近年來，室內空間的導航定位服務需求逐漸增加，在建築物中也能即時追蹤人員或物品等位置，提供更多元化的室內定位服務。隨著Wi-Fi (IEEE 802.11) 基地台普遍分布於室內環境中，以及Wi-Fi已成為行動設備的基本內建功能，因此以Wi-Fi技術為基礎之室內定位服務是目前熱門的研究議題。依目前IEEE 802.11之標準，可利用接收訊號強度(received signal strength)以及訊號傳遞時間(time-of-flight) 來進行室內定位之應用，所以本論文利用IEEE 802.11提供的實際觀測量，進行Wi-Fi (IEEE 802.11)室內定位之接收訊號強度環境特徵演算法與訊號到達時間演算法研究，並以國立成功大學航太系館為實際定位實驗場地。其中，接收訊號強度之環境資料庫建置需利用接收訊號強度具有隨著距離增加而衰減的特性，本論文採用克利金(Kriging)空間推估演算法來擴增環境資料庫，利用已量測之接收訊號強度分布與量測點之相對距離，建立實驗空間之接收訊號強度分布模型，並以函數表示，利用所建立之空間模型推算於未實際量測點之接收訊號強度推估值，於不同環境中，能夠利用本系統迅速地建置環境特徵資料庫，故本論文結合接收訊號強度環境特徵法及克利金法使用於IEEE 802.11室內定位系統。根據本論文實際室內定位實驗結果，在72.2%機率下，使用克利金法擴增資料庫與實際觀測量誤差為3 dBm以下，並同時能改善17.9%定位誤差。另一方面，本論文使用IEEE 802.11v提供的訊號時間量測功能，將訊號的傳送與接收時間標記在發送的訊框中，利用所提供的時間資訊來取得訊號傳遞時間，並據以計算發送器與接收機的距離，因為IEEE 802.11v可以降低訊號傳遞時間量測的複雜性，並解決發送器與接收機之時間同步的問題，所以本論文透過支援IEEE 802.11v標準之Wi-Fi 存取點(Access Point)評估IEEE 802.11v運用於到達時間(Time of Arrival)之室內定位方法。

For the past few years, indoor positioning technology has become an important topic in the development of navigation and position systems. Indoor positioning services currently can track the location of people or objects and provide more applications in buildings. Because Wi-Fi (IEEE 802.11) Access points (APs) are commonly distributed in indoor environments and are the basic equipment in mobile devices, Wi-Fi based positioning systems were developed. With the rapidly gaining popularity of the IEEE 802.11 standard protocol, the main IEEE 802.11-based implementation approaches for an indoor positioning system are either based on the received signal strength (RSS) or signal time-of-flight measurements. This thesis utilizes the fingerprinting approach and the time of arrival approach to develop two indoor positioning systems. The Department of Aeronautics and Astronautics building at National Cheng Kung University in Taiwan is used as an example to demonstrate the implementation of the IEEE 802.11-based indoor positioning system. However, to build a fingerprint database requires lots of time. As the range of the indoor environment becomes larger, labor is increased. To provide better indoor positioning services and to reduce the labor required for the establishment of the positioning system at the same time, an indoor positioning system with an appropriate spatial interpolation method is needed. The advantage of RSS is that signal strength decays as the transmission distance increases, and this signal propagation characteristic is used in an interpolated database with the Kriging algorithm in this thesis. Using the distribution of Reference Points (RPs) at measured points, the signal propagation model of the AP in the building can be built and expressed as a function. The function, as the spatial structure of the environment, can create the RSS database quickly in different environments. Thus, in this thesis, an IEEE 802.11 indoor positioning system based on Kriging fingerprinting method is developed. As shown in the experiment results, with a 72.2% probability, the error of the extended database is under 3 dBm, and improves the error of positioning results by 17.9%. On the other hand, the extended timing measure capability of IEEE 802.11v records the timestamps of the signal transmission and reception into the message frame. The signal time-of-flight is evaluated with timestamps, and the time synchronization is calculated. The extended capability enables the direct use of the time of arrival (TOA) technique and reduces the complication of measuring the signal time-of-flight. The TOA based on the IEEE 802.11v protocol standard with an AP-supported IEEE 802.11v is discussed in the thesis as well.

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