Augmenting commercial wireless transceivers with time-of-arrival positioning

The augmentation of commercial wireless hardware with time-of-arrival (ToA) estimation enables pervasive wireless networks to serve additionally as positioning systems. ToA-augmented wireless links offer the ability to provide accurate localization in environments not served by global navigation satellite systems (GNSS) with greater accuracy than inertial sensing systems and wireless fingerprinting. In this paper we propose the augmentation of IEEE 802.11 commercial hardware with ToA through an add-on hardware module. Two processing architectures are introduced, loopback and loopback with probing, to leverage the ToA module. The calibration of local device clocks due to unstable frequency references is also presented. Finally, a discussion of positioning algorithms with simulations demonstrates the efficacy of the proposed ToA module to provide high-precision, low-cost positioning without the addition of significant system infrastructure.