On the Performance of Filters for Reduction of Speckle Noise in SAR Images off the Coast of the Gulf of Guinea

Remote sensing for monitoring tropical dryland forests: a review of current research, knowledge gaps and future directions for Southern Africa

“…Similarly, there are a number of challenges to analysing and interpreting radar images for tropical forest applications, which include: (1) Difficulty in interpreting radar backscatter, including, for example, speckle, which is unwanted random noise inherent in all SAR images, which may increase measurement uncertainty and make interpretation difficult (Klogo et al 2013); (2) Topography is a major limitation in mountainous regions due to geometric and radiometric effects such as radar shadowing caused by foreshortening and layover when the satellite is not able to illuminate the whole ground surface (Mitchard et al 2009); (3) SAR observations often lack a long-term and dense time series because they demand a relatively high energy provision on satellite platforms. Until recently, satellite-based SAR data for multi-temporal assessments over large areas were constrained by low spatial and temporal coverage at medium resolution, although this now may be overcome with acquisitions from the recently launched C-band Sentinel-1 and L-band ALOS-2 satellite missions (Reiche et al 2016).…”