由於良好的頻譜使用效率以及對抗多路徑通道的能力,OFDM 系統已成為下一代無線通訊系統的主要技術。在多使用者的環境中,多存取OFDMA 系統已成為一個重要的技術並且開始被重視。為了達成好的傳輸效能,動態資源分配的方法已被引入到多使用者的通訊技術裡,但也由於使用這個方法,多用戶的 OFDM 系統將面臨比單用戶系統裡更嚴格的同步要求。在本計畫中,為達成能適合作為下一代無線行動通訊的方法,我們研究上傳鏈的 OFDMA 系統在動態資源配置的方法下,同步與通道估計的實體層技術。我們希望在多使用者的行動無線通道環境中,經由此計畫的研究能得到良好的 OFDMA 訊號處理演算法提升傳輸性能,以適合採用動態資源配置法。 Orthogonal frequency division multiplexing (OFDM) becomes the main technology for the next generation of wireless communication system since it has high spectral efficiency and is resistant to multipath channels. In a multiuser environment, the multiple access OFDM (OFDMA) system is attractive. For a better transmission performance, the resource allocation concept is introduced to the multiuser OFDM system. However, OFDMA needs more stringent synchronization requirement than the single user OFDM system. In this project, we study the synchronization and channel estimation technology in an uplink OFDMA system based on dynamic resource allocation methods in order to be suited to future wireless communication standards. We expect that this project will yield advanced communication signal processing algorithms applicable in an OFDMA system to improve transmission performance with dynamic resource allocation. 研究期間:9608 ~ 9707