Imaging the Gas Giants

I know little to nothing about radar imaging, or any other means (correct me if you know). What would be a way we could use radar to map out what is beneath the thick layers of gas on our gas giants? To find a liquid or solid core perhaps. What technologies would we have to utilize and is that possible?

impossible - the thick clouds are WAY too thick for radar to penetrate. however, the way that people draw conclusions about the interior of that stuff is through sensitive measurements of the gravitational field. if you can figure out J2, J4, etc higher order terms that describe the mass irregularities in a body, you can deduce a lot about the interior.