ATSC 3.0 uses an IP data platform for much greater flexibility in usage than current standard broadcast systems and users of the system can send out several video streams of varying bandwidths at the same time, while also adding in additional data streams of other types. In other words, ATSC 3.0 is powerful and exactly the kind of system that 4K could flow smoothly through.
Source: Over-the-Air 4K TV broadcast demo coming to CES 2016 –