What is the feasibility of two arduinos communicating through radio signals, one on the ground and one in space? If it is feasible how would I do it? If it is not feasible are there any alternatives?
Thanks,
MasterC0829
If you are in the UK I suggest you have a read of this Licence-exempt radio use - Ofcom
What about using a satellite phone? (seriously!)
That sort of radio communication is perfectly possible but very complex - usually because of the very low power that's available in order to keep down the mass of the object that must be launched into space. Think about GPS - your ground based receiver is picking up an incredibly weak signal.
...R
Just use the cell phone network (via Arduino GSM modules).
Lora modules should do that, from a few miles to a few hundreds towards space.
MrC0829:
What is the feasibility of two arduinos communicating through radio signals, one on the ground and one in space? If it is feasible how would I do it? If it is not feasible are there any alternatives?
if your an amateur radio license holder this is certainly feasible, its been done with PICAXEs and an RFM22B for instance.
Its probably possible with licence exempt ISM bands stuff too, even though you are normally then limited to 10mW.
However getting an Arduino to that sort of altitude is neither simple nor cheap, so what had you in mind ?
ard_newbie:
Lora modules should do that, from a few miles to a few hundreds towards space.
Should do, but not known for sure. The fast changing Doppler shift that objects (satellites) generate at that sort of altitude may disrupt the LoRa reception.
Of course it's feasible! Almost every satellite has 2-way communications. I have no idea what equipment is required or what regulatory approvals are required, but if you can get an Arduino into space someone on your team should be in charge of telecommunications. 
And assuming it's in orbit, the distance won't be constant and it will be rarely directly-overhead so you won't have constant communication and you may need more ground stations, etc. If this is government-related the ground stations should already exist, or maybe you just have to contract for bandwidth.
For those of you asking what I am planning to do with an arduino at that altitude, I am planning on launching a cubesat. I have the rocket designs down I just needed help with getting them to communicate, thank you so much to everyone that replied!
MrC0829:
For those of you asking what I am planning to do with an arduino at that altitude, I am planning on launching a cubesat. I have the rocket designs down I just needed help with getting them to communicate, thank you so much to everyone that replied!
"cubesat" suggests to me "satellite".
"satellite" suggests "orbit".
"80 miles" bursts the bubble.
I have the rocket designs down
How are the tests going? Low orbit yet?
Hi,
If you manage to get a cubesat into orbit on a homemade rocket.
You will make Elon cry.... 
Cubesat simplex one way comms has been done many times, google it.
If you need two way comms, have you got your ground station built yet?
Tom... 