I. Introduction
For many years, people have studied indoor localization techniques like GPS, IR, RFID, Zigbee, WiFi, Bluetooth, Ultrasound, etc. [1]–[4] Until now there is still no standard for indoor positioning system due to several challenges:
RF solutions are not safe to use in some environments (hospitals, airplanes, etc.)
All solutions require extra infrastructural materials which brings additional costs (IR, Ultrasound, etc.)
Some solutions have a very low accuracy which makes them unsuitable for indoor environments (GPS)