  We consider secret key generation from relative localization information of a
pair of nodes in a mobile wireless network in the presence of a mobile
eavesdropper. Our problem can be categorized under the source models of
information theoretic secrecy, where the distance between the legitimate nodes
acts as the observed common randomness. We characterize the theoretical limits
on the achievable secret key bit rate, in terms of the observation noise
variance at the legitimate nodes and the eavesdropper. This work provides a
framework that combines information theoretic secrecy and wireless
localization, and proves that the localization information provides a
significant additional resource for secret key generation in mobile wireless
networks.
