The Sarscape help for SBAS says:
Input file list
Input files (_slc) to be used. This file list is mandatory.
So you must use SLC images and you pass the list as input to SBAS from the Connection graph. There are many settings you can use to help import your data. You might find the SBAS tutorial from the Sarmap website useful:
http://www.sarmap.ch/wp/i...p/software/sarscape/