There are hundreds, if not thousands, of RF signals all around us from those at VLF frequencies to microwave frequencies and I suspect if you set up a very long random length of wire as an antenna, there would be a resulting induced electrical signal that is the sum (and differences) of all those various RF waves hitting it. My question is, does a single composite wave exist in space inducing a similar signal in the antenna or is the signal in the antenna only the composite resultant of a multitude of discrete radio waves hitting the antenna? Does the superposition occur whenever two or more waves meet anywhere in space resulting in a composite wave, or only if there is antenna to receive them? Similarly, I am familiar with Young’s two slit experiment from looking at various websites and I think I understand destructive and constructive interference, but again, in the absence of the white card to show the bands of interference, is there a single resulting composite wave where the waves meet as the result of superposition or are they two separate waves until you provide the card? My gut feel is that a composite wave results anywhere two or more waves meet and the antenna and card are just means of detecting what the instantaneous value of that composite wave is for that particular location at that particular point in time, but I would love to know for certain. And more importantly, understand why if that is not the case.