In polarimetric remote sensing, one can use the symmetric 2 X 2 backscattering dyadic to obtain information concerning the target. When operating at a single frequency, however, the amount of information is limited and there is an ambiguity in applying simple scattering models to the data. By extending the bandwidth in the sense of a pulse or multiple frequencies (retaining phase) more information concerning the target can be obtained, to which more sophisticated scattering models can be applied. In the form of the temporal backscattering dyadic (operator), temporal isolation via windows can also be used to separate scattering events for separate analysis.
Carl E. Baum,
"Decomposition of the backscattering dyadic", Proc. SPIE 3120, Wideband Interferometric Sensing and Imaging Polarimetry, (23 December 1997); doi: 10.1117/12.300634; https://doi.org/10.1117/12.300634