Detection and mitigation of radiometers radio-frequency interference by using the local outlier factor

Large amounts of radio-frequency interference (RFI) are present in Earth observations at the L-band frequencies of European Space Agency’s Soil Moisture and Ocean Salinity, the National Aeronautics and Space Administration’s Aquarius and Soil Moisture Active and Passive missions. Multiple approaches have been proposed to detect and eliminate the RFI signals in the past few decades, including time, statistical, polarimetric and frequency domain methods. This letter focuses on a new potential RFI detection and mitigation algorithm that is based on the local outlier factor (LOF). Experimental results show that a satisfactory performance can be obtained by an LOF algorithm even in detecting moderate RFI.