Sentinel-1 L1 GRD
Level-1 Ground Range Detected (GRD) products consist of focused SAR data that has been projected to ground range using an Earth ellipsoid model. The projection is corrected using the terrain height specified in the product general annotation. GRD products are generated from the following Sentinel-1 imaging modes:
- Stripmap (SM)
- Interferometric Wide Swath (IW)
- Extra Wide Swath (EW)
Ground range coordinates are the slant range coordinates projected onto the ellipsoid of the Earth. The pixel values represent detected magnitude. Phase information is lost. The resulting product has approximately square spatial resolution and square pixel spacing with reduced speckle due to the multi-look processing. The noise vector annotation data set is part of the product annotations and contains thermal noise vectors. Thus users can apply a thermal noise correction by subtracting the noise from the power detected. The thermal noise correction is, for example, supported by the Sentinel-1 Toolbox (S1TBX).
GRD products are available in three resolutions, characterised by the acquisition mode and the level of multi-looking applied::
- Full Resolution (FR), available in SM mode
- High Resolution (HR), available in SM an IW mode
- Medium Resolution (MR), available in SM, IW and EW mode
For the IW and EW GRD products, multi-look is performed on each burst individually. All bursts in all sub-swaths are then seamlessly merged to form a single, contiguous, GRD image per polarisation channel. The data are also available in COG format.
| General | Description |
|---|---|
| Availability / Temporal coverage | Europe coverage: 2014-10 - now World coverage: 2014-10 - now |
| Updates | Systematic continuous ingestion |
| Access interfaces | Data Explorer S3 from cloud environment S3 Remote Transfer |
| Path to repository | /eodata/Sentinel-1/RAW/GRD /eodata/Sentinel-1/RAW/GRD-COG |
| Sensor | C-SAR |
| Sensor Mode | EW, IW, SM, WV |
| Data Type | Unfocused SAR raw data |
| File Format | GeoTIFF |
| Processing Level | LEVEL0 |
| Resto Platform | S1A,S1B |
| Resto Collection | SLC |
| Resto Instrument | SAR |
| Vertical Coverage | 46.5N - 55.0N |
| Horizontal Coverage | 5.0E - 14.6E |