A novel sparse array (SA) structure is proposed based on the maximum inter-element spacing (IES) constraint (MISC) criterion. Compared with the traditional MISC array, the proposed SA configurations, termed as improved MISC (IMISC) has significantly increased uniform degrees of freedom (uDOF) and reduced mutual coupling. In particular, the IMISC arrays are composed of six uniform linear arrays (ULAs), which can be determined by an IES set. The IES set is constrained by two parameters, namely the maximum IES and the number of sensors. The uDOF of the IMISC arrays is derived and the weight function of the IMISC arrays is analyzed as well. The proposed IMISC arrays have a great advantage in terms of uDOF against the existing SAs, while their mutual coupling remains at a low level. Simulations are carried out to demonstrate the advantages of the IMISC arrays.

中文翻译：

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基于最大元素间距准则的新型稀疏阵列设计

基于最大元素间距（IES）约束（MISC）准则，提出了一种新颖的稀疏阵列（SA）结构。与传统的 MISC 阵列相比，被称为改进 MISC (IMISC) 的 SA 配置显着增加了均匀自由度 (uDOF) 并减少了相互耦合。特别是，IMISC 阵列由六个均匀线性阵列 (ULA) 组成，它们可以由一个 IES 集确定。IES 集受两个参数约束，即最大 IES 和传感器数量。推导了IMISC阵列的uDOF，并分析了IMISC阵列的权重函数。所提出的 IMISC 阵列在 uDOF 方面相对于现有 SA 具有很大优势，而它们的相互耦合仍然处于较低水平。