Building custom data for snap

Hi all,
I am working on an airborne radar and I would like to be able to load my data into SNAP. My data are in slant range and I know the positions of my plane. How to build a data product with the mandatory information necessary to import it in SNAP? I would like to use for instance the Terrain Correction tool, but all other tools like speckle filtering could be interesting for me.
My data have been processed using python and I have used GDAL to produce GeoTIFF data. The point is to add information to the data about the position of the plane for SNAP to be able to apply terrain corrections.
Thanks in advance,

You would need to start by creating a custom reader that imports your GeoTiff plus any extra metadata. The terrain correction requires orbit state vectors with position and velocity, slant range to ground range coefficients and start/end times. The orbit gets interpolated assuming a smooth orbit which may not be the case from airborne.

Thanks for you very quick answer!
I will have a closer look to the documentation about writing a custom reader. Any advice about the location of a good documentation for that?

Hi Paul,

probably this wiki page can help you. How to create a new product reader.

You can also look at the examples in the snap repository. Either snap-engine or one of the toolboxes, like s1tbx.