Forest Height Inversion Based on Time–Frequency RVoG Model Using Single-Baseline L-Band Sublook-InSAR Data

The interferometric synthetic aperture radar (InSAR) technique based on time–frequency (TF) analysis has great potential for mapping the forest canopy height model (CHM) at regional and global scales, as it benefits from additional InSAR observations provided by sublook decomposition. Meanwhile, due to wider swath higher spatial resolution of single-polarization data, a observation efficiency in comparison with PolInSAR. However, accuracy CHM inversion obtained TF-InSAR method is attenuated its inaccurate coherent scattering modeling uncertain parameter calculation. Hence, new approach estimation single-baseline data decomposition proposed this study. With derivation matrix observations, random volume over ground (TF-RVoG) describe relationship between coherence biophysical parameters. Then, modified three-stage TF-RVoG used retrieval. Finally, two-dimensional (2-D) ambiguous error pure caused residual temporal decorrelation alleviated complex unit circle. performance was tested airborne L-band E-SAR Krycklan test site Northern Sweden. Results show that provides root-mean-square (RMSE) 5.61 m using 14.3% improvement PolInSAR respect classical result. An RMSE = 2.54 when heterogeneity considered method, demonstrating noticeable 32.8% compared results existing which introduces fixed factor.