Radio frequency interference in ALOS-2 PALSAR-2 interferogram

In this paper, a Radio frequency interference (RFI) in ALOS-2 PALSAR-2 interferogram is discussed. L-band synthetic aperture radar (SAR) systems share the band with global navigation satellite systems (GNSS), communication systems and aircraft surveillance radars, resulting in severe effect of RFIs. In general, all RFSs do not have temporal coherency. That is, if one makes a multi-temporal interferogram from SAR images, RFI signals in the images will appear as noise in the interferogram. However, some RFIs in PALSAR-2 have high interferometric coherence. That is, the phase component of some region in the interferogram does not represent the signals from the scatters on the ground but RFIs, though there is high interferometric coherence. Here, some results in Tokyo international airport in Tokyo bay are presented and discussed.