本篇論文使用多載波概念提出一個增強型的被動式標籤原型，此原型是透過一個額外電池輔助電路(battery assisted tag, BAC)提供部分能量給一個EPCglobal Class1 Gen2(C1G2)標籤，藉此延長其讀取範圍。電池輔助電路主要是用來產生一個低功率的無調變連續波，其輸出頻率位於第二代EPC所規範的操作頻率之外，以提供額外能量給標籤。本論文使用安捷倫Advanced Design System（ADS）軟體模擬增強型被動式標籤，驗證標籤晶片(IC)可同時獲取讀取器與電池輔助電路之能量，而實驗結果證明當讀取器傳送相同功率時，增強型被動式標籤可比C1G2標籤讀取範圍更遠，且在多重路徑衰減之環境中具有更好的抵抗能力。不同於半被動式標籤依靠其內部電池提供標籤晶片所需之能量，當增強型被動式標籤在電量耗盡時，仍可如同一個標準C1G2標籤依靠讀取器所傳送之射頻連續波動作。因此增強型被動式標籤裝載一個充滿電之電池，其操作模式與半被動式標籤相似，並且在電池能量耗盡時仍可如同一個標準C1G2標籤一樣動作。

This paper based on a multi-carrier method presents the design of an enhanced passive tag (EPT) that can extend the read range of an EPCglobal Class1 Gen2 (C1G2) tag by attaching a battery-assisted circuit (BAC) to the tag IC. The BAC generates a low power unmodulated continuous wave with frequency outside the tag operating band to supply additional power to the tag. In this work Agilent Advanced Design System software is used to simulate an EPT, which validates that the tag IC can harvest both signal powers from the reader and the BAC. With the same reader transmission power, empirical results demonstrate that a prototype EPT has much longer read range and is more resistant to multipath fading than a regular C1G2 tag. Unlike a semi-passive tag that depends on its local battery to work, a powerless EPT can function as a regular C1G2 tag. That is, an EPT with a charged battery behaves similarly to a semi-passive tag, and can keep working as a regular C1G2 tag after running out of its battery power.

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