Bi-Directional Beamforming Feedback-Based Firmware-Agnostic WiFi Sensing: An Empirical Study

In the field of WiFi sensing, as an alternative sensing source channel state information (CSI) matrix, use a beamforming feedback matrix (BFM) that is right singular CSI has attracted significant interest owing to its wide availability regarding underlying systems. IEEE 802.11ac/ax standard, station (STA) transmits BFM access point (AP), which uses for precoded multiple-input and multiple-output communications. addition, in same way, AP STA, STA received BFM. Regarding BFM-based extensive real-world experiments were conducted part this study, two key insights reported: Firstly, report identified potential issue related accuracy existing uni-directional frameworks leverage only BFMs transmitted or STA. Such uni-directionality introduces concerns when there capability gap between Thus, experimentally evaluates ability disparity BFMs, shows achieve higher compared from target values are estimated depending on angle departure AP. Secondly, complement gap, paper proposes bi-directional framework, simultaneously leverages The experimental evaluations reveal achieves than terms human localization task.