How to transfer file though wireless 435Mhz Module?

Hello there, I have a question that how do I transfer directly from my Arduino camera to another Arduino module? I have a requirement that I only can use RF transmission since we transfer from a far place where wifi is hard to send and RF are far more (A CANSAT project to CUBESAT)
By (ground) Command sent to Arduino camera module (CANSAT) → Picture capture → sent data to ground module.

Very non-trivial, an advanced project.

But first you need to do the sums, how big is the image file, how long do you have to transfer it and what distance do you want to tranfer it ?

Its usually not legal to stream data in the 434Mhz ISM bands, your probably limited to 10% or maybe 1% duty cycle so the scope for sending large images is limited. 2.4Ghz is a better choice.

One dificulty is that a single bit error in the entire image file can corrupt it, so you need to include a protocol so the receiver knows the packet of data is valid and the transmitter knows for sure each packet has been received.

Some of the issues are discussed in these two posts;

https://stuartsprojects.github.io/2021/02/26/Large-Data-Transfers-with-LoRa-Part1.html

https://stuartsprojects.github.io/2021/03/03/Large-Data-Transfers-with-LoRa-Part2.html

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I had to Google CANSAT to see what you are referring to. I know what a CUBESAT is. The problem you must engineer around is the Doppler effect on the signal to and from the CANSAT while it is in motion. A receiver must be able to track the change in frequency. A simple hobby module cannot do that.
Paul

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Thank you! In my case, the hobby module will be like a pathfinder so I would test in the same room but just wireless then after that I would buy a Bigger receiver. And the question is in my case to sent picture to the ground what step should I use to convert it to sent via the transmitter (if you have code for convert picture to i2c then to transmiter, Thank you!)

Thank you ,As i said before since we sent we sent from far place we cant use wifi to sent directly from space to receiver.it about 2Mega pixel picture.

I would not be concerned about doppler myself, we were intially in my own satellite project, but in practice it did not prove to be a problem. FSK digital data was sent and received to a low Earth orbitting satellite using a $5 radio module.

There has recently been established a Worldwide network using ‘Hobby’ modules to receive stuff from space, read about building a $20 hobby groundstation here;

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And the rest of the important details, such as the distance etc ?

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For First about 5 Meter from sender 0M/S ,Then Cansat would be about 40-50 Km about 11M/s , Cubesat about 500 Km with speed at orbital speed.

SD Card (Capture pic then save it then sent),With some temp and Voltage Meter payload and GPS (Power seem not much concern?)
Eh.

Thank you! How long did you store the CubeSat before launch? since i heard about store too long and kill switch broke? it 1/3 Chance to survive?

It was not a ‘CUBESAT’ it was the first of the PocketQubes, much smaller.

I dont remember exactly how long it was before it was loaded into the launch tube, and actually launched, maybe 2-3 months. We had two kill switches in parallel.

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So if one is broke but one good still works?

With a set of LoRa parameters that would cover that distance, a 2Mbyte file would take around 1600 seconds to transfer, possibly a bit less.

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That was the idea.

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Thank you very much!