A dual-port metasurface (MS) antenna for pattern-diversity applications is proposed. The planar MS, consisting of 4 × 4 square patches, is excited by a driven patch. A pair of differential probe feed is used to drive the patch with broadside mode, while a stepped probe feed is employed in the center of the patch to generate conical mode. The capacitive-loaded stepped probe of the center feed is able to adjust the operating frequency of the conical mode and provide the two different modes with a wide overlapped frequency range. A prototype of the antenna was fabricated and measured for demonstration. The measured overlapped bandwidth (| S 11 | < −10 dB) is 11.2% ranging from 5.11 to 5.72 GHz. Within the band, the measured peak gain is 11.5 dBi for the broadside mode and 6.8 dBi for the conical mode. High isolation of greater than 32 dB between the two ports is achieved over the band. Benefiting from the gain and bandwidth improvement brought by the MS, the proposed pattern diversity antenna is attractive for many wireless communication systems.

中文翻译：

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具有模式分集的超表面天线设计


提出了一种用于模式分集应用的双端口超表面（MS）天线。平面 MS 由 4 × 4 方形贴片组成，由驱动贴片激发。一对差分探头馈电用于以宽边模式驱动贴片，而贴片中心采用阶梯式探头馈电以产生圆锥模式。中心馈电的电容负载阶梯式探头能够调节锥形模式的工作频率，并为两种不同的模式提供较宽的重叠频率范围。制作并测量了天线原型以进行演示。测得的重叠带宽 (| S 11 | < -10 dB) 为 11.2%，范围为 5.11 至 5.72 GHz。在该频段内，测得的宽边模式峰值增益为 11.5 dBi，锥形模式为 6.8 dBi。两个端口之间在整个频带内实现了大于 32 dB 的高隔离度。受益于MS带来的增益和带宽改进，所提出的方向图分集天线对许多无线通信系统具有吸引力。