4 ms·
I didn't see Mhz one time in the article and frequency only once with no numbers. 2.8km... is that line of sight? This article is beneath HN. Link to the pap
by ryanmarsh 9y ago
I didn't see Mhz one time in the article and frequency only once with no numbers.
2.8km... is that line of sight?
This article is beneath HN.
Link to the paper: http://longrange.cs.washington.edu/files/loRaBackscatter.pdf http://longrange.cs.washington.edu/files/loRaBackscatter.pdf
- tinix 9y agoYou can't look at that trace antenna and guess the frequency? Obviously it's ISM band, and these researchers are in the United States. Does it really need to tell you that it's ~900MHz?
- bsder 9y agoYes, actually, it does. The green PCB looks more like a 2.4GHz antenna to my eye. The epidermal patch is much longer so looks like 900MHz to me. And there is also 27MHz for ISM. The lower the frequency, the further it tends to go. https://en.wikipedia.org/wiki/ISM_band https://en.wikipedia.org/wiki/ISM_band