Hi,
I got a module that can do 2D direction finding, and now I want to do 3D direction finding with some simple modifications. My idea is to change the original two PCB antennas into four, and then switch the horizontal and vertical antennas to achieve 3D direction finding. Is this possible?
What should I pay attention to when designing this antenna?
What these two antennas looks like now and what I think.
Certainly possible in theory. In theory you only need 3 antennas, you could keep one of them common between the orientations.
One issue is that the PDoA expects the two antennas to have the same trace lengths and delays. As soon as you put any sort of switching logic in there it gets trickier to keep things identical.
Thank you!
You have reminded me of this, the trace lengths will also affect the accuracy of PDOA, I will think about whether there is any way to solve this problem.
Maybe you can do PDoA calibration for each pair of the antennas, before real measurement, to remove the trace length difference.
Thank you,
You mean, make the tag and the base station form a standard AOA 0° and record the error at this time, and then subtract this error in the code?
Yes, something like that.