[HN Gopher] Ask HN: What's with the DIY state of the art long-ra...
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Ask HN: What's with the DIY state of the art long-range Wi-Fi?
Hey, I lead the technical efforts at one of the charities in
Ukraine; we're now trying to rebuild connectivity for people in
some of the areas where much of the civilian infrastructure was
destroyed and Starlink(r) is not a viable option, or perhaps "not-
to-be easily scaled option." The world of long-range Wi-Fi is a
wild one! We are now trying to evaluate the cost of a point-to-
point mesh network using commodity hardware, and so far have only
experimented with Raspberry hardware to work the antenna, and some
Atheros AR9331-based SoC's. The idea is to make a single device
that can act as both a relay station, as well as an actual hotspot,
it then can be placed in line-of-sight configuration to potentially
cover huge areas (the accepted performance would be anywhere from
0.1-1 Mbit/s point-to-point over anywhere from 5-20km. We are
aiming to bring the cost of such configuration down to $100 per
unit at least. Hopefully, we also wouldn't need to do so and
somebody else could do the whole thing for us at a similar price...
Where would you start, i.e. with the vendors, as well as the
commodity hardware, firmware that should work best for a setup like
this? Bonus points; if it can be somewhat be aware of the current
happenstance. In terms of bleed from Electronic warfare deployed by
the enemy in Ukraine; it has to work hopefully in adversarial
environment! Best regards, Ilya The Stone Cross Foundation
Author : tucnak
Score : 254 points
Date : 2023-01-29 13:02 UTC (9 hours ago)
| cookiengineer wrote:
| First off, use Atheros wifi chipsets because their drivers are
| open source and can be modified.
|
| A cantenna is cheap and can easily bridge around 2-5km if there's
| not much noise on the spectrum.
|
| If you want to create a meshnet, you should look for OpenWRT
| compatible hardware in terms of routers and clients.
|
| There's lots of ralink or RTL based USB wifi dongles that also
| have support for gnuradio so you could also switch frequency
| bandwidths if they got a tuner on them.
|
| An easy and stealthy low-bandwidth meshnet can easily be created
| with old DVB-T usb sticks because the RTLSDR allows flexible
| channel hopping and key rotations, if necessary.
|
| There's also lots of RTLSDR projects that use the LoRa spectrums,
| and they might work if you are looking for a text based
| communications network. That's why I mentioned it. There's also
| the OsmocomBB project which also has support for RTLSDR in case
| you want to create your own DIY GSM network with IMSI catchers
| and the like :)
|
| Wi-Fi usually has the problem that the 2.4Ghz and 5Ghz
| frequencies are overloaded with noise, so they are hard to tweak
| into a long range mesh network.
|
| [1] https://osmocom.org/projects/rtl-sdr/wiki
|
| [2] https://openwrt.org/toh/buyerguide
| EricE wrote:
| Check out the stories section on the Ubiquiti forums:
| https://community.ui.com/stories
|
| Lots of great ideas in there - even if you decide to not use
| their gear. They pioneered repurposing Intels otherwise failed
| wimax for long range links in lue of microwave. The other nice
| thing about Ubiquiti is you get really nice management platforms
| for "free" - included with the cost of the equipment. There is
| much to be said for being able to see all your radios and links
| within a nice, convenient dashboard.
| CraigJPerry wrote:
| >> point-to-point over anywhere from 5-20km
|
| I think 20km point to point is not to be sniffed at if my back of
| a napkin calculations are correct (would love someone more
| knowledgeable to correct!)
|
| Firstly on LOS - that's like 15m+ masts at each end of the link
| (assuming perfect LOS path with no clutter like trees or
| buildings).
|
| Then on free space path loss you'd be looking to overcome around
| 100db+ of path loss i think assuming 2.4ghz ISM band and perfect
| atmospheric conditions.
|
| 10dbi / 12 dbd log periodics for 2.4ghz are available off the
| shelf and are very reasonable to use (not too big, not too much
| wind loading at 15m elevation, weatherproof etc.)
|
| Recieve sensitivity should be around -110dbm maybe? Assuming
| fairly rural conditions so that you're not also dealing with a
| man made noise floor (and also benefitting from a very
| directional antenna to miss most noise too).
|
| You'd need a 1 watt power amplifier minimum, again that's more or
| less off the shelf but there's restrictions globally on use and
| that may make sourcing harder.
| ac29 wrote:
| Just to clarify for people reading this comment:
|
| This:
|
| >10dbi / 12 dbd log periodics for 2.4ghz are available off the
| shelf [I assume this is actually talking about 12dBi and 10dBd
| which are equivalent]
|
| combined with this:
|
| >You'd need a 1 watt power amplifier minimum
|
| Is very illegal in the US and probably most other places in the
| world. There is a hard 1W transmit power limit and a 6dBi
| antenna gain limit. Fixed point to point links can use higher
| gain antennas in combination with lower transmit power, but
| there is no situation in which 1W transmit power + 12dBi gain
| is legal.
| squarefoot wrote:
| They're at war and being constantly bombed; I think being
| legal or not is the least of their concerns.
| madaxe_again wrote:
| The loss is only one facet of the problem - the round trip time
| becomes a significant problem, requiring large windows and
| timeouts and general weirdness - time travelling ARPs, for one
| - as does the ability of consumer equipment to send a signal
| your AP can receive. The Wi-Fi antenna in a phone or laptop is
| not generally very powerful.
|
| The limiting factor isn't the AP, in short.
|
| Now, running LTE microcells - that's a viable option in a
| desperate environment, and one that can be done with SDR. Only
| problem is then getting consumer equipment to authenticate with
| it. This is possible, either with eSims or with cooperation
| from local regulatory authorities - but not altogether trivial.
|
| This is borne off the back of experience - I tried to do long
| range Wi-Fi, but for a usable experience from consumer gear (a
| phone), 2.5km was about as far as I could get with a 1 watt amp
| on a dipole.
|
| Got much further with a yagi, but funkiness emerges beyond
| about 4km on 802.12g. You'd get further on b but your rates
| will be pants.
|
| I would do LTE for this application. My solution where I am is
| a mast that receives LTE atop a hill and has four yagis doing
| 802.11g to receiver nodes, which each comprise a repeater with
| a yagi pointed at the mast, and a dipole omni to get a solid
| 500m radius around each repeater. I've covered 15ha of tortured
| terrain with Wi-Fi with this - and come to think of it, the
| highly directional signals could provide hardness against
| interference and would greatly mitigate interception issues.
|
| Oh, and I'd you're doing yagis, you need real ones, not the
| fake crap you'll usually find for sale. The real deal is about
| 70cm long for 2.4ghz and will have tapered vanes to the point.
| Commercial models come in a plastic can.
| namibj wrote:
| Freifunk should work fairly easily; take 2-3 2X2 MIMO routers
| (like 20 bucks each), adjust the firmware for them, get the P2P
| directional link to either use existing satellite dishes (not
| sure what the easy orthomode splitter is, here, as you need same-
| source-spot signals for both horizontal/vertical or left/right
| polarization), or simple DIY'd axial helix antennas (made on
| plastic/cardboard tube of appropriate diameter, by winding an
| even spiral at the right "thread pitch", then fixing it in place
| with glue/tape, and weatherproofing the assembly) (one wound like
| a normal screw thread, the other like a reverse thread, and put
| side-by-side with a gap of like 5-10 tube diameters to not
| interfere with each other).
|
| Use the router's switch ports to connect them with each other,
| and use one local router with stock antennas pointing straight up
| to serve local clients and mesh with possible nearby mesh nodes.
|
| The electronic warfare resilience is going to involve hacking the
| collision avoidance techniques to be sufficiently less
| aggressive, and likely to get Freifunk to use encryption for the
| mesh links. If necessary, just set up P2P links with per-link
| encryption. Routing-table-affecting nodes in a mesh sadly need
| some inherent trust to be performant in the non-adversarial case,
| or at least, no one seems to have tackled that possible issue yet
| (to the point where you could just compile existing software for
| the router at hand and get something working by the end of next
| week).
| MayeulC wrote:
| What do you think of Yggdrasil to handle mesh routing? I know
| it has "flapping" issues (connecting and disconnecting the root
| node rapidly), though that was somewhat mitigated, and need to
| control the root (compute/"mine" a suitable key) first.
|
| Ideally, we'd have Wi-Fi NAN (Wi-Fi Aware/Neighbour Awareness
| Network) on all devices (including routers, smartphones),
| discovering devices close by and allowing Yggdrasil to work on
| top. That's very recent though. I blame Apple keeping AWDL
| proprietary.
|
| Some of that can probably be approached by connecting handsets
| to multiple networks at once (the chips usually support it, but
| I don't know about the OS).
|
| In the end, in this case it's probably better to ask a local
| ISP for cooperation (ask for a part of their spectrum, and put
| 4G antennaes and local 4G to Wi-Fi APs). It can still be meshed
| together.
| jacquesm wrote:
| Seconded, Freifunk is easy to use and pretty resilient, there
| is also a pretty large community of people with knowledge about
| it and the hardware requirements are as low as they will go.
|
| Beware of some of the possible downsides: the default is for
| Freifunk nodes to be placed on a map and I'm not sure if this
| is a requirement or not but it might provide easy targeting
| information for the Russians. This will have to be taken into
| account, and if possible to be done without.
|
| Also, Freifunk nodes are open enough that behind-the-lines
| enemy could use it to phone home without a trace, so likely
| you'll need some extra FOF kind of authentication mechanism.
|
| People more versed at this than I am will most likely have a
| whole bunch of other concerns about setting up a system like
| this.
|
| Finally, long haul is all about antenna tech, I would suggest
| to enlist the help of as many local HAMs as you can find.
| ajb wrote:
| While being placed on a map is clearly bad, commodity WiFi is
| not great for anything that shouldn't be located, as it is
| obviously radiating in RF and will be detectable some
| distance further than the signal can actually be decoded.
|
| Tactical radios are specially designed for the problem. Eg
| using spread spectrum approaches, and plain not transmitting
| most of the time and only by the choice of the operator.
|
| It's possible that open source SDR could be applied, but I
| guess that the Ukrainian side have been supplied with
| military radios by their allies.
| mNovak wrote:
| I'm not very familiar with Freifunk, but if it interfaces
| like a normal WLAN to the user, then simply not advertising
| SSID and a basic password will go pretty far. This is
| obviously not secure against any sort of special operative,
| but eliminates it as a very easy convenient tool for e.g. a
| mobik with a cell phone, if this finds its way anywhere near
| a frontline.
|
| An upside of highly directive, P2P links is that they can
| provide some protection against EW, simply by nature of
| having a constrained field of view. Also I'll note most
| consumer devices (laptops, cell phones) have pretty bad
| antennas, they're assuming you have a router right nearby.
| You might get much better coverage if you're also able to
| provide the user with a simple USB dongle that can attach to
| an external antenna (e.g. a 10dBi yagi-uda)
|
| If there is need for any input on the antennas side, I'm more
| than happy to help (EM PhD, design antennas for a living).
| 2.4GHz is relatively forgiving, you can literally hand make
| antennas, with some attention to detail. If you have access
| to shipping (I really don't know the situation) they can be
| mass produced on PCB.
| armagon wrote:
| Take a look at AREDN, the Amateur Radio Emergency Digital Network
| -- https://www.arednmesh.org. They use commercial WiFi gear (see
| https://www.arednmesh.org/content/supported-platform-matrix) with
| custom firmware, running on the adjacent ham radio bands (which
| have less noise on them, allowing for greater distance, although
| I wouldn't be surprised if the WiFi bands and radio bands have
| different allocations in Europe.) Surprisingly (to me, anyway)
| they say that 'N' speed WiFi works better at long ranges than
| newer protocols.
|
| Honestly, as you are in Europe, you should look into the European
| Hamnet. See https://hamnet.eu/site/community.html and
| https://www.tapr.org/pdf/DCC2014-TheEuropeanHAMNET-DG8NGN.pd....
| They aren't using WiFi, but the goal is the same.
|
| Both of these require licensed amateur radio operators to use
| normally. (Maybe wartime is a different matter). I do believe I
| heard that Russia took radio transceivers away from operators in
| the Ukraine, but don't know much about it.
| mzerod wrote:
| My time to shine- this is for anyone concerned about ham
| operation in Ukraine
|
| https://eindhoven.space/2022/10/08/ham-radio-usage-in-ukrain...
| pantalaimon wrote:
| > the accepted performance would be anywhere from 0.1-1 Mbit/s
| point-to-point over anywhere from 5-20km
|
| Sounds like WiFi HaLow could be an option here
|
| https://www.cnx-software.com/2021/12/21/wifi-halow-gateway-k...
| superkuh wrote:
| The state of the art for any non-ionospheric relatively high
| frequency radio transmission is how high the antenna pair are
| above their local terrain. Power input, modulation, antenna type,
| these hardly matter in the face of a hill or a valley.
|
| The _only_ thing that matters for 2.4 /5 GHz wifi long range is
| height above surrounding terrain to get line of sight. The
| highest technology is literally the technology to get the
| antennas highest; ie poles, towers, tops of tall buildings,
| actively lifted (and powered) drone platforms for antennas, sides
| of mountains, etc.
| MayeulC wrote:
| Can't antenna gain help a lot as well? Parabolic dishes, etc.
| noodlesUK wrote:
| I think in terms of cheap PtP and PtMP equipment that has fairly
| long ranges you can't beat ubiquiti's product line. They are
| fairly easy to use for technical people with less networking
| experience. Try out their cool network planning tools at
|
| https://ispdesign.ui.com/
|
| (I have no affiliation with UBNT, I just use their stuff at home)
| bschne wrote:
| We started using their stuff "as an experiment" in my civil
| protection service unit and have had great experiences so far
| -- a breeze to set up and manage, really good performance, and
| surprisingly affordable even at retail prices. I think it's a
| bit above your budget constraint except for the CPE side, but
| maybe you can reach out and set something up given it's for
| humanitarian purposes or someone on here has a connection.
| simne wrote:
| Wi-Fi is not good solution, because too prone to noise. Better if
| find something frequency-hopping.
|
| BTW I'm in Kiev, first time hear about The Stone Cross
| Foundation. Could You tell more about it?
| tucnak wrote:
| Hey, we've ultimately decided to separate the local hotspot
| (Wi-Fi) and the actual long-distance antenna, as well as a HSM
| using a dedicated controller. Unfortunately, there's still too
| many moving pieces and customisability presents a huge
| challenge. (For one: we need to introduce Diffie-Hellman key
| derivation, basically to figure out the hopping pattern in the
| frequency domain.) However, in some cases it may be beneficial
| to have the Wi-Fi endpoint cover a bigger area, then it's race
| to the bottom to allow for the receiver hardware. The Stone
| Cross Foundation is the first Ukrainian charity built
| completely around zero trust and data analysis, we specialise
| primarily in humanitarian logistics, warehousing, Diia
| integration, and superforecasting. Our biggest contribution is
| a back-office solution for volunteer network management which
| includes Matrix-CRDT and other Double Ratchet tricks. We have
| struggled to go retail, and at some point gave up for the time
| being in favour of concrete priority engineering projects at
| hand.
|
| Happy to get in touch and tell all!
| https://keys.openpgp.org/search?q=ilya%40hrest.org
| capableweb wrote:
| Reach out to various existing infrastructure projects that build
| and maintain large community-owned P2P WiFi deployments, the two
| largest ones are Freifunk and Guifi. They would surely be able to
| and wanting to help you, if you reach out to them. Try
| https://freifunk.net/en/contact/ and https://matrix.guifi.net/
|
| Most of them are using commodity hardware from Mikrotik,
| Teltonika and Ubiquiti. Basic setup for a personal node is just
| an antenna + router. Then they usually have the concept of
| "supernodes" who are responsible for hooking up multiple personal
| nodes, and have uni-directional antennas + multiple ones + bigger
| routers to facilitate the routing.
|
| I'm not sure you'll be able to put together a supernode with
| decent range for under $100 though, think the cost would be more
| than that, but I would be happy to be proven wrong.
|
| In terms of firmware, I've almost exclusively seen OpenWRT being
| used (and the rest running default Mikrotik/Ubiquiti firmware),
| with various self-made patches done to it before installing it on
| the hardware.
| wifitawy wrote:
| This is the right answer. The Freifunk people have a lot of
| experience and knowledge.
|
| Anecdote: A while back I was moving houses ~1km with trees
| obstructing line-of-sight and without connectivity at the new
| house for the first couple of months. I had to move but could
| keep the old place connected. I jerry-rigged Ubiqity PtPs that
| I had inherited from a friend at each end. Packets started
| dropping on rainy days but it was working surprisingly well.
|
| Not necessarily a fan of Ubiquity and their closed ecosystem
| per se, and it might not be the best pick for a project like
| OPs if there are options.
|
| (Throwaway because these hotspots were brought from abroad..)
| hoppla wrote:
| A curiousity about Ubiquiti firmware. It seems like the AP
| firmware is based on openwrt
| MayeulC wrote:
| And IIRC a lot can be flashed with openwrt too!
| jk_i_am_a_robot wrote:
| Why not just use off-the-shelf equipment with modified external
| antennas? Use OpenWRT on cheap equipment that will accept an
| external antenna.
| jokoon wrote:
| Seems pointless, to me long range wifi is 4g or 5g.
|
| I'd rather have a way to do long range data directly between two
| phones.
| vogon_laureate wrote:
| Have you looked into the Ubiquiti AirMax kit?
| senectus1 wrote:
| Ubiquiti is amazing. really attractive price point, pretty
| solid kit and performance and really easy to setup and use.
| capableweb wrote:
| Compared to Mikrotik, Ubiquiti only has better UI and more
| bells and whistles (pretty graphs and so on), while Mikrotik
| tends to be cheaper and have the same performance and being
| able to control/configure every aspect of the hardware. If
| you're trying to build a cheaper kit, I'll probably go for
| Mikrotik, in this scenario at least (ie not "WiFi in my
| house/property" but cross-country mesh network).
| tiagod wrote:
| Agreed. I've got a bunch of their switch gear and have
| setup WiFi too with no issues. Got a 4G LHG dish setup in a
| roof for 2 years too which works great (there's pretty much
| no cell service there with a phone, the dish reaches max bw
| of the (admittedly slow) closest tower.
| ajot wrote:
| It's not state of the art (and it's showing it's age) but I've
| always loved the Wireless Networks in the Developing World book
| [0]. It covers the basics about propagation, antennas,
| infrastructure and such, but software has changed a bit since
| last edition.
|
| Also, keep an eye on different editions, as I believe last one is
| a little less tech focused and more into how to run a community
| project, both sets of knowledge are highly important but second
| edition might be outdated in regards to software availability in
| OpenWRT and Linux in general.
|
| https://wndw.net/book.html
| fIREpOK wrote:
| For emergency communications (probably lower than 0.1/1mbps at
| 5/20km though), you might be able to get away with a LoRA..
| Probably would be a lot cheaper to build and lighter to carry
| around (all with a smaller antenna).
| capableweb wrote:
| LoRa would indeed allow cheaper and more lightweight
| installations, but the bandwidth comparison between WiFi and
| LoRa makes LoRa basically not a comparison, unless you want to
| build something text-only over it. Forget being able to browse
| the web for example (besides HN probably).
|
| Edit: I see now you mention the bandwidth difference and saying
| to use LoRa just for emergency broadcasts, that'd make sense.
| squarefoot wrote:
| A few random ideas:
|
| For short range coverage you may want to consider repurposing
| commercial hardware (routers, access points etc) that supports
| OpenWRT, those should be easier to find, also used, and way
| cheaper than specialized hardware. https://openwrt.org/toh/start
|
| Long range communications will require directional antennas,
| which implies mostly fixed and point to point. Also to achieve
| line of sight and avoid the fresnel zone obstruction the antennas
| need to be mounted higher than the highest obstacle in between.
| Solar power is viable, but battery backup should also be
| provided. Antenna masts and solar panels would make them visible
| from distance, and of course although the traffic can be
| encrypted, they scream all around the air that there is a station
| operating there; hidden SSID does _not_ make their operation
| invisible to a spectrum analyzer or any specialized electronic
| warfare gear - of which the enemy has plenty - that should be
| taken into consideration.
|
| Anyway, Mikrotik makes some interesting powerful wireless routers
| like the Metal 52 ac which can operate at over 1W both on 2.4GHz
| and 5GHz. They're conveniently bullet-shaped and can be supplied
| by PoE, so that you can connect them just behind the antenna
| (either directional or omni) to achieve minimum losses. I've
| bought some good WiFi hardware, cables and antennas at netek.eu
| (now wifimarket.eu) and batna24.com. Mikrotik is Latvian, Batna
| and Wifimarket are in Poland, you shouldn't have problems
| shopping from them. Wifimarket today seems to have a very reduced
| product line compared to a few years ago when I shopped there.
| They had really good antennas and cheap really good quality parts
| to build antennas (dipoles to make patch antennas by adding a
| reflector etc.) that would come very handy on the field. You may
| ask them if they still sell them elsewhere. (btw. no affiliation
| here, just a happy customer)
|
| Think about using fiber optics at least for longer fixed paths: a
| couple routers with SFP can provide a gigabit connection over
| several kilometers, and the fiber cable can be easily buried so
| that it's not easy to notice and doesn't hint the enemy that a
| transmitter is operating nearby like WiFi would certainly do.
|
| For very slow and long distance communication, namely text
| messages, LoRa can be an option to which encryption can be added
| externally. All other considerations about radio transmission
| remain valid for LoRa too, however. You may find these links
| interesting:
|
| https://disaster.radio/ https://meshtastic.org/
|
| Also worth of mentioning for different purposes:
| https://github.com/ExpressLRS/ExpressLRS
|
| Best luck with everything. slava ukrayini!
| prpl wrote:
| A project I worked on did 802.11(b)? over about 30+ kilometers.
| The wireless stack was custom written though. The closer devices
| had planar directional antennas. The further devices had
| parabolic antennas. There was 3 different towers servicing ~180
| detectors. Planar antennas near other towers had to have a shield
| added. This was 2007.
|
| I don't recall bitrates. The area was well over 500 km^2
|
| project is here: telescopearray.org
| rcarmo wrote:
| The Pi is lousy for that unless you get something with an
| external antenna connector. Back in the 2000s, we set up inter-
| building links with Cisco Aironet PCMCIA cards (which did not
| have the EIRP power limits currently enforced for consumer
| products) at blistering 11Mbps speeds (well, it was fast for the
| time) and a few years later we did it again at 54Mbps in the
| 2.4GHz band with OpenWRT devices like the WRT54g, doing 10Km with
| external directional antennae.
|
| I also built my own 3G range extender with an almost identical
| off-the-shelf $50 Yagi antenna at a country cottage (2.2 and
| 2.4GHz are close enough for an antenna to carry both), so I've
| spent a while pondering those kinds of scenarios.
|
| But addressing your points directly, I would look for OpenWRT-
| compatible devices with external antenna ports and the ability to
| do both 2.4 and 5GHz - and most likely try to use 2.4 for long-
| distance point-to-point links with Yagi antennas.
|
| Hitting the bitrates you mention seems perfectly doable, although
| I must point out that the antennas are conspicuous (about the
| length of two Pringles cans). The challenge I found is having
| router hardware that can pin SSIDs to separate radios, because
| most of the modern stuff aims for diversity and prioritizes
| throughput.
| canucker2016 wrote:
| Has the Raspberry Pi supply problem ended in Europe/Ukraine?
|
| According to https://www.tomshardware.com/news/raspberry-pi-
| adds-100000-u..., second half of 2023 is when RasPi supply
| should be restored to pre-pandemic levels.
| larrydag wrote:
| Here is a write-up of the NYC mesh network
|
| https://docs.nycmesh.net/intro/
| capableweb wrote:
| NYC Mesh is a great initiative, and probably the one with the
| most "modern" setup as it's the newest one. But take into
| consideration that it might also not be as reliable or work at
| the same scale as Freifunk or Guifi.
|
| Number of online nodes per network as of today:
|
| - NYC Mesh: 1281 (https://www.nycmesh.net/map)
|
| - Freifunk: 42,524 (https://www.freifunk-karte.de/)
|
| - Guifi: 37,721 (https://guifi.net/en/node/3671/view/nodes)
| blablabla123 wrote:
| Not sure if these numbers are the best to go by. Freifunk
| surely has the most setups. I might be completely wrong on
| this but I think most Freifunk installations are isolated,
| i.e. single-node with e.g. the local DSL as upstream. I
| wonder which of these have nodes with no cable-bound upstream
| or at least actually _used_ interconnects with other nodes.
| yobbo wrote:
| Mikrotik makes wifi radio-links where the radio is integrated
| into the dish, connected by cat5 for example. The right solution
| to avoid lossy antenna cables/connectors where power is limited
| to begin with.
|
| For long distances, you will probably need to "scavenge" bigger
| dishes (1m diameter) from other sources to be within budget.
| IIRC, any microwave dish will be useable, including satellite tv
| dishes, if you use a suitable transceiver-antenna "head" (DIY-
| able) and align it. In addition, tv dishes on buildings look
| inconspicuous.
|
| Ideally, the wifi radio should be placed in the focal point of
| the dish and directed such that the reflected signal points to
| the horizon. But most TV dishes are not symmetric to allow them
| to be mounted vertically (and avoid collecting snow) while
| pointing into the sky.
|
| You might need to read up and figure all this out.
| olouv wrote:
| One tool you could use to design the network, check line of
| sight, potential bandwidth, etc. is this nice Ubiquiti tool:
| https://ispdesign.ui.com
| DicIfTEx wrote:
| I can't talk to long-range Wi-Fi or necessarily the state of the
| art, but perhaps a couple of these resources may be helpful:
|
| The Internet Society have some resources on community networks
| here: https://www.internetsociety.org/action-
| plan/2022/community-n...
|
| And then there's the Things Network, which operates over the
| LoRaWAN (Long Range Wide Area Network) protocol:
| https://www.thethingsnetwork.org/
|
| Lastly (and potentially not super relevant), there was a talk at
| LibrePlanet 2021 about efforts to set up community networks in
| Turkey (although more from the perspective of ensuring user
| freedom): https://media.libreplanet.org/u/libreplanet/m/freeing-
| networ...
| jonah wrote:
| I just found out about a mesh wisp in northern California. I
| don't know anything about their tech stack but they claim to be
| all open source and might be something worth digging into.
|
| https://furtherreach.net
|
| http://www.denovogroup.org
|
| http://www.airjaldi.org
|
| https://www.linkedin.com/in/yahel
|
| https://github.com/yahel
| slackfan wrote:
| Heyo. I run a small rural ISP using off-the-shelf Mikrotik P2P
| hardware. Cost per AP is about 80 dollars a unit for 100mb bi-
| directional link that hits out on average 16km, depending on your
| LOS.
| mikewarot wrote:
| It sounds like you're going to be experimenting with high gain
| antennas connected to whatever nodes you use.
|
| Slot antennas are something flat and high-gain which might be
| easiest to deploy, once you get constructing them figured out.
|
| https://en.wikipedia.org/wiki/Slot_antenna
|
| http://www.trevormarshall.com/waveguides.htm
| efxhoy wrote:
| I did long range (50km) radio links in the Swedish army 10 years
| ago. If you want to have the best possible impact I suggest you
| work with existing telecom companies and ISPs. They have the
| knowledge and the resources. Nothing you can hack together is
| going to beat commercial radio links mounted in actual towers and
| regular phone transmitters.
| emperor_ wrote:
| Wireless Belgium has been building DIY wifi networks on a very
| large scale since 2003. They have a lot of experience and maybe
| even spare hardware to start with your project. To get in touch:
| https://www.wirelessbelgie.be/contact/
| spiritplumber wrote:
| https://f3.to/cellsol/ We make these, but the bandwidth is crappy
| - it's more for a pager or an emergency message service.
| verdverm wrote:
| There is HamWAN (https://hamwan.org/) that works over amateur
| radio frequencies. Seems like a very DIY, volunteer, and helpful
| community
| minhmeoke wrote:
| If you are using Linux-based infrastructure, this list contains
| some recommended Wifi chipsets. https://github.com/morrownr/USB-
| WiFi/blob/main/home/The_Shor... In particular, ALFA AWUS036ACHM
| has a combination of long range and low cost (~$39 USD).
|
| Ubiquity UAP AC LR also has long-range access points with up to
| 183 meters range for ~$109 USD:
| https://store.ui.com/products/unifi-ac-lr
|
| If you are more ambitious, you can deploy an OpenWRT BATMAN-based
| mesh network: https://openwrt.org/docs/guide-
| user/network/wifi/mesh/batman
|
| I recommend using something that supports OpenWRT out of the box,
| such as GL-iNet Mango Mini Router GL-MT300N-V2 (~$20 USD
| refurbished) https://openwrt.org/toh/gl.inet/gl-mt300n_v2
| https://store.gl-inet.com/products/certified-refurbished-pro...
|
| Please only use this information for humanitarian/civilian
| purposes and not for military objectives. Thank you!
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