A Base Station Localization Scheme over Android

• Main Authors: Chao-Feng Lin, 林晁鋒
• Other Authors: Ji-Han Jiang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/62395064680827367734

碩士 === 國立雲林科技大學 === 電機工程系碩士班 === 99 === As far as network deployment or topology is concerned, location information of certain nodes is essential for many applications like route discovery, disaster relief, and location-based services. Nowadays localization has become an important technique of avail to people’s everyday lives. Yet there are quantities of wireless nodes such as indoor base stations whose accurate locations remain unknown or even hard to acquire. As a remedy, this thesis is leveraging the use of Android handsets that feature portability and more computing capability to collect data for localization and display experiment results thereof. Our treatment is to exploit Android handsets equipped with the GPS (Global Positioning System) module to carry out the localization process. Our objective is to locate GPS-incapable wireless nodes by means of the received signal strengths from these sites. Nonetheless, radio signal strengths are easily influenced by the environment, humidity and temperature, causing difficulties while determining environmental parameters from the collected coordinate samples, not to mention localization assessments. This thesis presents hybrid means to incorporate Received Signal Strength Indication used in range-based schemes with the notion of ER (Estimative Region) adopted in the range –free method to refine the region of interest for localization. Our scheme operates without involved computations so that reference coordinates can be unlimited in number such as to accommodate more usable coordinates. Our methodology can also mitigate the errors of estimation resulting from different radio signal propagation scenarios. Further, we propose a Reduced ER method that takes an additional parameter to narrow ER size for ameliorating localization accuracy. Finally, experiments are conducted to demonstrate our performance results through Google Map, on the handset and through quantitative comparisons with trilateration under different settings. Performance results show the effectiveness of our development. Our proposed approaches lend themselves to several applications including network assisted handover, Wi-Fi Positioning System, and object tracking in wireless sensor networks.