论文名称“K-/Ka-Band planar shared-aperture phased array antenna for

simultaneous transmitting and receiving low earth orbit satellite communication terminal”。针对低轨卫星通信 K/Ka频段相控天线方案在口径集成后通道密度大导致的单元间耦合强、有效带宽窄、波束扫描范围窄、异频通道隔离度差、不易大口径扩展中的若干问题，本文从 1.5 倍频比拓扑优化、多级嵌入式滤波馈电、圆极化分区感应电流抑制出发，综合解决K/Ka频段扫描天线宽角宽带、高隔离度及低剖面问题，与现有同频滤波天线相比剖面降低 60%，整体剖面 3 mm，与同频低剖面天线相比口径隔离度提升约 20 dB，高低频单元带内隔离度优于 38/41 dB，高、低频天线分别具备左旋和右旋圆极化±60°波束扫描能力，实现双毫米波频段扫描天线高效率口径复用。工作主要完成人：张锦帆，程钰间。

论文链接：https://ieeexplore.ieee.org/document/10151799/

Abstract: A planar shared-aperture beam-scanning array antenna for simultaneous transmitting and receiving satellite communication is proposed. The antenna operates in dual working bands with right-handed circular polarization (RHCP) from 17.7 to 21.2 GHz and left-handed circular polarization (LHCP) from 27.5 to 31.0 GHz. For the K-/Ka-band sharedaperture beam-scanning array antenna, the main challenge is to simultaneously achieve a wide beam scanning range, low profile, and high cross-band isolation. Compared to high-profile endfire duplexing or filtering antennas, planar laminated antennas have a stronger coupling between two elements operated at different frequency bands. In this design, two embedded two-stage filters are proposed and integrated into the dual-band feeders. The minimum spacing between the elements is 1/4 wavelength, and both in-band wideband impedance matching and cross-band filtering are performed simultaneously. First, two square lattices with a 45◦ rotation angle between them and a non-stacked topology are employed in the design of uniform arrays for both bands. This design is better suited for this filtering array. Second, to improve CP performance during beam scanning, the Ka-bandinduced current on the K-band radiator should be suppressed. The rotary feed phase and the segmented patch are used to suppress the induced current and produce the reverse induced current in the small and large beam scanning area, respectively. Finally, the equivalent circuits and chain matrices are used to design the filtering feeders. As a result, the dual cross-band isolations increase to 38 and 41 dB. The total profile is less than 3.2 mm, much smaller than the existing K-/Ka-band filtering antenna’s profile of 10 mm, and the proposed design also has a wide operating bandwidth and a large beam scanning range of ±60◦ .

Index Terms— Circular polarization, K-/Ka-band, low earth orbit (LEO) satellite communication, low profile, shared aperture beam-scanning array antenna.