Chen's Learning Note

Sensing measurements are performed during a sensing  measurement instance.Each sensing measurement instance is  assigned a Measurement Instance Identifier . Two variants of  sensing measurement instances exist: • Trigger-Based (TB). In this variant, the sensing initiator  is an AP, and one or more clients assume the role of  sensing responders. • Non-TB . In this variant, the sensing initiator is a client,  and only one STA (an AP) assumes the role of sensing  responder. Both variants allow for measurements to be obtained in the  uplink (AP is the sensing receiver), downlink (AP is the  sensing transmitter), or both. Notice that the TB variant is the  only one allowing multistatic sensing. Both variants allow for  sensing measurements results to be reported if requested by  using sensing measurement reports.  CSI is the only sensing  measurement defined by TGbf, and as such, is the only sensing  measurement rep...

  A WLAN sensing procedure uses two sets of roles: •  Sensing initiator and sensing responder : to discriminate  between the STA, called sensing initiator, that initiates the  WLAN sensing procedure (i.e., the STA that supports a  sensing application), and the STA, called sensing responder,  that participates in the procedure by responding to  the sensing initiator. •  Sensing transmitter and sensing receiver : to discriminate  between a STA, called sensing transmitter, that transmits  PPDUs to allow for sensing measurements and a STA,  called sensing receiver, that receives PPDUs sent by the  sensing transmitter to perform sensing measurement. Below figure summarizes the possible role combinations and associated  message exchanges.  We can  first observe that the sensing measurements are obtained with  the transmission of NDPs. And then, the  sensing report can only be sent by a sensing responder actin...

Sensing systems can be categorized based on the number of devices used to obtain sensing measurements.  These  architectures are naturally supported by Wi-Fi systems: • Monostatic requires only one station (STA) and at least  two antennas. This architecture does not need any communication  or coordination between multiple STAs from  a sensing point-of-view and therefore does not need to  be specifically addressed by a Wi-Fi sensing standard as  long as it respects IEEE 802.11 mandatory requirements  (e.g., channel access). • Bistatic requires a communication between two STAs. It  can thus be achieved between an AP and a client (a client  being typically connected to a single AP). • Multistatic requires communication involving more than  two STAs and can thus be achieved between an AP and  multiple clients either by obtaining measurements using  signals transmitted by multiple clients or by transmitting  signals that a...