BACKGROUND

Location identification for areas in which GPS (Global Positioning Satellite) signal is weak or otherwise insufficient is difficult. This is particularly challenging for indoor tracking as buildings add both hinderance for GPS signal and introduce considerable complexity to tracking as multiple floors and rooms are involved.

This can be a particular challenge in emergency situations where time to identify a location of a person is critical to preventing harm or even saving a life. For structure fires or other rescue situations, quickly locating victims and troubled responders in real-time is of utmost importance. GPS signal is generally not available inside most buildings and any existing infrastructure in a building that is intended to provide indoor positioning usually cannot be relied on due to damage to the structure and the indoor positioning infrastructure.

