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Comment by kawfey | Hacker News Reader

"Ideal" isn't doing as much heavy lifting as I thought it would be in this article. This is a basic wardriving setup on flat ground.

Standard wifi is phy limited to ~1600m unless you can increase ack response time limit, otherwise retransmissions will be sent by the sender while ack's are being transmitted by the receiver.

Then, per friis equation, with enough power and antenna gain (it's the antenna gain that really matters) the limit is only obstructions/terrain. Get yourself high enough (mountains, planes, satellites, moons, etc), or bounce of an opportune reflector (planes, moon, aurora, meteors, ionosphere, rain, hail, etc), and there is no real limit, besides how big of an antenna you're willing to build in orbit :P

or just make the throughput really really really REALLY slow and ice your receivers with liquid He.

Hams make a game of it: https://www.arrl.org/files/file/WA50-Standings/Distance-Reco...

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For discussion purposes just "WiFi" isn't doing much. I doubt typical AP<->phone 802.11ac on 5GHz can achieve >1km let alone 802.11ax/be on 6Ghz carrier, even 802.11n can only reach a few hundred meters with line-of-sight, sunny day, and no interference

Long range WiFi is a "solved" problem with 802.11ah with sub-Ghz carrier and can reach more than a km depending on bandwidth requirements

All that assuming tx power is within regulation, no enterprise grade antenna, and all with commercially available parts

I've been running a 1.1km 5Ghz 802.11ac wifi link between two highly directional antennas for three years now. They have line-of-sight, albeit just barely. The kit I got cost $100 at the time. It was quite easy to setup even and supposedly can go much further than I'm using them for.

https://www.amazon.com/dp/B083JRFQ24

With so much benefit we’re getting from wireless connectivity, one hopes that more frequency bands would be opened up, especially in the sub-1GHz range, to enable long distance connections.

And it should be open to public use. Not yet another carrier frequency they will charge us an arm and a leg to use, some of the cell phone connectivity charges are insane, hundreds of dollars for low bandwidth iot sims.

It is immensely frustrating that there is so little unlicensed spectrum available vs the massive amounts of spectrum available to militaries and very rich network operators.

Worse is that the unlicenced spectrum that is available is often so heavily encumbered with restrictions in many parts of the world. Wi-Fi HaLow for example, in ETSI regions, is limited to a paltry 14dBm EIRP in no wider than 2MHz channels and an unacceptably punishing duty cycle restriction in most cases that render it barely able to make a TCP connection (some mitigations exist that involve channel hopping on some products but nothing that works for things that require fixed channels, e.g. IBSS or 802.11s).

> Worse is that the unlicenced spectrum that is available is often so heavily encumbered with restrictions in many parts of the world

It's one of the great things about the UK. As long as you're not causing interference to anyone that's actually paying for a licence, you can pretty much do what you like.

Is it a practical thing as in they won't catch you, or does the law actually say that?

It's not possible to investigate it, and there's no-one to report it to.

Ofcom have about two dozen engineers for the whole of the UK, none of whom are equipped to deal with it.

In general, though, in the UK if you're not making a nuisance of yourself the laws are pretty optional, and this is a pretty good example of it.

The licensed spectrum is not empty. It is scarce because it is fully allocated! Chances are that most of the allocated users are not using it in a given geographical area, so there's space to argue about allocation policies, however.

You can also consider trying to get a license. Costs and probability of success vary widely, but you may as well find out what they are before complaining.

Some European hacker events get temporary licenses to run their walkie talkies and even their own 4/5G cellphone networks. I assume they are cheaper and easier to get than permanent licenses.

In the UK it costs 75 quid for 5 years to licence a pair of 25kHz channels in 68-88MHz, how "sub-1GHz" would you like to go?

I suspect with modern modulation schemes you'd be able to squeeze quite a chunk of bandwidth out of that.

Ubiquiti do 5.8GHz bridges that work well over long distances.

I used a pair to link from my house to a nearby block of flats, around 9km LOS, and back to my friend's house (we didn't have LOS to each other) around 15km.

They worked well at full link speed, around 80Mbps. These were just bog standard off-the-shelf ones, although for space considerations I "mix'n'matched" the links using one with a 10dB dish at one end and the patch antenna at the other.

Here in the UK at least, you can use as high an EIRP as you like, so there's nothing to stop you taking a cheapy USB wifi or bluetooth dongle and 3D printing an adaptor to mount it on the boom of a cheap satellite dish.

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