X 波段加膜片式单脊波导裂缝天线的研究

等效导纳值是波导宽边纵缝天线的关键设计参数。为克服传统波导裂缝天线副瓣偏高、设计效率低下等问题,本文提出了一种单脊波导裂缝天线的改进设计方法,在传统波导裂缝阵列天线设计的基础上,利用等效导纳值对天线等效电路的影响,在裂缝单元下增加金属膜片,通过改变金属膜片的高度,优化裂缝等效导纳值,使得每个裂缝口径场分布更加接近于理论设计值,并在设计过程中使用牛顿迭代法提取导纳进一步缩短设计时间。通过设计实例表明:应用此方法设计单脊波导裂缝天线能够有效抑制副瓣电平,天线方位面副瓣电平可达到-30 dB 以下;在满足主要指标要求的前提下,设计效率显著提升。

Research on an X Band Single Ridge Waveguide Slot Antenna with the Metal Diaphragm Slit Technology

The equivalent admittance is a key design parameter of the waveguide slot antenna. The traditional waveguide slot array antennas have higher side lobe and longer design time. An improved design of single ridge waveguide slot arrays is proposed in this paper on the basis of the traditional waveguide slot antenna design. The technique by adding metal diaphragms under slot units is presented to fit the influence of the equivalent admittance on the equivalent circuit of antenna. We can change the height of the metal diaphragm to optimize the admittance of each slot, so that the aperture field distribution of this novel design is closer to the theoretical design value. The admittance is extracted by using Newton iterative method to shorten design time. Simulated results show that the side lobe level of the antenna can be suppressed effectively with this method, the side lobe level can be below -30 dB, and a waveguide slot antenna array can be designed easily and economically in order to meet the requirements of the main indicators.