利用贴片天线的奇偶模实现宽频带辐射零点扫描

设计了一款方向图分集的宽频带贴片天线。该天线由矩形贴片与共面波导馈电结构组成。贴片工 作在偶模或奇模状态,分别对应边射和水平全向辐射方向图。两个辐射模式由一个尺寸为35 mm×14. 5 mm 的馈电 网络激励。馈电网络中的微带线-槽结构和共面波导(CPW)结构分别产生同向和反向电场,从而分别激励贴片的奇 模和偶模,实现宽频带和高隔离。测试结果显示,天线的工作频段为2. 17~2. 95 GHz,工作带宽为780 MHz(31%)。 基于这两个辐射模式,天线可在特定角度产生辐射零点以对抗恶意干扰,且零点的角度随工作频率的变化呈线性变 化规律。该天线可用于MIMO 等智能通信系统。

Wideband Radiation Null Steering Using the Odd / Even Modes of Microstrip Patch Antenna

A broadband patch antenna with two radiation modes is designed. The antenna consists of a rectangular patch and a CPW feeding structure, which can work in the even mode or odd mode, and the corresponding radiation pattern is broadside or horizontal omnidirectional. The two radiation modes can be excited by a single feed network with a size of only 35 mm×14. 5 mm. The microstrip-line-slot structure and CPW structure in the feed network can generate in-phase and out-ofphase electric field respectively, which can separately excite the even and odd modes of the patch to achieve wide bandwidth and high isolation. The test results show that the operating frequency band of the antenna is 2. 17-2. 95 GHz and the working bandwidth is 780 MHz (31%). Based on the two radiation modes, the antenna can generate signal null at a specific angle to reject malicious interference, and the null angle changes linearly with operating frequency. The antenna can be used for intelligent communication systems such as MIMO communication.