The millimeter-wave channel estimation problem can be solved by estimating the path directions and the path gains. The previous schemes are nearly all based on the uniform linear arrays (ULAs). However, compared with the ULAs, the co-prime array can use fewer array elements to realize larger array aperture, which is beneficial to improve the performance of arrival direction estimation contributing to the estimation performance of angle of arrival (AOA) and angle of departures (AOD). Encouraged by the property of co-prime arrays, a novel channel estimation scheme is proposed for two-dimensional (2-d) co-prime arrays. For each path direction, multiple peaks are generated in the spatial spectrum of each subarray and by selecting over any limited sector to search for an arbitrary peak, which can recover the rest peaks. Then by comparing the peaks of the two subarrays, the common peaks are the correct path direction. Compared with the total-spectrum search (TSS) method, this method effectively reduces the complexity. Simulation results show that the proposed algorithm can reduce the computational complexity and maintain accurate channel estimation.

中文翻译：

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基于PSS-MUSIC的配备共基元阵列的毫米波MIMO系统的信道估计

毫米波信道估计问题可以通过估计路径方向和路径增益来解决。先前的方案几乎全部基于统一线性阵列（ULA）。但是，与ULA相比，共质数阵列可以使用较少的阵列元素来实现更大的阵列孔径，这有利于改善到达方向估计的性能，从而有助于到达角（AOA）和偏离角的估计性能（AOD）。受互质阵列的特性的鼓励，提出了一种针对二维（2-d）互质阵列的新型信道估计方案。对于每个路径方向，在每个子阵列的空间谱中并通过选择任何有限的扇区以搜索任意峰（可以恢复其余峰）来生成多个峰。然后，通过比较两个子阵列的峰，共同的峰是正确的路径方向。与全谱搜索（TSS）方法相比，该方法有效地降低了复杂度。仿真结果表明，该算法可以降低计算复杂度，并保持准确的信道估计。