CPW馈电的高隔离度超宽带MIMO槽天线设计

Design of Ultra-Wideband Multi-Input Multi-Output Slot Antenna with High Isolation Fed by Coplane Waveguide

为满足高速率无线通信对超宽带(UWB)传输的要求,该文设计了一种高隔离度超宽带多输入多输出(MIMO)槽天线。天线采用共面波导(CPW)馈电,印制在相对介电常数为4.4的FR4介质基板上。通过对天线地板切角,天线实现了良好的阻抗匹配。实测阻抗带宽为2.88~11.18 GHz,相对带宽达118.1%。为了降低耦合度,两个辐射单元间采用中和线结构,实现了天线的高隔离度。实验表明,在工作频带内,天线的端口隔离度大于20 dB,包络相关系数(ECC)小于0.002,分集增益(DG)大于9.996 dB,分集性能良好,该天线适用于超宽带无线通信系统。

An ultra-wideband(UWB)multi-input multi-output(MIMO)slot antenna with high isolation was designed in this paper in order to meet the requirements of ultra-wideband transmission for high rate wireless communication.It was fed by coplane waveguide(CPW)and printed on FR4 dielectric substrate with a relative permittivity of 4.4.By cutting the corners to the antenna floor,the good impedance matching has been realized.The measured impedance bandwidth of the antenna is from 2.88 GHz to 11.18 GHz,and the fractional bandwidth reaches 118.1%.In order to reduce the coupling degree,the neutralization line structure is used between the two radiating elements of the antenna,which realizes the high isolation of the antenna.The experimental results show that in the working frequency band,the port isolation degree of the antenna is more than 20 dB.The envelope correlation coefficient(ECC)is less than 0.002 and the diversity gain(DG)is greater than 9.996 dB.The antenna has good diversity performance and is suitable for UWB wireless communication systems.