考慮多輸入多輸出無線通訊系統通道容量之天線陣列最佳化

Optimization of antenna arrays for the channel capacity of MIMO wireless communication systems

李佳翰(Jia-Han Lee)

指導教授 ： 李枝宏

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2013年)

https://doi.org/10.6342/NTU.2013.10024

摘要

隨著行動通訊的發展，個人通訊需求以及多媒體資訊交流的急遽增加，因此如何在有限頻寬內取得較佳的頻譜使用率和傳輸品質，逐漸成為重要的問題。在多輸入多輸出無線通訊系統中，因衰落通道獨立的特性，利用空間分集及空間多工技術來提高傳輸品質及速率，然而卻無法避免天線陣列間的空間相關性會造成通道間不再獨立，使得傳輸效能受到影響。由於現今行動裝置微型化的趨勢，造成天線間距越來越小，產生了交互耦合效應，使得通道容量值增加。因此首先介紹二維入射、三維入射環境下之空間相關性和天線陣列間交互耦合效應，並推導出通道容量式，藉以判斷各天線陣列效能的優劣。接著介紹混合型混亂粒子群最佳化演算法，並應用至天線陣列最佳化，尋找出在不同的信號入射環境下，通道容量值最佳的天線陣列。實驗模擬全相關二維信號入射、三維信號入射的不同環境下以及考慮交互耦合效應時，在限制搜索範圍內尋找最大通道容量值之二維、三維最佳化天線陣列，並比較均勻與非均勻天線陣列分佈和效能。最後則討論空間相關性和交互耦合效應對於通道容量值的影響。

關鍵字

無線通訊 ； 通道容量 ； 天線陣列 ； 最佳化

並列摘要

Along with the development of mobile communications, necessity and exchangeability of multimedia information of personal communication rapidly increase. Study to improve to achieve a better spectral efficiency and transmission quality within the limited bandwidth has become an important issue. In MIMO wireless communication systems, the techniques of spatial diversity and spatial multiplexing make both quality and rate ameliorate in transmission. However , the spatial correlation between the elements of antenna array significantly affects spectral efficiency and transmission quality. Miniaturization trend of mobile devices makes antenna spacing become even smaller than before, leading out the mutual coupling effect which increase channel capacity. Therefore, research of the spatial correlation, mutual coupling , and channel capacity functions under surrounding of 2-D signal arrival and 3-D signal arrival will be described first, as a valuation of efficiency. Then introduce chaotic particle swarm optimization and optimization of antenna arrays for the channel capacity. Compare the difference of using uniform antenna array and non-uniform antenna array. Present the optimal array geometry. Final,we will discuss the effect of spatial correlation and mutual coupling for channel capacity.

並列關鍵字

MIMO ； Channl capacity ； Optimization ； antenna arrays

參考文獻

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