本論文為雙頻段一次性可編程記憶體15位元CMOS被動式感測UHF RFID Tag，應用方面為室內感測系統。雙頻段為power link 925/866 MHz及data link 433 MHz。本tag屬於被動式，電源由energy harvesting產生，power link頻段傳送連續弦波訊號，由charge pump對電容充電提供電源；data link頻段除了接收reader端的preamble指令後編碼與調變ID，還需傳送連續方波訊號，當作tag所需之時脈。寫入ID功能使用一次性可編成電路，使用高壓擊穿電晶體，寫入15位元的ID。感測功能使用離散時間的一階三角積分調變器，透過輸入直流電進行調變，時脈使用data link產生的方波，輸出一個周期性訊號並由FM0傳送。
在應用上，在定位系統中增加了感測功能，可以是溫度或其他數據，本論文重點著重於極低讀取功率的RFID Tag。其他特色如參考電壓電路取代傳統band gap電路，有較低供耗，並輸出穩定電壓。至於取代震盪器是利用data link傳送Tag所需時脈訊號；當data link傳送完preamble及ID，繼續利用此頻段乘載連續方波，envelope detector將之解調為時脈訊號，供後方數位電路與DSM電路使用。實際量測power link於866MHz時，最低讀取功率為-16.30dBm，而data link最低讀取功率為-18.40dBm。本論文使用台灣積體電路(TSMC)0.18um mixed signal/RF 1P6M CMOS製成實現，由Full-Custom設計流程來完成。

Abstract
The thesis presents a dual-band one-time Programmable 15-bit CMOS passive UHF RFID Tag for indoor passive sensing applications. The dual band frequencies are 925/866 MHz for the power link and 433 MHz for the data link. Since the tag is passive, the supply voltage is provided by energy harvesting. The reader transmits a continuous wave (CW) signal through the power link channel to charge the tag. The tag employs a charge pump circuit to convert the CW energy to a dc voltage and an off-chip capacitor is used to store the charge. The reader also transmits the PIE-encoded commands as well as the clock signal for the tag through the data link channel. Since the clock is provided by the reader, the tag does not need its own oscillator. The 15-bit tag ID is written to a one-time programmable memory by using high voltage to break through the thin oxide of PMOS transistors. The tag includes a first order Delta-Sigma modulator (DSM) that can cooperate with a passive sensing device. The DSM modulates the output voltage of the sensing device into a bit stream. The tag can backscatter the bit stream to the reader so the reader can convert the bit stream to the data measured by the sensing device. The tag chip is fabricated by the TSMC’s 0.18 um CMOS process.

As for the sensitivity measurement, the measured power link sensitivity is … and the measured data link sensitivity is … The result is not satisfied at all. We conjecture that the high voltage for programming the ID damages the substrate of the tag chip. This is probably the reason why the sensitivity measurement is not as good as the simulation result

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