I keep asking myself why this cannot be done, and so far i have not found an answer i can believe. So i bought a commercial HD Video/Audio sender for home use and plugged in my gopro as a video source, and my flat screen TV as the player, and i connected up these devices and viola..! it worked. So my next thought what is the problem with making this work in a UAV , it is using 5.8Ghz it is cheap to buy, just need to hack it so the antenna is less directional, and we can then have HD in our goggles, or on our screen.
This would be far more preferable to me for a first time FPV flyer as the picture is so poor at 480x240 pixels, you can hardly see if your moving or not.
What do you all think? i know a more elegant solution would be nicer but for now it would work.
sample of what i meant : http://www.maplin.co.uk/wireless-hdmi-video-sender-kit-503801
Comments
@Lucas, i've used some less hardcore hardware from here: http://routerboard.com/ (don't remeber exact model). Cube from copter was connecting to that AP and i had decoder connected directly to AP through ethernet. I can't say how long did it go as i was not willing to let copter go out of sight..
@Steve, depending on the application 2-3 seconds latency is actually not that bad at all - though I have to admit i never had it THAT bad (on other hand, I've been only using it one 2 occasions) - i'd say 200-300ms was something we had.
I've been flying on some rallying events and copter-camera was just one of the cameras used. TV guys were constantly recording all 4-5 cameras on the field and then doing some replays and so on - would it be air of something else.. Now if delay is 0.3secs (worst that I had) you have to be really carefully looking for it to see that you've now overlapped some 8 frames. I've been perfectionist, but I think there are more challenging things to solve than that tiny delay.. :)
There have been a few attempts to stream digital video over WLAN:
http://diydrones.com/profiles/blogs/digital-fpv-with-x8
http://www.rcgroups.com/forums/showthread.php?t=1185942
http://fpvlab.com/forums/showthread.php?4869-The-complexities-of-st...
I think there is much potential in this since WLAN is the most popular and most advanced digital transmission technology. In view of the Wifi range-records, range shouldn't be a problem. The main problem is, as mentioned above, the latency.
But if those problems could be solved, this would be the best and most flexible solution.
Jaan, we were using 2 AeroHive AP170's on either side of the field, hidden SSID's and running on 5ghz only. Still just the fact of tons of android and iphone devices scanning that frequency range greatly reduced the range. We even tried putting a patch antenna (forget the exact specs) on one of the AP's...didn't help much.
Can you share what AP you guys used? We just used what was already in place as our whole network is AeroHive.
re: teradek
did anyone try bolts?
as to cube's.. first of all, must use 5ghz
second, use _good_ pro-grade hotspot hardware
third, turn off network id broadcasting to avoid everyone trying to plug their stupid iphone to your wifi
you can't use it for fpv flying, but they will give you great footage for tv streaming (been there, done that)
:)
We used the teradeks as well, it's pretty limited, but also very good on weight. Our best range was 175ft in a typical (read, uncontrollable) environment. Do not rely on commercial 802.11 standard for FPV or RT streaming--it's not built for the application. We've had better success with Boxx units, but they are 5x the weight/power. They work great on the skycam cable setups though.
Forget about both a Epic + Boxx unit... closest is maybe a Sony Nex camera.
I just wanted to comment and say that we use the Teradek Cube where I work. Now keep in mind that we have the older Cube 200, so the newer one may be better.
I would not use these as a solution on my copter. They work great in a rural or low traffic area, but get a few hundred wireless AP's and clients around them and they start to flake out. Every time they glitch the stream becomes more delayed. We've seen delays up to 3 seconds before.
We were attempting to use them to stream football games. When testing with the stadium empty and 2 AP's on either side of the stadium we could get perfect coverage anywhere in the stadium. However once it was game time and there were 100's of fans with smartphones that were scanning for AP's, signal went to crap and you had to be pretty much standing on the AP. Maybe better antennas or some kind of booster could fix this, idk. Also keep in mind that they are quite heavy for their size, all aluminum construction I believe.
They do put out beautiful video when they work though :)
Hi. I don't want to rain on anybody's parade but the Moore law or any other kind of "magical exponential thinking" apply very poorly to wireless technologies, mostly because of that pesky "Shannon limit" thing. Every time a new technology comes in that increase significantly the data rate, the range tend to be significantly reduced. That how things works.
Now, when it comes to video, HDMI carry uncompressed video, approximately 200 Mbps of data for 720p. Even with directional antennas, it's quite hard to transmit that much data beyond a hundred meter. Ok for a quad, but for a plane, that's a real challenge.
Kudos for anybody that can get some actual range with a HD digital video link :D
Yea, there was a IndiGoGo project that was using the SteadiDrone QU4D platform to build an iPad controlled APM Quad, not sure what happened with it but they had claimed their top package would include HD Video.
Hi Jaan, have you seen the price of these units $1700, we all know in the Electronics industry this will come down, but when? i think this needs an open-source type of project to kick-start it, i would support it.
http://www.teradek.com/pages/bolt
http://www.teradek.com/pages/cube
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