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Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

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Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#41

Post by ErroneousBosh »

BetterThanSober wrote: post #18
kawfey wrote: post #15

"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…

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…

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.

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#42

Post by ErroneousBosh »

itopaloglu83 wrote: post #30
pseudosavant wrote: post #29

Earlier quoted context omitted.

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.

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.

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#44

Post by ErroneousBosh »

neilalexander wrote: post #38
itopaloglu83 wrote: post #30

Earlier quoted context omitted.

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…

> 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.

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#45

Post by ErroneousBosh »

DaSHacka wrote: post #20
CobaltFire wrote: post #4

They address that they were looking at the maximum unlicensed power. In HAM circles some people do use WiFi in an arguably legal manner by making the SSID their callsign and either making the network open or putting the password somewhere public. This is because you are not allowed to use public bands for encrypted communications (with a carveout for satellite control, for obvious reasons). I'm unsure what ranges can…

> In HAM circles some people do use WiFi in an arguably legal manner by making the SSID their callsign and either making the network open or putting the password somewhere public. And presumably also no SSL when browsing? Part of why I never really understood the appeal to getting a ham license. Things like no encrypted communications really limits the utility. Anything outside of talking to randoms on the open air,…

> Things like no encrypted communications really limits the utility.

How so?

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#46

Post by simoncion »

holgerschurig wrote: post #26
somat wrote: post #9

I vaguely remember some sort of stunt where they had got hold of two 3 meter dishes paired them with off the shelf wifi radios, mounted one on a pickup truck and drove out across a dry lake bed. 53 miles before signal loss is what I remember. I will probably never be able to find the source, and my poor memory probably inflated the range like any good fish story.

This are however just records. E.g. "I still have a connection". These records aren't really usable in real-life, e.g. to view a movie. When it rains, or is foggy. Just mounting a maneuvering 3 m dish to your laptop isn't everyones most desired leisure ...

> This are however just records. E.g. "I still have a connection".

This chatter about a successful 2005 Defcon shootout [0] indicates that a 125 mile link was able to pass traffic sufficiently reliably to be used for SSH, VNC, and other applications summarized as "etc" for several hours.

The one that somat appears to be thinking about was the year before and set up a ~55 mile link. The Wired article about it [1] doesn't say much about what data was shoved over the link, just that they "...shot a signal from one station to the second station with an encrypted message provided by the judges.", suggesting that at least some data transfer was required to consider the attempt valid.

> Just mounting a maneuvering 3 m dish to your laptop isn't everyones most desired leisure ...

That would have to be a very fancy dish to handle targeting a spot 1.5Km+ away while attached to a device that's being manhandled. I imagine it'd make much more sense to put the dish on a fixed mount and wire it up to the laptop, run wired ethernet from the AP to the laptop, or have a second radio in an AP to provide service to nearby clients.

[0] https://groups.google.com/g/SOCALWUG/c/5T5wekafdv8>

[1] https://defcon.org/html/links/dc_press/archives/12/wired_wif...>

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#47

Post by pantalaimon »

ck2 wrote: post #39

aren't devices in north-america also allowed 1 watt on 900mhz? I wonder how far that can go I think I have an ancient wireless phone on 900mhz and all my weather sensors are on 900mhz https://www.digikey.com/en/articles/unlicensed-915-mhz-band-...

There is IEEE 802.11ah that operates on that band, you can reach up to 1 km

https://www.cnx-software.com/2026/01/13/halowlink-2-wi-fi-ha...

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#48

Post by kooi »

Used to work at an evtol company and we used a plain ol router connected to a huge PoE antenna to connect to the vehicle which had some plain ol usb wifi antenna.

It was TCP/IP data streaming down and commands going up.

Demi-automonous testing at some 2km range. Worked great...

XD

Re: Long Range Wi-Fi – Pushing 2.4 GHz Wi-Fi to the limits (2019)

#49

Post by zajio1am »

When we started wireless ISP in in early 200x, it was common to run 2.4 GHz links with 5+ km distance, having 24 dB antennas on each side. with the basic 17 dBm radio one was 20 dB over EIRP limit...

Here in Czechia, there was also another unlicensed band, 10.5 GHz, that has more sensible regulation - instead of EIRP limit, there was PA limit (power before antenna). So one can do long-range links with large enough antennas and most long range links was later converted to these. Unfortunately as this is local unlicensed band, radios for that were orders of magnitude pricier than generic wifi.

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