Analysis method for speckle in radar imagery systems
Abstract
Expressions for the speckle spectrum of airborne radar imagery systems related to the autocorrelation function of the position dependant echo strength of the soil were derived. In the characteristics of speckled images obtained with coherent microwaves, statistical information concerning the object texture, relative to the sensor, is stored. After nonlinear elaboration by a quadratic detector, the intensity is written as the sum of median effect and speckle fluctuations. Based on a Gauss antenna diagram and pulse function, an expression for the median effect spectrum, related to the echo strength spectrum, is found via a spatial low pass filter. Speckle spectrum expressions in x- and y-direction related to the echo dispersion function of the surface are found.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- July 1985
- Bibcode:
- 1985STIN...8619505P
- Keywords:
-
- Microwave Scattering;
- Normal Density Functions;
- Radar Imagery;
- Remote Sensing;
- Speckle Patterns;
- Textures;
- Autocorrelation;
- Low Pass Filters;
- Microwave Sensors;
- Point Spread Functions;
- Pulse Radar;
- Side-Looking Radar;
- Surface Properties;
- Synthetic Aperture Radar;
- Communications and Radar