目前的被動式無線射頻辨識系統(Radio Frequency IDentification, RFID)，使用分時多工(Time division multiple access, TDMA)的方式讀取標籤識別碼。系統中之標籤碰撞問題為導致標籤讀取率降低之主因。
多載波無線射頻辨識系統(Multi-carrier RFID system)結合分頻多工(Frequency division multiple access, FDMA)與分時多工TDMA技術；其中多載波讀取器可同時接收不同頻帶上多個標籤回傳訊號。但受限於現行EPCglobal Genaration 2(以下簡稱Gen2)規範，當標籤發生碰撞時，只能取得一組標籤識別碼。
本論文中，我們推導出多載波讀取器的讀取率並利用程式模擬讀取器在不同位置的讀取率。
本論文也利用Software Define Radio(SDR)技術,實作多載波讀取器。在兩個載波發射器(carrier wave emitter)的環境中進行標籤碰撞讀取實驗，結果顯示我們能順利取得一個標籤識別碼。

The present passive Radio frequency identification (RFID) system uses time division multiple access (TDMA) techniques to acquire tag identification. The tag collision problem is a major factor results in low tag identification rates.
Multi-carrier RFID system incorporates the frequency division multiple access (FDMA) technique with the TDMA technique to enhance the tag read rate, in which a multiple-carrier reader can receive multiple tag backscatter signals in different frequency bands simultaneously. Due to current EPCglobal Class-1 Generation-2 (Gen2) standard, a reader however can receive one tag only in a tag collision.
In this thesis, we derive the tag read rate in a multi-carrier system, and verify the system throughput with simulations.
We also use Software Define Radio (SDR) to carry out a multi-carrier reader in this thesis. The tag collision experiments in an environment with two carrier wave emitters (CWE) demonstrate that the multi-carrier reader can successfully extract one tag from the collided tags.

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