Evolution of the Radio Frequency Interference Environment Faced by Earth Observing Microwave Radiometers in C and X Bands Over Europe

Significant information for understanding the Earth's environment such as sea surface temperature, rain rates, and ocean wind speeds, is retrieved using C and X band spaceborne radiometer measurements. However, radio spectrum is a limited resource, and as new communication and military technologies emerge, more and more human-made signals occupy these frequency bands allocated for passive remote sensing of Earth. This paper demonstrates the expansion of the interference problem due to such signals from 2002 to present using 6.9GHz and 10.65GHz AMSR-E and AMSR2 measurements over Europe.