International Journal of Electronics Communication and Computer Engineering
Global Navigation Satellite Systems (GNSS), which are widely used today by positioning and navigations systems, are becoming increasingly important in daily life. GNSS, however, do not work well in indoor environments due to the satellite signal outages that occur in closed structures. Yet the demand for indoor positioning systems is growing as handheld devices become cheaper. Consequently, position estimation is a problem that has been addressed using a variety of technologies. This paper classifies indoor positioning technologies into four types, Radio Frequency (RF), proximity detection, triangulation, and scene analysis, of which the final two are the most common for wireless sensor networks.