主動式RFID系統設計應用於二維平面定位服務

Active RFID System Design and Implementation for 2D Location Service

吳政樺(Jeng-Hua Wu)

指導教授 ： 李仁貴

國立臺北科技大學/機電學院/電腦與通訊研究所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00276

摘要

隨著無線技術應用的普及化，非接觸式、非直視性的特性以及尺寸小成本低等多項優點，使得無線射頻辨識系統(Radio Frequency Identification, RFID)技術在室內定位系統服務的應用上不但可提升待測物件在移動時的可攜性並且大幅的降低設備的成本。
本文的主旨是製作一個主動式RFID系統來實現二維平面的空間定位服務；在整個研究的過程中，從主動式RFID的設計規劃到系統建置，利用4個主動式Tag作為空間平面的參考位址並和裝配有主動式Tag的目標物，透過無線通訊的方式將電波訊號強度(Received Signal Strength Indicator, RSSI)及具有全球唯一的電子產品碼(Electronic Product Code, EPC)編碼傳回給Reader，經由監控中心收到來自Reader的資訊之後，配合定位演算法來計算出參考Tag和目標物之間位置的幾何關係，以求得目標物所在的位置。
由於無線電波在空間中傳遞時，易遭受到所在地形及障礙物的干擾使得Reader接受到不良的訊號品質而產生誤差，因此，本文研究整理提出了數個可能會影響到定位準確度的相關議題，並且以實驗的方式來探討其距離誤差的影響程度，由實驗結果顯示，本系統使用4參考座標點在5公尺的範圍內，其誤差距離在2.5公尺的誤差率可達95%以上。

關鍵字

無線射頻辨識系統 ； 電子產品碼 ； 接收訊號強度指示 ； 定位

並列摘要

With the popularization of wireless technical applications, The Radio Frequency Identification (RFID) brings many advantages such as non-contact, non-line of sight and the characteristics of small size and low cost. Therefore, not only reduces the cost of equipment very much but also makes measured tracking objects to become easily portable in indoor location sensing while using the RFID technology.
The purport of this article is to implement an active RFID system to realize the 2D level’s location service. In the course of whole research, we made plan and design of active RFID to the systematic construction and accomplish location service. Utilize 4 active tags as the space reference point, and put a tracking object equipped active tag in location area. The reader will receive the unique Electronic Product Code (EPC) and Received Signal Strength Indicator (RSSI) from 4 reference points via wireless communication. To find out the goal object’s location, an application program developed by Visual Basic 6.0 could calculate the geometry position between the 4 reference tags and the tracking object by location algorithm.
Because of the electromagnetic wave propagation on the free space easily interfered by topographic obstruction lead to the reader will receive the bad signal quality. Therefore, this thesis has studied and put in order relevant several topics that may affect the accuracy of location. From the actually measure of experiments, the result shown the distance error will be 2.5 meters within 95 percentage of ratio if this system equipped 4 reference tags in a 5 square meter region.

並列關鍵字

RFID ； EPC ； RSSI ； Location Sensing

參考文獻

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