多入多出無線通道塑模與模擬及容量分析

Modeling ,Simulation and Capacity Analysis of MIMO wireless channels

陳彥均

指導教授 ： 黃正光

元智大學/工程學院/電機工程學系/碩士(2003年)

摘要

MIMO系統可以提升通訊可靠度及增加通道容量，但因天線配置及通道環境的關係，通道間將具有相關性使通道容量與性能下降。
因此本論文將針對相關性對通道容量等問題進行討論。首先假設在理想不相關窄頻MIMO通道的情形下，探討SIMO、MISO與MIMO系統通道容量的分佈情形，並以SVD分解之特徵值方法分析通道容量特性。
再者探討不同天線配置與空間相關性之關係，並將天線配置、入射角、角度擴散、K-factor、功率分配等因素納入真實環境相關性窄頻MIMO通道模型考量，探討不同通道參數對通道容量的影響。為了使通道模型更符合實際，除上述參數外並考慮多路徑等問題，建立寬頻通道模型，且因IEEE 802.16a深具發展潛力，進一步探討IEEE 802.16.3固定式無線通道模型可供後續研究參考之用。
無線通訊中除了通道容量外，性能分析的研討也是很重要之研究項目，因此在論文最後，將分析2I2O STBC架構與通道相關性之相關性，以利暸解通道相關性對性能之影響。

關鍵字

通道容量 ； 模擬

並列摘要

Wireless MIMO system with multiple Tx/Rx antennas can promote channel capacity and performance effectively. However, the channel fading coefficients may be for different practical environments. When the coefficients are correlated, it is shown that the channel capacity and performance will decrease.
The thesis investigates channel capacity at MIMO system models and different channel environments. At first, assume the ideal uncorrelated channel, we discuss channel capacity of SIMO、MISO、MIMO system and use eigendecomposition (SVD) method to analyze channel characteristic.
For more realistic situations we study the effect of spatial correlation between adjacent antenna elements. We take advantage of the spatial correlation characteristic to simulate MIMO channel model. We discuss channel modeling, simulation and capacity when the MIMO channel considers those physical parameters such as antenna allocation, AOA, K-factor, and power allocation for narrowband channel case. After that, we further build the wideband channel model that considers multipath effect and Doppler effect in order to model the physical propagation environments and develop a wideband correlated MIMO channel simulator. Finally we introduce the IEEE 802.16.3 Non-Los fix wireless channel model for future research.
Also included is a case study which study the BER performance of a 2I2O STBC system, under the influence of proposed correlated MIMO channel effects.

並列關鍵字

MIMO ； K factor

參考文獻

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