Seeking Guidance on ESP32 DW3000 Antenna Delay Calibration Process (Autocalibration)

[Schven04]

Hi,

@theophilusezra

how can we address this multipath issue?

Which multipath issue did you mean here?

@theophilusezra

I have a few questions about your program when implemented in the Arduino IDE. Could you correct my understanding of your program?

Yes of course, I can if you have any questions.

@theophilusezra

These antenna delays are iterated within a range from A to B, and then a comparison is made with similar values from actual measurements and experiments. Is this understanding correct?

Yes basicly this is an simple evolutionary algorithm. The comparison is made with a laser measurement for a precise measurement of the range between the devices.

@theophilusezra

Furthermore, in your calibration, you’re using the same anchor and tag communication (single-sided ranging communication system), correct? How many devices are needed to perform the calibration? Is it sufficient to have just two devices as anchor and tag?

Which kind of measurement you are unsing isn’t really relevant I would say. The script I provided you is the implementation from the example. I am at the point where I like to test what kind measurement is the best for the calibatrion process. At the end you are compare to distances. The APS014 sayes they are using TWR for the ranging measurement. This is I think more a symetric double-sided two-way ranging and not a SS-TWR.

Because in a simple SS-TWR you migth be dealing with clock-drift errors and in DS-TWR the clock drift isn’t that relative anymore. But this is the point where I am now and trying to understand what happenend.

@theophilusezra

How many devices are needed to perform the calibration? Is it sufficient to have just two devices as anchor and tag?

@theophilusezra

I have one more question, does the calibration process require looping ranging (TWR) or does it just use the iteration program?

So for the antenna calibration process, which is described in ASP014, you need 3 or more devices.The device should be placed in a LOS direction with a known range (for exmaple a triangle). Measure the distance with an laser or an other highly precise distance measurement unit. After that you are setting the antenna delay to 0 for all devices. Than you doing an range of measurements (for example 200) from and to each device (1-2,1-3, 2-1,2-3,3-1,3-2). With the measurements done, you calcuate the average distance for that.
Thats basicly the ranging process, after that you should use the script I am provided.

Cheers,
Sven