4 ms·
It's unlicensed worldwide -- free and easy to use. Same as the 900MHz and 5GHz bands. It's a political/regulatory decision, not technical. (And the higher the
by trevyn 9y ago
It's unlicensed worldwide -- free and easy to use. Same as the 900MHz and 5GHz bands. It's a political/regulatory decision, not technical.
(And the higher the frequency, generally the more bandwidth is available, but chipsets are a little more expensive.)
- brianwawok 9y agoThe technical reason is they do not travel through walls that well, so they would make very bad bands for things like radio stations or cell phones.. so why not give it to people to use for local devices.
- dfox 9y agoActually, 900MHz ISM band exists only in ITU Region 2 (ie. Americas), in rest of the world it is usually allocated to GSM and some IIRC aviation related use in the middle of GSM up-down guard band, both are things that you don't want to interfere with, because somebody will care and come after you. 5.8GHz is universally accepted as ISM, but sometimes shared with licensed users (eg. weather radars), who have priority.
- anotherhue 9y agoFun fact: It's available worldwide because they wanted to use Microwaves on ships and planes. https://www.indiegogo.com/projects/why-2-4ghz-chasing-wireless-history https://www.indiegogo.com/projects/why-2-4ghz-chasing-wirele...