@techreport{oai:ipsj.ixsq.nii.ac.jp:00078349,
 author = {勝田, 悦子 and 内山, 彰 and 山口, 弘純 and 東野, 輝夫 and Etsuko, Katsuda and Akira, Uchiyama and Hirozumi, Yamaguchi and Teruo, Higashino},
 issue = {18},
 month = {Nov},
 note = {携帯電話の普及とともに携帯電話にGPSを搭載することが求められるようになり，ナビゲーションなどの目的でGPSを利用する機会が増えている．本研究ではGPSの新しい利用方法として，Signal to Noise Ratio(SNR)などGPSの受信状態を用いて端末が屋内・屋外のどちらに存在するかを判定する方法を提案する．このため，様々な屋内外環境においてGPSの受信状態を収集し，各環境での特性から事前に判別モデルを構築しておくことで，屋内外判定をリアルタイムに実行する．屋内外判定により，屋内外で位置推定法をシームレスに切り替えたり，地図情報と組み合わせた位置推定の精度向上などの実現が期待される．提案手法の精度を確認するため，郊外や都市部など様々な屋内外環境でGPSの信号強度を収集し環境に応じて評価した結果，屋内外が切り替わってから7秒で90%の判定成功率を達成できることを確認した．, Global Positioning System (GPS) has been widely used in our daily life because it is required to equip a cell phone with a GPS receiver for emergency services. In this paper, we propose a novel method using GPS status such as Signal to Noise Ratio (SNR) for estimating whether a GPS receiver is located in an indoor environment or an outdoor environment. To achieve this, we have collected GPS status in various indoor/outdoor environments, and a discriminant function is constructed based on those GPS status. We can discriminate between indoor and outdoor GPS status by the discriminant function. The results of the discrimination can be used for many useful services such as rapid switching of localization methods and localization accuracy enhancement combined with map information. Through real experiments in various environments such as urban and residential areas, we have evaluated the accuracy of the proposed method. The results show that the proposed method achieves the success ratio of 90% in 7 seconds after the indoor/outdoor environments are switched depending on environments.},
 title = {GPS受信状態を用いた屋内外判定法},
 year = {2011}
}