% Code_Package Name：A three-component polarimetric decomposition method constrained by MF3C DEMO % Author: Wenxin Xue (wenxin@cug.edu.cn), China University of Geosciences (Wuhan) % Tutor: Qinghua Xie (xieqh@cug.edu.cn), China University of Geosciences (Wuhan) % Date: Sep. 2025

This TCPD-MF-SM-Demo shows the three-component polarimetric decomposition method constrained by MF3C (TCPD-MF) for soil moisture (SM) retrieval.

% Step 1: Utilize SNAP for data preprocessing to generate the T3 matrix and local incidence angle (IA). Load the resulting .mat file (Data_T3_IA.mat) into MATLAB.

% Step 2: Input the T3 matrix and incidence angle into the function 'Cal_surfaceScattering'. % Within this function: % Compute the scattering power values of the MF3C decomposition. % Calculate the proportionality coefficient m to normalize the volume scattering component.

% Step 3: Establish a revised volume scattering coherency matrix based on the methodology described in the paper. Subtract the volume scattering component to isolate the surface scattering contribution.

% Step 4: Feed the ground scattering coherency matrix into the function 'inversion_Tg_Xbragg', which models ground scattering as the superposition of surface scattering and double-bounce scattering. % Iterate over the parameter β (beta) to reconstruct candidate ground scattering matrices. % Compute the Frobenius norm of the residual matrix (observed vs. simulated values). % Identify the optimal parameter set by minimizing the Frobenius norm, thereby completing the three-component decomposition.

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%NOTE: This is just a demo providing a default initialization. Training is not at all optimized. Other initializations, optimization techniques, and training strategies may be of course better suited to achieve improved results in this or other problems. We just did it in the standard way for illustration purposes and dissemination of these models.