• I_Has_A_Hat@lemmy.world
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    14 days ago

    Wouldn’t it be similar to radio waves where we can bounce them off the atmosphere and drastically increase their range?

    • NaibofTabr@infosec.pub
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      14 days ago

      Ah, no. Electromagnetic induction and electromagnetic radiation are related but different - induction doesn’t produce radiation (radio) waves that would travel longer distances.

      It is possible to power a device with radio waves - the most basic crystal radio just drives a speaker using the acquired radio signal. In 1945 the USSR “gifted” a concealed listening device (The Thing) to the US ambassador which worked this way - it was only “on” when an external radio was transmitting the correct frequency, making it very hard to detect. RFID tags also work the same - they don’t require batteries because the chip is activated when the tag’s antenna gets hit by the radio from the scanner.

      This is only practical for very low-power devices, because transmitting high-power radio waves is dangerous.