It's not too crazy, if you're familiar with comms systems.

The ability to do this is a necessity for a comm system working in a reflective environment: cancel out the reflections with an adaptive filter, residual is now a high-pass result of the motion. It's the same concept that makes your cell location data so profitable, and how 10G ethernet is possible over copper, with the hybrid front end cancelling reflections from kinks in the cable (and why physical wiggling the cable will cause packet CRC errors). It's, quite literally, "already there" for almost every modern MIMO system, just maybe not exposed for use.