Let's shake on it: Extracting secure shared keys from Wi-Fi CSI. (arXiv:2307.05423v1 [cs.CR])

A shared secret key is necessary for encrypted communications. Since Wi-Fi
relies on OFDM, we suggest a method to generate such a key by utilizing Wi-Fi's
channel state information (CSI). CSI is typically reciprocal but very sensitive
to location: While the legitimate Alice and Bob observe the same CSI, an
eavesdropper Eve observes an uncorrelated CSI when positioned over 0.5
wavelength away. We show that if endpoint Bob is shaken, sufficient diversity
is induced in the CSI so that it …

alice channel communications csi encrypted information key keys location secret secret key state wi-fi