The default is the 2.4Ghz r/c connection, but I understand that the recent firmware release now can swap to the 5.8Ghz link used by the camera (which is a standard WiFi connection) if reception is bad. There aren't many technical details of how the link is managed between the two separate radio components, other than that both can be used to control the Typhoon. I'm not aware of anyone who's done much to test the actual behaviour.