【摘要】 本文提出一种新颖的正交圆极化双频高效率圆锥喇叭。其原理是在光壁喇叭中放置两个相距一定间隔的介质带。在低频区工作时,基本上只有靠近喇叭口径的介质带对辐射图的等化作出贡献;而在高频区,两个介质带共同对辐射图的等化作出贡献。适当选择这两个介质带的尺寸,即可在高、低频区都获得波瓣等化、旁瓣电平低的喇叭方向图。从而,把“介质加载”技术推广到双频圆极化的应用。 文中介绍了一个设计实例。该喇叭工作于频率比为1:1.40的两个频区中。在每个频区中,方向图的等化带宽约为10％。输入电压驻波比在高、低频区的使用频段中分别小于1.05和1.12。更多还原

【Abstract】 This paper puts forward a new highly efficient conical feed horn which operates with orthogonal circular polarization at two bands. The method is to place two dielectric tapes which are set apart at a certain distance in the smooth wall horn. In low band, only the tape near the aperture contributes mainly to the pattern equalization, while in high band, both tapes contribute to pattern equalization. A rotationary symmetric pattern with low level sidelobe can be obtained by choosing the right size of the two dielectric tapes at two bands. Thus the ’dielectric loaded’ technique is extended to the design of dual frequency circular polarization horn.An example of the design is presented. The horn operates at two bands with frequency ratio of 1:1.40. In each band, the bandwidth of the pattern equalization is approximately 10%. The input VSWR is below 1.05 and 1.12 at high and low operating frequency bands respectively.更多还原