Indeed.
And line of site would be very tricky, unless one was a believer in a flat earth.
To get line of sight at 1000km distance on our bendy Earth, the TX and RX antennas would need to be at an altitude of around 15km each.
I think I replied this on the wrong thread. Here it is again.
1000km is way beyond the radio horizon. This will not be possible at the frequencies of 433, 868 or 915 MHz often found on these LoRa modules. In order to send a radio signal that far without satellites or relay stations will require using much lower frequencies. The maximum frequency you can use for skywave varies day to day. Right now MUF is very high and I was able just a couple of days ago to talk to Italy at 28MHz. But those are exceptional conditions. Normally the MUF is much much lower.
To use anything that would remotely be capable of the distances you are talking about you will need at least a general class amateur license.
Where in the world are you located? Where will the receivers be located?
It depends on the frequency. I can talk all over the world on 25W if I use a lower frequency that can skywave. At hundreds of megahertz like a normal LoRa radio that we get, it doesn't matter how much power you use. Your signal just goes off into space unless the antennas are tall enough to get line of sight.
To add just a little so that you can see that this is something you already know, think about your local radio stations. I can set up a 100KW transmitter on a mountain in Little Rock AR at 92.3MHz and I know for a fact that I cannot hear that station 120 miles away in Memphis. That's 100KW over just 120 miles.
There's more to it than just transmit power. If you don't have line of sight and can't bounce the signal then it doesn't matter how much power you pour into it. The signal just goes off into space. They'll hear you on Mars, but they won't hear you anywhere on earth that they can't see the top of your antenna.
To make matters worse, even with an amateur license, you cannot just do one-way transmissions and certainly not coded data. You also MUST send your call sign in clear readable code or voice at specified intervals, so others can identify who is responsible for the transmission.
In other words, as you have been told, there is NO magic that can be done using an Arduino or anything similar.
If one could do 100MB over 1000km for 100€, no one would have bad internet.
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Indeed.
This is one of those projects where you have to ask yourself, "why doesn't this already exist?". I'm sure many people have had the idea of long range remote controlled robots. Any child can dream that up. Yet if you look for real world examples they are all in the realm of government size entities. NASA might have something like this. The military might. But you definitely don't see this anywhere that a normal person could get their hands on. Not even anything close.
Why not? It's certainly not because nobody has wanted to. The simple answer is that it isn't a trivial matter of hooking a few things up to an Arduino to realize this. You'll need satellites and long range transmitters and special licenses.
What I'm trying to say is that it definitely is not going to happen on a 100 Euro budget. Just isn't going to happen. If that was remotely possible it would have been done. This isn't a case where just nobody has ever tried before.
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What did you enter in ChatG to get that "answer?"
It has... does... before "military" and "NASA" having worldwide remote vehicle operation, private entities were researching crop growth and red tide using the very precursor to the government vehicles. In fact, they (the privates) sold their source, patents and rights to their government.
They did that at VHF frequencies? I'm betting they used HF.
It's possible at HF frequencies, like I said. It's just not legal.
Were they able to:
at
It was called Scan Eagle. It landed by crashing into a pole. Probably not controlled at 1k km, maybe over-the-horizon with satellite due to fuel limit.
Exactly my point. What i was trying to say earlier is that even NASA and the governments can't do what the OP wants to do. They can control drones over vast distances, but not without satellites. And certainly not on a 100 Euro budget.
It's not a matter of resources or money. The laws of physics preclude this sort of thing. The only way to get that sort of radio coverage without satellites or relay stations is to use skywave and at those low frequencies you have really limited bandwidth for digital data. You can do FT8 on 80m wavelengths and make contacts all over the world. But it ain't 100 Mb/s. I don't think it's even Kb/s. EDIT: It's 6 bits per second.
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And that with the QRP operating mode.
Doubtful. I was able to contact South Africa on 80m a few years ago using FT8, but needed 600 watts. 17m is a different story. QRP is fine, but very dependent on time of day and other propagation parameters.
These are indeed the requirements for shortwave radio operation.
(1000km & 100Mb/s) < equipment of 100$ = mission impossible
elf: 1000 km ok, 100Mb ,
, 100$ 
vlf: 1000 km ok, 100Mb no chance, 100$ no chance
hf: 1000km ok, 100Mb no chance, 100$ ok
vhf: 1000km very rarely ok, 100Mb nok, 100$ ok
uhf: 1000km only over sat, 100Mb ok, 100$ no chance
Possible with piracy usage of old satellites, or perhaps there is a chance with a modulation on a laser beam, which is reflected on objects in the sky, directly to Your rover? ....could be a nasa project.
Whats about wimax focussed antenna's over several relais stations? I think wimax can reach some kilometers....100 wimax repeater....will cost a little bit more than 100$.
You have no gsm? two smartphone in GSM 5G would fit Your needings.
I would suggest You to lower the bandwith, the distance or getting more money for Your project!
Hellooo guys! I thought for a lot of time, and i think starlink is the best way to do it.
With it, i would need a portable (smaller version) with at max 200ms of latency and like 20 / 50 mbs of bandwith. Do you think our fellow elon is planning that ?
Depending on what you think is portable, Starlink already achieves that.
Ask him.
i think smth like less than max 50 cms would be great
Yea ofc imma add him on X and tell him "Hey bro could u give me smol starlink plz"
