Hi.

What harmless material attached to a moving object or animal, could be useable for tracking by detecting its emission of particles, waves, radiation or anything from the largest possible distance by modern sensing technology, without being electronic at all ?

 

Sort of some tracer to locate/find which in thousands of packages or vehicles passing by carries such material inside ?

 

Like the body heat detection used from aircraft while searching for lost persons in a forest, but not being obstructed by common materials, trees, buildings, and producing a recognizable signature.

 

Miguel

Thats what RFID is for. There is no passive non-electronic emitter that would meet your specification.

I didn't think RFID would get out past a metallic chassis. Maybe in the high frequency range, perhaps ?

 

Externet, the idea is simply to use a radio transponder beeping out a specific signature. I believe that's essentially what RFID involves but I'm not really cartain.

Well then you mount it outside of any shield. They can be made rather small and flat for surface mounting.