Remote internet via SDR

[Free_WiFi]

Why there's no protocols wich could allow us to use the SDR tecnology for remote internet connection?
I didn't know how to explain what i really mean(because of my low english skills)
however my idea and question at the same time is:
why the sdr radio can't be used like an reapetitor for remote internet connection?

[Free_WiFi]

For example:
with this kind of tecnology(+ an directional dish antenna),we could be able to share our internet with people from far away like 200km's.
This is 1 kind of example.

[ElectronicCat]

I'm not exactly sure what you mean. With a sufficiently powerful SDR and a lot of DSP you could get 802.11ac WiFi working on an SDR if you wished.

What I suspect you mean is why are there no protocols which can be easily implemented in low cost SDRs. And the answer is that I suppose is that it would serve little purpose standardising for something which isn't best suited for the application. WiFi and other RF transceivers are cheap and commonly used for the type of range extension and last-mile connectivity you're describing. You could always come up with your own PHY and MAC layers to be implemented on an SDR if you wished, and then transmit data to and from the internet by implementing IP and above layers, however the data rates will likely be abysmal and the cost of your SDR solution will be more than a commercial microwave transceiver for probably lower power and sensitivity.

[Free_WiFi]

I'm not exactly sure what you mean. With a sufficiently powerful SDR and a lot of DSP you could get 802.11ac WiFi working on an SDR if you wished.

What I suspect you mean is why are there no protocols which can be easily implemented in low cost SDRs. And the answer is that I suppose is that it would serve little purpose standardising for something which isn't best suited for the application. WiFi and other RF transceivers are cheap and commonly used for the type of range extension and last-mile connectivity you're describing. You could always come up with your own PHY and MAC layers to be implemented on an SDR if you wished, and then transmit data to and from the internet by implementing IP and above layers, however the data rates will likely be abysmal and the cost of your SDR solution will be more than a commercial microwave transceiver for probably lower power and sensitivity.

Ooh seems like the sdr tecnology is not that limitless as I thought before.
.

[ElectronicCat]

Ooh seems like the sdr tecnology is not that limitless as I thought before.
.

SDR is great for research, working with unknown protocols and such but for high volume fixed installations you can't beat dedicated hardware for the task.

[OwO]

Don't overestimate the efficiency of wi-fi. If you look at sensitivity specs of any off-the-shelf wi-fi hardware it is over 20-30dB from channel capacity limits, and far worse at the lower bit rates. Even the AX5043 can get within 13dB of the Shannon limit. 7dB of that is due to the weak FEC, 3dB due to noise figure, and remaining 3dB is due to the use of FSK. How wi-fi hardware manages to fuck it up even with a strong FEC and QPSK/BPSK is beyond me, but it doesn't surprise me because wi-fi hardware are designed for indoor use where performance is interference limited and not noise figure limited. I don't think it's hard to beat wi-fi at all for long range data links, if you implement your modem properly and don't skimp on RF design in your SDR (e.g. SAW filters, LNA, high linearity signal path, etc).

[OwO]

The other thing to consider is that the 802.11 protocol is absolute shite for anything other than indoor smartphone/laptop use. The high protocol overhead means it's unusable at the lower bitrates, the listen-before-talk means you are unable to transmit anything as soon as you have unexpected environment noise, and the packet radio modem means you waste significant time transmitting preambles, while a long preamble IS necessary to get reliable lock at low SNR.

The solution of course is a continuous streaming OFDM transmission, not unlike LTE, where the base station transmitter is always on so that the other end can maintain lock. Do away with listen-before-talk and have the other end explicitly communicate channel quality of each OFDM subcarrier, then you can shut down subcarriers that get significant interference. Finally the stations must be full duplex (separate bands for transmissions going each direction) beause you have to maintain continuous transmission on both ends. And of course, do away with all the handshaking/association parts of 802.11 because you want a permanent link.

[extide]

To get decent speed you will want an SDR with a wide bandwidth. The Lime Mini and Lime SDR are the best ones that are reasonably affordable that I am aware of, the Lime Mini is about $159 and has 30.72Mhz of RF b/w, while it's bigger brother the Lime SDR can do 61.44Mhz for $299. I really want to get one of them to play with at some point. I mean, to actually make a link work reliably this is going to be pretty complex and if you actually want something usable across 200km I would suggest looking at the Ubiquity Air Fiber or Air Max products as that is probably the cheapest/fastest off the shelf stuff you can get.

[0culus]

I just saw something the other day about a guy who needed a 2 mile link to a rural house, so he rigged up a wifi router with a high gain Yagi and claimed he was getting 7 Mbps down...

[Lord of nothing]

Why there's no protocols wich could allow us to use the SDR tecnology for remote internet connection?

Use 2 CB Radio with Packed Radio Links. 
And pls dont argue about the speed.

[wraper]

I just saw something the other day about a guy who needed a 2 mile link to a rural house, so he rigged up a wifi router with a high gain Yagi and claimed he was getting 7 Mbps down...

Actually it's not a so good result. You could do better, especially in rural area. All you need is unobstructed path between highly directional antennas.

[Lord of nothing]

Here in Austria are certain Freq for Directional Radio communication.
There was a Page how does the Austrian Military use a Network of Dish and Reflector for that.

[radiolistener]

The best way to get remote internet is optical fiber.
It gives you incredible speed and no need to fight with interference and noise issues.
Optical fiber is much-much faster than any radio-link and even any wired network.

Also you can build your own DIY gigabit data-link with infrared lasers:
https://hackaday.com/2016/03/10/gigabit-ethernet-through-the-air/

[Lord of nothing]

The best way to get remote internet is optical fiber.

Sure if everything is on your own property. If not you are screwed up. If it run over Public Ground good look to get a Permission. 

Also you can build your own DIY gigabit data-link with infrared lasers:

until a Bird cross. Laser are not that legal in many ways. The dont have to interferer with Aviation (that include Heli). In my Area from Time to Time a Rescue Heli land so the could not get blindet by that.

[radiolistener]

[radiolistener]

If it run over Public Ground good look to get a Permission. 

if you want to use radio-link (SDR based or any other kind of technology), you will need to get Permission even for communication on your private ground
And I'm afraid it will cost you much more and license will be much more complicated, than a small optical fiber through public ground.

[Lord of nothing]

Depend when I stay with the 1W on 5Ghz Wifi I can do what every I want. 
If you use other Band or what ever you need a Permission and here in Austria the arent that cheap.

[radiolistener]

Depend when I stay with the 1W on 5Ghz Wifi I can do what every I want. 

this is because this band is already licensed for WiFi and you're granted permission to use certified WiFi equipment for such bands. But you cannot use it for other purposes than WiFi

I'm sure that low power IR laser communication will be much more easy and give you much less headache.

[Bicurico]

SDR is just a software replication of radio hardware.
Why would you want to use SDR for wireless internet if there is already WIFI/WLAN with hardware implementation?

Also, amateur radio communication may NOT be used for encrypted and/or commercial communication! This rules out relaying internet access to any amateur radio frequency.

[radiolistener]

Why would you want to use SDR for wireless internet if there is already WIFI/WLAN with hardware implementation?

And I think almost any WiFi/WLAN already uses SDR technology internally
Because SDR technology come to amateur radio from commercial communications, such as GSM/CDMA and other kind of digital radio-link communications, where SDR is already used for a long time.

[Lord of nothing]

https://www.ui.com/airfiber/airfiber5/

I'm sure that low power IR laser communication will be much more easy and give you much less headache.

Sure but the must be very directional. Do you ever use that in a practise?

Also, amateur radio communication may NOT be used for encrypted

When I transmitt just Numbers are the Encerypt or not? (aka Number Station).

Thats why I still recommend still CB Radio here in Europe.
https://en.wikipedia.org/wiki/Packet_radio

Military Techniqe was one of the first user of SDR Stuff.
When my Fiber Connection @Home work I will turn the CB Radio back on and Transmitt 24/7 stuff. 

[wraper]

The best way to get remote internet is optical fiber.
It gives you incredible speed and no need to fight with interference and noise issues.
Optical fiber is much-much faster than any radio-link and even any wired network.

I would like to see how you would install a few km of optical fiber, especially not in your property.

Also you can build your own DIY gigabit data-link with infrared lasers:
https://hackaday.com/2016/03/10/gigabit-ethernet-through-the-air/

Try that outdoors over a few km. Even if ignoring rain, fog and birds, long term positioning would be a big trouble on it's own.

[extide]

this is because this band is already licensed for WiFi and you're granted permission to use certified WiFi equipment for such bands. But you cannot use it for other purposes than WiFi

No it's an ISM band which means you can use it for just about anything as long as you stay within the power limits.

[Lord of nothing]

Nope a Transmitter who work on a ISM Band must be from the Manufacture declared to be in the Specification. The same for CB Radio and PMR446 Radios. 

[radiolistener]

I would like to see how you would install a few km of optical fiber, especially not in your property.

I would like to see how you would install a few km radio-link for high speed data transfer with custom protocol and with no license and no payment for the frequency band... 

Try that outdoors over a few km. Even if ignoring rain, fog and birds, long term positioning would be a big trouble on it's own.

the same issue with radio link. For example, when you use WiFi, other WiFi routers make iterference and leads to connection break.