在以偏移正交振幅調變為基礎的濾波器組多載波系統中，多重路徑通道造成的符元間干擾與子通道間干擾對偵測器之效能通常有很大的影響，因此需要等化器以緩解干擾。本論文以基於最小均方誤差準則之線性等化器及非線性的決策回授等化器為主軸，進行等化器係數的推導及探討等化器係數性質。由於偏移正交振幅調變訊號在時間軸上為純實數符元與純虛數符元交錯的訊號，故等化器最直接的做法為對這兩類符元分別去計算等化係數。本論文利用數學證明以下結果：在最小均方誤差線性等化器中，純實數的符元和純虛數的符元所需之等化器係數為相同的。在決策回授等化器中，純實數符元和純虛數符元所需之前饋濾波器的係數是相同的；但是在回授濾波器的部分，這兩類符元所推導出來的係數在奇數階的地方會相差一個負號、而在偶數階的地方係數則是完全相同。由於在計算此兩種等化器係數時，最主要的複雜度來自於反矩陣的運算，因此利用本論文推導出的等化器性質可以只針對其中一類符元計算係數，而另一類符元的係數則以此性質適當改變後直接使用，故可大幅降低運算的複雜度。

Filter bank multicarrier (FBMC) systems based on offset quadrature amplitude modulation (OQAM) suffer from the inter-symbol interference (ISI) and inter-carrier interference (ICI) in multipath channels and call for equalization to mitigate these effects. In the thesis, we focus on the design of the linear equalizer (LE) and decision feedback equalizer (DFE) that are based on the minimum mean square error (MMSE) criterion. Because the real and imaginary parts of the quadrature amplitude modulation (QAM) symbol are staggered in time in the OQAM scheme, the most straightforward way in equalizer design is to compute the equalizers separately – one for the real part and the other for the imaginary part. In the thesis, we prove the following properties of the equalizer coefficients. For the LE, the equalizer coefficients for the real part are identical to those for the imaginary part. For the DFE, the feedforward filters for the real and imaginary parts are identical. As to the feedback filters, the coefficients of the even-indexed taps for the real part are identical to those of the respective taps for the imaginary part, while the coefficients of the odd-indexed taps for the real part negates those of the respective taps for the imaginary part. Since the computation of the equalizer coefficients requires matrix inversion and dominates the equalizer complexity, the properties proved in the thesis can be used to significantly reduce the computation complexity of the equalizer coefficients.

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