本論文討論之偏移正交振幅調變濾波器組多載波空間多工(spatial multiplexing filter bank multicarrier with offset quadrature amplitude modulation, SM-FBMC)系統是未來世代行動通訊系統考慮之傳輸技術之一。相較於現行系統之正交分頻多工(orthogonal frequency division multiplexing, OFDM)技術，其頻譜具有較低之旁波瓣，對鄰近頻帶之使用者影響較小，可減少保護頻帶(guard band)，也不須使用循環字首(cyclic prefix, CP)，故具有較高之頻譜效率，且對頻率偏移的容忍度亦較高。然而，在頻率選擇性通道中，SM-FBMC系統之接收端必須有效地克服符元間、天線間、與子通道間干擾，方能提高偵測效能。目前文獻中針對SM-FBMC系統提出之偵測技術多屬奠基於線性等化器之偵測器。在頻率選擇性較嚴重之通道中，其偵測效能不彰(並導致錯誤率平層(error-rate floor))，且偵測延遲與運算複雜度極高。本論文貢獻有二：首先，我們提出兩種新型之偵測器架構，以決策回授等化器(decision feedback equalizer, DFE)為基礎，在不增加偵測延遲之前提下，使用多個回授濾波器(feedback filter, FBF)消除符元間、天線間、與子通道間干擾，使之提高偵測效能，消除錯誤率平層。再者，我們利用SM-FBMC的特殊訊號結構，提出更有效率但在數學上維持等價之等化器係數計算方式，使其計算等化器係數所需之運算複雜度較線性等化器更低。

This thesis focuses on the spatial multiplexing filter bank multicarrier with offset quadrature amplitude modulation (SM-FBMC) system, which is one of the candidates for the future generation of mobile communication systems. SM-FBMC employs the prototype filter that has very small spectral side lobes, which gives the following advantages over orthogonal frequency division multiplexing (OFDM): (1) The spectral guard bands can be reduced, and the cyclic prefix (CP) is not required. (2) It is less sensitive to the frequency offset. In frequency-selective channels, however, inter-symbol interference (ISI), inter-antenna interference (IAI), and inter-subchannel interference (ICI) arise as major sources of performance impairments in SM-FBMC systems, which calls for advanced detectors to attain a satisfactory performance. In the literature, the linear equalizer (LE) based detectors were proposed for SM-FBMC systems. The performances of them are usually limited by error-rate floors in highly frequency-selective channels, and they suffer from a high computational complexity and a considerable increase in detection latency. The contributions of the thesis include the following. First, we propose new decision feedback equalizer (DFE) based detectors that use multiple feedback filters to cancel ISI, IAI, and/or ICI. These detectors achieve a significant performance gain over the conventional DFE and remove the error-rate floor, but without increasing the detection latency. Second, by exploiting the special structures of SM-FBMC signals, we obtain a more efficient, and yet mathematically equivalent, method of computing the DFE coefficients that even requires a smaller complexity (in calculating the equalizer coefficients) than LE.

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