雙空時區塊碼之軟式輸出球面解碼

Soft-Output Sphere Detection of Double Space-Time Block Codes

黎彥呈(Yan-Cheng Li)

指導教授 ： 白宏達

國立臺北大學/電機資訊學院/通訊工程研究所/碩士(2013年)

摘要

最近在雙空時區塊碼中，提出一個快速最大似然偵測演算法具有低複雜地計算。然而，它僅提供硬式輸出。在這篇論文中，我們把快速最大似然偵測演算法延伸到提供軟式輸出，這樣在雙空時區塊碼獲得接近最佳性能。這個延伸是利用單一樹狀搜索法的技術，它被開發用於多輸入多輸出的通訊系統中。模擬結果顯示提出的軟式輸出演算法優於硬式輸出約3 dB，而其複雜度低於暴力演算法61.15%。

關鍵字

快速最大似然偵測法 ； 雙空時區塊碼 ； 單一樹狀搜索 ； 多重輸入多重輸出 ； 軟式輸出演算法

並列摘要

A fast maximum-likelihood (ML) detection algorithm with low computational complexity was proposed for double space-time block codes (DSTBCs) recently. However, it only provides hard outputs. In this thesis, we extend the fast ML detection algorithm to offer soft outputs such that near-optimum performance of the DSTBC is obtained. This extension is done by using the single-tree search (STS) technique which was developed for spatial multiplexing in multiple-input multiple-output communication systems. Simulation results show that the proposed soft-output algorithm outperforms the hard-output one approximately by 3 dB while its complexity is lower than the brute-force algorithm around 61.15%.

並列關鍵字

double space-time block codes ； single-tree search ； multiple-input multiple-output ； soft-output algorithm

參考文獻

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