[alistaira]

For the second, I get the impression that this is less of a case of a building being bathed in EM radiation (as a jammer might) but (excuse my unscientific attempt at this description) several beams of EM radiation creating a superposition at their point of intersection in 3D space.

The latter case would be harder to triangulate as you'd need to have multiple detectors positioned along each beam line in order to determine the range of each emitter.