此篇論文主要是基於觀察半正定放寬多天線系統，在低天線數的情形下，不能達成完全的分級增益(full diversity gain)；而晶格正交輔助之偵測方法，在低天線數的情形下則可以達成完全分級增益，惟不同的量化方法亦會影響晶格正交輔助之偵測方法的錯誤率。這篇論文主要是將晶格正交輔助應用於半正定放寬多天線系統上，並採用表列量化降低晶格正交輔助的量化錯誤率。我們使用內點法(interior-point method)來實現半正定放寬系統，並利用提前終止(early termination)的條件，更進一步降低實現半正定放寬系統的複雜度。模擬與分析結果顯示，採用晶格正交輔助之半正定放寬多天線訊號偵測不但可以達成完全分級增益，更能減少內點法的反覆運算次數，因此可以減少半正定放寬的運算複雜度。此外，我們提出的近鄰取樣表列量化方法，也可在不犧牲錯誤率的情形下，有效的降低運算複雜度。

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