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Envisat ASAR AP Single-Look Complex L1 [ASA_APS_1P]

Envisat ASAR Alternating Polarisation Mode Single-Look Complex

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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. Interferometric search option is available for relevant collections. 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 EO Catalogue (EO CAT), 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 FAQ page.

New users can register an account on EO Sign In. For further information about the EO Sign In Service you can visit TellUs.

ESA internal users can use their ESAAD account.

Should you need support to access the data, please contact EOHelp.


This product is a complex, slant-range, digital image generated from Level 0 data collected when the instrument is in Alternating Polarisation mode. (7 possible swaths). It contains two CO-registered images corresponding to one of the three polarisation combination submodes (HH and VV, HH and HV, VV and VH).

In addition, the product uses the Range Doppler algorithm and the most up to date processing parameters available at the time of processing. It can be used to derive higher level products for SAR image quality assessment, calibration and interferometric applications, if allowed by the instrument acquisition.

A minimum number of corrections and interpolations are performed on the data in order to allow the end-user maximum freedom to derive higher level products. Complex output data is retained to avoid loss of information. Absolute calibration parameters are available depending on external calibration activities and are provided in the product annotations.

Spatial Resolution: Approximately 8m slant range x approximately 4m azimuth.



Spatial coverage:
90 N, -90 S, -180 W, 180 E
Temporal coverage:
2002-11-15 - 2012-04-08
Date of launch:
Mission status:
Orbit height:
800 km
Orbit type:
Swath width:
5 - 1150 km
High Resolution - HR (5 - 20 m)


Level 1b


Utilisation of this data is subject to ESA's Earth Observation Terms and Conditions.



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