多輸入多輸出干擾通道能有效允許多使用者傳收，進而增加整體網路資料傳
輸率。傳統設計上藉由干擾對齊技術，在傳送端設計預編碼器，使的接收端可將
干擾信號集中在低維度之信號空間上，因此信號可以在其它信號空間上傳輸，而
不至讓使用者互相干擾。然而，傳統干擾對齊技術在穩定通道容易有可行解的問
題，因此，有別於干擾對齊概念，另一種方式可利用晶格式編碼對齊方式，產生
結構式干擾空間，藉以解調信號。然而不論是干擾對齊，或是晶格編碼方式都需
要所有使用者下鏈通道訊息，於實際系統中傳送端無法求得完美通道訊息。因此
在本篇論文中，我們將針對傳送端只知道不完美通道下，探討晶格編碼機制下，
強韌式前置編碼設計。利用不完美通道，適當地優化前置編碼器，解調器與干擾
空間結構，使的整體通道容量最大，由於所描述的最佳化問題包含整數與非整數
優化問題，因此我們提出一種低複雜度之疊代方式，尋找其次佳解。模擬結果驗
證強韌性設計確實可以減少系統因不完美通道所造成的影響。

Multiple-input multiple-output (MIMO) interference channels (IC) have been
developed to allow the concurrent transmission between the multiple transceiver pairs.
It is therefore gains higher overall channel capacity. The conventional method to avoid
the interference at the receiver is to utilize the interference alignment (IA) technique
which can map the interference into a lower dimension space and the intended signals
are transmitted over the interference-free signal space. However, the conventional IA
encounters the feasibility problem in optimizing the precoders in quasi-static MIMO
channels. Therefore, without using the concept of IA, the alternative method is to adopt
the lattice alignment method, which can make structured interference space and
facilitates the detection of the desired signals. Nevertheless, the perfect channel state
information (CSI) is required for the above-mentioned. It is not practically to obtain the
perfect CSI in real wireless systems, especially for the transmitters. In this thesis, we
study the robust precoder design in the lattice alignment system with imperfect CSI. The
robust precoder is devised by optimizing the precoders, the decoders, and the structured
interference space, which is inherent a mixed integer and continuous optimization. The
optimum solution is therefore difficult to be solved. Therefore, we herein propose a
low-complexity iterative approach to obtain the local optimum solution. Simulations
verify our robust design.

論文審定書…………………………………………………………………………....... i
誌謝……………………………………………………………………………………...ii
中文摘要…………………………………………………..…………………….…….. iii
英文摘要………………………………………………………...…………………...... iv
目錄…………………………………………………………………………………...... v
圖次………………………………………………….………………………………….vi
表次………………………………..…………………………………………..……….vii
第一章 序言………………………………………...……......................................1
第二章 系統模型…………………………...………………………………………......8
第2.1節 多輸入多輸出干擾通道………………………...…………......………...….8
第2.2節 晶格編碼................................................................................................9
第三章 強韌式晶格對齊…………………….…..………..………………..…………14
第3.1節 傳送端編碼……….………………….………………............………..….14
第3.2節 不完美通道下的晶格對齊………………..…………………....……...….15
第3.3節 最佳化問題描述…………………..…………………………………....….17
第四章 系統模擬及探討………………………...………………………………….…19
第五章 結論與未來展望……………….......................……………………………...23
參考文獻………………………………………………………………………………..24
附錄A…………………………………………………………………………………...28

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