本論文電路為基於極簡化EPC global Class-1 Generation-2 UHF RFID Protocol所設計的雙頻段一次性可編程15位元CMOS被動式UHF RFID Tag，應用於被動感測器。雙頻段為Power Link 925/866MHz以及Data Link 433MHz。Tag包含射頻/類比前端電路、基頻處理器以及一次性可編程電路。本論文Tag屬於被動式，電源藉由energy harvesting產生；而Power Link頻段負責傳送連續弦波訊號，經charge pump對電容充電以提供電源。此外，Power Link頻段也供Tag反散射資料時使用。至於Data Link頻段除了先承載經Reader編碼與調變的ID，還會再傳輸連續方波訊號，當作給Tag所需之時脈使用。
考量實際應用狀況，感測物品上的Tag距離周遭Reader可能或遠或近，且周遭環境中的Tag數量也可能不只有一個，因此本論文RFID Tag的主要特色除了能夠正確比對Tag ID並回傳資料之外，也有能讓Reader逐一辨識Tag以及防止多個Tag回傳時發生碰撞的功能。如本論文中第一個指令的功能為計數後8位元的ID後再依序回傳，就是一個簡單的防碰撞回傳機制。而最高讀取功率上限，是藉著特殊設計的放電機制達成。其它特色如無穩壓器和無震盪器，而取代震盪器是利用Data Link傳送Tag所需的時脈訊號。當Data Link傳送完Preamble、Command和ID後，繼續利用此頻段承載連續方波訊號，envelope detector會將之解調成時脈訊號，供後方數位電路使用。本論文所述晶片是利用台灣積體電路(TSMC) 0.18um CMOS製程實現。

In this work, we design a dual-band 15-bit CMOS passive UHF RFID Tag based on simplifying the EPC global Class-1 Generation-2 UHF RFID Protocol. Our design employs dual-band communication links that include the power link (925/866MHz) and data link (433MHz). This work comprises RF/analog frontend circuits, a baseband processor and a one-time programmable memory circuit. Because the tag is passive, the energy required by the tag is collected by energy harvesting. The power link uses continuous wave to change the capacitance and backscatters the FM0-encoded data. The data link transmits the OOK-modulated PIE-encoded data to the tag first and provides the OOK-modulated square wave to the tag as the clock signal for the tag later.
In the real application, the tag can be either far away or be close to the reader, and the number of tags in the environment may be more than one. Therefore, the main feature of the RFID tag in this thesis is the ability to correctly compare the Tag ID and return the data. In addition, there is also a function that allows the Reader to identify tags one by one and prevent collisions when multiple tags backscatter their data. The proposed RFID tag is fabricated in TSMC 0.18um CMOS process.

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