隨著數位調變技術的蓬勃發展，數位化的產品逐漸充斥於日常生活中，如網際網路的多媒體服務、數位電視…等等，其中數位廣播(Digital Audio Broadcasting；DAB)就是繼AM、FM之後的第三代廣播系統。
目前國際上已開播或試播Eureka-147數位廣播系統的國家(包含台灣)眾多，惟與現行的AM/FM系統並不相容，需重新申請新的頻帶。美國IBOC(In-Band On-Channel)系統則主要由美國iBiquity數位公司研究開發。2002年10月美國FCC正式通過IBOC數位廣播規範為美國地面數位AM/FM廣播標準，並改稱為HD Radio。HD Radio系統主要是利用原本AM/FM的頻帶傳送數位訊號，故數位訊號的發射功率必須較現有類比訊號低上許多，以避免干擾現有類比訊號，其優點為和AM/FM系統完全相容，基本上不須另外分配頻帶。
本論文探討HD Radio AM系統的接收機設計技術，包含：訊號同步、類比/數位訊號同頻干擾消除、通道估測及等化。雖然許多文獻已探討相關訊號處理技術，但我們以簡單性及效能兩個重點，來做為評估方向，尋找 HD Radio AM系統合適的接收訊號處理技術。

With the development of digital modulation technology, the Digital Audio Broadcasting (DAB) is the third generation of broadcasting system after AM and FM.
At present, there are many countries (include Taiwan) have broadcasted the digital broadcasting system named Eureka-147. However, the system is incompatible with the current AM and FM system, it needs to apply for a new frequency band. In U.S., the IBOC digital broadcasting system mainly be studied and developed by the iBiquity company. In October 2002, FCC formally passed IBOC system as the terrestrial digital broadcasting standard and renamed as HD Radio. HD Radio system mainly transmits the digital signal by original frequency band of AM and FM. Therefore, it is no need to assign an addtional frequency band. In order to avoid interference with the existing analog signal, the transmission power of the digital signal must less than the original analog signal. Its advantage is totally compatible for the original AM and FM system.
In this thesis, we consider the receiver designing technique of HD Radio AM system, include：signal synchronization, cancellation of interference between analog and digital signal, channel estimation and equalization. Although a lot of technologies had already been discussed in many literatures, but we focus on simplicity and efficiency these two points as our main considerations, and do research on the suitable receiver architecture for HD Radio AM system. Finally, we implement the algorithm by using FPGA.

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