To me this looks like good old circular polarization.
This is apparently something new, not sure what though - it's not something I ever learned about with photons.
This is known as MIMO transmission, see https://en.wikipedia.org/wiki/MIMO for details (also has the capacity formula).
What these people call "vortex wave", is just precoding/decoding done in a fixed way using fixed antennas. But with non-line-of sight channels and moving sender/receiver you will need dynamic MIMO coding anyways. This is already implemented in LTE (2 antennas in the handset, 4 at the base station, AFAIR).