This letter provides an effective solution to deal with the radar cross section (RCS) and mutual coupling of the multiple-input–multiple-output (MIMO) antenna simultaneously. A wideband reflective type polarization converter (PC) is designed and its strategic placement in between the antenna elements of the two-element MIMO antenna has been conceived to mitigate these two issues concurrently. The antenna elements of the proposed MIMO antenna are placed at a proximal distance of 0.088 λ from each other. The proposed MIMO architecture ensures a maximum coupling reduction of 46 dB compared to the conventional MIMO across 4.4–8 GHz. The PC surface reduces the reflection of copolarized waves and enhances cross-polarized reflection. A supercell formed by a unit cell of PC and its 90° rotated counterpart causes phase cancellation of cross- polarized reflected waves, which contributes to wideband RCS reduction by a maximum value of 7 dB. The alignment of PC cells in a column between the adjacent antenna elements causes a reduction in the mutual coupling due to introduction of an extra coupling path and cross-polarization conversion. A good agreement between the simulated and measured results validates this concept of the proposed MIMO design with low RCS and mutual coupling.

中文翻译：

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偏振转换器表面集成 MIMO 天线，可同时减少 RCS 和互耦


该信提供了同时处理雷达散射截面（RCS）和多输入多输出（MIMO）天线互耦合的有效解决方案。设计了宽带反射型偏振转换器 (PC)，并将其战略性地放置在两元件 MIMO 天线的天线元件之间，以同时缓解这两个问题。所提出的 MIMO 天线的天线元件放置在彼此最接近的距离 0.088 λ 处。与传统 MIMO 相比，所提出的 MIMO 架构可确保在 4.4-8 GHz 范围内最大耦合降低 46 dB。 PC表面减少了共极化波的反射，增强了交叉极化反射。由 PC 单元及其 90° 旋转对应物形成的超级单元会导致交叉偏振反射波的相位抵消，这有助于宽带 RCS 降低最大值 7 dB。由于引入了额外的耦合路径和交叉极化转换，相邻天线元件之间的列中的 PC 单元的排列导致互耦合的减少。仿真和测量结果之间的良好一致性验证了所提出的具有低 RCS 和互耦的 MIMO 设计概念。