自古以來，人類便極力於發展準確、穩定的定位系統。隨著智慧型手機（Smartphone）的滲透率逐年攀升，全球衛星導航系統（Global Navigation Satellite Systems, GNSS）廣泛地應用於室外定位（Outdoor Positioning），許多與生活形影不離之適地性服務（Location-Based Service, LBS）皆以GNSS為基礎而延伸。然而，受到陰影效應（Shadowing Effect）與建築物遮蔽所造成訊號衰減等因素，其定位準確度於室內環境中大幅地下降。縱使GNSS於室內表現不佳，室內定位的需求並沒有因此而下降，在室內環境中實現高精準度之定位系統成為了熱門的研究項目。
本篇論文使用智慧型手機作為定位載具，在零硬體裝置架設於室內環境的條件下，僅利用內建於智慧型手機的感測器實現基於行人航位推算演算法（Pedestrian Dead Reckoning, PDR）的多樓層之室內定位系統（Indoor Positioning System, IPS），並且針對其核心運算參數進行優化，包含移動方向、行走步數及步伐長度，最後結合建築資訊模型（Building Information Modeling, BIM）對預測結果進行最佳化。本篇論文所提出之系統於臺灣科技大學電資學院（建築面積約1,315平方公尺）六至八樓進行試驗，總路徑長達306公尺，並以不同身高、體重之使用者進行實測，定位效果可達到平均誤差2.57公尺。

Global Navigation Satellite Systems (GNSS) have been widely used in outdoor navigation. However, the problem of signal attenuation and shadowing effect is serious in an indoor environment. Hence, an accurate smartphone-based multi-floors Indoor Positioning System (IPS) that can guide users through indoor environments, where similar corridors and rooms across multiple floors are commonplace, is highly desired.
In this paper, we have implemented an indoor positioning system using an autonomously configured Pedestrian Dead Reckoning (PDR) scheme without any external sensors on commercially available smartphones. It is able to dynamically adjust core parameters of the PDR during system operation and use the Building Information Modeling (BIM) to optimize predicted results. The system is evaluated in a real practical indoor environment that simulates normal user traveling routes through multiple floors and corridors, conducted by several users with different strides and walking patterns in order to evaluate its performance across different individuals. The evaluation result showed our system can achieve a mean accuracy 2.57m in a multi-level building including an 80m x 16m area on each floor without any floor estimation error.

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