I’m trying the antenna delay calibration for dwm1001 included in the MDEK1001 kit.
The API I’m using is UART Shell mode communication.
To correct the antenna delay in UART communication, can I change the value of pg_delay with the command “utpg” and “utps”?
Also, I would like to know how to keep a record of the set values, because these commands return to their default values when the device is turned back on.
Furthermore, is the only way to calibrate dwm1001 that the developer should do is to correct the antenna delay?
If anyone can answer any of these questions, please let me know.
Hi @Naoya
the DWM1001 are pre-calibrated from the manufacturing and normally you dont need to change them.
You are mentioning antenna delay calibration but “utpg” and “utps” are meant to modify the transmit power (PG delay and and TX power) for testing purpose and not to modify antenna a delay. Changing those values will discard its certifications.
I understand that “utpg” and “utps” are the commands to change the transmit power.
You said that you don’t need to correct the antenna delay, but I know from experiments that the relative distance is larger than the real distance at certain anchors.
Hi @Naoya
the antenna delay is calibrated to eliminate the antenna delay variation across the DWM1001 modules. Unfortunately the command for antenna delay is not available.
However the the measured distance is affected also with antenna radiation pattern and with the distance between two nodes (the measured time is not exactly proportional to the distance so there is some internal calibration). However if you will recalibrate to some reference distance then with shorter / longer distance it will be affected by the non-linearity again.
Do a simply test - put anchor and tag on fixed position and then start spinning the tag around its antenna and observe position. You will see that the measured distance will change.
Hi @leapslabs
I had also thought that the radiation pattern of the antenna gain is an important factor in UWB ranging accuracy, but I did not know that the relative distance changes nonlinearly. Thank you very much for the information.
Therefore, what can an engineer do to improve the accuracy of ranging is not to correct the antenna, but to improve the accuracy of anchor position measurement and to place the anchor in the LOS environment as much as possible?
Please let me know if there is any relevant documentation.
I’ve looked over the mdek1001, dwm1001, and dw1000 manuals.