As numerical weather prediction systems move towards an integrated Earth system approach, the exploitation of lower frequency channels (10 GHz and below) is becoming increasingly important. One of the challenges of using such channels is contamination from Radio Frequency Interference (RFI). This paper demonstrates two methods for the mitigation of such spurious signals focusing on the screening of RFI from geostationary broadcast satellites for the 10.65 GHz channel of AMSR2 and the use of the differences between the background departures from the NWP system to identify RFI in the 6.9 GHz channel of AMSR2.