Parameter Estimation Method Of Polarimetric SAR Interferometry SAR Vegetation

Polarimetric interferometric SAR integrates all advantages of interferometry SAR and polarization SAR, which reflects the physical characteristics and spatial distribution properties of targets, so it greatly expands the SAR applications in the field of microwave remote sensing. Through multi-polarimetric SAR data and the correlation matrix eigen-decomposition technique, polarization interference technique can significantly improve the accuracy of the surface parameters inversion, so it provides the possibility for the extraction of high-precision digital elevation information. By retrieving the vegetation parameters, Polarimetric interferometric SAR is of great significance to the forest resource management and environmental monitoring.This paper mainly studies polarimetric interferometric SAR inversion algorithms of ground vegetation height, while detailed discusses polarization coherence tomography (PCT) algorithm. The mainly work and innovation of this paper are as follows:(1) Analysis the characteristics of the scattering mechanism for different polarimetry and their sensitivities for vegetation regional; Research the optimal polarization interference coherence coefficient algorithm, and the real data demonstrates the algorithm can obtain the separation of scattering mechanisms on surface target.(2) Research polarimetric interferometric SAR scattering phase center estimation. First of all, introduce polarimetric interferometric SAR coherent scattering model and analysis different parameters on the impact of coherence; Then study the scattering phase estimation based on ESPRIT algorithm, which can obtain accurate phase estimation of vegetation layer and ground surface; Finally, research the interferometric phase compensation method using optimal volume coherent coefficient, which succeeds reducing interferometric phase error which is brought by the vegetation layer attenuation.(3) Propose three vegetation parameter inversion algorithms of polarimetric interferometric SAR. First, analysis the traditional three-stage method and propose an improved algorithm based on volume coherence coefficient for vegetation height inversion, which can improve the accuracy of vegetation height estimation by getting the accurate estimate of volume coherence coefficient. The simulated data and real data are used to validate the proposed method; Then propose an improved vegetation height inversion algorithm of dual-baseline polarimetric interferometric SAR, which demonstrate the advantages of dual-baseline algorithm with comparison; Finally, a joint vegetation height inversion method is proposed using dual-frequency, and the simulated experiment indicates that this algorithm can improve retrieval accuracy and have good robustness.(4) Study the polarization coherence tomography algorithm. Clarify the principles of polarization coherence tomography algorithm, and introduce the processes and steps of single-baseline and double-baseline polarization coherence tomography algorithm. Finally, the simulation experiment demonstrates that the algorithm is able to obtain the vertical structure function of vegetation, and obviously reflect the surface scattering characteristics.