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My understanding is that the electric fields are primarily what is used in communication technology and what most antenna design based around. And I am aware of loop antennas that act as an induction coil for the magnetic field component of the electromagnetic wave. And that the and magnetic fields travel together orthogonal to each other.

I am curious about what other technology/systems there are that primarily relies on magnetic fields for communication and/or remotely interacting with devices? And what may be some of the limitations and advantages, in comparison to that of electric fields use for antennas?

Dave
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We do have tools to measure the magnetic field so in theory we should be able to use it to transmit data. The reason it is not used over the typical method is that the magnetic field strength is very small compared to the electric field strength. \begin{equation} B=\frac{E}{c} \end{equation}

See hypertonix below or here to see why my reasoning above was wrong.

So the electric field and magnetic field have the same strength. The reason we use the electric field is that it interacts strongly with charged mono-poles (electrons), and there are a bunch of them around. The magnetic field would interact strongly with magnetic charged mono-poles. Though it seems very unlikely that magnetic mono-poles exist and the smallest component is more likely a magnetic dipole which clearly does not interact as strongly with the H-field. So, it's the electric field that dominates the interaction of e-m waves with matter.

Finesagan
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