近年來，半定放寬法被廣泛應用到各種研究領域上，而在多輸入多輸出檢測法應用上，當天線數增加、mapper變大的情況下，半定放寬法更被視為比球體解碼演算法要來得高效能且複雜度低，逐漸的，此方法獲得研究者的興趣和注意。邊界限制半定放寬法是一個簡單且低複雜度的偵測法，其搭配特殊的原始-對偶內點法(PD-IPM)可以達到演算法複雜度O(n3.5)。邊界限制半定放寬法最大的特性，在於mapper的大小並不影響所解問題本身的矩陣維度，所以我們利用此特性選擇了邊界限制半定放寬法當作研究的基礎。
另一方面，由於我們所制定的收發天線數目為16ˣ16，邊界半定放寬法會導致欲解的矩陣維度增大為原來的四倍，過大的矩陣會使得問題複雜難解，因此，我們提出一個修改過的邊界半定放寬法。此法利用下邊界(lower-bound)對於高階正交調幅調變(higher-QAM)影響較小的概念，將下邊界的限制式移除，使得矩陣維度約只剩邊界限制半定放寬法的一半，來降低複雜度。
我們以PD-IPM演算法解修改過的邊界限制半定放寬的問題。從效能模擬結果發現，在49dB處可以達到10-3的錯誤率，比原來的邊界限制半定放寬法損失1.5dB，不過仍符合我們所制訂的規格(<50dB at 10-3)，在運算複雜度上，此論文所提出的方法將比原來的方法省51.21%。此外，我們也針對其矩陣對稱的特性去設計整個針測器的硬體架構。另外，求解線性方程組中，我們利用重複使用同一個架構達到使用率最佳化及高吞吐量。

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