在EPC第一類第二代RFID系統中，標籤反向散射訊號依賴讀取器所發射的能量，因此一般標籤訊號強度小於讀取器訊號強度。所以要將標籤微弱的反向散射訊號正確的解出為設計讀取器的重點。
本論文對於第一類第二代RFID系統使用米勒編碼的標籤反向散射訊號比較兩種解調方法，匹配濾波器與轉態偵測的效能。
模擬結果顯示匹配濾波器解調效能皆優於轉態偵測。考慮理想方波訊號源時，在位元錯誤率等於 ，前者優於後者約6dB的訊雜比值；然而考慮有限頻寬訊號源時，兩者解調效能相差約4dB。
本論文也在軟體無線電上面實現符合M4米勒編碼格式標籤反向散射訊號的解調器以驗證所提解調方法的效能。
實驗結果與模擬結果趨勢相似，於訊雜比為10.5dB時，對於RN16標籤訊號解調成功率，匹配濾波器的成功率為75.67%而轉態偵測為35.43%，匹配濾波器解調效能為轉態偵測的2.1倍。

In an EPC Class1Generation2 (C1G2) RFID system, tag backscatter signal relies on the power from a reader, so the power of tag backscatter signal is very weak in general. Thus, the challenge of reader design is to demodulate of the weak tag backscatter signal correctly.
This work compares two demodulation methods, matched filter and transition detection, for the tag backscatter signal with Miller coding in a C1G2 RFID system.
Simulation results show that matched filter method outperforms transition detection. With ideal square wave sources, the former one outperforms the latter one in terms of signal-to-noise ratio (SNR) about 6dB difference at bit error rate (BER) level. However for band-limited signal source the gap reduces to 4dB.
This work also includes demodulator implementation for M4-Miller coded tag backscatter signal on a software defined radio platform to verify performances of corresponding methods.
Experiment results are similar to the simulation results. When SNR equals to 10.5dB, the successful RN16 backscatter signal demodulation rate of matched filter is 75.67%, and which of transition detection is 35.43%. The former one is 2.1 times higher than the latter.

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