Anchor Placment Accuracy

Wireless Connectivity Ultra-Wideband
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Hello,

i have bought the MDEK1000 and have a question about the accuracy of the anchor placement.

How accurate should the anchor placement be, to get the best position values for my tag, or is there an small error?
Anchor Position: X=true_value+error;Y=true_value+error;Z=true_value+error
Error in a space of +/- 5cm? / +/-10cm?

Using Auto configure from the app? or should i measure the room with a Laser Device and calculate the position manual, is this effort worth it?

Thank You

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It depends on how accurate you want the system to be.

Under ideal conditions individual range measurements from the tag to the anchor have an accuracy in the 5-10 cm region. Given that an error in the anchor location of 1 cm isn’t going to have any meaningful impact on the accuracy of the final solution.
If the anchor error is also in the 5-10 cm region then you’re going to start to see a slight degradation in the output accuracy but nothing too large. If it’s 20 cm or more then the anchor error will start to be the main cause of errors.

Having said that a good geometry is probably more important than a good survey. Putting the anchors in the ideal locations even if you can’t measure them quite as accurately is normally going to give better results than putting them in a worse location that’s easier to measure accurately.

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You mentioned “a good geometry”. What geometry should be?

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The main thing is that you want anchors on all sides of the tag. Looking from the tag you want anchors as evenly spaced as possible around you, if they are all in the same direction the accuracy will suffer.

And remember that if height matters to you then the same rule applies to the vertical axis.If all the anchors are at the same height then the vertical accuracy will be poor. If they are all above you then even if they vary in height the position still isn’t going to be great.
The difference is that it’s normally a lot harder to get good variety in height.

Other than that it’s mostly making sure you keep the views between the antennas as clear as possible and avoid any metal objects too close to the antennas.

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Thank you for your reply, this will help me.

Do you know some about this?

From this Post: Distance between anchors and Listener, TX Power
I will place the anchors at 4 concrete pillar, direct at the wall. Is this a Problem?

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My observation is that it might be better to keep some distance to the wall/obstacles if possible (e.g. 15cm). The reason is that reflections from the wall could distort the UWB pulses.

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