NFC/INS integrated navigation system: The promising combination for pedestrians´ indoor navigation

It is well known that there are many limitations of the current positioning systems either indoors or outdoors. Moreover, most of the current positioning systems require preinstalled infrastructure in the surrounding environment, which is costly in most cases and requires special devices from the user side. The near field communications (NFC), inertial sensors, pressure sensor for height, magnetometers for heading are built in sensors in most modern smart devices. Therefore, they can be used as a low-cost platform for gathering and processing location information. The main target of this work is to reduce the needed infrastructure as much as possible and maximize the use of the components that are built-in or can be connected to the smart devices. The accurate solution which we propose combines the NFC with an inertial navigation system (INS). The advantage of the inertial sensors based approach is that it does not need a preinstalled infrastructure and it starts on basis of a reference location given by the other positioning methods. The NFC approach can work based on simple sensors located in smart shoes that interacts with non-expensive NFC tags preinstalled at the desired floor of the building. Experimental results show that the combination can keep accurate positioning of a pedestrian and limit the error growth of inertial sensors using properly distributed NFC tags. The maximum error in NFC/INS pedestrian dead reckoning (PDR) position is below 1.7 m in the whole track using direct position resetting approach.