I am just a half-educated layman when it comes to SAR, which has a very heavy electrical engineering heritage. I hear that one very good technical resource is this book written by Iain Woodhouse [1], but I would be lucky to understand a tenth of it myself.

There is also a very good SAR vulgarisation book written by Tom Ager [2].

[1] https://www.routledge.com/Introduction-to-Microwave-Remote-S...

[2] https://www.amazon.com/Essentials-SAR-Conceptual-Remarkable-...