Abstract
Whereas outdoor navigation systems typically rely upon global positioning system (GPS), indoor systems have to rely upon different techniques for localizing the user, as GPS signals cannot be received indoors. Over the past decade various indoor navigation systems have been developed. This paper provides a comprehensive overview of existing indoor navigation systems and analyzes the different techniques used for: (1) locating the user; (2) planning a path; (3) representing the environment and (4) interacting with the user. Our survey identifies a number of research issues that could facilitate large-scale deployment of indoor navigation systems.