本論文針對具空時區塊編碼之相差空間調變系統進行低複雜度解碼器設計與效能分析。首先，針對具空時排列的空時區塊編碼之相差空間調變架構中因排列組合導致之計量運算爆炸問題，提出一種以子計量預先計算與查表重構為基礎之低複雜度最大可能性偵測法。該方法可重複利用相同子矩陣之距離資訊，顯著降低實數乘法次數，並保有與原始偵測器相近之錯誤率表現。
接著，針對進一步提高解碼靈活性與降低記憶體需求，本論文設計一套應用
Fano演算法之序列解碼架構，結合動態門檻控制與節點資訊遞傳機制，能有效進行路徑搜尋與回溯，避免完整遍歷整張籬柵圖。模擬結果驗證，所提解碼器可在中高訊雜比下維持穩定效能，並大幅減少複雜度與資源使用，展現其於高天線數與受限裝置中之實作潛力。

This thesis investigates low-complexity decoder designs for space-time block coded differential spatial modulation (STBC-DSM) systems. A submetric-based maximum-likelihood detection method is proposed to reduce the high computational complexity caused by spatial-temporal permutation, achieving significant complexity reduction while maintaining near-optimal error performance.
To further reduce memory usage and improve decoding flexibility, a Fano algorithm-based sequential decoder is developed. By employing dynamic threshold control and recursive state tracking, the decoder avoids full trellis traversal and adapts to channel conditions.

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