Wikipedia confirmed my suspicions that the Predator UAV uses a satellite link. I imagine that most army robots will be similar, using very costly but high-bandwidth and high-reliability systems that you won't have access to.
Option 2: There's got to be a radio camera that broadcasts and receives via analog radio rather than digital. This will be much harder to integrate into an autonomous sensor suite (you'd need to convert it to a digital signal before processing), but if it is only for human usage (i.e. the driver looks at the screen, then decides what to do), an analog link should be good.
Option 3: Get something that broadcasts over a wireless standard (802.11b/g/n), and you'll have pretty ridiculous amounts of bandwidth, but may have to deal with interference from other consumer devices using that same frequency band.
Example: This is a webcam that works over wi-fi with a 640x480 resolution -
http://www.amazon.com/D-Link-DCS-100.../dp/B000067JZF
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Yeah, I was thinking about that but I really wanted to have it all go over one line. I want to be able to go at least a mile and the maxstream modems are perfect for that but i need a camera to see where im going lol but i'm stuck as to how to stream that back at a decient speed...
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You can get wifi antennas that point in a certain direction to increase the power of the signal by concentrating it. One of my coworkers who was outside of the DSL region for his city got a friend to subscribe to the DSL for him, then bought some Wifi super-antennas to broadcast over about 3 miles from his friend's house to his barn. Problem is, the antennas need to be very carefully aimed, which will be a problem with a moving robot.
19.2kbps is a pretty low bandwidth but if, for instance, you only go for 5fps, it could be done. You'd need to write an image compressor on the robot side, because 19.2kbps of raw images at 5fps would be 5 20x20 grayscale images per second.
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This is a 5fps 320x240 resolution grayscale video that runs at 14.4kbps of 1281's 2006 robot pushing another robot at the waterloo regional last year. So it can be done, and I think the end video would be useful for a driver trying to drive. HOWEVER: This is encoded with the xvid codec, which means that each frame is dependant on the frame before it, and vastly increases the complexity of encoding. That is to say, I don't think a teeny embedded processor will be doing xvid encoding on the fly. The difference in size and quality between this and a 14.4kbps video encoded with a non-time-dependant compressor would probably be enormous. To get an idea of the kind of quality to expect, compress some .jpg files so that they are each 480 bytes, and that'll give you an idea of how much bandwidth you have to work with at 5fps@19.2kbps.