多輸入多輸出系統之低複雜度偵測器研究

Abstract

在這篇論文我們學習B-Chase檢測器被應用在多輸入多輪出系統和多輸入多輪出正交分頻多工系統。B-Chase檢測演算法是一個廣義技術它能夠提供先前所提過的檢測器當作一個特殊的實例它包含了最大概似檢測器和決策返迴檢測器。這 B-Chase檢測器包含一個列舉檢測器,它能夠被列舉長度l所參數化。介由改變長度,我們能夠處理系統效能和複雜度。 此外, 這 B-Chase檢測器提供兩個選擇演算法它們能夠執行一個工作去決定那一個先進來被檢測。並且列舉長度能夠影響那一個信號被第一個被檢測。這兩個選擇演算法所抉擇的信號根據兩個不同準則所決定。第一個方法是建立在接收信號的雜訊比在那裡,信號被選擇在比較高的優先權如果它有比較高的雜訊比。這個方法使得列舉檢測器的結果能夠更正確,因此下降錯誤傳送的風險。在其它方面,為了下降複雜度的需要當介由第一選擇演算法,在第二個方法執行這個選擇在這個子檢測器,能以效能去交換複雜度。最後,我們應用低複雜度B-Chase檢測演算法到多輸入多輪出正交分頻多工系統。

We study the B-Chase detector applied to the MIMO and MIMO-OFDM systems in this thesis. B-Chase detection algorithm is a general technique that can accommodate previously reported detectors as special cases, including the maximum-likelihood and decision-feedback detectors. The B-Chase detector includes a list detector that is parameterized by the list length l. By changing the list length, we can manage the system performance and complexity. In addition, the B-Chase detector provides two selection algorithms that perform the task to decide which incoming symbol is firstly detected. And the list length can impact which symbol is firstly detected. The choice of two symbol selection algorithms is determined according to two different criteria. The first approach is based on the received SNR in which the symbol is selected in a higher priority if it has a higher SNR. This way the result of the list detector is more likely to be correct, thereby reducing the risk of error propagation. On the other hand, in order to reduce the complexity entailed by the first selection algorithm, the 2nd approach performs the selection in the sub-detectors, with the performance traded to the complexity. Finally, we apply the low-complexity B-Chase algorithm to the MIMO-OFDM systems.