在單一使用者的多輸入多輸出(MIMO)系統中，時空區塊碼(STBC)因為能夠達到最大分集增益和低解碼複雜度而成為一強而有力的技術。然而，在多重存取的多輸入多輸出系統中，最佳的最大概似接收器(ML)的結構複雜度將大幅提高。基於此因素，一些次佳但是較簡單的線性接收器因而陸續發展。
因為時空區塊碼模型和陣列處理訊號之間的相似性，使得多使用者的最小變異數線性接收器(MV)能加以應用。此最小變異數接收器結合時空區塊碼解碼和多重存取干擾抑制(MAI)。最小變異數接收器設計原理是將接收器輸出功率最小化，並且加上限制條件保持目標用戶的信號不失真。更進一步地，另一個零化限制消除了由於多天線造成的自我干擾。然而，最小變異數接收器需要反矩陣的計算。因此為了降低計算複雜度，我們提出以遞迴方式來計算反矩陣，因而減少複雜度和較佳的效能表現。

Space-time block coding (STBC) is a powerful technique because it can achieve a full diversity gain with low decoding complexity in the single-user multiple-input multiple-output (MIMO) system. However, in the multi-access MIMO system the optimal maximum likelihood (ML)receiver has a much more complicated structure. For this reason, suboptimal but simpler linear receivers have been developed for the multi-access MIMO.
Because there is a similarity between the basic STBC model and models used in array processing, we can apply this to develop multi-user minimum variance (MV) linear receivers. This MV receiver combines STBC decoding and multi-access interference suppression. The basic principle of the MV receiver is by minimizing the output power under the constraint that the symbols of the user-of-interest are kept distortionless. Further, another zero-forcing constraint results in the reduction of the self-interference due to multiple antennas. However, the MV receiver requires the calculation of the inverse of the covariance matrix. To reduce the computational complexity, we propose a scheme that computes the inverse of the covariance matrix recursively, which reduces the complexity and results in better performances.

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