在本計劃中，第一年我們針對多重輸出入正交分頻多工系統下設計最佳效能 之時空頻三維碼，所得的時空頻三維碼可在空間、時域、頻域獲得最佳分集增益 以提升系統傳輸品質；同時我們也提出低搜尋複雜度的次佳效能之時空頻三維 碼。此外，在高效能時空頻三維碼的基礎下，融合降低峰均功率比技術之概念，
設計出低峰均功率比時空頻三維碼。從模擬中可以觀察得到，我們所提出的時空 頻三維碼效能比文獻中所提出之碼更好；在多延遲路徑情況下，時空頻三維碼可 以得到頻域上之分集增益，隨延遲路徑增加位元錯誤率降低，而在延遲時間的比 較上，時空頻三維碼的效能隨延遲時間拉長而增加。我們提出的低峰均功率比時 空頻三維碼，在子載波數為 64 及機率10−5的情況下就有將近 4dB 的降低量，同 時我們的降低效果和選擇性映射方法使用 8 個候選序列的情況相近，但選擇性映 射使用 8 個候選序列的情況會造成系統的複雜度增加很大，而我們的方法不會增 加複雜度。另外，我們在降低峰均功率比的同時也保證我們的錯誤率不會變差。
若系統要求極低的峰均功率比，可以將我們提出的方法加上以往的降低方法來達 到這樣的要求，由模擬也可以看到這樣做是有效果而且可行的。
在第二年的計劃裡，我們將第一年計劃設計完成的低峰均功率比時空頻三維 碼做為基礎並與低密度位元檢測碼結合，整合設計出時空頻三維低密度位元檢測 碼。整合設計後的效能比時空頻三維碼大幅提升許多，並且可隨解碼疊代次數增 加而有更好的效果。同時，我們將設計的時空頻低密度位元檢測碼與目前最佳的 低密度位元檢測碼串接時空頻碼的效能相比，也都有更好的效能表現。此外，在 不同接收天線的環境下也都有效能改善的情況。最後，由模擬結果可說明此時空 頻低密度位元檢測碼適合於高速無線多媒體傳輸之通道編碼系統。
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