
IoT Radio – Batteryless very cheap radios - spenrose
http://web.stanford.edu/~arbabian/Home/IoT_Radio.html
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wyager
"Just as such devices had done through all of human history, these located one
another in geometrical space -- a simple exercise, nothing more than time-of-
flight computation. [...] They made great spy devices [...] Localizers were by
their nature a type of computer network, in fact a type of distributed
processor."

\-- A Deepness in the Sky

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peter_l_downs
One of my favorite books!

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3rd3
Previously on HN:

[https://news.ycombinator.com/item?id=8294240](https://news.ycombinator.com/item?id=8294240)

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empressplay
Made me think of crystal radios for some reason:
[http://en.wikipedia.org/wiki/Crystal_radio](http://en.wikipedia.org/wiki/Crystal_radio)

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polskibus
Interesting. Does anyone know how this technology compares to passive antennas
in RFIDs?

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Stwerp
There was an article the other day posted on this. It operates at 24 and 60
ghz whereas most RFID is in the UHF (900 MHz band). This radio harvests energy
to run an oscillator and actively transmits data whereas RFID only reflects
back power (no active rf transmission). Also, this device require a fairly
massive (42 dBm / ~20 watts rf) for a few cm operating distance compared to
RFID which achieved several meters of distance using 36 dBm / 4 watt
transmitters. The biggest achievement is the size reduction. In the previous
HN thread, someone poured out that this is academically very interesting, but
probably practical.

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tlrobinson
Did you mean "probably impractical"?

