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Comment by wyxuan | Hacker News Reader

A lot of marketing speak and not much real content. I found this article by Cisco, which seems a lot better at explaining the importance of 6 GHz

https://blogs.cisco.com/enterprise/wi-fis-new-6ghz-spectrum-...

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So to summarize, 6GHz offers a wider frequency range, allowing for more wider channels, and is not used by anything else. As long as WiFi 6 is the only thing using the specific frequency band the AP can assign devices timeslots for both sending and receiving, improving both performance (fewer collisions) and battery life (no need to keep the radio on outside assigned timeslots).

It's also a lot more line of sight, and easier absorbed in concrete and more dense construction materials (think rooms away with layers of wood and drywall).

2.4GHz = 5 in

6GHz = 2 in

The inches are the wavelength height from base to top... Meaning that's pretty much what it can get around without impeded.

Wavelength is not a height, but the distance between between points of the same phase in the variation of the propagating electromagnetic field.

Propagating EM fields are adorned and reflected with multiple effects. Light is electromagnetic fields with a wavelength of ~ 100s nm, yet it can pass through glass, but not a thin sheet of aluminum foil.

> The inches are the wavelength height from base to top... Meaning that's pretty much what it can get around without impeded.

Yeah, that's not what it means.

  λ = c / f

"c" being the speed of light in a vacuum (299,792,458 m/s); wavelength in meters, frequency in hertz -- if memory serves!

(Not sure how I remember that one 25 years after my first ham radio exam but some things just stick in my mind, I guess).

Units don't matter for formulas of quantitites.

For electrical formulas the unit system matters, but not the units.

lambda = c / f

Is true for any combination of units.

Very well, lambda in feet and frequency in nanohertz!

Let's note the "not used by anything else" is probably the most important thing, because of https://ieeexplore.ieee.org/document/1208921

Basically, because WiFi gives an equal opportunity (sort of) of transmission to all devices, old devices or devices far away will slow down the network for fast devices as they will take a big amount of transmission time because of their lower transmission rates.

Greenfield was already a try at "ignoring" old devices but never really took off.

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