In this research work, a 2-port UWB MIMO diversity antenna is designed to operate from 2.7 to 10.5 GHz with −10 dB impedance bandwidth of 118.18%. The proposed design has a total size of 0.57${\lambda }_{2.7}\times 0.28{\lambda }_{2.7}$ (${\lambda }_{2.7}$ is lowest operating wave-length) consists of bi-planar printed fractal radiators whose feeds are contorted in geometry and are diametrically-fed. Characteristics mode analysis (CMA) is introduced to investigate antenna design, feeding technique and modal current distributions. The analysis includes study of modal dynamics, resonance mechanism, bandwidth potentials and modal radiation quality factor. The port-isolation is $⩾$−15 dB when ground plane is truncated by rectangular slots via ellipsoid slot. With an end-connected ground thin neutralization lines, mutual coupling is further reduced by 7.5 dB ($>$−22.5 dB, measured). The diversity performance metrics are evaluated from ECC, CCL, DG, multiplexing efficiency, MEG and TARC. ECC is low $<$0.17 (from far-field magnitudes) and mean effective gain for both ports are $|\mathit{MEG}|$ $<$ 3 dB with $\frac{{\mathit{MEG}}_1}{{\mathit{MEG}}_2}$ $\approxeq$ 1, which is serviceable for UWB multi-standard mobile/wireless/sensor ad-hoc diversity systems. An equivalent circuit model is also designed and the prototype of antenna is fabricated and measured to validate its performance.

在这项研究工作中，设计了2端口UWB MIMO分集天线，以2.7至10.5 GHz的频率工作，-10 dB阻抗带宽为118.18％。拟议的设计总大小为0.57${\lambda }_{2.7}\times 0.28{\lambda }_{2.7}$ （${\lambda }_{2.7}$最小的工作波长）由双平面印刷的分形辐射器组成，它们的进料在几何形状上是扭曲的，并且是按直径进给的。引入特性模式分析（CMA）来研究天线设计，馈电技术和模态电流分布。分析包括模态动力学，共振机理，带宽势和模态辐射品质因数的研究。端口隔离为$⩾$当接地平面通过椭圆形槽被矩形槽截断时，−15 dB。使用末端连接的接地细中和线，相互耦合进一步降低了7.5 dB（$>$-22.5 dB，测量值）。从ECC，CCL，DG，复用效率，MEG和TARC评估分集性能指标。ECC低$<$两个端口的0.17（来自远场幅度）和平均有效增益为 $|\mathit{梅格}|$ $<$ 3 dB $\frac{{\mathit{梅格}}_{\mathrm{1个}}}{{\mathit{梅格}}_2}$ $\approxeq$ 1，可用于UWB多标准移动/无线/传感器自组织分集系统。还设计了等效电路模型，制造并测量了天线原型，以验证其性能。