Passive Remote Sensing of Thin and Thick Components of Vegetation
Keywords:
Electromagnetic (EM), Emissivity, Mathematical Modelling, Remote Sensing, VegetationAbstract
Electromagnetic (EM) waves can be used for constructing the EM model and analyzing the influence of various parameters. The outcome of the analysis can be useful as input to many remote sensing forecasting models. The present study is investigating the emissivity of thin and thick components of vegetation. The investigated terrain, which consists of leaves and branches is considered thin and thick bodies. The mathematical equations are constructed for, absorption cross-sections and emissivity. Then, by using this equation and already driven relations between relevant electromagnetic parameters of thin and thick are compared. Further, the dependency between the aforementioned parameters in emissivity modeling is examined. A comparison of our results with the literature has a good agreement.
References
We found the relations between emissivity and backscattering coefficients of discrete and continuous models.
As seen from the equation, the backscattering coefficients in discrete model and continuous model are related in a multiplicative manner.
The backscattering coefficient can be obtained using eq.19.
Emissivity and absorption cross section have been obtained for thin and thick scatters. Absorption cross section equations have been simulated and calculated to make a comparison with the results from the literature.
In horizontal polarization, the emissivity value is greater at low frequencies. In vertical polarization, higher frequencies give in greater emissivity value, therefore depending on frequency range, horizontal and vertical polarizations could be used in the model. In the thick cylinder model constituted for branches and trunks, simulation parameters are similar. Emissivity curves for both polarizations are decreasing with an increase in frequency. Wider incidence angle causes emissivity to increase.
ACKNOWLEDGMENTS
The authors thank Z. Surmeli and A. Sen for their help.
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