Specialisation Documents Organisation

During the PDR-C collocation meeting it was agreed to analyse if one SAFE Specialisation Document per each product type (at different levels) is better than having just one single specialization document for all instrument products (PDR-C_A09).

The attached document “Specialisation Documents Organisation trade-off” (PDGS-SAFE-GMV-TN-12/0194) provides the analysis and conclusions reached on this topic.

All your comments will be appreciated.
Best Regards.

Adrián Sanz (GMV)
LTDP SAFE Project Manager

Re: Specialisation Documents Organisation


I am not convinced about the recommended alternative. On the one hand, the PDSC instrument classes are not widely agreed/recognized, they are subject to change, and so it is a risk to consider them as the main driver for the specialisation organization. Note for example that the latest version of the PDSC document (4.0) does not contain the section that the trade-off document refers to (section 4.1), which is an indication of the continuous evolution of the document. It is certainly, a priori, a good idea to organize information according to the instrument category, but in this context it does not lead to a reduction in the size of documents (e.g. all the ENVISAT ASAR product types of all levels will still be together) and the main idea behind this organization (across-mission applications for similar products) cannot be easily transported to the documentation because it would lead to even larger documents (e.g. a single SAFE specialisation for SAR/ASAR products from ENVISAT and ERS). The underlying organization of the standard also does not favour across-mission usage (a SAFE (A)SAR product from ENVISAT is different from a SAFE SAR product in ERS).

I also don't think that any one of the three alternatives is clearly better than the others (A.3 is better for a criterium which only applies to it), but there are things in all of them which are already an improvement w.r.t. SAFE 1.3:

- a common mission specialisation grouping mission information that otherwise would be redundant (this has the important advantage of introducing a clear place to include the processing chain information)
- well defined criteria to organize the documentation

If we take these two aspects and strive to reduce the size of specialisation documents by simply removing unnecessary content (we should review that) and reorganizing information, I think we have a workable solution. Between A.1 and A.2 I think A.1 gives us a better chance of having relatively short documents (even if there will be more of them). A.2 is not that different from what are the current SAFE 1.3 specialisation documents.

Finally, I don't remember if (what?) we said something about whether this organization would be a requirement or just a recommendation. I think it is difficult to impose it as a requirement, also given the heterogeneity of missions.


Re: Specialisation Documents Organisation

The control book organisation may take into account also the mission/sensor/sensor mode classification which could solve the issues with sensors having huge control books like ENVISAT ASAR.

Re: Specialisation Documents Organisation

Thank you for your feedback.

We will consider your comments for the organisation of the documents. The proposed final approach will be the following:

  • To modify alternative A.3 as suggested, including the mission name as part of the Document Reference (e.g. C1-V2-ENVISAT-ASAR) for each instrument specialisation document.
  • To recommend the use of alternative A.3 (aligned with the “European LTDP Common Guidelines” instrument classification)
  • To allow a sub-division per “sensor mode” or “product level” that may reduce the size of each control book.
  • To propose as optional alternative A.1, but explaining that for each mission the organization A.3 or A.1 should be decided and respected in the overall specialisation.

Adrián Sanz (GMV)
LTDP SAFE Project Manager

The original document is available at