Comment on Why don’t wireless connections (WiFi, Bluetooth, etc.) use anything between 2.4Ghz and 5Ghz?
kersploosh@sh.itjust.works 1 week ago
2.4 GHz and 5 GHz are both “ISM bands.” These are frequencies that regulators have set aside for unlicensed use.
Fun fact: 2.4 GHz is free to use because of microwave ovens. Microwaves are really noisy around 2.45 GHz. Rather than try to regulate their radio emissions, or make people license their kitchen appliances as radio transmitters, the FCC allocated that patch of spectrum for free use. Any device that can tolerate the noise can use that bit of the radio spectrum.
scheep@lemmy.world 1 week ago
Ah so the stuff in between that has things like radio stations?
edgemaster72@lemmy.world 1 week ago
I’m not sure what exactly you mean by “in between” here (between 2.4 and 5 GHz?), but commercial radio in the US is at much lower frequencies than wifi bands. AM radio is typically measured in KHz (the range is something like 600-1400, I can’t be bothered to look it up), while FM radio is in MHz (around 87-108 MHz).
kersploosh@sh.itjust.works 1 week ago
Not like commercial AM/FM radio stations playing music, but radio in the more general sense. 5G cell phones and satellite-to-earth communication systems use that frequency range, for example.
scheep@lemmy.world 1 week ago
makes sense, using WiFi with those frequencies would make it noisy and clogged up, esp. in crowded cities
Successful_Try543@feddit.org 1 week ago
Some parts of the spectrum in between 2.4 and 5 GHz are used by the mobile communication standards LTE and 5G (also higher frequencies). GSM, DVB-T, and FM radio operate at lower frequencies.
scheep@lemmy.world 1 week ago
ah that makes sense
bobs_monkey@lemm.ee 1 week ago
But, the key takeaway there is that those portions of the spectrum where mobile bands are are restricted to those uses. 2.4 and 5 are “free bands,” in which any device can use them (assuming compliance with FCC part 15 in the US). If I built a device and operated it at say 4.3GHz, I’d get in big trouble once found.
Successful_Try543@feddit.org 1 week ago
Indeed the regulator, e.g. the Bundesnetzagentur, will knock on your door and inspect your radio and wifi devices. That way, some years ago they’ve found a malefunctioning radio alarm clock in my area.