None found.
Not applicatable.
Stealth and other aircraft block out cosmic background radiation as they move through the sky. This can be detected and tracked.
These aircraft must duplicate the radiation that they have blocked out, and this when radiated, will make them almost impossible to detect by its loss of presence.
None.
Aircraft would be fitted with antennae to receive the cosmic radiation and then it would be electronically reproduced by the aircraft's avionics to replace the blocked natural radiation.