廣義空間調變在單一時間內有多根天線發送訊號，相較傳統空間調變可以有效地提高資料傳輸率，然而隨著發送訊號天線數的增加其天線間干擾更為嚴重，在單載波傳輸廣義空間調變系統中，最大概似偵測器使用窮舉法，故擁有最佳之偵測效能，然而其複雜度也隨著星座點數與有效傳送天線組合數增加呈指數上升。相較於最大概似偵測器，OB-MMSE偵測器重新排列天線組合的偵測順序，盡可能地將正確的天線組合擺在前面，使提早終止的機率增加進而使整體複雜度降低許多。然而文獻中之OB-MMSE偵測器乃是基於頻率平坦衰減通道之假設發展，無法直接使用在常見之頻率選擇性衰減通道。為了解決此問題，本篇論文利用單載波區塊傳輸系統之訊號特性並結合決策回饋與OB-MMSE演算法，設計出能在多重路徑衰減通道中應用之偵測演算法。然而偵測器效能受限於通道衰減導致之錯誤率蔓延，為了改善此問題，我們進一步提出改良機制，當偵測器判斷發生嚴重的錯誤率蔓延時，啟動樹狀搜尋偵測演算法修正部分已決策訊號。根據模擬結果顯示，本論文所提出之偵測演算法其錯誤率改善效果顯著。

Compared with spatial modulation, generalized spatial modulation (GSM) can effectively increase the data transmission rate by simultaneously activating more than one transmit antenna in each channel use. However, as the number of active transmit antennas increases, the interference between antennas becomes more severe. In single-carrier GSM systems, the maximum likelihood (ML) detector achieves the best detection performance since the exhaustive search is applied. Nonetheless, the complexity increases exponentially with the number of constellation points and valid transmit antenna combinations (TACs). Compared with the ML detector, ordered-block minimum-mean-squared-error (OB-MMSE) detector is a low-complexity detector that performs minimum-mean-squared-error (MMSE) detection sequentially for valid TACs. The detection order is devised by attempting to put the correct TAC in front as much as possible. This leads to a high probability of early termination of the sequential test, which results in a significant complexity saving. However, the OB-MMSE detector in the literature is developed for the flat fading channels and can not be directly used in the frequency selective fading channels commonly encountered in wireless communications. In order to overcome this problem, we propose in the thesis a detector that exploits the characteristics of the single-carrier block transmission signals and combines the ideas of decision feedback and the OB-MMSE algorithm. However, the detection performance is limited due to error propagation that results from channel fading. An enhanced mechanism is further proposed to overcome this problem. When the detector determines that severe error propagation has occurred, the tree search detection stage that attempts to correct some of the decision errors is activated. The simulation results show that, although the improved mechanism costs additional complexity, the improvement in the error-rate performance is significant.

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