An Efficient Room-based Indoor Localization Scheme for Wireless Sensor Networks

• Main Authors: Chiu, Yi-Ming, 邱奕銘
• Other Authors: Wang, Kuo-Chen
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/35672002688491887191

碩士 === 國立交通大學 === 資訊科學與工程研究所 === 97 === With rapid advances in wireless and VLSI technologies, applications of wireless sensor networks (WSN), such as target localization in medical environments, are getting more and more popular. In an indoor environment, identifying a target in a logical area, such as a room is more meaningful than identifying a location represented by coordinates. In existing indoor localization algorithms, although their average location estimate errors may be low, they may not provide high accuracy room-level information, which is usually transformed from the predicted coordinates obtained by their localization algorithms. In this thesis, we present a room-based indoor localization scheme using a path-restricted room-level localization algorithm (PRLA) and a fingerprinting based technique for wireless sensor networks. The design of the proposed PRLA localization system meets two objectives. The first is high accuracy of room-level localization and the other is low computational overhead. Experimental results show that by applying our PRLA scheme to the RADAR system, it significantly improves its room-level hit rate from 69% to 94% and reduces the average error distance from 3.19 m to 2.24 m. In addition, the proposed PRLA scheme can be applied to any coordinate-based indoor location system to enhance its room-level hit rate and localization accuracy. We also compared the proposed PRLA with Signpost which is also a room-based localization scheme. Experimental results demonstrate that the delay time to enter a room of the proposed PRLA was one second more than that of Signpost; however the proposed PRLA is more reliable than Signpost because its average room-level hit rate is 20% better than Signpost’s in our experiment when we move around in the same room.