DWM1001-dev low position accuracy

Hello everybody,
I measure the distance between an anchor and a tag, but the accuracy is very low and that depends on the antenna direction. also if the distance is less than 20cm I get zero. In my project, I am should to measure the distance between 3 devices, but these devices are located at different points. so i don’t know if the antennas are placed correctly or not. How can i solve this ?
best regards

What are you saying is unspecific and cannot be answered.
You have to be specific if you want an answer. Which application are you talking about and using which HW?

In the contrast I can say that a lot of others are measuring distance and the accuracy is very high…

I have three DWM1001-dev devices, I want to determine the distance between these devices. I tested this with 2 devices, I set one device as an anchor (initiator) and the other as (tag). I read the results through Uart using Tera Term. The results are good if the antennas of both devices are vertical. My question is: how can I determine the distance, although the antenna direction changes when the objects move and this leads to inaccuracy of the system.

You need to keep the antennas vertical, they are linearly polarized and so you will get a polarization mismatch if one is vertical and the other horizontal. This will cost you a lot of signal strength and so accuracy.

If you rotate the unit around the vertical axis you will see a variation in measured range of several cm. This can be minimized by keeping all other metallic objects (including circuit boards) as far away as possible from the antenna but can’t be completely eliminated. It’s simply a fundamental limitation of the antenna.