactions on Geoscience and Remote Sensing.

[2]  Joel T. Johnson,et al.  SMAP L-Band Microwave Radiometer: RFI Mitigation Prelaunch Analysis and First Year On-Orbit Observations , 2016, IEEE Transactions on Geoscience and Remote Sensing.

[3]  Jiancheng Shi,et al.  The Soil Moisture Active Passive (SMAP) Mission , 2010, Proceedings of the IEEE.

[4]  Christopher Ruf,et al.  Radio-Frequency Interference Mitigation for the Soil Moisture Active Passive Microwave Radiometer , 2014, IEEE Transactions on Geoscience and Remote Sensing.