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Comment by euduhdhbene | Hacker News Reader

I was recently made aware of WiFi HaLow. Official standard, ranges into the hundreds of meters. Speed suffers at long ranges of course, but still respectable (50-100kbs).

Link: https://en.wikipedia.org/wiki/IEEE_802.11ah

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Difficult within the EU due to ISM limits.

Maybe ok for your garden camera where the authorities just don't care. But no go for any industrial usage.

We have devices sending telemetry and occasional OTA updates without urgency (if it takes a few hours to get it over it’s not a problem).

If you need consistent MB range traffic for cameras I wouldn’t advise it but for low (5kbs) traffic it can be attractive. A few thousand bits can encode quite a bit of information. Don’t be fooled by the “kbs”.

You can do quite a lot with a few MB. Don't tell every React behemoth on the web that we know this trick.

Phew, I looked it up, just by curiosity. What a nightmare :') the rules, regulations, laws are damn strict Oo

Usually this rules are for experts who have to implement the limits. They should not be exposed to end-users.

The problem is that the application of the rules is inherently usage-specific.

For example, with the 1% duty cycle limit it is totally fine to have a transmission take 30 seconds - provided you only send 1 transmission an hour. Want to send one transmission per minute? You'll have to get your transmission time down to 0.6 seconds. And your transmission speed is inherently linked to your data rate, and by extension your signal range.

There's no one-size-fits-all solution possible here. Either the user has to give it some information about their specific use case, or it'll have to stick to the absolute most pessimistic limits.

The ETSI document actually does allow higher duty cycle if the radios take anti-interference measures. Some countries unfortunately have "harmonized" but skipped that part. Theoretically only a dumb transceiver (that can utilize only a single channel) has to limit duty cycle that low in those bands.

The EU's ISM limits are trash.

Really there should be a world wide 900-1000MHz ISM band.

Good luck trying to get the 200 ish countries governments on agreeing.

Kinda explains why starlink router doesn’t integrate it. Would be perfect for cameras around small farms.

Sounds like it fills the same niche as LoRa. Never heard of it though, thanks.

Dead outside the US unfortunately, worse range than regular wifi due to being strangled by lower channel width and ridicolously low power limits. The two bulky HaLowLink routers are the only off the shelf thing with support for it, it's nonexistent as a wifi standard.

I was so excited when I discovered it a few months back after struggling for years to set up reliable wifi for outdoor robotics, only to realize we can't have nice things. The struggle continues.

Lower channel width improves range, at the cost of bandwidth.

No I mean the total frequency range is much smaller. The US has 26 MHz width, while EU/Africa/India only allocated 7 MHz total. The difference in absolute frequency is minimal at ~30 MHz, you almost get more difference from using different channels in the US. What affects range even more is that in the US you can transmit at 1000 mW vs. 25 mW, so the end result is about ~5-10 km vs. 100-200 m. At that range 2.4 GHz is king and stomps it at over four times the allowed power to transfer ridiculously higher amounts of data.

LoRa is not fast enough?

Don’t know about the parent, but I found LoRa adequate for (tiny) payloads (sensor data and such) but OTA updates are a PITA without some alternative channel. Speeds are measured in bytes / sec.

Same channel width and power restrictions. The US' 915MHz band is much much better than the EU 869MHz band

No one is using it in real life. It's a super weak hobbyist protocol with a lot of hype and marketing.

Seriously. Only rich nerds in SAN FRANCISCO are using it.

LoRa has rather iffy security. I certainly would not use it for anything serious.

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