论文标题
截短的光束清除杂交大型MIMO中的空间协方差矩阵重建
Truncated Beam Sweeping for Spatial Covariance Matrix Reconstruction in Hybrid Massive MIMO
论文作者
论文摘要
空间协方差矩阵（SCM）在多种端纳系统的许多应用中至关重要，例如大量多输入多输出（MIMO）。对于在毫米波带上运行的大型MIMO，已经采用了混合模拟数字结构来降低射频（RF）链的成本。在这种情况下，数字接收器无法使用在天线中收到的信号，因此，在混合大型MIMO中，传统的样本平均方法不能用于SCM重建。为了解决这个问题，在我们以前的工作中提出了可以有效地在杂化大型MIMO中重建SCM的光束扫描算法（BSA）。在本文中，通过考虑阵列中天线元件的模式，进一步提出了SCM重建的截短BSA。由于指令天线模式，远离正常方向的预先确定的角度方向（DOA）对应的扫描结果很小，因此可以被预定的常数取代。以降低性能的成本为代价，可以通过仅扫描接近正常方向的预定的DOA来有效地重建SCM。这样，BSA的进行比传统的速度快得多。还将包括有见地的分析，以显示截断对性能的影响。
Spatial covariance matrix (SCM) is essential in many applications of multi-antenna systems such as massive multiple-input multiple-output (MIMO). For massive MIMO operating at millimeter-wave bands, hybrid analog-digital structure has been adopted to reduce the cost of radio frequency (RF) chains. In this situation, signals received at the antennas are unavailable to the digital receiver, and as a consequence, traditional sample average approach cannot be used for SCM reconstruction in hybrid massive MIMO. To address this issue, beam sweeping algorithm (BSA), which can reconstruct SCM effectively in hybrid massive MIMO, has been proposed in our previous work. In this paper, a truncated BSA is further proposed for SCM reconstruction by taking into account the patterns of antenna elements in the array. Due to the directive antenna pattern, sweeping results corresponding to predetermined direction-of-angles (DOA) far from the normal direction are small and thus can be replaced by predetermined constants. At the cost of negligible performance reduction, SCM can be reconstructed efficiently by sweeping only the predetermined DOAs that are close to the normal direction. In this way, BSA can be conducted much faster than its traditional counterpart. Insightful analysis will be also included to show the impact of truncation on the performance.
