Available with Standard or Advanced license.
This workflow provides the information and requirements for adding RADARSAT–2 data to a mosaic dataset.
Radar data is collected using an active microwave sensor which can result in backscatter (including speckle) depending on the properties of the earth's surface, such as shape, angle, roughness, and water. For example, a radar image taken over a dense forest may produce an image with high backscatter, whereas a wide roadway may produce low backscatter.
Calibration of these backscatter values is necessary when comparing radar images acquired using different sensors, modes, or processors. Three output scaling lookup tables (LUTs) are included with every RADARSAT-2 product, except for SSG (Map Image) and SPG (Precision Map Image) products. These LUTs allow one to convert the digital numbers found in the output product to sigma-nought, beta-nought, or gamma-nought values (depending on which LUT is used) by applying a constant offset and range-dependent gain to the SAR imagery. Radiometric calibration is applied on the radar imagery to view its actual representation. The following radiometric calibration options are supported for RADARSAT–2 datasets.
- Beta-nought—This option represents radar brightness.
- Sigma-nought—This option represents radar backscatter.
- Gamma—This option represents backscattering coefficient normalized by the cosine of the incidence angle.
- None—Uncalibrated radar data.
- Create a mosaic dataset.
- In the Catalog window or ArcCatalog, right-click the mosaic dataset and click Add Rasters.
The Add Rasters to Mosaic Dataset tool opens.
- Select RADARSAT-2 from the Raster Type drop-down list.
- Click the Edit Raster Type Properties button .
The Raster Type Properties dialog box is opened. Here, you will enter specific information about the radiometric calibration and speckle filter.
- Click the General tab.
- Select a processing template.
- Raw—This is the default and does not apply any speckle filtering.
- Despeckle—Applies a speckling filter.
- Click the Radar Processing Options tab.
- Optionally, select a method from the Radiometric Calibration drop-down box.
Radiometric calibration is applied irrespective of the processing templates selected.
- None—Uncalibrated radar data. This is the default.
- Beta-nought—This option represents radar brightness.
- Sigma-nought—This option represents radar backscatter.
- Gamma—This option represents backscattering coefficient normalized by the cosine of the incidence angle.
- Optionally, if you need a specific polarization from an input with more than one, you can specify the Polarization Type.
The following are the polarizations available with RADARSAT-2 products:
- HH—The radar signals are transmitted horizontally and received horizontally.
- VV—The radar signals are transmitted vertically and received vertically.
- HV—The radar signals are transmitted horizontally and received vertically.
- VH—The radar signals are transmitted vertically and received horizontally.
- If you selected the Despeckle processing template, modify the Speckle Filter options.
For more information on specific filter types and parameters, see Speckle function.
- Click OK to close the Raster Type Properties dialog box.
- Click the Input drop-down arrow and select Workspace.
- Click the
browse button , select the folder with your RADARSAT-2 data, then click
Add. Alternatively, you can drag and drop the folder into the Source parameter on the dialog box.
The workspace is added to the Sourcelist.
- If you won't be adding any more data to the mosaic dataset, check Update Overviews.
- If statistics or pyramids don't exist for your data, expand the Advanced Options, and check Build Raster Pyramids and Calculate Statistics.
- Click OK to run the tool and add the data to the mosaic dataset.