A Robust RFID-Based Method for Precise Indoor Positioning

A robust method for precise indoor positioning utilizing Radio Frequency Identification (RFID) technology is described. The indoor environment is partitioned into discrete locations, and a set of RFID tags are scattered in the environment. Sample reading patterns of RFID tags are collected at each location by an RFID reader. A pattern recognition and classification method is used, when human, vehicle, or other carrier moves around the environment with an RFID reader, to estimate its physical location based on the reading pattern. The resulting estimation error is within one meter. The method is adaptive to different tag distributions, reader ranges, tag reading defects, and other alterable physical constraints. Results from extensive experiments show that the described method is a robust and cost-saving solution to indoor positioning problems in logistics industry. A provisional US patent is granted on the described method.