On the Performance of Multibaseline SAR Interferometry for Vertical Structure Estimation by means of Polarization Coherence Tomopgraphy

Kurzfassung

In this presentation a new radar-imaging technique, called polarization coherence tomography, PCT, to estimate forest vertical profile is discussed. For PCT is required a priori knowledge of the height and the surface topography, which can be obtained from Pol-InSAR inversion. By using, as reference function, terrestrial light detection and ranging (TLiDAR) data, the performance analysis, for the reconstruction of vertical profile, of multibaseline SAR interferometry by means of PCT is provided. In this technique, the evaluation of the coefficients in order to estimate the structure function is related to an inversion matrix problem. The complexity of this operation can be overcome using the singular value decomposition (SVD) that allow a simple measure of the condition number. How changes the accuracy of the reconstructed profile in presence of several distortions, as the stochastic nature of phase and amplitude volume coherence, is described. Thus decorrelation sources can lead inaccurate Pol-InSAR estimation of forest height and/or ground phase. In this work we discuss the relation between the conditioning and the vertical wavenumber with the result provided from PCT model in presence of decorrelation factor, fluctuations due to a random modeling of phase and amplitude coherence and inaccurate result from Pol-InSAR inversion. A possible upper bound of coefficients error in order to have a reasonable retrieval profile is given. In conclusion we show the effect on the vertical function of several errors arrangements.