大規模的多輸入多輸出天線陣列在未來5G通訊中扮演著重要的角色，它能夠在不增加通道頻寬和傳輸能量之下，提升無線系統的資料傳輸率。然而，隨著天線數的增加，多輸入多輸出偵測器的複雜度也相對的提高。因此，在硬體方面，要設計出高效能且低複雜度的多輸入多輸出偵測器成為一項大課題。有許多演算法，例如:內部迭代消去干擾偵測器，能提供高吞吐量且低複雜度，但是效能只能接近最小均方誤差偵測器。基於三角形近似鬆弛偵測器能夠接近最大似然偵測器的效能，但是只支援BPSK和QPSK調變，而且複雜度仍然相當的高。因此，此篇論文提出了晶格簡化預處理之訊號智慧更新內部迭代消去干擾偵測器，能夠支援高QAM調變。雖然效能只能接近最小均方誤差偵測器，但是能夠加快收斂的速度和降低接收端的複雜度。相比於內部迭代消去干擾偵測器，此演算法能夠花費較少的迭代次數，在64-QAM且128×8天線設定下，可以減少95.35%的複雜度。

Massive multiple-input multiple-output (MIMO) was proposed for the higher wireless data transmission rate without increasing channel bandwidth and transmit power. It plays an important role in the prospective fth-generation (5G) wireless communication. Meanwhile, the complexity of the MIMO detector increases signicantly along with the number of antennas. So, the design of high-performance low-complexity MIMO detector is a big challenge in hardware. There are numerous low-complexity MIMO detection algorithms proposed in order to solve this problem. However, many algorithms such as intra-iterative interference cancellation (IIC) detector provide high throughput and lower complexity, but they only approach the performance of the minimum-mean-square-error (MMSE) detector. The triangular approximate relaxation based detector (TASER) can approximate maximum likelihood (ML) detection performance, but is only subject to BPSK and QPSK modulation. However, its complexity still very high. Then, this study proposes a lattice-reduction-aided (LRA) symbol-wise (SW) IIC detector which can support M-QAM modulation. Although being near-MMSE performance, the proposed algorithm has advantages in the higher convergence rate and lower computational complexity in detector parts. The iteration number of the proposed algorithm is less than that of the IIC detector. In 64-QAM 128 x 8 antenna setting MIMO system, the proposed detector reduces about 95:35% computational complexity for IIC detector.

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