The answer is that likely all the above are used. Asking for “what signal it is detecting” might be better asked from a “what is the greatest signal bearing in

The answer is that likely all the above are used. Asking for “what signal it is detecting” might be better asked from a “what is the greatest signal bearing information” being used… which would help in averting attacks. This kind of stuff could be real menacing in all sorts of public places like airports, coffee shops and etc.