Sentinel-1 SAR GRD: C-band Synthetic Aperture Radar Ground Range Detected, log scaling (COPERNICUS/S1_GRD)

The Sentinel-1 mission provides data from a dual-polarization
C-band Synthetic Aperture Radar (SAR) instrument. This collection
includes the S1 Ground Range Detected (GRD) scenes, processed
using the Sentinel-1 Toolbox to generate a calibrated, ortho-corrected
product. The collection is updated weekly.

This collection
contains all of the GRD scenes. Each scene has one of 3 resolutions
(10, 25 or 40 meters), 4 band combinations (corresponding to
scene polarization) and 3 instrument modes. Use of the collection
in a mosaic context will likely require filtering down to a homogenous
set of bands and parameters. See this article
for details of collection use and preprocessing. Each scene contains
either 1 or 2 out of 4 possible polarization bands, depending
on the instrument’s polarization settings. The possible combinations
are single band VV or HH, and dual band VV+VH and HH+HV:

1. VV: single co-polarization, vertical transmit/vertical receive
2. HH: single co-polarization, horizontal transmit/horizontal receive
3. VV + VH: dual-band cross-polarization, vertical transmit/horizontal
   receive
4. HH + HV: dual-band cross-polarization, horizontal transmit/vertical
   receive

Each scene also includes an additional ‘angle’ band that contains
the approximate viewing incidence angle in degrees at every point.
This band is generated by interpolating the ‘incidenceAngle’ property
of the ‘geolocationGridPoint’ gridded field provided with each asset.

Each scene was pre-processed with Sentinel-1 Toolbox
using the following steps:

1. Thermal noise removal
2. Radiometric calibration
3. Terrain correction using SRTM 30 or ASTER DEM for areas greater than
   60 degrees latitude, where SRTM is not available.
   The final terrain corrected values are converted to decibels via log scaling
   (10*log10(x)) and quantized to 16-bits.

For more information about these pre-processing steps, please refer to the
Sentinel-1 Pre-processing article.