在同調環境下的二維可適性陣列多重波束成型技術

Two-Dimensional Adaptive Array Beamforming with Multiple-Beam Constraints under Coherent Environments

李勇漢(Yung-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(2004年)

https://doi.org/10.6342/NTU.2004.01990

摘要

可適性天線陣列除了將想要信號接收下來，且能夠有效的將干擾信號消除，並減低雜訊成份。在實際的通訊系統中常因多重路徑效應造成同調情形產生。同調干擾信號會造成信號抵銷現象，使得波束成型器失敗。本論文中探討如何在傳統一維天線陣列架構與二維天線陣列架構下解決同調問題。我們也提出在二維可適性陣列波束成型技術下使用廣義旁辦消除器，並探討信號同調問題。
本論文使用三種修正法解決同調問題。在一維天線陣列下，分別是空間平均法、權重式空間平均法和ITAM配合一階微分限制法（DITAM）。在二維天線陣列下，分別是二維空間平均法、二維權重式空間平均法和二維ITAM配合一階微分限制法（2D-DITAM）。
在二維廣義旁辦消除器中，我們有完整說明如何在二維天線陣列下實現此架構，並提出實用且有效的二維阻隔矩陣設計方法，同樣使用二維空間平均法、二維權重式空間平均法和二維ITAM配合一階微分限制法解決在二維廣義旁辦消除器中的信號同調問題。
論文三、四章中，在傳統一維與二維天線陣列架構下的同調問題修正法，分別以ITAM配合一階微分限制法和二維ITAM配合一階微分限制法能達到最好修正效果。在第五章，二維廣義旁辦消除器中的信號同調問題也是以二維ITAM配合一階微分限制法能達到做好修正效果。

關鍵字

可適性波束成型技術 ； 多重波束限制 ； 廣義旁辦消除器 ； 同調.

並列摘要

The adaptive antenna system can receive not only the signals you are anxious for, but also effectively suppress interfering signals and noise. When it comes to practical communication system, coherence is usually generated under the circumstances of multi-path . Moreover, coherent interfering signals are likely to make signal cancellation phenomena and turn the beamforming failed. In this thesis, therefore, we would like to deal with how to solve that kind of problem on the basis of one-dimensional antenna array structure and two-dimensional antenna array structure respectively.

In addition, three methods are also applied to the improvement of the coherence problem in this paper, which inclusive of spatial smoothing method, weighted spatial smoothing method and DITAM method in the case of one-dimensional antenna array structure, while in the case of two-dimensional antenna array, two-dimensional spatial smoothing method, two-dimensional weighted smoothing method and 2D-DITAM method are also discussed.

In two-dimensional generalized sidelobe canceller(2D-GSC), we have completely described how to realize this structure and we propose a practical and effective method to construct two-dimensional block matrix. We use two-dimensional spatial smoothing method、two-dimensional weighted spatial smoothing method and 2D-DITAM method to solve the coherence problem in the 2D-GSC structure.

In chapter 3 and chapter 4, we use DITAM and 2D-DITAM to solve the coherence problems, which have been thought of as the most effective ways under conventional one-dimensional and two-dimensional antenna array. While under 2D-GSC, 2D-DITAM serves as the cure for coherence problem, which will be discussed in chapter 5.

並列關鍵字

Adaptive Beamforming ； Multiple Beam Constraint ； Coherence. ； Generalized Sidelobe Canceller

參考文獻

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