Fakharian Mohammad M, Alibakhshikenari Mohammad, See Chan Hwang, Abd-Alhameed Raed
Faculty of Engineering, University of Garmsar, Garmsar, Iran.
Department of Signal Theory and Communications, Universidad Carlos III de Madrid, 28911, Leganés, Madrid, Spain.
Sci Rep. 2022 Mar 8;12(1):4044. doi: 10.1038/s41598-022-07866-1.
An offset quad-element, two-port, high-gain, and multiband multiple-input multiple-output (MIMO) planar antenna based on a log-periodic dipole array (LPDA) for Ku/K-band wireless communications is proposed, in this paper. A single element antenna has been designed starting from Carrel's theory and then optimized with a 50-Ω microstrip feed-line with two orthogonal branches that results mainly in a broadside radiation pattern and improves diversity parameters. For experimental confirmation, the designed structure is printed on an RT-5880 substrate with a thickness of 1.57 mm. The total substrate dimensions of the MIMO antenna are 55 × 45 mm. According to the measured results, the designed structure is capable of working at 1.3% (12.82-12.98 GHz), 3.1% (13.54-13.96 GHz), 2.3% (14.81-15.15 GHz), 4.5% (17.7-18.52 GHz), and 4.6% (21.1-22.1 GHz) frequency bands. Additionally, the proposed MIMO antenna attains a peak gain of 4.2-10.7 dBi with maximum element isolation of 23.5 dB, without the use of any decoupling structure. Furthermore, the analysis of MIMO performance metrics such as the envelope correlation coefficient (ECC) and mean effective gain (MEG) validates good characteristics, and field correlation performance over the operating band. The proposed design is an appropriate option for multiband MIMO applications for various wireless systems in Ku/K-bands.
本文提出了一种基于对数周期偶极子阵列（LPDA）的偏置四单元、两端口、高增益、多频段多输入多输出（MIMO）平面天线，用于Ku/K频段无线通信。单个单元天线已根据卡雷尔理论设计而成，然后采用具有两个正交分支的50Ω微带馈线进行优化，这主要产生了一个宽边辐射方向图并改善了分集参数。为了进行实验验证，将设计结构印制在厚度为1.57mm的RT-5880基板上。该MIMO天线的基板总尺寸为55×45mm。根据测量结果，设计结构能够在1.3%（12.82 - 12.98GHz）、3.1%（13.54 - 13.96GHz）、2.3%（14.81 - 15.15GHz）、4.5%（17.7 - 18.52GHz）和4.6%（21.1 - 22.1GHz）频段工作。此外，所提出的MIMO天线在不使用任何去耦结构的情况下，实现了4.2 - 10.7dBi的峰值增益以及最大23.5dB的单元间隔离。此外，对诸如包络相关系数（ECC）和平均有效增益（MEG）等MIMO性能指标的分析验证了良好的特性以及在工作频段上的场相关性能。所提出的设计是Ku/K频段各种无线系统多频段MIMO应用的合适选择。
