Can you share some more links to the radar technology you mention with high resolution and discrimination functionality? I am interested in performing more research on this topic. I'm familiar with several phased array radar platforms, so I might be aware of this specific implementation, but perhaps not!
As I understand it it's the algorithms that analyze the radar data that are the secret (literally) sauce. I didn't work on any of that. I just plumbed various data from A to B. I don't know much other than it was really damned good for being "legacy" at the time I was working there.
As the long slow march of progress continues it may come down in cost enough to be viable on vehicles.