多重輸入輸出之干擾廣播通道下之干擾對齊演算法之研究

Interference Alignment Transceiver Designs for Multiple-Input-Multiple-Output Interfering Broadcast Channels

周柏均(Po-Chun Chou)

指導教授 ： 陳喬恩

國立中正大學/工學院/通訊工程學系/碩士(2013年)

摘要

蜂巢式下行通訊系統中各基地台同時傳送信號至服務細胞內的多個手機用戶，此種通道環境被稱為干擾廣播通道 (Interfering Broadcast Channels, IBC)。在此系統中，每一個手機用戶所接收到的信號除了所欲收到信號之外，還包含了異細胞間干擾與同細胞用戶間干擾，因此需要透過適當的預編碼與等化技術將干擾作抑制。干擾對齊(Interference Alignment, IA)是一種有效減輕不同用戶間干擾的技術，有著能使系統達最大自由度(Degree of Freedom, DOF)之優點，因此近年來是非常熱門的研究課題。
本論文針對多重輸入多重輸出干擾廣播通道下之干擾對齊技術進行探討。提出以洩漏能量最小化之遞迴設計，以及以秩數限制與秩數最小化為設計原理的傳送接收機架構，並利用注水理論對於所設計出之系統進一步地最佳化各子通道間的功率分配以改善干擾對齊演算法在中低訊噪比下的和率表現。最後，我們以電腦模擬對於所提出之演算法進行比較與討論。

關鍵字

廣播干擾通道 ； 多細胞 ； 干擾對齊 ； 多重輸入輸出 ； 半正定放鬆

並列摘要

In multi-cell downlink communication systems, every base station simultaneously transmits the signals to all the mobile stations within the same cell. This channel is also known as the interfering broadcast channel (IBC) . In IBC, each mobile user not only receives its intended signal but also the inter-cell-interference as well as the inter-user-interference, and therefore proper precoding and equalization techniques have to be developed for effective interference suppression.
Interference alignment (IA) is a recent developed signal processing technique which not only effectively mitigates the interference but also achieves the largest possible degrees-of-freedom in the system, and hence has been a very hot research topic over the last few years. In this paper, we investigate IA technique for the multiple-input-multiple-output (MIMO) IBC. We proposed two different transceiver designs based on the concept of leakage minimization and rank-constraint-rank-minimization (RCRM), respectivley. The proposed designs are further enhanced by performing power allocation using water-filling. The performances of the proposed designs have been verified and compared via extensive computer simulations.

並列關鍵字

Interference Broadcast Channel ； Multi-Cell ； Interference Alignment ； MIMO ； Semidefinite Relaxation

參考文獻

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