RFID based indoor navigational aid for persons with severe visual impairments

A flexible, low cost, and portable indoor navigational aid for persons who are blind or have severe visual impairments remains an unmet need and a technical challenge. Whereas devices using global positioning system (GPS) signals hold promise for navigational assistance in the outdoor environment, they do not work where GPS signals are absent or greatly attenuated. Thus a network of navigational beacons is needed for the indoor environment. This paper describes the promise of an indoor navigational aid that relies on a network of custom extended-range RFID tags. RFID (radio-frequency identification) technology has the advantages of being low cost, unobtrusive, and highly flexible in the sense that sight impaired travelers can use personalized RFID tags to mark indoor locations of their particular interest. However, commercially available RFID tags have very short detection ranges. To make them suitable as indoor electronic beacons, their range of detection must be greatly extended. Some of the technical challenges and proposed solutions that can extend the detection range are discussed in this paper following an overview of the proposed RFID based indoor navigational aid.