RADIO INVERSION

Ducting ...

occurs when radio frequency (RF) waves are trapped in a 'duct' because of temperature and humidity profiles in the atmosphere. 

Refractivity profiles ...

are profiles that describe ducting in the atmosphere, and can also be used to help initiate forecast models. 

Radio Inversion ...

is a software application that measures power levels of various signals and retrieves the refractivity profile.   It maps out ducting.  Radio Inversion can run from AIS signals, radar signals, DTV, and other similar RF signals. Radio Inversion monitors signals-of-opportunity and maps ducting.