無線網路之室內定位研究

A Study on Indoor Localization with Wireless Networks

鄭有廷(You-Ting Jheng)

指導教授 ： 黃永發

朝陽科技大學/資訊學院/資訊與通訊系碩士班/碩士(2010年)

摘要

本論文乃探討無線網路環境之下用於室內(Indoor)之定位，我們應用最小均方誤差(Minimum Mean Square Error，MMSE)演算法作三角定位時，以接收訊號強度(Received Signal Strength，RSS)作定位之精確度受到遮蔽效應(Shadowing Effect)甚大之影響，經由初步模擬中，發現定位之精確度除了與參考點與定位節點之距離有關外，參考點與定位節點間距離之變異量也會影響精確度，因此，考慮參考點與定位節點之距離及參考點間之距離變異量，將其分為內部距離、外部距離變異量，於是我們提出以各距離變異量為權重機制之參考點選擇定位機制，由模擬結果得知，以外部距離變異量之權重參考點選擇法獲得較有效之改善。

關鍵字

參考點選擇 ； 距離變異量 ； 接收訊號強度 ； 室內定位 ； 最小均方誤差 ； 三角定位

並列摘要

This thesis investigates the indoor localization based on minimum mean square error (MMSE) estimation for wireless sensor networks (WSN). With three received signal strength (RSS) of the unknown node, a trilateral localization is performed to position its coordinates. However, the mean square error (MSE) of localization is deteriorated by the shadowing effect. Moreover, the MSE depends on the location of reference nodes. Therefore, in this paper, we investigate the effect of the location of reference nodes and the shadowing effect on localization MSE. Simulation results show that the weighted on distance variance of outer distances between reference nodes can improve more accuracy of localization.

並列關鍵字

Trilateral localization ； Distance ； Variance ； Indoor localization ； MMSE ； RSS

參考文獻

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