I was exploring this satellite's payload characteristics on ESA's website and I saw that it's azimuth resolution varies a lot. For example azimuth resolution for IW mode is 22m (https://sentinel.esa.int/web/sentinel/user-guides/sentinel-1-sar/resolutions/level-1-single-look-complex). But this is very weird, and I can't wrap my head around why that is, since Sentinel 1a is a SAR, therefore it's azimuth resolution should be L/2 (L being the length of the antenna) or 6.15m (since it's antenna is 12.3 meters i believe).
Why is its resolution different?
I assume this will have something to do with the doppler shifts but I can't see it in my head.