現今的被動式無線射頻系統，使用分時讀取的方式去讀取各個標籤識別碼。因為在同一時間只能讀取一個標籤，系統效能上將會比其他結合了多存取技的現代化通訊系統差。為了改善被動式無線射頻系統中的標籤讀取率，本篇論文中提出一個新的被動式無線射頻系統，結合了分頻多工和分時多工的技術。
提出的系統架構中，我們使用文獻[4]提出的多載波回傳技術，可以同時接收在不同頻帶上多標籤的回傳訊號。為了使頻帶上的同通道干擾降到最低，我們提出了細胞式配置法。又為了緊密結合分頻多工和分時多工的技術，我們也提出一個改變於原來第二代無線射頻辨識系統規範中的時槽式ALOHA演算法。此外還提出了能量分佈的規則，使系統有更好的能量消耗。
假設標籤在讀取的範圍內均勻分佈，利用分階讀取的技術將更進一步避免標籤衝突並且使系統能量消耗減到最小。模擬結果明顯的顯示出本篇論文提出來的系統改善了系統讀取效能和總能量的消耗。

The present passive Radio frequency identification (RFID) systems use a variety of time division multiple access (TDMA) techniques in individual tag identification. Because only single tag can be identified in the same time, the system performance is inferior to other modern communication systems that incorporating diverse multiple access technologies. In order to improve the tag read rate of the passive RFID system, a novel passive RFID system jointly using frequency division multiple access (FDMA) and TDMA technologies is proposed in this work.
In the proposed system, we use the multi-carrier backscattering technology proposed in [4] to receive multiple tag backscatter signals in various frequency bands simultaneously. In order to minimize the co-channel interference (CCI) in each frequency band, a cellular-based deployment is proposed. In order to seamlessly combining the FDMA and TDMA technologies, a modified slotted Aloha algorithm based on the Gen2 standard is also proposed. In addition, a guideline of system power allocation is derived to achieve better overall power consumption.
Assuming tags in the interrogator access range are uniformly distributed, a multi-stage interrogation scheme is utilized to further avoid tag collisions and minimize the system power consumption. Simulation results demonstrate distinct performance improvements of the proposed system in terms of the tag identification rate and the overall power consumption.

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