在先進的MIMO-OFDM系統中，速度需求巨幅攀升，以往tone-by-tone的QR分解處理方式，在QR分解部分耗費相當多的計算，此高運算複雜度特性造成了實作上的瓶頸。為了解決上述傳統作法之高運算量問題，內插式QR分解演算法(interpolation-based QR decomposition, IQRD)已證實能改良傳統作法，降低大量複雜度。因此，此篇論文主要研究內插式QR分解演算法並提出修正的方法已改良運算的複雜度。在利用Q和R矩陣進行解碼的演算法中，由於矩陣R是一上三角矩陣，矩陣解碼順序為由下而上，而第一個進行解碼的信號(symbol)會迭代回方程式中進行後面的信號解碼，因此越早進行解碼的信號，其準確性影響錯誤延遲的情形，對解碼正確率的影響亦越大。在提出的修正方法中，利用上述特性，在進行內插程序時，將相對應於第一個進行解碼信號的最後一列R矩陣之數值使用足夠的pilot數以減少內插錯誤，而其餘的信號則選擇較少的pilot數進行內插以減少運算複雜度且選取的方式為最接近欲內插資料的pilot信號群，透過此種方式可以同時減少運算複雜度和維持解碼準確性。
此外，本篇研究的另一主題是將內插式QR分解應用於結合晶格演算法(LR)的MIMO-OFDM系統。LR已被提出應用於MIMO系統接收端以大幅降低解碼錯誤率，但OFDM系統中的每一個子載波(sub-carrier)皆需要一次LR運算，因此在本論文中提出利用內插式QR分解減少LR在系統中的運算量，並附上模擬的結果、運算量和硬體分析，此外，採用群組(group)架構，在硬體設計上可以根據需求作彈性的調整。從模擬和分析的結果顯示，結合內插式QR分解有效且大幅降低系統複雜度。

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