"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.
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.
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.
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 be hit with that setup, but I know it can be far enough that LoS due to curvature of the earth becomes a factor.
I do think just getting a wireless P2P bridge is easier and smarter and why this hasn't seen more use.
> 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, and you'll better served by the computer networking infrastructure where encryption is allowed, you can speak to anyone in the world anyway, and the medium (IE physical device) you're using is irrelevant.
Well, ham radio is an EXTREMELY diverse field. I mean, some people are using kilowatts and arrays of yagi antenna to transmit earth-moon-earth. Others are using minimal power (e.g. less than a typical bicycle lamp) to reach someone at the other side of the earth. Some are designing nice sound compression algorithms or algorithms for software designed radio in FPGAs on their self-designed board. Other try to build a full transceiver with less than 40 components total. Some are seeking contacts "rare" countries like other seek rare post stamps.
And most of this isn't really done to communicate. For that, most ham amateurs would use cell-phones, Facebook or whatnot. It's done for the sake of doing it. Or, in other words, to have an excuse to tinker with technical things.
That you can actually communicate is often just a consequence, a by-product. And the "communication" e.g. in contests to seek rare countries is actually really, really bland and boring. Translated to english: "Here is Mike, Calling Reunion, calling Reunion, calling Reunion, Mike here" - "Here is Jaques, Renunion, answering to Mike. I can your you very bad" - "Mike here, to Jaque. I can your you quite nice. And thanks for the talks ... calling Mongolia, calling Mongolia, here is Mike, calling Mongolia ..." --- and it's on PSK31 or CW even shorter.
You see, the ACTUAL communication is boring. The kick is probably to be able to manage and adjust your transceiver, wires, antenna, technical skills to actually be able to connect to these countries.
Or to be able to program and use in-real-life a sound compression algorithm with machine-learning and to test that with alike people on e.g. HF, Meteoscatter, via Satellite (which all produce very different channel characteristics).
Or to produce your own 6-layer PCP with an FPGA that actually does nice SDR algorithms.
There are several legal digital formats (e.g. PSK31, FT8, RTTY) that, while not encrypted, will render 'reading the mail' hard for anyone not aware of those formats and/or the right equipment and where to get it.
Most hams can enjoy the hobby without encryption. The limits discourage uses that endanger the hobby.
I always find the anti-encryption arguments frustrating because all the digital modes are going to have data whitening anyway, and are therefore (if you are not aware of the exact protocol) indistinguishable from encrypted transmissions for all practical purposes. We already have a number of common systems that are basically encrypted because the codecs are proprietary.
The actual mechanism preventing abuse is the requirement to broadcast a callsign in a way that casual observers can interpret it.
Wi-Fi with directional antennas can make long distance links easily.
Just have a look at the European Hamnet network: https://hamnetdb.net/map.cgi - There are a lot of hill-to-hill connections with 60-100km range and plenty of SNR left. Even a few links around 150km.
In professional context these super long links need a very very precise link budget planing to get enough 'nines' in their reliability rating. One of the reasons why you are not seeing them too often.
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.
I’m pretty sure I’ve connected to a bog-standard Mikrotik Metal over a thousand feet. The surprise wasn’t that it connected, it was that the phone could transmit back.
Used a cantenna and a PCI card with modified firmware to great effect when I only had WiFi for internet at the barracks in Japan in the 00's. I was absolutely outside of the legal limits on power, which I didn't really know at the time.
Extreme contention when 250 people had 3 APs as their only connection and half were trying to play WoW at the same time.
We had this ~20 years ago: We created a 3 node network (the center node was also acting as relay) with 4 yagis on rooftops. The distances between the nodes were 1.5 km and 800 m. We used this for around 3-4 years till ADSL became available at our places. Worked flawlessly in clear sky. In heavy rain or snow it was very slow though. We were electrical engineer graduates at that time and built most of it from scratch.
If you are trying to go point to point over a long distance, I would consider something like the unifi air fiber products. They've got a 60ghz model that is basically like a direct optical link. 15km+ no problem.
Not about range, but speed. Wifi is surprisingly slow. I noticed downloading a model from the internet (Huggingface) to my Desktop (connected by LAN cable) is faster than copying it from said Desktop to the laptop in the same room via Wifi.
Yeah. I ran a hand crimped cat-5 Ethernet run to my office and speed tested it, and it turns out my wifi is faster, according to speed.cloudflare.com. Haven't had a chance to debug that yet, but there's a switch and some other wiring in the way.
As a layman, is this supposed to be impressive when any phone can connect to Starlink direct to cell service for messaging, light browsing and even audio?
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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