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Communication by means of modulated Johnson noise (https://www.pnas.org)

47 points by austinallegro 3 days ago | 23 comments | View on ycombinator

chicken-stew about 7 hours ago |

I’m away from computer so only skimmed the article until I noticed they use the ADG90x RF switch family.

IIRC that family has a single positive supply rail, and they make a nagative rail internally. The advantage is easy of implementation but you also inject some noise depending on switch position. Is this dealt with in the pub?

mitxela about 6 hours ago |

This is extremely strange. Shouldn't this be impossible by the second law of thermodynamics?

Receiving more energy when a resistor in thermal equilibrium is connected to an antenna seemingly implies that energy gets transferred from an antenna with a resistor to a an antenna without a resistor, even at thermal equilibrium.

Maybe we'll later find it's an experimental subtlety, like the faster than light neutrinos.

pockybum522 about 8 hours ago |

Magic, got it.

(I am floored that this works. This is amazing.)

analog8374 about 3 hours ago |

A cacophony of meaty slaps in morse-code.

sweetlimetea about 5 hours ago |

[dead]

frumiousirc about 6 hours ago |

> the maximum achievable throughput is 26 bps at 1.5 m and goes down to 22 bps at 4.5 m.

And when there are more than one transmitters in real world conditions instead of anechoic chamber?

It's cool and all and if this work is for it's own sake, for the sake of research, no issues. But otherwise, I struggle to think of practical use cases. I grant that my imagination may be deficient.