RFI characterization for SMAP using L-band direct sampled data obtained during the SMAPVEX12 airborne campaign

NASA´s Soil Moisture Active Passive (SMAP) mission (scheduled for launch in 2014) will have an L-band radiometer to measure brightness temperature values for retrieving soil moisture information. Previous studies have shown that, although the 1400-1427 MHz frequency band is allocated for geophysical remote sensing applications, significant RFI corruption nevertheless occurs. The SMAP radiometer will utilize a digital backend to improve the detection and mitigation of RFI. The digital backend will use a 3.2 kHz sampling frequency to allow sub-milisecond pulse detection and mitigation techniques. In addition, the digital backend will also provide 16 frequency channels (1.5 MHz bandwidth each) so that spectral RFI detection methods can be applied. Finally, the SMAP digital backend will compute the first four moments of observed fields, making computation of the Kurtosis statistic possible as well.