This paper proposes and analyses a set of novel and optimum multi-streaming techniques for mmWave multi-input multi-output systems. It formulates an optimization problem that enables exploiting available uncorrelated paths between the transmitter (Tx) and the receiver (Rx) to enhance the system throughput. In the proposed approach, antenna arrays at Tx/Rx are modeled as a Bipartite graph. Next, two bi-clustering algorithms are applied to the graph to simultaneously cluster antenna elements at Tx and Rx. In addition, the paper shows how the selection of subchannels and their corresponding subantenna arrays can be reduced to a variant of the graph coloring problem, based on which, two algorithms are proposed to find the optimum subchannels and subantenna arrays. Moreover, the paper defines two new beamforming methods and proves that those methods satisfy constant modulus and total power constraints. The first modified beamforming method uses singular vectors (SVs) of subchannels between Tx/Rx and incorporates the Power Iteration algorithm to decrease singular value decomposition complexity. The second newly proposed beamforming method finds precoders/combiners without using SVs which reduces the computational complexity. Performance evaluations in terms data streaming sum-rate demonstrate that the proposed technique increases the throughput using a low processing complexity.

中文翻译：

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通过双聚类、图形着色和混合波束成形的低成本毫米波 MIMO 多流

本文针对毫米波多输入多输出系统提出并分析了一套新颖且优化的多流技术。它制定了一个优化问题，可以利用发射器 (Tx) 和接收器 (Rx) 之间的可用不相关路径来提高系统吞吐量。在所提出的方法中，Tx/Rx 处的天线阵列被建模为二部图。接下来，将两种双聚类算法应用于图形以同时对 Tx 和 Rx 处的天线单元进行聚类。此外，该论文还展示了如何将子信道及其相应子天线阵列的选择简化为图着色问题的变体，在此基础上，提出了两种算法来寻找最佳子信道和子天线阵列。而且，该论文定义了两种新的波束成形方法，并证明这些方法满足恒模和总功率约束。第一种改进的波束成形方法使用 Tx/Rx 之间子信道的奇异向量 (SV) 并结合功率迭代算法来降低奇异值分解的复杂性。第二种新提出的波束成形方法在不使用 SV 的情况下找到预编码器/组合器，从而降低了计算复杂度。数据流总和方面的性能评估表明，所提出的技术使用低处理复杂性增加了吞吐量。第二种新提出的波束成形方法在不使用 SV 的情况下找到预编码器/组合器，从而降低了计算复杂度。数据流总和方面的性能评估表明，所提出的技术使用低处理复杂性增加了吞吐量。第二种新提出的波束成形方法在不使用 SV 的情况下找到预编码器/组合器，从而降低了计算复杂度。数据流总和方面的性能评估表明，所提出的技术使用低处理复杂性增加了吞吐量。