Let me start by saying that I am new to arduino and am wanting to test the feasibility of a project that I have in mind. I have done some searching and have seen many threads stating that arduinos are not capable of transferring real-time video to a display due to the lower speed of the processors. However, I do not want to display the image, I just want to transmit the NTSC/PAL signal from one location (camera) to another (monitor). Is this possible?
Wikipedia says that ADC for composite video happens anywhere from 3MHz to 250MHz. I was thinking of using a high speed ADC (with 32 bit?) connected to an arduino Due, then transmitted through an RFD900 or similar transmitter. I have a feeling that even the Due is too slow for this but I thought I would check to make sure.
The end goal is for FPV flight of an RC plan. I do not like the fact that current configurations use two different Tx/Rx systems - one for control of the aircraft, and one for video transmission. To me, this seems like a waste of power and an addition of unnecessary weight. Why can't everything be sent through one radio? If an arduino is not powerful enough for this, does anyone have a suggestion of a uC that is? Thanks in advance for the help!
AWOL:
Why not simply use a 2.4GHz/5.xGHz device designed for the job?
I don't get your argument - control normally goes to the craft and video/telemetry comes from the craft - two entirely different channels.
I think you would be hard pressed to find a 2.4GHz camera that has the >40km range of a RDF900. 900MHz is going to transmit long distance more efficiently than 2.4GHz or 5.XGHz.
Current systems have two signals that go from the aircraft to the ground - telemetry and video. Additional cameras mean even more signals. I just wanted to make the communication more "neat" if at all possible since I am planning on controlling the aircraft with a uC anyways.
I think you would be hard pressed to find a 2.4GHz camera that has the >40km range of a RDF900
And that distance was mentioned where, exactly?
I think that you would be a very clever person indeed if you could use your quoted RDF900 to transmit anything resembling PAL or NTSC (or even their close cousins CCIR/RS170)
Air Data transfer rates: 4, 8, 16, 19, 24, 32, 48, 64, 96, 128, 192 and 250 kbit/sec ( 64k/128k default )
UART data transfer rates: 2400, 4800, 9600, 19200, 38400, 57600, 115200 baud ( 57600 default )
(FYI, either system (colour or mono) at broadcast quality has a bandwidth of around 5.5MHz)
I think you'd be better off finding a dedicated analogue system, and sending the telemetry during blanking.
AWOL:
And that distance was mentioned where, exactly?
http://rfdesign.com.au/index.php/rfd900 says it's capable of over 40km with a good antenna. I would have chosen a less expensive and less power hungry antenna if I were going for shorter distances. However, I would like to get some range out of whatever system I decide on.
AWOL:
I think that you would be a very clever person indeed if you could use your quoted RDF900 to transmit anything resembling PAL or NTSC (or even their close cousins CCIR/RS170)(FYI, either system (colour or mono) at broadcast quality has a bandwidth of around 5.5MHz)
I think you'd be better off finding a dedicated analogue system, and sending the telemetry during blanking.
I was afraid that was the case. Even using a low sample rate looks like it would be pushing the limits of the RFD900, not to mention the arduino.
That was my second option. Run video, telemetry, and control all through an analog signal. I'll start down that rabbit hole and see if I can work anything out. Thanks for the help!
I was commenting that the 40km range wasn't mentioned in the original post.
You'll probably find that your government has much to say about the control of UAV out of visual range, and a hefty fine or incarceration may well be an option for you.
Run video, telemetry, and control all through an analog signal.
Again, the video and telemetry is coming back from the UAV, whereas control is going to the UAV.
Different bandwidth requirements entirely.
Your best bet is to read and ask questions in the DIY drone forums. I sometimes look at long range communication, and have not seen anything at the hobby level that will do 40km, especially with one of the sites moving.