Previously linked question (which is closed but already has answers).

Say we have a type of implanted device in human body (say, ear) used to communicate over a distance. I am thinking about a combination of super-capacitor charged over human body to make this device self-powered.

But transmission over a long distance certainly requires a nontrivial amount of power, and being an implanted device makes this trickier. Currently there are nanoradios and this kind of design but the transmission range are not enough for long-range (say, over 100m or even over 1 mile) communications.

So my question is, can a miniature implanted device in human body transmit information over a long distance, say 100m or 1 mile (or even longer)? What factors would be important and how?

I want the design to be scientific and based on current technology as much as possible.

  • $\begingroup$ Googling for "antenna human implant" or "wearable antenna" would probably give you the information you need; e.g. mistralsolutions.com/blog/… $\endgroup$ Commented Nov 6, 2021 at 16:51
  • $\begingroup$ What information is it transmitting ? $\endgroup$ Commented Nov 6, 2021 at 21:37
  • $\begingroup$ @StephenG For example record voice and transmit it like a walkie-talkie or mobile phone. $\endgroup$
    – RLR
    Commented Nov 6, 2021 at 22:14
  • $\begingroup$ This will depend greatly on the receiver (also in-ear, or a huge dish?) the data rate (human voice (190kb/s), or downsampled voice (like telefone, 10kb/s), or even just transcribed speech in realtime( 100b/s?)) and whether you allow for the antenna to be outside (camouflaged as a hair, e.g) $\endgroup$
    – bukwyrm
    Commented Nov 9, 2021 at 11:05
  • $\begingroup$ Also, 1 mile can be the range on a field, but as soon as you are near even a single bush, the range in that direction may be down to a few meters... are you talking about 1 mile in urban environment, or on a plain? $\endgroup$
    – bukwyrm
    Commented Nov 9, 2021 at 11:17

1 Answer 1


Your enemy is called signal-to-noise ratio, so you will need to have as much signal-boost on your side as possible:

So let's optimize:

  • datarate super low, 100bit per second, able to transmit the content of what you speak (your implant does speech-to-text)
  • Antenna is several cm long
  • You only send short bursts, and not often, but can squander about a Watt on them in return
  • the antenna is not even subcutaneous, but only sub-cuticular, or even camouflaged as a hair
  • you climb a tree for transmission
  • the antennas geometry is directional, and you turn your head juuuust right
  • the receiver has a ham-style antenna

35 Miles

  • $\begingroup$ Thanks! I wonder what would be the (smallest possible) size of this entire setup? $\endgroup$
    – RLR
    Commented Nov 10, 2021 at 0:34
  • $\begingroup$ If this has been developed with no thought as to budget, the biggest thing will be the capacitor, which scales with the time you'd like to talk. Also, this is the flimsiest part (conceptually), because i am not aware of a cap that could currently do what needs to be done (store harvested energy effciently over a day, then release in a minute) - say we defeat leakage current, and say we get 100Wh/l, and we need 1Wminute, we'd be at <2ml , so the whole thing would be as big as two lego-person-heads. You can go much smaller by giving it a disposable battery (10 times smaller) $\endgroup$
    – bukwyrm
    Commented Nov 10, 2021 at 6:29
  • $\begingroup$ Thanks. I see. But disposable battery means not rechargeable right? I guess a powerful and rechargeable battery at THAT small size isn’t quite practical? $\endgroup$
    – RLR
    Commented Nov 10, 2021 at 6:58

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .