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系統主要特色是利用原本AM/FM的頻帶傳送數位訊號，其優點為和類比AM/FM系統完全相容，基本上不須另外分配頻帶。
本論文第一部份遵循規格書建立HD Radio AM系統實體層之傳送端與接收端軟體模擬平台，模擬通道效應以及自身帶有的類比AM訊號對數位訊號的干擾。第二部份探討相鄰電台可能對自身電台的數位訊號所造成的干擾，此干擾現象稱為adjacent channel interference或multiple access interference (MAI)。第三部份整理與比較幾種可能的MAI現象解決方法，並提出一套新的架構。經由模擬證實本人所提出之多位元流訊源編碼設計方式可有效緩和MAI產生的影響。第四部份為硬體實作，將基頻系統在Xilinx Virtex-4 FPGA驗證平台上實現。

In October 2002, the IBOC system was officially adopted as the terrestrial digital broadcasting standard by FCC (Federal Communications Commission) in the US, and renamed as “HD Radio” afterward. One of the features of HD Radio system is that Digital signals are transmitted in the conventional AM/FM frequency range. It’s an advantage that HD Radio system is totally compatible with analog AM/FM system without new spectrum allocation.
In this thesis, we establish the software simulation platform at PHY layer of the transmitter and receiver of HD Radio AM system, simultaneously considering the channel effect and the analog host AM signal interference. Then, the interference to digital signals due to adjacent broadcasting channel which is so-called “adjacent channel interference” or “multiple access interference (MAI)” is taken into account. Subsequently, we discuss and compare some conventional MAI mitigation methods and propose our schemes. By means of the simulation results, it’s proved that the proposed multi-stream source-spectral mapping schemes can decrease the impacts of MAI effectively. Finally, we realize and verify the baseband transceiver of HD Radio AM system on Xilinx Virtex-4 FPGA development platform.

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