3 ms·

AFAIK the only reason WiFi sticks to 2.5/5 GHz is regulation. Same for microwaves and other appliances. Those are the only two “free use” bands in the spectrogr

AFAIK the only reason WiFi sticks to 2.5/5 GHz is regulation. Same for microwaves and other appliances. Those are the only two “free use” bands in the spectrogram in most countries. Operating outside of them requires expensive fees and heavy scrutiny. It will be interesting to see how they sort that out...

wnevets 8y ago
The first step is probably building a HQ near Washington DC
aftbit 8y ago
There are a number of other "free use" bands (called ISM bands). See wikipedia[0] for more information. Some of the most interesting ones are at 433 MHz (Europe), 902 MHz (US only, often used for old cordless telephones), and 24 GHz (worldwide). We have microwaves to thank for the 2.4 GHz band (and maybe 900 MHz as well)[1]. 0: https://en.wikipedia.org/wiki/ISM_band https://en.wikipedia.org/wiki/ISM_band 1: https://web.archive.org/web/20160304061338/https://www.itu.int/dms_pub/itu-s/oth/02/01/S020100002B4813PDFE.pdf https://web.archive.org/web/20160304061338/https://www.itu.i... (see page 464)
dboreham 8y ago
For completeness: there is also a 900MHz band, and 24GHz and 60GHz bands. Microwaves I assume refer to ovens, which use a frequency related to the nature of the water molecule. The 2.4GHz ISM band supposedly exists because commercial and military users didn't want to deal with interference from ovens.
- TheSpiceIsLife 8y ago
  > Microwaves I assume refer to ovens, which use a frequency related to the nature of the water molecule. They work using Dielectric Heating. Water, fat, and other substances in the food absorb energy from the microwaves in a process called dielectric heating. See: https://en.wikipedia.org/wiki/Microwave_oven#Principles https://en.wikipedia.org/wiki/Microwave_oven#Principles Also: https://en.wikipedia.org/wiki/Dielectric_heating https://en.wikipedia.org/wiki/Dielectric_heating
- dbcurtis 8y ago
  No, at the time the regulations were written, people were think terrestrial and Earth-to-space links, and the high absorption of 2.4G by atmospheric moisture and moisture in foliage makes it a poor choice for these kinds of paths.

wnevets 8y ago

The first step is probably building a HQ near Washington DC

aftbit 8y ago

There are a number of other "free use" bands (called ISM bands). See wikipedia[0] for more information. Some of the most interesting ones are at 433 MHz (Europe), 902 MHz (US only, often used for old cordless telephones), and 24 GHz (worldwide). We have microwaves to thank for the 2.4 GHz band (and maybe 900 MHz as well)[1]. 0: https://en.wikipedia.org/wiki/ISM_band https://en.wikipedia.org/wiki/ISM_band 1: https://web.archive.org/web/20160304061338/https://www.itu.int/dms_pub/itu-s/oth/02/01/S020100002B4813PDFE.pdf https://web.archive.org/web/20160304061338/https://www.itu.i... (see page 464)

dboreham 8y ago

For completeness: there is also a 900MHz band, and 24GHz and 60GHz bands. Microwaves I assume refer to ovens, which use a frequency related to the nature of the water molecule. The 2.4GHz ISM band supposedly exists because commercial and military users didn't want to deal with interference from ovens.

TheSpiceIsLife 8y ago
> Microwaves I assume refer to ovens, which use a frequency related to the nature of the water molecule. They work using Dielectric Heating. Water, fat, and other substances in the food absorb energy from the microwaves in a process called dielectric heating. See: https://en.wikipedia.org/wiki/Microwave_oven#Principles https://en.wikipedia.org/wiki/Microwave_oven#Principles Also: https://en.wikipedia.org/wiki/Dielectric_heating https://en.wikipedia.org/wiki/Dielectric_heating
dbcurtis 8y ago
No, at the time the regulations were written, people were think terrestrial and Earth-to-space links, and the high absorption of 2.4G by atmospheric moisture and moisture in foliage makes it a poor choice for these kinds of paths.