To investigate the effect of forest spatial structure on SAR interferometry (InSAR) data requires an electromagnetic scattering model capable of expressing radar observation in terms of parameters describing forest spatial structure. In this paper, we propose an electromagnetic scattering model for mixed-species forest which includes the coherent effect of forest structure and preserves phase information of radar backscattering signal. Interferometric SAR images of three-dimensional (3-D) scenes are simulated based on this model and the heights of scattering phase centers are estimated from the simulated InSAR data. The results show that the model is suitable for simulating interferometric SAR response to forest canopies and for investigating the forest spatial structure.
We also compare the backscattering coefficients predicted by the proposed electromagnetic scattering model with the JERS-1 L-band SAR and ENVISAT ASAR C-band data acquired at forest stands of Changqing test site in Daxinganling, Northern China. Good agreements are obtained between the model results and measurement data.
"Analysis of InSAR
Sensitivity to Forest Structure Based on Radar Scattering Model," Progress In Electromagnetics Research,
Vol. 84, 149-171, 2008. doi:10.2528/PIER08071802
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