在無線通訊的環境中，多路徑效應的衰減是非常嚴重的，由於多路徑效應的影響使得接收到的訊號受到了符元間之干擾，在本論文中，我們提出在多輸入多輸出(multiple input multiple output(MIMO))加入錯誤控制碼和渦輪等化器來對抗多路徑效應，我們把這機制命名為多輸入多輸出之分集渦輪等化器，簡稱為(MIMO-DTE)。

在MIMO-DTE的系統中，我們使用多根天線傳送的方式來達到空間分集(spatial diversity)，在接收端使用格式狀等化器來消除因多路徑效應多產生之符元間干擾，並且使用等化器和解碼器互相傳遞軟式資訊，經過多次交叉迭代後，可以得到較佳的系統效能。

我們也用外質資訊轉換圖(extrinsic information transfer (EXIT)) Chart預測MIMO-DTE的系統錯誤率並且分析系統的收斂行為， 利用外質資訊可描述接收端的渦輪等化器和解碼器之轉換特性，從系統中觀察到解碼軌跡可以了解迭代次數收斂情形，最後，模擬結果表示MIMO-DTE的錯誤率效能比MIMO-TE的效能來的好，從實驗結果表示預測的錯誤率是非常接近實際模擬的錯誤率。

The effect of the multi-path fading is a serious problem in a wireless communication. Due to the multi-path effect, signals that carry the message are degraded by inter-symbol interference (ISI). In this thesis, we propose a joint error control and equalization scheme under the MIMO scenario to fight the multi-path effect. We call this scheme “multiple input multiple output diversified turbo equalization” (MIMO-DTE).

In the MIMO-DTE system, we use multiple-antenna transmission to achieve spatial diversity, adopt convolutional codes for error correction, and utilize the trellis structure derived from the ISI channel to perform the equalization at the receiver. Imitating the mechanism of turbo equalization, we iteratively exchange the soft information between the trellis equalizers and the convolutional decoders. We find that the MIMO-DTE system gets improved bit error rate (BER) performance as iterations go on at first. After a few iteration however, the performance reaches convergence.

We also utilize the extrinsic information transfer (EXIT) Chart to predict the BER performance, and the convergence behavior of the MIMO-DTE system. We make use of the extrinsic information transfer chart to describe the transfer characteristics of turbo equalizer and decoder. By observing the decoding trajectory, we understood the number of iterations for reaching convergence in our system. Eventually, simulation results showed that the MIMO-DTE BERs’performances are better than that of MIMO-TE, and the experiment results also show that the predicted BERs’ were close to simulation results.

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