以低耗電藍牙裝置之訊號強度為基礎的室內定位方法設計與分析

Design and Analysis of Indoor Localization Based on Received Signal Strength Indicator of Bluetooth Low Energy Devices

朱炳燁(PING-YEH CHU)

指導教授 ： 陳育威

國立臺北科技大學/管理學院/資訊管理研究所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00318

摘要

隨著行動裝置的興起，許多建立在行動裝置上的服務也越來越普及，其中受矚目的服務之一就是適地性服務 (Location Based Service, LBS)，LBS的重點之一就是定位的問題，也就是「如何取得使用者的所在地」。定位的種類大致上可以分為室外定位與室內定位，在室外的定位大多是以GPS為基礎的方式來達成取得使用者位置的目的，但在室內GPS無法發揮很大的效果。室內定位其中一個方法就是無線感測器網路 (wireless sensor network, WSN)，無線感測器網路上經常遇到的問題是硬體成本、數量與監控環境的範圍的權衡，以及無線訊號容易受到環境的干擾。
本論文提出一個建立在無線感測器網路上的定位法，此感測器網路的架構是由搭載藍牙4.0模組的裝置作為固定節點，移動節點則是具有藍牙功能的行動裝置，此架構的優點在於藍牙節點本身成本低廉、藍牙4.0的低耗電傳輸模式下的省電、以及藍牙在行動裝置上的普及性。在定位的演算法方面使用多種方式組合，如兩步驟遞迴定位法之環境參數建模、三角定位法、以及利用監測環境的地圖資訊進行路徑配對等。本論文期望利用藍牙4.0低成本、低功耗、普及性等等的硬體特性，加上以訊號為基礎的各種方法的組合下，達到簡單的運算與操作即可有一定精準度的結果。
經過實驗找出了六組可以在不分藍牙訊號發射器數量，且不分採樣點位置的實驗環境下達成8成定位結果位於三公尺精準度的結果，並分析出方法組合中變化的影響，以及對實驗環境影響進行探討。

關鍵字

室內定位 ； 感測器網路 ； 低耗電藍牙 ； 行動裝置 ； 三角定位

並列摘要

With the blossom of smart mobile devices, more and more content provider provides location based service on mobile device. When users are in indoor environment, we need to use another way to get user’s location. Wireless sensor network (WSN) is a popular method in indoor location. However, there are some problems in WSN – how to get balance in hardware cost, number of devices, signal coverage, and the multipath effect problem. This thesis proposes a location method based on RSSI of Bluetooth low energy (BLE) devices of which advantages are low device cost, energy conservation, and high popularity. The BLE devices are used as fixed nodes and mobile nodes in the WSN environment for the proposed location method. The main concept of the proposed location method is combining some low complexity RSSI based location algorithms, e.g., triangulation, map data based location method, and so on. Thus, there exist more than one hundred combinations. In the experiment result, we find that six methods achieve 80 percent location errors less than three meters. Further, we also discuss the effects of test environment and different combinations.

並列關鍵字

Indoor localization ； wireless sensor network ； Bluetooth low energy ； mobile device ； triangulation

參考文獻

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