heLeesigmafilterwasdevelopedin1983basedonthesimpleconceptoftwo-sigmaprobability,anditwasrea-sonablyeffectiveinspecklefiltering.However,deficiencieswerediscoveredinproducingbiasedestimationandinblurringanddepressingstrongreflectedtargets.Theadvancementofsyntheticapertureradar(SAR)technologywithhigh-resolutiondataoflargedimensionsdemandsbetterandefficientspecklefilteringalgorithms.Inthispaper,weextendandimprovetheLeesigmafilterbyeliminatingthesedeficiencies
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