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by amscanne 4375 days ago
Isn't your math off?

Due to path loss, rx signal is 1e-10mW => -100dBm, not -10dBm.

Plug into the formula and we have a maximum theoretical bound of ~ 0.14 bits/second, or one byte every 42 seconds.

2 comments

I switched from W to dBm at the last minute, so there might be mistakes. Anyway, I think it ends up being feasible, because you have some play with transmit power, the noise floor, reflections, and a better antenna, which will all change your number by a few 10s of dB in whatever direction you choose.

Definitely not the worst startup I've seen on HN. I think they can make something useful, since their goal is quite modest.

Even 1 byte every 42 seconds would be very useful for many types of sensors.
That's with the transmitter on 100% of the time.