3+km HD FPV system using commodity hardware

Hi

Over the last couple of months I have been working on a project that might be of interest to you: https://befinitiv.wordpress.com/wifibroadcast-analog-like-transmission-of-live-video-data/

Basically it is a digital transmission of video data that mimics the (advantageous) properties of an analog link. Although I use cheap WIFI dongles this is not one of the many "I took a raspberry and transmitted my video over WIFI"-projects.

The difference is that I use the cards in injection mode. This allows to send and receive arbitrary WIFI packets. What advantages does this give?

- No association: A receiver always receives data as long as he is in range

- Unidirectional data flow: Normal WIFI uses acknowledgement frames and thus requires a two-way communication channel. Using my project gives the possibility to have an asymmetrical link (->different antenna types for RX and TX)

- Error tolerant: Normal WIFI throws away erroneous frames although they could have contained usable data. My project uses every data it gets.

For FPV usage this means:

- No stalling image feeds as with the other WIFI FPV projects

- No risk of disassociation (which equals to blindness)

- Graceful degradation of camera image instead of stalling (or worse: disassociation) when you are getting out of range

The project is still beta but already usable. On the TX and RX side you can use any linux machine you like. I use on both sides Raspberrys which works just fine. I also ported the whole stack to Android. If I have bystanders I just give them my tablet for joining the FPV fun :)

Using this system I was able to archive a range of 3km without any antenna tracking stuff. At that distance there was still enough power for some more km. But my line of sight was limited to 3km...

In the end, what does it cost? Not much. You just need:

2x Raspberry A+

2x 8€ wifi dongles

1x Raspberry camera

1x Some kind of cheap display

Happy to hear your thoughts/rebuild reports :)

See you,

befinitiv.

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

    • All fixed - silly mistake! Wasn't in the wifibroadcast directory so the .rx/ command wasn't working. CD $wifibroadcast fixed it for anyone else in same boat. Test flight soon! 

      Any progress on OSD??

  • Developer

    In befinitiv's setup instructions there's an optional step to set the TX dongle's output power to 30db.  I was wondering if anyone's done that and if they could post (maybe in dropbox or whatever) the compiled binaries?  I'd just like to save the trouble of having to do that build myself.  Ideally I'd like to have a 10db and a 30db binary (10db is the legal limit here in Japan I think).

    Finding the right WIFI dongle (And patching its kernel driver and firmware)
    This post is a follow-up on . Here I describe my findings on several WIFI dongles that I have tested. — In the last post I presented my raw sender an…
    • 10db is the legal limit here in Japan I think

      Doubtful, that would be 10mW.

      I think you need a bit of work on your dB figuring.  30dB = 1W BTW.

      • Developer

        Ah yes, txs for the correction.

        I'm actually not sure if the limits in Japan.  This web page says 10mW / Mhz but the "/Mhz" part confuses me.. surely it can't mean "per Mhz" or the limit would be very high.

  • It would be really nice if this technique could be ported to something like an ESP8266 module with a decent frontend added for good range.

  • Hi Andreas, I got similar results to you, between 50-100m.  I think these dongles are junk for tx.  I asked CSL several times what the power these dongles are capable of but they couldn't answer - not even vaguely - I suspect they just package/badge a generic chinese dongle and don't really know anything about it.  The driver disk that comes with it just contains files downloaded from ralink website.

    • I'm intending to use these as RX only with an Alfa AWUS051NH V2 as TX.  I'm waiting for these to be shipped over here from the UK so will have some preliminary results by Tuesday.

  • Any word on how putting a wifi booster onboard would help increase range? 

    • Moderator

      My experience (echoed by many) is that a T/X booster usually causes more problems with RF interference, than its worth.

      The best answer is quality antennae on both T/X and R/X sides.

      • Amen!

This reply was deleted.

Activity

DIY Robocars via Twitter
How to use the new @donkey_car graphical UI to edit driving data for better training https://www.youtube.com/watch?v=J5-zHNeNebQ
Monday
DIY Robocars via Twitter
RT @SmallpixelCar: Wrote a program to find the light positions at @circuitlaunch. Here is the hypothesis of the light locations updating ba…
Saturday
DIY Robocars via Twitter
RT @SmallpixelCar: Broke my @HokuyoUsa Lidar today. Luckily the non-cone localization, based on @a1k0n LightSLAM idea, works. It will help…
Thursday
DIY Robocars via Twitter
@gclue_akira CC @NVIDIAEmbedded
Nov 23
DIY Robocars via Twitter
RT @luxonis: OAK-D PoE Autonomous Vehicle (Courtesy of zonyl in our Discord: https://discord.gg/EPsZHkg9Nx) https://t.co/PNDewvJdrb
Nov 23
DIY Robocars via Twitter
RT @f1tenth: It is getting dark and rainy on the F1TENTH racetrack in the @LGSVLSimulator. Testing out the new flood lights for the racetra…
Nov 23
DIY Robocars via Twitter
RT @JoeSpeeds: Live Now! Alex of @IndyAChallenge winning @TU_Muenchen team talking about their racing strategy and open source @OpenRobotic…
Nov 20
DIY Robocars via Twitter
RT @DAVGtech: Live NOW! Alexander Wischnewski of Indy Autonomous Challenge winning TUM team talking racing @diyrobocars @Heavy02011 @Ottawa…
Nov 20
DIY Robocars via Twitter
Incredible training performance with Donkeycar https://www.youtube.com/watch?v=9yy7ASttw04
Nov 9
DIY Robocars via Twitter
RT @JoeSpeeds: Sat Nov 6 Virtual DonkeyCar (and other cars, too) Race. So bring any car? @diyrobocars @IndyAChallenge https://t.co/nZQTff5…
Oct 31
DIY Robocars via Twitter
RT @JoeSpeeds: @chr1sa awesomely scary to see in person as our $1M robot almost clipped the walls as it spun at 140mph. But it was also awe…
Oct 29
DIY Robocars via Twitter
RT @chr1sa: Hey, @a1k0n's amazing "localize by the ceiling lights" @diyrobocars made @hackaday! It's consistently been the fastest in our…
Oct 25
DIY Robocars via Twitter
RT @IMS: It’s only fitting that @BostonDynamics Spot is waving the green flag for today’s @IndyAChallenge! Watch LIVE 👉 https://t.co/NtKnO…
Oct 23
DIY Robocars via Twitter
RT @IndyAChallenge: Congratulations to @TU_Muenchen the winners of the historic @IndyAChallenge and $1M. The first autonomous racecar comp…
Oct 23
DIY Robocars via Twitter
RT @JoeSpeeds: 🏎@TU_Muenchen #ROS 2 @EclipseCyclone #DDS #Zenoh 137mph. Saturday 10am EDT @IndyAChallenge @Twitch http://indyautonomouschallenge.com/stream
Oct 23
DIY Robocars via Twitter
RT @DAVGtech: Another incident: https://t.co/G1pTxQug6B
Oct 23
More…