此篇論文提出一個低複雜度數位交叉預扭器(crossover digital predistorter, CO-DPD)，在多輸入多輸出(multiple-input multiple-output, MIMO)的系統中補償串音干擾(crosstalk)及非線性功率放大器(power amplifier, PA)所造成的訊號失真。此多輸入多輸出系統使用2×2空頻區塊編碼(space frequency block coding, SFBC)的正交分頻多工(orthogonal frequency division multiplexing, OFDM)。因為傳統交叉數位預扭器的運算複雜度相對較高，因此我們提出一個低複雜度交叉數位預扭器來降低其複雜度的問題。低複雜度數位交叉預扭器與傳統交叉數位預扭器的性能比較將會使用錯誤率(bit error rate, BER)、TD(total degradation)以及頻譜功率密度(power spectral density, PSD)。

This thesis proposes a low complexity crossover digital predistorter (CO-DPD) to compensate the non-linearity loss of a signal due to power amplifier (PA) and crosstalk interference in a multiple-input multiple-output (MIMO) system. This work applies 2×2 space frequency block coding (SFBC) for orthogonal frequency division multiplexing (OFDM) signal. Because the computational complexity of conventional CO-DPD is rather high, we propose a low complexity CO-DPD to mitigate the complexity problem. This low complexity CO-DPD has comparable performance with conventional CO-DPD. Several simulations evaluate the performance of our proposed method in bit error rate (BER), TD (total degradation) and power spectral density (PSD).

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