Tomographic analysis of reflectometry data II: the phase derivative
  A tomographic technique has been used in the past to decompose complex signals in its components. The technique is based on spectral decomposition and projection on the eigenvectors of a family of unitary operators. Here this technique is also shown to be appropriate to obtain the instantaneous phase derivative of the signal components. The method is illustrated on simulated data and on data obtained from plasma reflectometry experiments in the Tore Supra. 
F. Briolle, R. Lima, R. Vilela Mendes