Islam Hashinur, Das Saumya, Ali Tanweer, Kumar Pradeep, Dhar Sourav, Bose Tanushree
Department of Electronics and Communication Engineering, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India.
Department of Information Technology, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India.
Sensors (Basel). 2021 Mar 24;21(7):2256. doi: 10.3390/s21072256.
The ever-growing expectation for high data rates has led to the introduction of multiple-input multiple-output (MIMO) technologies to wireless connectivity. Such a system requires an MIMO antenna with high isolation. At the same time, the MIMO dimension should not be compromised for achieving high isolation. Thus, isolation techniques that do not allow an increase in dimension need to be fostered for MIMO antenna design. In this paper, a novel low-profile, miniaturized MIMO antenna with high isolation was developed considering a split ring resonator (SRR)-based bandstop filter as a decoupling network. The bandstop filter was designed with a unit cell split ring resonator structure and was deployed between two closely spaced monopole MIMO antenna elements to obtain isolation as high as 39.25 dB at 2.61 GHz. Two open-circuit stub lines were attached with the MIMO feeding network to achieve good impedance matching at resonance frequency. The proposed antenna exhibited a peak gain of 3.8 dBi and radiation efficiency of 84%. It had a low envelop correlation coefficient (ECC < 0.12), high diversity gain (DG > 9.95 dB), low mean effective gain ratio (MEG 1/MEG 2 < 0.05 dB), and low channel capacity loss (CCL < 0.042 bits/s/Hz) at resonance frequency. The overall antenna dimension was restricted to 44 mm ×22 mm (0.38 λ0×0.19 λ0) for its easy integration in compact wireless devices.
对高数据速率不断增长的期望促使在无线连接中引入了多输入多输出（MIMO）技术。这样的系统需要具有高隔离度的MIMO天线。同时，为了实现高隔离度，MIMO尺寸不应受到影响。因此，在MIMO天线设计中需要采用不增加尺寸的隔离技术。本文提出了一种新型的低剖面、小型化且具有高隔离度的MIMO天线，该天线将基于裂环谐振器（SRR）的带阻滤波器作为去耦网络。带阻滤波器采用单元裂环谐振器结构设计，并部署在两个紧密间隔的单极MIMO天线单元之间，在2.61 GHz频率下可获得高达39.25 dB的隔离度。两条开路短截线与MIMO馈电网络相连，以在谐振频率处实现良好的阻抗匹配。所提出的天线峰值增益为3.8 dBi，辐射效率为84%。在谐振频率下，它具有低包络相关系数（ECC < 0.12）、高分集增益（DG > 9.95 dB）、低平均有效增益比（MEG 1/MEG 2 < 0.05 dB）和低信道容量损失（CCL < 0.042 bits/s/Hz）。天线的整体尺寸限制为44 mm×22 mm（0.38λ0×0.19λ0），便于集成到紧凑型无线设备中。
