基于平衡馈电的倍频程宽波束紧缩场馈源*

Based on balanced feed octave wide beamwidth compact range feed

摘要:

设计了一种工作在 4GHz~8GHz 的基于平衡馈电的宽波束中心脊喇叭馈源。馈源的中心脊为十字形，位于喇叭中心。四个同轴探针旋转对称分布，外导体连接喇叭壁，内导体与十字形中心脊的四个脊片分别连接，通过向正对的同轴探针馈入等幅反相的差分信号实现平衡馈电，抑制高次模的产生。中心脊波导喇叭截止频率较低的前三个模式分别为 TE₁₁模，TE_21L 模和 TE_21U模式，其中， TE₁₁模是馈源的主模式。针对馈源的模式分布分析馈源具有宽带特性的原因。在喇叭口面位置加载三个优化设计的轴向波纹槽，获得稳定的宽波束辐射方向图。设计的馈源在频带范围内 VSWR<1.9，–3dB 波束宽度>51.5°，E 面和 H 面交叉极化

Abstract:

MicrosoftInternetExplorer402DocumentNotSpecified7.8 磅Normal0 An octave wide beamwidth central quad-ridged horn feed based on balanced feed over 4 GHz~8 GHz is designed in this paper. The central quad-ridge of the feed located at the center of the horn is cross-shaped. The external conductors of the four coaxial probes are connected to the horn wall, and internal conductors insert into central quad-ridge rotating symmetrically. Balanced feeding is achieved by feeding two coaxial probes in opposite directions with differential signals of constant amplitude and inverse-phase, which suppresses the excitation of higher order modes. The three axial corrugated slots are applied at the edge of horn aperture to obtain a stable wide beamwidth radiation pattern. The first three modes with relatively low cut-off frequencies, TE₁₁, TE_21L, TE_21U. TE₁₁is the dominant mode of the feed. Mode analysis explains the reason why the feed has broadband. The designed feed has VSWR <1.9, -3dB beamwidth>51.5° within the frequency band, E plane, and H plane cross polarization <-30dB, and the variation range of the phase center is less than 0.32l (l is the wavelength at 4GHz).