The improved dual-layer mushroom (IDLM) and back-to-back E-shaped stubs for mutual coupling reduction between microstrip patch antennas are presented in this paper. The IDLM unit consists of one upper layer complementary split-ring resonator lattice and four lower layer lattices, whose centers are connected to the ground by a pin. The decoupling structure can prevent the surface current from one antenna port to another, so as to improve the isolation between the antennas. The proposed antenna works in the open wireless communication band of 2.45 GHz. Using the proposed decoupling structure, a low mutual coupling level ranging from −27 to −40 dB is obtained when the center distance of the adjacent patches is 0.5λ₀. The total size of the decoupling antenna is 99 × 41 × 2.4 mm³ with a frequency range of 2.42–2.48 GHz for S₁₁ < −10 dB. The proposed decoupling structure can also improve the average gain and efficiency of the antenna by 0.1 dB and 5%, respectively. The antenna is studied from the aspects of isolation, return loss, current and electric field distribution, radiation pattern, and diversity performance. The designed decoupling antenna is fabricated and measured. The pattern, isolation, and return loss of the tested results show good consistence with the simulation results. The diversity gain and envelop correlation coefficient of the diversity performance show that the designed antenna can be used in MIMO or Rx/Tx systems.

中文翻译：

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使用改进的双层蘑菇和电子形状的短截线减少相互耦合

本文提出了改进的双层蘑菇（IDLM）和背对背的E形短截线，用于减少微带贴片天线之间的相互耦合。IDLM单元由一个上层互补开口环谐振器晶格和四个下层晶格组成，它们的中心通过引脚连接到地面。该去耦结构可以防止表面电流从一个天线端口流向另一个天线端口，从而提高了天线之间的隔离度。拟议的天线在2.45 GHz的开放无线通信频段中工作。使用所提出的去耦结构中，当相邻的贴片的中心间距离为0.5，获得低的相互耦合电平范围从-27到-40分贝λ ₀。去耦天线的总尺寸为99×41×2.4 mm ³对于S ₁₁  <-10 dB，频率范围为2.42-2.48 GHz 。所提出的去耦结构还可以分别将天线的平均增益和效率提高0.1 dB和5％。从隔离度，回波损耗，电流和电场分布，辐射方向图和分集性能等方面对天线进行了研究。设计并制造了去耦天线。测试结果的模式，隔离度和回波损耗与仿真结果显示出良好的一致性。分集性能的分集增益和包络相关系数表明，所设计的天线可用于MIMO或Rx / Tx系统。