室內及室外環境下之GSM/Wi-Fi定位系統分析比較

Performance Comparison between GSM and Wi-Fi Localization in both Indoor and Outdoor Environments

連矩鋒(Chu-Feng Lien)

指導教授 ： 朱浩華

國立臺灣大學/電機資訊學院/資訊工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.00847

摘要

定位系統已被廣泛地應用在各種服務，一旦系統得知人以及物件的位置，服務的種類將可變地更為個性化，這些與位置相關的服務包括導航、地域性的廣告、後勤服務、庫存管控、以及博物館導覽等等，而用來啟動及推廣這類服務的，會是一套可於任何時刻在室內及室外環境下精準定位人及物件的系統。
為了實際地評估建立一個能廣泛覆蓋室內和室外環境的定位系統的可行性，我們選擇目前相當普及的 GSM 和 Wi-Fi 兩個無線網路，將利用這兩個無線網路所構成的定位系統放置到 Smart phone 和 PDA phone 上實現，並且在室內及室外環境﹝例如：辦公室、都市、校園和郊區﹞根據不同演算法﹝Centroid、Weighted Centroid、及 Fingerprinting﹞比較它們的定位表現。結果顯示基于 GSM 的定位系統的平均定位誤差在室內﹝室外﹞的環境下是11﹝113﹞公尺，基于 Wi-Fi 的定位系統在室內(室外)環境下的平均定位誤差為5﹝29﹞公尺，我們認為以這樣的精準度來建構一個可適用於室內及室外的定位系統是可行的。在實驗的過程中，我們討論遇到的幾個實際問題並且比較每種定位方法的優缺點。 在文章的最後，我們提出結合GSM及Wi-Fi兩種網路的混合式定位系統。

關鍵字

GSM定位 ； Wi-Fi定位 ； 室內室外定位 ； 定位系統比較分析 ； 混合式定位系統

並列摘要

Location is considered as one of most widely utilized context information in context-aware computing. Location-aware services leverage the location of people and objects to provide relevant or personalized information and services to users. An enabling tech-nology is a ubiquitous (pervasive) location system that can accurately track positions of people and objects anytime anywhere in both indoor and outdoor environments. Exam-ples of these location-aware services include navigation services, location-based advertisement services, logistical services, inventory control services, museum guide services, etc.
To evaluate feasibility of constructing a practical localization system, which can have wide coverage in both the indoor and outdoor environments, we have selected GSM and Wi-Fi based localization systems, implemented them on commercial GSM/Wi-Fi smart phones and PDAs, and compared their performance under different positioning algo-rithms (e.g., centroid, weighted centroid, and fingerprinting) and different indoor/outdoor environments (e.g., offices, urban and rural areas). Results have shown that the average positional accuracy of a GSM based localization in indoor(outdoor) en-vironment is 11(113) meters, and the average positional accuracy of a Wi-Fi based localization system in indoor(outdoor) environment is 5(29) meters. We consider the accuracy feasible and sufficient for an indoor/outdoor localization system. From our deployment experiences, we discuss several practical problems encountered and com-pare the pros and cons of each localization method. Finally, we propose a GSM/Wi-Fi hybrid localization system that combines the advantages of both GSM/Wi-Fi localiza-tion systems.

並列關鍵字

GSM Localization ； Wi-Fi Localization ； Localization performance comparison ； Indoor/outdoor Localization ； Hybrid Localization System

參考文獻

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