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Published on: August 5, 2009
Generation of non-Rayleigh speckle distributions using marked regularity models
1SVS Inc., Albuquerque, NM.
Summary
The marked regularity model explains non-Rayleigh speckle distributions by considering scatterer placement, unifying previous models and offering a more intuitive description of spatial scattering. This model accurately represents various sparse scattering conditions.
Area of Science:
- Physics
- Optics
- Signal Processing
Background:
- Speckle patterns in coherent imagery typically follow a Rayleigh distribution.
- Deviations from Rayleigh distributions occur with few scatterers or periodic arrangements.
- Existing models (K, Rician, homodyned-K) assume random scatterer phases.
Purpose of the Study:
- To investigate the marked regularity model for describing speckle amplitude distributions.
- To demonstrate the model's ability to generate non-Rayleigh distributions.
- To explore the model's capacity for representing sparse scattering conditions.
Main Methods:
- Modeling scattering in 1D using a stationary renewal process.
- Defining interscatterer distances from a gamma distribution.
- Allowing for correlated scatterer amplitudes in space.
Main Results:
- The marked regularity model can generate all previously observed non-Rayleigh distributions (K, Rician, homodyned-K).
- Specific conditions for generating different distributions were identified.
- The model effectively describes sparse scattering scenarios.
Conclusions:
- The marked regularity model provides a unified framework for speckle amplitude distributions.
- It offers an intuitive understanding of scatterer spatial placement.
- This model enhances the analysis of coherent imagery with non-ideal scattering conditions.
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