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Abstract-Spatial fluctuations in microwave backscatter may be an important piece of information in discriminating tree stands. However, the presence of speckle in synthetic aperture radar (SAR) image data is a barrier to the exploitation of image texture. We explored a new methodology that combines a recent adaptive speckle reduction algorithm by Lopes et al.[12] with a generic texture estimation scheme. We investigated the claim that this filter was capable of preserving backscatter texture. To understand if speckle reduction was destroying backscatter texture, we compared the strength of the relationship between forest inventory parameters and image texture as a function of spatial scale for both filtered and unfiltered images. We used Radarsat Fine mode image data: single look resolution is approximately 8.5 m, and pixel spacing is 3 m. Our study area was northern Vancouver Island, B.C., on the west coast of Canada. For the unfiltered data, we found that the ability of image texture to predict the forest parameters decreased as the texture scale increased from 3 to 13 m, suggesting greater information content in the small scale texture. For the filtered data, this relationship was much weaker at small scales and was not a function of distance. Our results suggest that the speckle filter was not retaining small scale texture, which is consistent with the theoretical hypotheses underlying its multiplicative noise model. We also show that there is significant information in small scale SAR image texture that may be used as an adjunct to other spatial information for discriminating tree stands in the temperate rain forest.

To improve the performance characteristics of small unmanned rotorcraft systems based on commercially available radio controlled helicopter components the simulation and optimization framework Qoptr was developed. The framework's simulation modules model main rotor performance in hover using blade element momentum theory (BEMT) and in forward flight conditions employing a blade element theory (BET) approach. The forward flight module incorporates empirical induced inflow models and rigid blade motion. Two software packages based on viscous-inviscid interaction methods were evaluated on their ability to generate the low Reynolds number 2D aerodynamic airfoil performance coefficients required by the simulation modules at conditions applicable to large radio controlled helicopters. The Qoptr hover module was integrated into an optimization scheme using an algorithm from the MATLAB Optimization Toolbox. Starting from a rotor using typical commercial r/c rotor blades the optimization raised the rotor figure of merit from 0.56 to 0.70 by adjusting rotor speed, solidity and the spanwise distributions of blade pitch and chord length.