Importing ERS CEOS data

I downloaded ERS-2 data from the following site.
https://search.asf.alaska.edu/#/

In case of L1 data, the data consists of files with the formats ‘.L’, ‘.P’, and ‘.D’.
As the ASF document, L and P are metadata, and the ‘.D’ is image data.
However, in SNAP, I cannot import any file.
‘Import -> SAR Sensor -> ERS CEOS’, there is nothing that I can click in the data folder.

How can I import and read ERS-2 data?

Thank you

The Level-1 ERS products from ASF are not compatible with SNAP.

I suggest to search the ESA TPM archive: https://esar-ds.eo.esa.int/oads/access/collection
After registration, it allows you to download different types of Level-1 products

grafik

  • IMS is single look complex
  • IMP is ground range detected
  • IMM is lower resolution*

All are fully compatible with SNAP (use the .E1/.E2 import)

*IMM corresponds to the L1 products in ASF, but it’s not the native resolution:

I appreciate your reply.
I found that some information is different between that from ASF and that from ESA TPM archive.
First, the file names are different. (actually, I think this is not that very important)
The more critical thing is the frame numbers are different when I compared two data look like the same. (they have same orbit number and acquisition time)

I wonder why they have different parameters even though they were achieved from same satellite, and which one is right.

I think this is related to how the data was acquired. The ASF archive only hosts a fraction of the totally available data. They processed the raw data themselves and defined own product description.
In contrast, the ESA archive is widely complete and consistently structured and documented.

Synonymous terms like “relative orbit”, “track”, ect. are not used consistently between both portals as well.

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Thank you. I understand.
I have one more question about ESR data.
I downloaded ERS-2 L0, L1 IMS, L1 IMP data.
The format of all data is ‘.E2’, which is not familiar with me.
L1 data open in SNAP, however, as I know, SNAP does not deal with L0 data

Then, how can I read L0 data with ‘.E2’ format?
I tried with MATLAB ‘fopen’ function, but it did not work.
I’m not sure whether asking this question here, but if you can, I would appreciate your help.

Thank you

L0 is raw and unfocused data, neither SNAP nor Matlab can read it as a raster. I suggest to use the L1 data.

If you really want to focus the L0 data yourself, you can try this tutorial: https://eo-college.org/resource/focusing-matlab/

Thank you very much. It is really helpful