Is it necessary for two devices to be connected to perform Channel Sounding?

[ignatious-p]

Hello,

According to my understanding of Bluetooth Core Specification 6.0, Volume 6, Part H, "Channel Sounding", it is not a requirement that the Initiator and Reflector are in "Peripheral" and "Central" roles during Channel Sounding. There simply must be a way of sending the data between the two devices in a bi-directional manner.

Given that context, here are my questions:

1. I have a couple of nRF54L15 development kits, which I program using NCS V3.0.2. Does the current SDK allow me to modify the Channel Sounding procedure so that I can do it over PAwR or something similar? Do I have granular control like that?

2. According to zephyr/bluetooth/direction.h, there seems to be a way to send connection-less CTE data during direction finding. I believe that the nRF54L15 supports direction finding via AoA and AoD as it is supported in the Direction finding connectionless beacon example. Therefore it seems possible to bodge together a method to do what I propose, however, I am not an expert on this matter. Am I on the right track here?

I greatly appreciate any and all advice/suggestions and corrections. 

[PaKa]

This would be a proprietary solution as the security is mandatory for Bluetooth compliance. For research this may not be a problem so you can judge if it will meet your requirements.