無線網路下藉由混和網路存取點的重要性之精準的室內定位技術

Accurate Indoor Location Estimation by Incorporating the Importance of Access Points in Wireless Local Area Networks

黃浩儒(Hao-Ru Huang)

指導教授 ： 林宗男

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.03141

摘要

本篇論文的焦點是無線網路的是內定位。我們觀察到在做定位估算時，每個無線網路存取點(AP)的貢獻度是不同的。這篇論文的主要貢獻可以分為兩個部分。第一，我們提供一個新的方法去量測AP 階級的重要性。在不同的地方利用訊號的鑑別度量化每一個AP 的重要性。我們利用如此的數值關連來選擇重要的AP 來避免不必要的計算。選擇重要的AP意味著佈建AP在較有鑑別度的位置。我們的方法可以有效的應用在AP的佈建。第二，這些重要性進一步地嵌入我們的定位系統。我
們提供一個加權重的零核函數這些權重影響的AP 是有區別的。那就是愈重要的AP 分配愈大的權重。此外，我們發展一個概似熵的函數來避免突然劇烈改變的權重。我們的定位系統是發展在一個真實的無線網路環境，我們蒐集真實量測到的訊號強度(RSS)。實驗結果顯示考慮這些不同的重要性在定位的精準度有重大的提升。

關鍵字

室內定位 ； 無線網路 ； 選擇無線網路存取點 ； 特徵指紋定位 ； 無線網路存取點的布建

並列摘要

This study focuses on indoor localization in Wireless Local Area Networks (WLANs).
We investigate the unequal contribution of each access point (AP) on location estimation.
The main contribution is two parts.
First, a novel mechanism is proposed to measure the degrees of the AP importance.
The importance of each AP is quantified by the signal discrimination between distinct locations.
We utilize such numerical relevancies to select important APs to avoid unnecessary calculations.
To select the important AP means place the AP in the discriminative positions.
Our method can efficiently apply to AP placement.
Second, the importance is further embedded into our positioning system.
We provide a weighted kernel function where the effect of APs is differentiated.
That is, the larger weights are assigned to the more important APs.
Moreover, we develop a quasi entropy function to avoid an abrupt change on the weights.
Our positioning system is developed in a real-world WLAN environment, where the realistic measurement of receive signal strength (RSS) is collected.
Experimental results show that the positioning accuracy is significantly improved by taking the
different importance into consideration.

並列關鍵字

indoor localization ； wireless local area networks ； AP selection ； location fingerprinting ； AP placement

參考文獻

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wireless communications on highways of the future,” IEEE Communications

[3] S. Tekinay, “Wireless geolocation systems and services,” IEEE Communications

[4] K. Mikkel, Baun, “A taxonomy for radio location fingerprinting,” Lecture

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