"What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years."
The dielectric medium is considered a passive component and requires energy input to emit electrons.
Otherwise I think I understand the basic concept. I can only imagine its application in transmission of a radio signal. The reception is still going to be limited by the capture area of physical antenna.
"What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years."
You're right, it doesn't make sense as written. A noun (dielectric "medium" in this case) does not "result in the emission" of anything. That would require a causal verb of some sort, which is missing from this sentence.
>> The reception is still going to be limited by the capture area <<
What about ferrite-core loopsticks? They occupy a tiny space but pick up a lot of signal.