Hierarchical scattering models
Abstract
The most familiar descriptor of multi-scale structure in continuous scattering media is the power law spectrum which characterizes hierarchical or fractal behavior. The mathematical and phenomenological implications of adopting such models in scattering calculations will be discussed with particular reference to the statistical properties of amplitude scintillation generated by a phase changing screen or diffuser. A brief summer of results obtained when the phase itself is a Gaussian random fractal will be followed by a more detailed review of the case when the phase gradient is fractal. This last model is not only more realistic for fluid systems subject to diffusive or other smoothing effects, but is also amenable to mathematical and numerical analysis. The geometrical optics contribution to the scattered intensity pattern is particularly easy to calculate and a number of results for the statistics of ray density fluctuations will be presented.
- Publication:
-
In AGARD
- Pub Date:
- March 1988
- Bibcode:
- 1988sprm.agarR....J
- Keywords:
-
- Hierarchies;
- Mathematical Models;
- Scattering;
- Wave Scattering;
- Fractals;
- Power Spectra;
- Probability Density Functions;
- Random Walk;
- Communications and Radar