在資訊交換快速的時代裡，無線通訊系統的便利性儼然已經使其成為人們互通有無的主流方式，而其中多天線(Multi-Input Multi-Output, MIMO)無線傳輸系統更是被公認為能有效增加傳輸速率以及改善無線傳輸錯誤率的資料傳輸方式。然而以空氣為傳輸媒介而非以傳輸線等單一媒介的無線傳輸方式卻也同時帶來了不同使用者間的訊號互相干擾。因此如何減少使用者間的互相干擾、有效率的利用傳輸通道為此篇論文的主要研究方向。
當第二使用者(cognitive radio user)在傳輸訊號前察覺傳輸頻帶上已有其他高優先性使用者(primary user)正在佔用同樣的頻帶時，為了不影響其他使用者，可以選擇暫停傳輸，然而在此篇論文裡，我們提出在多天線的傳輸系統裡，根據多路徑傳輸角度估測之隱匿式感知無線電波束成形技術可以使第二使用者在不影響高優先性使用者的前提下考慮空間使用程度使其同時達到良好的傳輸品質。即第二使用者考慮高優先性使用者訊號接收與傳送路徑的角度，以時間、頻率、空間等資訊有效率的估計訊號入射角度(DOA estimation)且入射角度數目甚至能多於天線數目，分配傳輸能量降低對主要使用者的干擾同時最佳化傳輸品質。

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