For square kilometer array (SKA) mid-frequency aperture arrays, dense connected aperture arrays such as Vivaldi antenna arrays are being considered, but to achieve the required system sensitivity for radio astronomical observations, this would mean a large number of antenna elements particularly in the order of millions. Two concepts of regular-on-grid and irregular-on-grid sparse array configuration are introduced for these connected arrays to reduce the number of antenna elements and the sensitivity performance of the two concept arrays is compared. Comparing the effective area of these two configurations, it is shown that a regular-on-grid sparse configuration achieves slightly larger effective area than an equivalent irregular-on-grid sparse configuration. Using the regular-on-grid sparse configuration as a case study, the effect that terminating impedance of the inactive antennas has on the receiver noise temperature of a connected array of Vivaldi antennas is investigated.

中文翻译：

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连通孔径阵列的规则和不规则网格稀疏阵列比较

对于平方公里阵列 (SKA) 中频孔径阵列，正在考虑使用密集连接的孔径阵列，例如 Vivaldi 天线阵列，但要实现射电天文观测所需的系统灵敏度，这将意味着需要大量天线单元，尤其是在数百万的订单。针对这些连接阵列引入了规则网格和不规则网格稀疏阵列配置两个概念，以减少天线元件的数量，并比较两种概念阵列的灵敏度性能。比较这两种配置的有效面积，表明规则网格稀疏配置比等效的不规则网格稀疏配置实现略大的有效面积。使用常规网格稀疏配置作为案例研究，