臺灣大學: 電信工程學研究所葉丙成姜哲雄Jiang, Jhe-SyongJhe-SyongJiang2013-03-272018-07-052013-03-272018-07-052012http://ntur.lib.ntu.edu.tw//handle/246246/252655在無線環境中，適應性調變編碼(AMC) 是達到更好的傳輸效率的有效方法。同時，接收端必須反饋通道資訊(CSI) 至傳輸端以供適應性演算法使用。目前已有很多適應性調變編碼研究， 著力於如何更有效率的使用通道及回傳通道資訊給傳輸端。然而，頻繁的回傳通道資訊在某些系統中很難達成。在這篇論文中，我們提出了一個新的適應性調變編碼演算法用以減低接收端的反饋頻率。此研究中使用有限狀態的馬可夫鏈(FSMC) 來建立通道以及當前系統狀態的模型。基於此，我們可以減低反饋頻率並最大化整體的傳輸效率。此外，我們也推導了在通道預測及有限通道資訊反饋下的幀錯誤率(FER) 閉合型式解。除了根據通道資訊調整調變編碼外， 我們也提供了根據通道資訊以及幀錯誤率調整調變編碼的演算法。數值結果顯示提出的演算法的平均傳輸效率與固定的調變編碼比較， 效能顯著提升了，並且同時降低了通道資訊的反饋量。In wireless environment, adaptive modulation and coding (AMC) is a useful way to achieve better transmission throughput. At the same time, the receiver has to feed back some channel state information (CSI) to the transmitter for the adaptation. There have been plenty of works on AMC, which exploit the bandwidth more efficiently with the CSI feedback to the transmitter. However, frequent CSI feedback is not desired in some systems. In this thesis, a novel AMC algorithm is proposed to reduce the feedback frequency of the CSI. This work uses finite-state Markov chain (FSMC) to model the channel condition and the current modulation and coding. Based on the FSMC, we can reduce the feedback load while maximizing the overall throughput. In addition, the close-form of the frame error rate (FER) is derived based on channel prediction and limited CSI feedback. Instead of switching modulation and coding according to the CSI, we also provide methods to combine both CSI and FER as the switching parameter. Numerical results illustrate that the average throughput of the proposed algorithm has significant performance improvement over fixed modulation and coding while the CSI feedback being largely reduced.140 bytestext/htmlen-US適應性調變編碼預測AMCPredictionthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/252655/1/index.html