Capon beamformer for mimo radar applications

Hi,
I'm new to this forums, so I do apologise if the question is not correctly synthesized. I'm working on MIMO radar imaging system and for my dissertation I would like to explain Capon beam-former, that is Mathematically and in my own words. By searching on the topics relevant literature, I would like some advise of where can I find relevant literature which describes it in simplest possible way.
thank you for your time.