FDD方式下的自適應調(diào)制的研究
Adaptive Modulation in FDD Communications over a Fading Channel
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摘要: 論文主要針對在頻分雙工(FDD)方式下的自適應調(diào)制方式進行了研究，提出了自適應調(diào)制的結(jié)構(gòu)框圖，并對反饋的上下行鏈路的包結(jié)構(gòu)進行了闡述。分析了多普勒頻移和包時間長度的乘積對系統(tǒng)參數(shù)選擇的影響，提出了迭代的自適應調(diào)制方式，即在不同的乘積范圍內(nèi)，選擇不同的模式控制發(fā)送調(diào)制方式。仿真結(jié)果表明了在不同的乘積范圍內(nèi)，選擇不同模式可以獲得最大的頻譜效率，而且系統(tǒng)的頻譜效率是隨著該乘積的增加而逐漸降低的。
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關(guān)鍵詞:
- 自適應調(diào)制; 頻分雙工; 信道預測; 頻譜效率
Abstract: In this paper adaptive modulation in Frequency Division Duplexing(FDD)communications over a fading channel is studied and packet structure and structure of adaptive modulation are proposed. Further, influence of multiplication of Doppler frequency and packet length is analyzed. Iterative modulation scheme is proposed which adjusts modulation scheme according to different multiplication. Simulation results show that in different multiplication region, different mode can get maximum spectrum efficiency and spectrum efficiency decreases with the increase of multiplication. -
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