RFI Monitoring – SMOS blog

Radio-Frequency Interference (RFI) in SMOS context are artificial emissions made within the 1400-1427 MHz band, which is preserved by ITU-R regulations for passive measurements. Due to the large number of interference sources all over the world, RFIs represent a major concern for SMOS and efforts are being made in order to detect, localize, mitigate and monitor their impact on science data. Below we present two tools that allow the assessment of global RFI contamination for a specific period of time:“RFI probability” provides information about all grid points on ground“RFI characterization” provides information about the RFI sources

RFI Probability

The SMOS soil moisture level 2 product has an RFI detector which enables to establish the RFI presence probability (in blue very low probability in red very high). We are also working on other approaches over the Ocean , using other Channels (Stokes 3 and 4 etc… )

RFI Characterization

RFI as seen by SMOS can be characterized according to their position, brightness temperature and persistence. This is done identifying the local maxima in each snapshot using adaptive thresholds on the brightness temperature (BT) and the BT gradients [1].

Explore RFI characterization archive through:

+ 3D navigable maps (Google Earth) (Mac OS X and Windows only)

[1] Soldo, Y., Cabot, F., Khazaal, A., Miernecki, M., Slominska, E., Fieuzal, R., & Kerr, Y. H. (2015). Localization of RFI sources for the SMOS mission: a means for assessing SMOS pointing performances. Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of, 8(2), 617-627.