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Permalink Reply by Martin Seven on May 4, 2010 at 12:13am

Does it have to be based on recieved signal strength? As far as I know these tend to be unreliable, especially in the GHz range, because of reflections. Most DIY trackers use GPS coordinates and a little bit of trigonometry to solve the IK equation and point each servo in the right direction. For added kick you might implement some kind of trajectory prediction to improve the accuracy and stability of the link.

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Permalink Reply by noman on May 6, 2010 at 8:05am

thanks

i want to tell you my project idea.

i want to move anteena automatically pointing toward the beacon
i want to first implement it for only horizontal mevement using servo
please if you have circuit or code please provide me the data please

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Permalink Reply by Michael King on May 5, 2010 at 8:34am

That is what we did. We used Trig and a trajectory prediction to control the antenna. the antenna was moved 15 times a second even though we were only getting position updates once per second.

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Permalink Reply by James F. on May 5, 2010 at 8:41am

EagleTree makes something that does this already for GPS, it is called Eagle Eyes...

http://readymaderc.com/store/index.php?main_page=product_info&c...

@Michael

Do you by any chance have some code you could share? I think this would be a great addition to the community if it isn't already floating around somewhere in these forums...

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Permalink Reply by Andrew c on May 6, 2010 at 8:57pm

The one way I had thought of to do this would end up being a little complicated. If you just want to worry about horizontal at first, you would need three antennas to receive. You would then have to compute the difference in the times that each ant. receives the signal (which means down to probably the nano second), then do some calculations to get an azimuth.

I know the tech exists, because I know the Military has such systems to track radio transmissions. Building it would be the hard part.

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