高增益低旁瓣宽扇形波束脊形波导缝隙天线阵列设计

Design of high-gain low-sidelobe wide-sector beam slotted ridge waveguide antenna array

提出了一种具有高增益低副瓣的脊形波导缝隙阵列天线,中心工作频率为24.125 GHz,其包括一个八路馈电网络和一个尺寸为400 mm×65 mm的8×40辐射缝隙。通过波束合成方法提取天线阵列的期望激励分布,采用截止模式功率分配器灵活控制功率比。使用三维电磁仿真软件HFSS综合仿真计算,在中心频率处,获得仰角平面上的旁瓣电平(sidelobe level,SLL)和半功率波束宽度(half power beam width,HPBW)分别为-20.9 dB和54.5°、方位角平面上的SLL和HPBW分别为-27.8 dB和2.5°、峰值增益为23.2 dBi,仿真结果与理论分析一致。此天线可以同时实现低旁瓣的宽扇形波束,覆盖较宽的检测范围,并减轻来自其他方向的干扰,具有应用于空中探测、反无人机、气象雷达和成像雷达的潜力。

In this paper,a slotted ridge waveguide antenna array(SRWAA)with high-gain and low-sidelobe and a center frequency of 24.125 GHz is proposed,consisting of an eight-way feeding network and an 8×40 radiating slot with a dimension of 400 mm×65 mm.The expected excitation distribution for the antenna array is extracted by beam synthesis method.By using a cut-off-mode power divider,the power ratio can be flexibly controlled.The sidelobe level(SLL)and half-power beam width(HPBW)in elevation plane are−20.9 dB and 54.5°,and the SLL and HPBW in azimuth plane are−27.8 dB and 2.5°respectively,and the peak gain is 23.2 dBi by using 3D electromagnetic simulation software HFSS.The simulation results are in good agreement with the theoretical analysis.The SRWAA can realize wide-sector beams with low-sidelobe at the same time,which covers a wide detection range and mitigate the interference from other directions.This work has the potential to be applied to air detection,antidrone,meteorological radar,and imaging radar.