4 ms·
Very nice. I'd like to see one like this that uses frequencies that can pass through 200m of rock. Obviously the radio frequency will need to be much, much lowe
by krunck 1y ago
Very nice. I'd like to see one like this that uses frequencies that can pass through 200m of rock. Obviously the radio frequency will need to be much, much lower (https://en.wikipedia.org/wiki/Through-the-earth_communications https://en.wikipedia.org/wiki/Through-the-earth_communicatio...). Why, you ask? Cave rescue situations.
- teleforce 1y agoIt's not only lower frequency, it also need robust wireless modulation that can work with very limited LoS where LoRa perform badly. LoRa is pretty much useless in your use cases. Currently we're working on a new wireless modulation that has much higher bandwidth (similar to HaLow) but 1000x better in BER performance than LoRa in limited LoS propagation model based on simulation. If we can get 100x improvement in real world testing for the high bandwidth version I'm more than happy. Our Japanese collaborators has tested the lower bandwidth version similar to LoRa bandwidth and frequency, and it work fine inside a bunker. If you're interested perhaps we can collaborate on testing the solution. Already proposed to IEEE as new wireless PHY modulation but to no avail yet.