How to stream camera from Pi over 3G?

Question

Arduino

Hello everyone, I have an idea to get my old quadcopter (MultiWii) off the shelf and make it work on 3G.
The first thing that came to my mind was to control the MultiWii via a PPM signal (1 wire, 8 channels) instead of a PWM signal (3 wires per channel). There was a problem, and how to generate such signals? Raspberry does not seem to be able to create such "fast" updates as in PPM.
It was decided to take the Arduino to generate a signal on the MultiWii, connect the Raspberry via Serial to the Arduino and transmit data from the socket (client joystick position).
Questions:
1) how to correctly and less costly control MultiWii, generate PPM on Pi
2) how to take information from MultiWii (telemetry) and give it to the client
3) how to broadcast a video from Pi to a client (udp + mpeg?) with a general stream of information
4) how to make it all work fine over 3G (there is an unlocked 3G modem and an unlimited SIM card)

Answer 1

For starters, advice - hammer on 3G. delays will be very peppy. Even through Wifi, everything will not be fast. Although if you arrange not FPV at all, then for a sweet soul.
Multiwii is already an arduino. Rather, the microcontroller there is the same as on the Arduino. So just take the firmware and fix it. And you can write there, and pick up telemetry from there.