Assessment of WSN and RFID Technologies for Real-Time Occupancy Information

Gulben Calis, Suvil Deora, Nan Li, Burcin Becerik-Gerber, Bhaskar Krishnamachari
Pages 182-188 (2011 Proceedings of the 28th ISARC, Seoul, Korea)

Real-time occupancy information is valuable to the building industry for a wide variety of applications such as on-site safety management, energy conservation, emergency response and so on. With the emergence of various technologies that can potentially be used for indoor location sensing (ILS), the building industry is in search for an ILS solution to provide accurate and cost efficient occupancy information. This study assesses two ILS systems that are built on two promising modalities: radio frequency identification (RFID) and wireless sensor networks (WSNs). Two algorithms were proposed and tested in a computer lab with an area of 235 m2. Six occupants, who were attached with both RFID tags and WSN nodes, were tracked simultaneously. The occupants remained seated throughout the test, and the occupancy was monitored. The results show that the proposed systems were able to provide accurate room level occupancy information majority of the time, and that the choice of algorithm and technology affected the uniformity of the results.

Keywords: Occupancy Detection, Indoor location Sensing (ILS), Radio Frequency Identification (RFID), Wireless Sensor Networks (WSNs), Sequence Based Localization, Nearest Neighbor Localization, Accuracy