無線射頻辨識系統是一種短距離通訊系統，其使用無線電波來追蹤或辨識物品。在密集式讀取器環境下，無線射頻辨識系統效能，將會受到讀取器之間互相干擾而受到限制。為了防止互相干擾，EPCglobal提出使用將讀取器依照通道頻譜與標籤通訊，利用分頻多工擷取方法通訊，然而如何增加頻譜使用效率，能讓頻譜容納更多台讀取器，這將會是重大的挑戰。
在密集式讀取器環境下，標籤訊號使用振幅移鍵調變和米勒調變編碼，由此可知標籤訊號為雙邊帶調變，它佔用兩個通道頻寬，由於標籤雙邊帶頻譜帶有相同的資訊，若消除雙邊帶頻譜之一，使用剩下的單邊帶頻譜來解調標籤訊號，則增進頻譜使用效率。
在本論文提出一種在有限的頻寬下，有效率之新穎的通道配置方法。此方法與EPCglobal Gen2 UHF RFID標準頻率配置法相較，在密集式讀取器環境下於相同頻寬，可允許容納更多台讀取器同時工作。本論文亦提出依照通道配置方式之讀取器設計，最後並利用模擬軟體模擬與實驗量測驗證本論文提出之方法可行性。

Radio frequency identification (RFID) system is a short range communication system, which uses radio wave to identify and track objects in logistic processes. In a dense-interrogator environment, a RFID system performance is limited by reader-to-reader interference. In order to avoid reader-to-reader interference, EPCglobal Class-1 Generation-2 UHF RFID standard suggests that readers should adopt the channelization to instruct tags. Using such a frequency division access method, how to increase the spectrum efficiency to accommodate more active readers is a vital challenge.
In a dense-interrogator mode, tags backscattered signals by amplitude-shift keying (ASK) modulation and miller modulated subcarrier (MMS) encoding. The tag signal is a double-sideband (DSB) modulated signal that occupies two channels in the dense-interrogator mode. Since the two tag response channels contain the same information, discarding one sideband of the DSB signal and extracting the tag information from the remained sideband, the system spectrum efficiency can be enhanced.
In this thesis, a novel efficient channel allocation scheme is proposed, which can be very useful in many circumstances with limit spectrum resource. Compared with the channel allocation scheme in EPCglobal standard, the proposed scheme can accommodate more simultaneous active reader in a dense-interrogator environment with the same operating bandwidth. The corresponding reader for the proposed scheme is designed. Simulations and experimental results validate the feasibility of the scheme.

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