A codesigned hepta-band antenna with a large frequency ratio is presented by using a mode-composite method. The method is based on an idea that apart from a quasi-TE10 mode transmitting in a substrate integrated waveguide (SIW) structure at millimeter-wave frequencies, additional radiation modes of the wire antennas can be excited simultaneously on the outer surface of a well-designed SIW structure at the microwave frequencies much lower than its cut-off frequency. In this design, a combination of a meander SIW section and an L-shaped SIW section that are connected with a metallic ground plane constructs the mode-composite structure. Two slot antenna arrays with a size of $2\times4$ are implemented in the SIW sections for the radiation in the 28 GHz and 38 GHz bands. Unidirectional features with low backward radiation can be achieved with the aid of parasitic dipole elements close to the slots. A T-shaped probe operating as a coupled feed is applied to excite five radiation modes existing on the outer surface of the mode-composite structure, which can cover five sub-6 GHz bands for the LTE and 5G mobile communications and the WLAN applications. Stable radiation characteristics are maintained at the microwave frequencies. The work paves a new means to design the compact multiband antenna with a large frequency ratio, which would be attractive for future portable devices operating in both microwave and millimeter-wave bands.

中文翻译：

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适用于 6 GHz 以下、28 GHz 和 38 GHz 应用的紧凑型七波段模式复合天线

采用模态复合方法提出了一种大频率比的协同设计的七波段天线。该方法基于这样一种想法，即除了在毫米波频率下在衬底集成波导 (SIW) 结构中传输准 TE10 模式之外，还可以在井的外表面上同时激发线天线的其他辐射模式。设计的 SIW 结构的微波频率远低于其截止频率。在该设计中，与金属接地平面连接的曲折 SIW 部分和 L 形 SIW 部分的组合构成了模式复合结构。在 SIW 部分实施了两个尺寸为 $2\times4$ 的缝隙天线阵列，用于 28 GHz 和 38 GHz 频段的辐射。借助靠近缝隙的寄生偶极子元件，可以实现具有低反向辐射的单向特征。作为耦合馈源的T形探头用于激发存在于模式复合结构外表面上的五种辐射模式，可覆盖LTE和5G移动通信以及WLAN应用的5个sub-6 GHz频段。在微波频率下保持稳定的辐射特性。这项工作为设计具有大频率比的紧凑型多频段天线铺平了道路，这对未来在微波和毫米波频段工作的便携式设备都具有吸引力。作为耦合馈源的T形探头用于激发存在于模式复合结构外表面上的五种辐射模式，可覆盖LTE和5G移动通信以及WLAN应用的5个sub-6 GHz频段。在微波频率下保持稳定的辐射特性。这项工作为设计具有大频率比的紧凑型多频段天线铺平了道路，这对未来在微波和毫米波频段工作的便携式设备都具有吸引力。作为耦合馈源的T形探头用于激发存在于模式复合结构外表面上的五种辐射模式，可覆盖LTE和5G移动通信以及WLAN应用的5个sub-6 GHz频段。在微波频率下保持稳定的辐射特性。这项工作为设计具有大频率比的紧凑型多频段天线铺平了道路，这对未来在微波和毫米波频段工作的便携式设备都具有吸引力。