在此論文中我們考慮K用戶多輸入單一輸出干擾通道(K-user multiple-input single-output interfer- ence channel),且我們假設所有通道為塊狀衰減(block-faded)通道。另外,我們假設接收端擁 有完整的通道資訊(channel state information)而傳送端只擁有通道分布資訊(channel distribution information)。我們也假設接收端能實現連續干擾消除(successive interference cancelation)。基 於以上假設,我們將此環境下之波束成型(beamforming)設計描述為一中斷機率(outage proba- bility)及個別傳輸功率(individual power constraint)限制下之速率效用(rate utility)最大化問題。 由於複雜的中斷機率限制,我們所考慮的問題是一個非凸優化問題(nonconvex optimization problem)。因此我們提出了一個連續凸近似(successive convex approximation)方法來快速得到一 波束成型之近似解。我們更證明了由我們提出的連續凸近似演算法產生的近似解會是原本的 波束成型設計問題之靜止點(stationary point)。為了更進一步降低演算法之複雜度,我們也提 出了分散式(decentralized)連續凸近似演算法。在此分散式演算法中每個傳送端只需局部通道 分布資訊(local channel distribution information)及來自其他傳送端的少量資訊來進行波束成型 設計。我們的模擬結果顯示出我們所提出的兩個演算法都能達到接近最佳效能(near-optimal performance)。且在接收端實現連續干擾消除的確能提升系統效能,特別是在需考慮到用戶間 的公平性時此效能提升更加明顯。

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