Get Unique Id of responder via initiator

I am a newbie in UWB.

In my case, I will measure distance between devices and detect which zone initiator is located.

One initiator may be interacted with more than one responder. That’s why I need to know which responder sends message. Could you support me to reach responder unique ID via initiator?

UWB Deice: DWM-1001C
Used Code: GitHub - thotro/arduino-dw1000: A library that offers functionality to use Decawave's DW1000 chips/modules with Arduino.
Data Read: via UArt