RFI Problems and Solutions in Spaceborne Microwave Radiometers
نویسنده
چکیده
The problem of RFI in spaceborne microwave radiometer data has been known since 1978 when it was first observed at 6.6 GHz with SMMR on SeaSat. Over the last several years, however, it has started to seriously impact remote sensing science products and is expected to continue to do so. This is primarily because the frequency requirements of remote sensing have begun to overlap active radio service allocations. For example, soil moisture is being sensed in the C-band, for which there is no passive service allocation. Thus, RFI detection and mitigation strategies are needed to ensure a radiometer will not be damaged by extreme RFI (survivability), can make measurements during RFI events (operability), and lastly will enable the removal of detectable RFI (excisability). Application to NASA's Aquarius radiometer and NASA's future SMAP radiometer, as well as potential application to the NPOESS MIS radiometer, will be discussed.
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