RFID Based Indoor Location Sensing System

Abstract

Location sensing or perceive the location of the particular object, can be categorized as an outdoor location sensing and indoor location sensing. Global Positioning System (GPS) is used for outdoor location sensing as a well established and well known technology. However, there is no precise way to track and locate objects in an indoor environment. Further it is very difficult to manage frequently updated stock lists in such environments with a higher number of objects. This challenge can be achieved with the concept of Radio Frequency Identification (RFID). In this research a low cost RFID based indoor location sensing system is suggested to correctly locate the objects and automatically update stock list frequently. According to this method a unique tag is assigned to each object located in the environment. This unique tag is identified according to a method created by combining the Synthetic Aperture Radar (SAR) concept and triangulation technique. Low cost is achieved with passive RFID technology and single reader concept instead of using multiple readers for tag identification. The reader is moved along a V shaped track, placed closer to the ceiling level and tag readings of objects are obtained at pre-defined reading points on the track. Then using gathered data tag locations are calculated according to triangulation technique. Those calculated locations are compared with the corner coordinates of the rack to find the rack in which the tag is currently present. Further improvements are focused on enhancing system performance and reducing the number of database alterations.