基於RFID考量接收訊號強度定位下之移動狀態下無縫式個人化多媒體服務

RFID Seamless Personal Multimedia Service Based on Considering Received Signal Strength Indication

張智皓(Chih-Hao Chang)

指導教授 ： 簡銘伸

國立虎尾科技大學/電機資訊學院/資訊工程研究所/碩士(2011年)

摘要

在目前的環境中會有許多播放裝置與顯示裝置，透過預先定義之內容，提供相同的服務與資訊內容給不同的使用者；換言之，此類型的資訊服務系統無法針對不同的使用者提供個人化與差異化的服務，而且，當使用者移動到不同的地點或區域時，需要再次重新啟動系統才能得到多媒體服務。除此之外，使用者所選取的多媒體服務，也會因為使用者在不同區域或地點中移動而中斷，無法提供無縫式的多媒體播放與服務。
近年來隨著科技進步，定位技術以及相關應用也日益普及，定位技術主要可分為室內定位以及室外定位，室外定位中主要使用全球衛星定位系統(Global Positioning System，GPS)，目前已廣泛使用在汽車導航與定位中，但因為在室內無法接收到全球衛星定位系統的衛星訊號，亦或是衛星訊號品質不佳，所以全球衛星定位系統無法使用在室內定位中。而室內定位技術中，因為無線射頻辨識(Radio Frequency Identification，RFID)有非接觸式感應、重複讀寫、成本低以及佈署方便等優點，所以相當流行。本論文提出行動預測方法，結合無線射頻辨識技術辨識使用者和接收訊號強度(Received Signal Strength Indication，RSSI)訊號值進行行動預測，首先使用無線射頻辨識技術辨識使用者的電子標籤，根據電子標籤的接收訊號強度找出使用者在感應環境中的相對位置，再計算單位時間內使用者所移動的距離與方向，藉此預測下一個移動的位置。
而資料庫記錄使用者的多媒體設定以及感應環境中移動的相關紀錄，因為無線射頻辨識技術具有唯一識別碼(Unique ID)特性，可以將不同的使用者予以識別並區別，而後系統可根據個別使用者的電子標籤從資料庫中存取個人化的使用者的資料，再依此提供個人化的多媒體服務。
本論文整合被動式無線射頻辨識技術以及行動預測演算法，用來實現無縫式個人化的即時多媒體服務，使用者在感應環境中隨時隨地都能取得個人化的多媒體服務，且多媒體服務並不會因為使用者的移動而中斷，也無須再次從頭啟動多媒體內容。
本論文所提出的系統，讓使用者依照個人需求得到個人化的服務，而不是一般未經篩選的服務。透過基於RSSI訊號行動預測，能夠幫助系統提高預測使用者位置的準確度，當使用者欲移動到下一個區域時，系統也能事先通知下一個區域的多媒體播放器載入對應使用者無線射頻標籤之資料，達成無縫式的多媒體服務。

關鍵字

RFID ； Mobility Prediction ； Multimedia services

並列摘要

Today, there are many multimedia player devices and display devices in the environment. The predefined content is provided which may be the same service and information for different users. In other words, this types of information service cannot provide personalized and differentiated services for different users. In addition, user needs to restart the system to get multimedia services when user moves to different location or region. In other words, the original or current multimedia services provided to the user will be cancelled when user moves to different location or region. It means that this type system cannot provide seamless multimedia services to users.
Recently, localization technology and related applications were improved due to technology rapid development. The localization technology can be divided into two types: indoor localization and outdoor localization. The most popular outdoor localization is Global Positioning System (GPS). GPS system is widely used in automobile navigation and positioning system. However, satellite signals cannot receive in indoor environment or the quality of satellite signals is low. Therefore, to enhance the utilization of indoor localization, Radio Frequency Identification (RFID) can be used as the popular wireless induction system. RFID technology has a lot of advantages such as long read range, untouched write and read, multiple tag read/write, and low cost of deployment.
In this thesis, RFID Seamless Personal Multimedia Service Based on Considering Received Signal Strength Indication is proposed which consists of a mobility prediction method and the RFID system. The proposed service integrates RFID system for user identification. Via Received Signal Strength Indication (RSSI) signal value as mobility prediction method, the mobility or location can be evaluated and predicted. First, based on RFID technology, user’s tag can be identified. Then, according to RSSI signal value of the specific tag, user's relative position in the induction environment can be evaluated. At last, the moving distance and direction can be calculated in unit time for predicting next moving position.
In addition to RFID system, the database stores users’ on demand multimedia setting and relation information. Since RFID technology can identify different users, the proposed system provides personalization multimedia services to individual user according to each user's information recorded in database.
Furthermore, since the location of user can be predicted, the location information can be used to implement seamless personalization multimedia service. User can get personalization multimedia service in induction environment anywhere. In other words, the multimedia service needn’t to be cancelled or restarted even user moves.
By using the proposed system, user can get personal service according to user needs, instead of general unfiltered services. By using RSSI signal to process mobility prediction, system prediction accuracy of user move location can be increased. System can command next region multimedia player or device to preload data related user tag before user moving to next region.

並列關鍵字

RFID ； Mobility Prediction ； Multimedia services

參考文獻

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