On the Performance Analysis of Wifi Based Localization

Currently, WiFi (or IEEE 802.11) enabled infrastructures and devices have become ubiquitous, which makes it promising to provide indoor positioning services via WiFi signals. However, most existing studies on its performance are carried out based on simulations and experiments, and it is still challenging to mathematically characterize the localization error. Therefore, in this paper, the Cramer-Rao lower bound (CRLB) for the localization error by using WiFi signals is established and enables us to carry out a theoretical analysis on the fundamentals of WiFi based localization. Extensive experiments based on the well-known WiFi fingerprint-based localization are then carried out and confirm the correctness of the proposed CRLB model as well as the analysis.