近年來，一個被使用在無線通訊上的多輸入多輸出位元交錯編碼
調變系統 ( MIMO-BICM ) 被蓬勃地發展來對抗多輸入多輸出衰落通
道所造成的效能損失。在這篇論文中，我們藉由設計一個特殊的交錯
復用器 ( interleaver ) 用於多輸入多輸出位元交錯編碼調變系統
並且搭配一個迭代解碼的解碼-檢測-通道估測演算法來達到具有快
速收歛之多輸入多輸出位元交錯編碼調變系統。此外通道估測在實際
應用中是一個很重要的議題。在所提出的多輸入多輸出位元交錯編碼
調變系統上，通道估測器是一個迭代估測的通道估測器，採用期望值
最大化演算法 ( EM algorithm ) 來搭配多輸入多輸出位元交錯編碼
調變系統。因為所提出之交錯復用器具有特殊的架構，我們運用所提
出的解碼-檢測-通道估測演算法，一個軟性輸出的通道解碼器
( SISO MAP channel decoder ) 會立即回饋通道編碼的軟訊息給軟
性干擾去除之最小平方檢測器 ( MMSE-SC detector ) 以及通道估測
器在一個已被接收的通道解碼滑動視窗時間長度。然後在同一個迭代
解碼以內，被回饋的通道編碼軟訊息可以立即被軟性干擾去除之最小
平方檢測器和通道估測器所有效使用來增進整體迭代解碼之效能。
使用在無線通訊上的多輸入多輸出位元交錯編碼調變系統被蓬勃地發展來對抗多輸入多輸出衰落通道所造成的效能損失。因此被提出的多輸入多輸出位元交錯編碼調變系統在錯誤率效能比傳統的多輸入多輸出位元交錯編碼調變系統擁有更快的收斂速度。

MIMO-BICM(Multi-input multi-output bit interleaved coded modulation) systems have been investigated prosperously in wireless communications. In this thesis, we propose a fast-convergence MIMO-BICM scheme with the EM (expectation-maximization) based channel estimation by designing
the bit interleaver and the iterative decoding-detection-estimation algorithm. Since the specific structure of the proposed interleaver, the softoutput of the decoder can be fed back to the MMSE-SC (minimum mean square error with soft cancelation) detector and the estimator after a window
length and then the detector and the channel estimator can immediately use these soft values within the same iteration. Hence, the proposed MIMOBICM scheme can achieve a faster speed of convergence as compared to the
conventional MIMO-BICM scheme.

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