小型化超宽带H面脊喇叭端射天线

Miniaturized Ultra-wideband H-plane Ridged Horn Antenna with End-fire Radiation Pattern

摘要:

超宽带天线技术是实现射频孔径综合的关键技术之一，适用于解决大型电子信息系统中采用多个天线带来的布局困难、互相干扰等问题。本文设计了一款具有端射特性的小型化超宽带H面脊喇叭天线。天线通过加载指数型脊结构，降低了矩形波导的截止频率，从而大幅展宽了天线工作带宽。同时，通过在喇叭口加载单曲面形介质透镜，改善了辐射口面上相位不均匀的问题，进而显著提高了天线的端射增益。该天线结构紧凑，其尺寸仅为0.57 λ_L×0.45 λ_L×0.11 λ_L，可覆盖0.8 GHz~18 GHz的超宽频带，且交叉极化优于30 dB。该天线剖面低、结构稳定、易于加工，可直接安装于金属结构上，易于与载体集成。通过与同类型端射天线相比可知，该天线在小型化和电性能两方面都具有优越性。

Abstract:

With the increasing demand for multi-function and multi-band operation, more antennas have been employed in different electronic systems, which inevitably results in difficulties in antenna arrangement and severe interference. As a key technique of radio-frequency aperture integration, ultra-wideband (UWB) antennas provide an effective solution to this problem. A novel miniaturized UWB H-plane ridged horn antenna with end-fire radiation property is proposed in this paper. In order to broaden the operating bandwidth, an exponential ridge is employed and the cutting-off frequency of the rectangle waveguide is significantly reduced. By extending a hyperbola-shaped dielectric lens from the horn aperture, nearly uniform aperture phase distribution is achieved along the H-plane, which leads to a significant enhancement of the end-fire gain. This antenna has a compact form factor of only 0.57 λ_L×0.45 λ_L×0.11 λ_L and it maintains a wide operating bandwidth ranging from 0.8 GHz to 18 GHz. Moreover, the simulated cross polarization discrimination across the operating bandwidth is better than 30 dB. The antenna structure features a low profile, good stability, and easy fabrication, which can greatly facilitate its integration with metallic structures and missiles. Compared with other reported end-fire antennas, the proposed design shows remarkable superiority in terms of its electrical size and performance.