@article {829,
	title = {Inclusion of a simple multiple scattering model into a microwave canopy backscatter model},
	journal = {Remote Sensing of Environment},
	volume = {63},
	year = {1998},
	note = {JOURNAL ARTICLE; RESEARCH ARTICLE},
	month = {1998},
	pages = {101-111},
	abstract = {A simple multiple scattering model has been incorporated into a microwave canopy backscatter model for forest stands with continuous or discontinuous tree canopies. The multiple scattering model was empirically derived using available calculated multiple scattering values and Monte Carlo simulation. All orders of scattering within canopies beyond single scattering were assumed to be isotropic. Multiple scattering was divided evenly among HH, HV, VH, and VV polarizations. The corresponding single scattering term was polarization-sensitive. The effect of the multiple scattering term on modeled canopy backscatter was less at long wavelengths than at short wavelengths. At a given wavelength, the multiple scattering term affected copolarized scattering less than cross-polarized scattering. These predictions were consistent with calibrated SAR observations and with our understanding of microwave scattering in forested environment. Including multiple scattering effects improved the agreement between modeled and measured canopy backscatter particularly for cross-polarized backscatter at short wavelengths.},
	keywords = {(Aerospace and Underwater Biological Effects--General, (Biophysics--Biocybernetics (1972- )), (Ecology, (Mathematical Biology and Statistical Methods), (Radiation--Radiation and Isotope Techniques), Environmental Biology--Plant), Forest Stand, Methods), Microwave Canopy Backscatter Model, Models and Simulations, remote sensing, Research Article, Simple Multiple Scattering Model},
	author = {Wang, Y. and Paris, J. F. and Davis, F. W.}
}
@article {826,
	title = {Sensitivity of modeled C- and L-band radar backscatter to ground surface parameters in Loblolly pine forest},
	journal = {Remote Sensing of Environment},
	volume = {66},
	year = {1998},
	month = {1998},
	pages = {331-342},
	keywords = {Duke Forest},
	author = {Wang, Y. and Day, J. L. and Davis, F. W.}
}
@article {578,
	title = {Decomposition of polarimetric Synthetic Aperture Radar backscatter from upland and flooded forests},
	journal = {International Journal of Remote Sensing},
	volume = {18},
	number = {6},
	year = {1997},
	note = {English Article Current Contents/Physical, Chemical \& Earth Sciences. Reprint available from: Wang Y E CAROLINA UNIV DEPT GEOG GREENVILLE, NC 27858 USA UNIV CALIF SANTA BARBARA INST COMPUTAT EARTH SYST SCI SANTA BARBARA, CA 93106 USA 0010},
	pages = {1319-1332},
	abstract = {The goal of this research was to decompose polarimetric Synthetic Aperture Radar (SAR) imagery of upland and flooded forests into three backscatter types: single reflection, double reflection, and cross-polarized backscatter. We used a decomposition method that exploits the covariance matrix of backscatter terms. First we applied this method to SAR imagery of dihedral and trihedral corner reflectors positioned on a smooth, dry lake bed, and verified that it accurately isolated the different backscatter types. We then applied the method to decompose multi-frequency Jet Propulsion Laboratory (JPL) airborne SAR (AIRSAR) backscatter from upland and flooded forests to explain scattering components in SAR imagery from forested surfaces. For upland ponderosa pine forest in California, as SAR wavelength increased from C-band to P-band, scattering with an odd number of reflections decreased and scattering with an even number of reflections increased. There was no obvious trend with wavelength for cross-polarized scattering. For a bald cypress-tupelo floodplain forest in Georgia, scattering with an odd number of reflections dominated at C-band. Scattering power with an even number of reflections from the hooded forest was strong at L-band and strongest at P-band. Cross-polarized scattering may not be a major component of total backscatter at all three wavelengths. Various forest structural classes and land cover types were readily distinguishable in the imagery derived by the decomposition method. More importantly, the decomposition method provided a means of unraveling complex interactions between radar signals and vegetated surfaces in terms of scattering mechanisms from targets. The decomposed scattering components were additions to the traditional HH and VV backscatter. One cautionary note: the method was not well suited to targets with low backscatter and a low signal-to-noise ratio. [References: 8] 8},
	keywords = {DEPT GEOG, Earth sciences. Reprint available from: Wang Y. E CAROLINA UNIV, GREENVILLE},
	author = {Wang, Y. and Davis, F. W.}
}
@article {825,
	title = {The effects of changes in forest biomass on radar backscatter from tree canopies},
	journal = {International Journal of Remote Sensing},
	volume = {16},
	year = {1995},
	note = {JOURNAL ARTICLE; RESEARCH ARTICLE},
	month = {1995},
	pages = {503-513},
	keywords = {(Aerospace and Underwater Biological Effects--General, (Biophysics--Biocybernetics (1972- )), (Ecology, (Mathematical Biology and Statistical Methods), (Plant Physiology, Biochemistry and Biophysics--Growth, Differentiation), Coniferopsida, Environmental Biology--Plant), Gymnosperms, Mathematical Model, Methods), North Carolina, Pine, Plants, Research Article, Spermatophyta, Spermatophytes, Synthetic Aperture Radar, Usa, Vascular plants},
	author = {Wang, Y. and Davis, F. W. and Melack, J. M. and Kasischke, E. S. and Christensen, N. L., Jr.}
}
@article {828,
	title = {The effects of changes in loblolly pine biomass and soil moisture on ERS-1 SAR backscatter},
	journal = {Remote Sensing of Environment},
	volume = {49},
	year = {1994},
	note = {JOURNAL ARTICLE; RESEARCH ARTICLE},
	month = {1994},
	pages = {25-31},
	keywords = {(Aerospace and Underwater Biological Effects--General, (Biochemistry--Physiological Water Studies (1970- )), (Biophysics--Biocybernetics (1972- )), (Ecology, (Forestry and Forest Products), (Mathematical Biology and Statistical Methods), (Plant Physiology, Biochemistry and Biophysics--Growth, Differentiation), (Plant Physiology, Biochemistry and Biophysics--Water Relations), (Soil Science--Fertility and Applied Studies (1970- )), (Soil Science--Physics and Chemistry (1970- )), Coniferopsida, Environmental Biology--Plant), European Remote Sensing Satellite Synthetic Aperture Radar, Gymnosperms, Mathematical Model, Methods), North Carolina, Plants, Research Article, Spermatophytes, Usa, Vascular plants},
	author = {Wang, Y. and Kasischke, E. S. and Melack, J. M. and Davis, F. W. and Christensen, N. L., Jr.}
}
@article {827,
	title = {Modeling L-Band Radar Backscatter of Alaskan Boreal Forest},
	journal = {IEEE Transactions on Geoscience \& Remote Sensing},
	volume = {31},
	year = {1993},
	note = {English Article Current Contents/Engineering, Technology \& Applied Sciences. Reprint available from: Wang Y UNIV CALIF SANTA BARBARA CTR REMOTE SENSING \& ENVIRONM OPT SANTA BARBARA, CA 93106 USA UNIV CALIF SANTA BARBARA DEPT GEOG SANTA BARBARA, CA 93106 USA UNIV CALIF SANTA BARBARA DEPT BIOL SCI SANTA BARBARA, CA 93106 USA 0003},
	month = {1993},
	pages = {1146-1154},
	abstract = {Synthetic aperture radar (SAR) data were acquired over Bonanza Creek Experimental Forest (Alaska) in March 1988 under thawed and frozen conditions. For five stands analyzed, L-band backscatter at 42-degrees-45-degrees incidence angle was 2.7-6.9 dB smaller under frozen than under thawed conditions for white spruce and balsam poplar, with the largest difference at HV and the smallest at HH polarization. The differences were smaller for a stand of small black spruce. The VV-HH phase differences observed by SAR were almost-equal-to 0-degrees for all the stands. Ground data were used to parameterize the Santa Barbara canopy backscatter model. For the white spruce and balsam poplar stands under thawed conditions, simulations agreed with the SAR data within the calibration uncertainty. The model underestimated the HH, HV, and VV backscatter for all five stands under frozen conditions, and for the black spruce stand under thawed conditions. The modeled VV-HH phase differences were close to 0-degrees for all the stands except the black spruce stand. The discrepancies in model predictions of backscatter and phase difference were attributed to inadequate surface backscatter modeling. Model results supported the hypothesis that the weaker backscatter from frozen, as compared with thawed stands, was because of the smaller dielectric constant of the frozen trees. [References: 15] 15},
	keywords = {Electrical \& electronic., Reprint available from: Wang Y. UNIV CALIF SANTA BARBARA, CTR REMOTE, SENSING \& ENVIRONM OPT, SANTA BARBARA, CA 93106, USA., Vegetation. Layer.},
	author = {Wang, Y. and Day, J. L. and Davis, F. W. and Melack, J. M.}
}
@article {824,
	title = {Simulated and Observed Backscatter at P-, L-, and C-Bands from Ponderosa Pine Stands},
	journal = {IEEE Transactions on Geoscience \& Remote Sensing},
	volume = {31},
	year = {1993},
	note = {English Article Current Contents/Engineering, Technology \& Applied Sciences. Reprint available from: Wang Y UNIV CALIF SANTA BARBARA CTR REMOTE SENSING \& ENVIRONM OPT SANTA BARBARA, CA 93106 USA 0015},
	month = {1993},
	pages = {871-879},
	abstract = {We compared the output of the Santa Barbara microwave canopy backscatter model to polarimetric synthetic aperture radar (SAR) data for three ponderosa pine stands (ST-2, ST-11, and SP-2) with discontinuous tree canopies near Mt. Shasta, California, at P-band (0.68-m wavelength), L-band (0.235-m wavelength), and C-band (0.056-m wavelength). Given the SAR data calibration uncertainty, the model made good predictions of the P-HH, P-VV, L-HH, C-HH, and C-HV backscatter for the three stands, and the P-HV and L-HV backscatter for ST-2 and SP-2. The model underestimated C-VV for the three stands, and P-HV, L-HV, and L-VV backscatter for ST-11. The observed and modeled VV-HH phase differences were similar or equal to 0 degrees for the three stands at C-band and L-band, and for SP-2 at P-band. At P-band, the observed and modeled VV-HH phase differences were at least -80 degrees for ST-2 and ST-11, which indicates that double-bounce scattering contributes to the total backscatter for the two stands. [References: 10] 10},
	keywords = {Electrical \& electronic., Radar. Scattering. Model., Reprint available from: Wang Y. UNIV CALIF SANTA BARBARA, CTR REMOTE, SENSING \& ENVIRONM OPT, SANTA BARBARA, CA 93106, USA.},
	author = {Wang, Y. and Davis, F. W. and Melack, J. M.}
}
