本論文電路為雙頻段15位元CMOS被動式UHF RFID Tag，應用面鎖定於室內空間定位系統-倉儲管理。雙頻段為power link 925/866 MHz以及data link 433 MHz。本tag屬被動式，電源藉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ID時使用，至於data link頻段除了先乘載經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；貨品上tag距離周遭reader或近或遠，因此本tag主要特色為寬讀取功率範圍。其中最高讀取功率上限，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，首先取代穩壓器的是低功耗的二級limiter；其中第二級limiter輸入端可接受寬範圍電壓，並輸出穩定的電壓。至於取代震盪器是利用data link傳送tag所需的時脈訊號；當data link傳送完ID，繼續利用此頻段乘載連續方波訊號，envelope detector會將之解調成時脈訊號，供後方數位電路使用。另一特色是使用多級Dickson rectifier，經模擬與量測發現，級數較多的倍壓器較易和天線端做匹配；如此可減少使用SMD匹配元件，讓RF訊號能真正被tag吸收；進而拉長tag可被讀取距離。實際量測power link於925 MHz時，最低讀取功率為-23.02 dBm、最高讀取功率為18.7 dBm，而data link最低讀取功為-41.2 dBm、最高讀取功率為14.2 dBm。本論文利用台灣積體電路(TSMC) 0.18um mixed signal/RF 1P6M CMOS製程實現。

This thesis presents a dual-band CMOS 15-bit passive UHF RFID tag chip. The tag is applied in the UHF RFID indoor localization system. Our design employs dual-band communication links that include the power link (925/866MHz) and the data link (433MHz). Because the tag is passive, the energy required by the tag is collected by energy harvesting. The power link uses continuous wave to charge the capacitance and backscatters the FM0-encoded ID. The data link transmits the OOK-modulated PIE-encoded ID to the tag first and provides the OOK-modulated square wave to the tag as the clock signal later.
In the real application, the tag can be either far away or be close to the reader, so the tag has to be sensitive and sturdy enough to the wide input power range. Hence, the tag has been carefully designed especially for the case of high input power. Also, the tag employs two stages of limiters to replace the bandgap reference circuit. Another critical characteristic of the tag is that we use a multi-stage voltage doublers in the charge pump. This makes matching between the tag and the antenna relatively easy. The power link’s power range can achieve -23.02 dBm~ 18.7 dBm. The data link’s power range can achieve -41.2 dBm ~ 14.2 dBm. The proposed RFID tag is fabricated in TSMC 0.18um mixed signal/RF 1P6M CMOS process.

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