Improved multilook technique applied to SAR images
نویسندگان
چکیده
The multilook technique used in synthetic aperture radar image formation consists in adding incoherently M looks. As these looks can be obtained in their complex form and are correlated, the phase and correlation informations should be taken into account in the speckle reduction process. In this paper, we propose an improved multilook technique based on the use of these two informations. We apply it on SAR images displaying ship wakes. Our technique consists in enhancing a speci c texture in the image, using a set of lters matched to it, while simultaneously reducing speckle. The lters are applied on each look, and the resulting images are projected onto a particular basis. The nal image is constituted by the quadratic sum of the processed looks, after their projection on the same geographic plane. Illustrative results as images comparison and analysis will show the e ectiveness of the proposed algorithm.
منابع مشابه
Compressed Sensing SAR Imaging with Multilook Processing
Multilook processing is a widely used speckle reduction approach in synthetic aperture radar (SAR) imaging. Conventionally, it is achieved by incoherently summing of some independent low-resolution images formulated from overlapping subbands of the SAR signal. However, in the context of compressive sensing (CS) SAR imaging, where the samples are collected at sub-Nyquist rate, the data spectrum ...
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