I Can an enclosure surrounding a Tx antenna act as a receiving antenna?

[genekuli]

TL;DR Summary

If I put a metal enclosure, eg. cuboid, around a Tx antenna, can the metal enclosure, since it is completely surrounding the antenna, act as a receiver (a receiving antenna) even if it is not of any specific dimension relating to the frequency of the TX antenna radiation within it?

of course it would all have to be wired up correctly

 

[berkeman]

of course it would all have to be wired up correctly

That's the key point, I believe. How are you going to wire up a metal cuboid to act as an antenna? An antenna develops a receive voltage at its output terminals as a result of the EM radiation generating differential currents and hence differential voltages. A cuboid doesn't have 2 halves like a dipole, and if you try to use it as a monopole with respect to a ground plane, I don't think the Tx antenna inside it will generate any differential currents or voltages with respect to the ground plane.

Do you have a particular application in mind? If you describe the application, we may be able to suggest some antenna geometries that could work. Or is this just a question that came up as you were learning about EM and antennas?

 

[sophiecentaur]

For the 'enclosure' to do other than just reflect the radiated fields, it needs to have a break in it (a slot, for instance) so that an EMF can be detected across it.
So if your enclosure is 'ideal' (silver plated and welded all around) then the transmitting antenna will present to the transmitter as a pure reactance with no resistance. It would give most transmitters a headache as it could deliver no power.

This is one of those irrisistable force meets an immovable object type questions. In real life, the setup can't exist so you'd have to allow some imperfection, like leakage through the enclosure. Once you do that, you can calculate some sort of a real answer.