在先進的MIMO-OFDM系統中速度需求巨幅攀升，以往tone-by-tone 的QR分解構成高運算複雜度，形成了實作上的瓶頸。為了解決此問題，內差式QR分解演算法已證實能降低大量複雜度。本論文提出 one step function 降低內插式QR分解演算法的複雜度，並且加入可規模性讓演算法適用於不同大小的通道矩陣。此外，藉由導入群序(Group order)概念進入內插式QR演算法，群序型內插式QR演算法被提出以提升偵測效能。根據我們所知，提出的內插式QR分解演算法是截至目前為止複雜度最低的QR分解演算法。內插式QR分解的可更改設定之硬體架構被提出，並且選用多候選人制QR-SIC 與之配合。多候選人制QR-SIC擁有可規模化運算複雜度還有彈性效能。內插式QR分解和多候選人制QR-SIC的整合可以實現一套低複雜度且高效能的MIMO detector於各種的MIMO-OFDM系統。因此，多候選人制QR-SIC的迭代式硬體架構被提出，縮短其電路延遲使其運作在更高頻的速度上，並顯示在低維度調變方式時，其有等同於ML的表現。結合上述兩者，提出的QR-based MIMO 架構可支援4x4. 4x2 和2x2通道矩陣，以及QPSK, 16-QAM 和 64-QAM 的調變方式。根據 90nm UMC COMS製程的初步合成結果，提出之內插式QR分解的速度高達31.25 MQRD/s，可以支援3GPP-LTE Rel. 8的硬體規格中下傳鏈路的最高速度。

The throughput requirement of advanced MIMO-OFDM systems increases tremendously recently. The complexity of tone-by-tone QR decomposition becomes the bottleneck of implementation. The interpolation-based QR decomposition(IQRD) algorithm has been proven to reduce the complexity. In the thesis, a one step function is proposed to reduce more complexity of IQRD, and the scalability for different-size channel matrices is attractive to implementation. Moreover, a group-ordering interpolation-based QR decomposition (GO-IQRD) is presented by introducing group-ordering concept into IQRD to increase detection performance. To our best knowledge, the proposed QR decomposition has the lowest complexity among QR decomposition algorithms. A configurable architecture of IQRD without group-order is proposed. Besides, QR-based successive interference cancellation (SIC)
with multiple-candidate selection (MCS-QR-SIC) which has scalable complexity and flexible performance is chosen to cooperate with IQRD. These flexible algorithms are integrated together to be a MIMO detector which could be realized in many MIMO-OFDM systems. The iterative architecture of MCS-QR-SIC is presented. The shorten critical path enables it to work on higher frequency, and it shows the proposed hardware could achieve ML detection performance by controller in low-order modulation. Hence, a QR-based MIMO architecture which supports 4 x 4, 4 x 2, and 2 x 2 channel matrices, with QPSK, 16-QAM, and 64-QAM modulations in the specified bandwidth in the 3GPP-LTE standard is presented. The synthesis result of proposed interpolation-based QR decomposition with UMC 90nm 1P9M CMOS technology shows the corresponding throughput is up to 31.25 MQRD/s, so it could meet the requirement of the highest downlink data rate in hardware categories for 3GPP-LTE Rel. 8.

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