具距離校正機制之適應性BLE定位系統

An Adaptive Bluetooth Low Energy Positioning System with Range Correction Mechanism

簡銘甫(MING-FU CHIEN)

指導教授 ： 朱鴻棋

朝陽科技大學/資訊學院/資訊與通訊系/碩士(2018年)

摘要

由於智慧型手機被廣泛的使用，使得在室內的定位服務近幾年受到重視且室內定位準確度日漸重要性。目前最被廣為使用的GPS則在室內環境中不適用，而其他室內的定位技術大多數都有著高誤差或是需要附加一些額外且特殊的硬體設備的缺點。故本論文提出依據環境當前的變動來彈性調整環境衰減因子並運用訊號距離補償機制的演算法以降低訊號不穩定所造成的定位準確率下降。所提方法主要由三個階段組成：首先利用事前的訊號與距離的估算選擇適當的環境衰減因子，其次為根據距離估算結果依狀況進行適當的補償機制，最後則將修正後的距離估算結果以三角定位法來進行定位。實驗結果顯示所提出的方法的平均定位誤差小於0.5公尺，遠優於一些現有的室內定位方法並呈現系統準確性與實用性。對研究結果探討後發現環境衰減因子(n)對於室內定位準確的影響相當重要，不同的環境中給予適合的環境衰減因子，能有效的提升定位準確度。

關鍵字

接收訊號強度定位法 ； 低功耗藍牙 ； 補償機制 ； 衰減因子 ； 室內定位

並列摘要

Due to smart phones are widely used in indoor positioning services, making the indoor positioning accuracy increasingly important. The most commonly used GPS is not available in the indoor environment, while most other indoor positioning techniques have the disadvantage of high errors or attaching some extra and special hard equipment. This thesis proposes an algorithm to change the environmental attenuation factor and compensation mechanism according to the current situation of the environment, and reduce the signal anomaly caused by the decrease of positioning accuracy. The method consists of three stages: First, calculate the current environmental attenuation factor by distance and signal. Secondly, compensate the lack of signal distance according to the compensation mechanism. Finally, the triangulation method and the corrected distance estimation are used to positioned result. The experimental results show that the average positioning error of the proposed method is less than 0.5 meter, which is better than some existing indoor positioning methods, and system provides accuracy and practicality. The research results show that the environmental attenuation factor (n) is very important to the accuracy of indoor positioning, and the suitable environment attenuation factor is render in different environments, which can effectively improve the accuracy of positioning.

並列關鍵字

BLE ； RSSI ； Compensation Mechanism ； Attenuation Factor ； Indoor Positioning

參考文獻

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