Intel 8260, FTM (802.11mc) support giving negative RTT measurements

[RS19104]

We are currently trying to set up FTM based on Intel8260 (responder and initiator, where the responder resides in a soft AP). After some playing, it seems that there are a few aspects that need to be worked on the driver. Still, we are getting strange measurements of RTT.

We did not manage to start FTM (the responder was not active) and therefore, on recommendation from authors of "Comparison of 2.4 GHzWiFi FTM- and RSSI-Based Indoor Positioning Methods in Realistic Scenarios", we had to do some changes in the iwlwifi driver which are explained in attach, namely, activation of a specific flag.

The document in attach provides information concerning configuration aspects and changes we did to the code. While FTM now works we are getting negative readings from the RTT.

[Maria_R_Intel]

Hello RS19104,

Thank you for posting on the Intel* Community.

I will send you an e-mail to the e-mail address associated with your community profile. Please reply to the email in order to provide us with some reports to avoid exposing sensitive information in the communities.

Best regards,

Maria R.

Intel Customer Support Technician

[Maria_R_Intel]

Hello RS19104,

Thank you very much for the logs.

We will proceed to check your case internally, please expect an update soon.

Best regards, 

Maria R.  

Intel Customer Support Technician 

[RS19104]

According to prior related work on FTM using the same boards, there is an issue with the driver and the ranging algorithm:

http://www.winlab.rutgers.edu/~gruteser/projects/ftm/faq.htm

Perhaps this helps.

[Maria_R_Intel]

Hello RS19104,

Thank you for your patience.

We sent you a private email requesting some details, we will be waiting for your response.

Best regards, 

Maria R.  

Intel Customer Support Technician