在本論文中，我們考慮了多天線雙向放大傳遞中繼端網路下聯合天線選擇與功率配置的問題，其中天線選擇機制可以藉由空間多樣性而有效降低射頻的設計成本。而功率配置則可以讓功率更適當的去分配在傳輸天線上。我們的目標是將多天線雙向合作式中繼端放大網路藉由天線選擇與功率配置的方式使總系統資料傳輸率最大化。為解決此複雜的問題，我們提出因式圖模型搭配和積演算法，並在所提出之軟式資訊演算法中加入了比重的因素以及使用最後軟式資訊的結果進行適當的功率分配。我們提出的軟式資訊演算法在時間複雜度上表現更好，且與無窮盡演算法結果相近。相關的電腦模擬結果顯示在不同的限制天線選擇數目或功率考量下，我們所提出的軟式資訊演算法可以接近其上限值但所需的時間卻較低。

In this thesis, we consider joint antenna selection and power allocation in multi-antenna two-way amplify and forward (AF) relay networks.
While antenna selection employs only a subset of the available antennas for data transmission/reception, this scheme can maintain the same diversity as the original systems, yet reducing the cost of radio-frequency (RF) chains. Meanwhile, power allocation can properly allocate the power to enhance the system performance. The objective of this work is to maximize the data rate of a multi-antenna two-way AF relay network with proper antennas subset selection and power allocation. To solve this complicated problem, an effective factor graph approach along with the sum and product algorithm is considered. In the soft information exchange process, ingenious devised weight factors are also addressed to speed up the converge rate. Conducted simulations show that the proposed approach is close to the optimum performance by exhaustive search and the water-filling method, yet with substantially lower complexity.

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