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Comment by the_mitsuhiko | Hacker News Reader

> I don't understand why we haven't more frequency bands available for it

Do we really need more frequency? At this point it does not seem like the challenge for Wifi quality is actually the available frequency spectrum. In fact, I have a lot of devices still in this household that cannot connect to more than 2.4GHz and that is not a question of available spectrum but that supporting all those frequency bands apparently is too costly for some chips on the market.

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Thanks to DFS restrictions in the US, there are effectively only two 80 MHz channels that can reliably be used in the 5GHz band.

2.4GHz only has three non-overlapping 20MHz channels, and those can only do ~286 Mbps throughput in the best case when using 802.11ax.

The 6GHz band is finally allowing 14 non-overlapping 80 MHz channels and 7 160MHz channels, without any DFS restrictions (though some channels are lower-power/indoors only).

In any moderately dense city environment, apartment complexes, or high traffic areas you can absolutely feel the effects of a lack of frequencies.

In American suburbia it might not matter much, but it's definitely an issue for the rest of us

I’m in a dense apartment block in Vienna. The walls are thick enough that I barely see two WiFi’s. Automatic band selection means we end up in different frequencies.

Not everywhere in the world uses the same concrete walls. It's quite common to see dozens of access points trying to share the same three 20MHz channels available at 2.4GHz in places like the US or dense areas in Asia.

I live in the US and I just counted 65 visible APs on 5GHz. The DFS channels aren't usable in this area, so almost all of those are trying to share the same 2 80MHz channels.

I'm in a dense apartment block in a sandstone tenement building in Glasgow. I can see about 30 and most of them are channel hopping permanently. The internet here is absolutely terrible over wifi, i've recently gotten a Wifi 6 router just so I could have very fast wifi in at least one room.

From what I've read a significant contributor to that congestion is routers using too much power. A router in the middle of an 800 ft^2 one bedroom apartment in a dense apartment complex doesn't need anywhere near as much power to cover the whole apartment as does a router at one end of an 2200 ft^2 4 bedroom ranch style house in a suburb.

Out of the box most consumer WiFi routers will be configured for high power and most consumers won't even know that it is something they can change. Even if someone does know about it lowering it will probably make things worse for them unless their neighbors also lower their power.

Maybe consumer WiFi routers should also include some kind of long range low bandwidth communication method, such as LoRa, to find and communicate with surrounding routers to build a map of the routers in a general area (not necessarily a spatial map [1]) and then agree on power levels and channel assignments to avoid interfering.

[1] it would be a map of how they relate by WiFi signal strength rather than how they relate in space. So a two routers that are a couple meters apart but on opposite sides of a wall that nearly completely blocks WiFi radio frequencies would be far apart on the radio map despite being very close together spatially.

It really depends on the materials.

I have one bedroom apartment and the was unstable wifi in one half of it due to L-shaped reinforced concrete wall near the router. Cannot move it due to optic fiber input. To solve the issue I installed second router to have a wifi mesh.

> Even if someone does know about it lowering it will probably make things worse for them unless their neighbors also lower their power.

Ding ding ding! The incentives are all wrong.

Plus, if more SNR is available, you can modulate more bits per unit time, then clear the air sooner.

Most OFDM receivers are EVM-limited though

Perhaps if the bands were wider it would provide sufficient incentive for adoption, since there would be more channels available (and a wider band would presumably be easier than two separate bands that are further apart).

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