在本篇論文中，我們將提出一個新式使用於無線辨識系統且結合消除干擾技術的防碰撞演算法：延展劃分選擇時槽式演算法，且此方式包含先進多重存取方法:被動式分功率多重存取系統來增強辨識效率。我們使用訊號處理與訊號通訊的方式增強防碰撞演算法的效能。此方法相較於目前現有演算法有不同之觀點。
在系統的效能分析中，我們觀察到造成現今系統辨識率無法突破指標參考之值1/e的主要原因為讀取機無法辨識在碰撞中的標籤信號，因此為能夠有效率改善辨識率我們使用消除干擾技術且配合分功率多重存取系統，使其信號有功率上的差異度來增加成功偵測信號的機率。而在被動式分功率多重存取系統中我們將在讀取器範圍內的標籤依據接收到不同的讀取器信號功率大小可劃分為多個群組，以此方式能增強消除干擾技術偵測能力。因此延展劃分選擇時槽式演算法能有快速且高效率的辨識率。模擬將針對不同的標籤數目等變數進行分析，此外也在相同數目的標籤進行與現有的演算法比較，而模擬結果也呈現優秀的辨識率。

In this thesis, we propose a new anti-collision algorithm: Spread Partial-Q Slot-Count (SPSC) algorithm which contains a novel multiple access method, Passive power division multiple access (Passive-PDMA) systems for Radio Frequency Identification (RIFD) systems to enhance identification rate. We use the way of “Signal Processing” and “Signal Communication” to improve the performance of the anti-collision algorithm. It has different aspects with existing anti-collision algorithms now.
We observe that the throughput of the present anti-collision algorithms in RFID systems is still below the reference value 1/e since the reader can not identify tag’s packets in tag-collisions. In order to improve throughput efficiently, we adopt interference cancellation schemes and intentionally introduce disparate power level into tags in Passive-PDMA systems to enhance the detection of a tag’s signal in the tag-collision. In Passive-PDMA systems, we partition tags into multiple groups with different power levels according the received power level of the reader to enhance the detection ability of interference cancellation. Thus, SPSC algorithm enables the faster identification and yields much higher throughput.
In this work, we analyze the performance of SPSC algorithm with various numbers of tags, and compare with some existing anti-collision algorithm. Simulation results validate the excellent features of SPSC algorithm.

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