Affiliations: Department of Computer Science, Yonsei University, Yonsei, Korea
Note: [] Corresponding author: Hojung Cha, Department of Computer
Science, Yonsei University, Yonsei, Korea. E-mail: hjcha@ yonsei.ac.kr; hjcha@cs.yonsei.ac.kr
Abstract: Indoor localization systems typically locate users on their own
local coordinates, while outdoor localization systems use global coordinates.
To achieve seamless localization from outdoors to indoors, a handover technique
that accurately provides a starting position to the indoor localization system
is needed. However, existing schemes assume that a starting position is known a
priori or uses a naïve approach to consider the last location obtained
from GPS as the handover point. In this paper, we propose an accurate handover
scheme that monitors the signal-to-noise ratio (SNR) of the effective GPS
satellites that are selected according to their altitude. We also propose an
energy-efficient handover mechanism that reduces the GPS sampling interval
gradually. Accuracy and energy efficiency are experimentally validated with the
GPS logs obtained in real life.
