Design of an L-Band Microwave Radiometer with Active Mitigation of Interference

For increased sensitivity in L-band radiometry, bandwidths on the order of 100 MHz are desirable. This will likely require active countermeasures to mitigate RFI. In this paper, we describe a new radiometer which coherently samples 100 MHz of spectrum and applies realtime RFI mitigation techniques using FPGAs. A field test of an interim version of this design in a radio astronomy observation corrupted by radar pulses is described. Measurements of the radio frequency environment at L-band from an airborne system are also discussed.