This two‐part article presents a review of different techniques of mutual coupling (MC) reduction. MC is a major issue when an array of antennas is densely packed. When the separation between the antennas is <λ₀/2, i.e., half of the free‐space wavelength, the antenna parameters suffer from the surface wave, and the space wave coupling effect between the antenna elements. To reduce the MC influence, several techniques have been discussed in the scientific literature. This part of the review paper will discuss strategies: antenna placement and orientation approach, Defected Ground Structures (DGSs), slots/slits‐etching approach, protruding ground stub structures, and parasitic elements/structures. This article concludes with feasibility, applications, and comparison of the techniques mentioned above. Simultaneously, the applications and possibilities of the remaining methods are discussed in part two of the article.

中文翻译：

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任意MIMO天线单元之间互耦减小的不同技术综述。第1部分：DGS和寄生结构

这篇分为两部分的文章介绍了互耦（MC）降低的不同技术。当密集排列天线阵列时，MC是一个主要问题。当天线之间的分离是< λ ₀/ 2，即自由空间波长的一半，天线参数受到表面波的影响，并且受到天线元件之间的空间波耦合效应的影响。为了减少MC的影响，在科学文献中已经讨论了几种技术。这篇综述文章的这一部分将讨论策略：天线放置和定向方法，变形接地结构（DGS），缝隙/狭缝蚀刻方法，突出的接地桩结构以及寄生元件/结构。本文以上述技术的可行性，应用和比较作为结束。同时，本文第二部分讨论了其余方法的应用和可能性。