EO Sign In Authentication (Open): This collection is openly accessible but requires users to log in with an EO Sign In account (a system used across ESA Earth Observation services) before any downloads can proceed.

Access Steps:

1. Create or log in to EO Sign In account.
2. Go to the Dissemination Service or Exploring Earth service
3. Browse or search for the collection. 
4. Download product.

The ESA (A)SAR On-The-Fly (OTF) data processing and dissemination service allows end-users to gain direct access to the (A)SAR archive from the ERS-1, ERS-2 and Envisat Missions.

The data is collection based and allows data browse and download through the treeview as well as via geographical catalogue search based on area of interest and metadata. Data download is available via HTTPS, including bulk download functionality. ESA internal users can use their ESAAD account.

Envisat products can also be discovered through ESA's Exploring Earth service, which allows users to browse and download products among the available datasets from ESA and Third Party Missions and instruments, using various criteria (spatial, temporal).

For information on the (A)SAR On-The-Fly service please refer to the OTF User Manual.

This ASAR Alternating Polarisation Mode Precision product is generated from Level 0 data collected when the instrument is in Alternating Polarisation Mode (7 possible swaths). The product contains two CO-registered images corresponding to one of the three polarisation combination submodes:

• HH and VV,
• HH and HV,
• VV and VH.

This is a stand-alone multi-look, ground range, narrow swath digital image generated using the SPECAN algorithm and the most up to date auxiliary information available at the time of processing. Engineering corrections and relative calibration (antenna elevation gain, range spreading loss) are applied to compensate for well-understood sources of system variability.

Generation of this product uses a technique to allow half the looks of an image to be acquired in horizontal polarisation and the other half in vertical polarisation and processed to 30-m resolution (with the exception of IS1).

Absolute calibration parameters are available depending on external calibration activities and are provided in the product annotations.

Spatial Resolution: 30 m ground range x 30 m azimuth.