Fundamental Limits of Wideband Cooperative Localization via Fisher Information

Abstract

Determination of position accuracy for geolocation is a fundamental issue in wireless sensor networks. In a dense obstacle environment, anchors (or base stations) may not be able to provide sufficient localization information to agents because of radio blockage or limited range. In such cases, cooperation among agents (or mobile stations) can be very helpful. In this paper, we develop a model for cooperative localization based on time-of-arrival (TOA) ranging information and derive the position error bound (PEB) for agents in the network using information inequality. Equivalent Fisher information (EFI), which has been applied in the single agent localization case (Sen and Win, 2007), is employed to characterize the localization accuracy. From analysis, we also show that anchors and agents are essentially equivalent in our unified cooperative localization model.