基于平面环状缝隙结构的宽带高增益频率扫描阵列天线

Compact Broadband High Gain Frequency Scanning Array Antenna based on Planar Annular Slot Structure in Ku Band

提出了一种宽带高增益频率扫描天线阵列,通过引入周期性平面环形缝隙结构,实现了频扫天线阵列的高增益和宽带宽。由于阵列设计采用了基片集成波导背腔,且具有紧凑的结构,增益比较高。为了拓宽阻抗带宽,提高增益平整度,在单元内部引入截断八边形内贴片的环形槽结构。为了研究其工作原理,对天线单元的色散曲线进行分析和讨论。此外,分析单元数量对增益的影响,并设计了16个单元的天线阵进行验证。测量结果表明,天线实现了14.7~19.1 dBi的高增益,且宽带阻抗带宽达到11.2~18.9 GHz(51.2%),波束扫描范围为51°(-24°^+27°),测量结果与仿真结果吻合较好。该天线具有体积小、带宽宽、增益高等优点,可应用于雷达和无线通信系统。

A high gain FSA(Frequency Scanning Antenna)array with broad bandwidth is proposed.Periodic planar annular slot structure is introduced to realize high gain as well as broad bandwidth for FSA array.Since SIW(Substrate Integrated Waveguide)back cavity is adopted for array design,the gain value is much higher than conventional FSAs when considering such compact structure.The annular slot structure with truncated octagon inner patch is introduced to broaden impedance bandwidth and improve gain flatness.In order to explore the working principle,both dispersion curve and equivalent circuit of antenna element are analyzed and discussed.In addition,parameter analysis like the influence of element quantity on gain value is made in this article.The proposed antenna array of 16 elements is fabricated for verification.The measured results show that high gain of 14.7~19.1 dBi,broad impedance bandwidth of 11.2~18.9 GHz(51.2%)and beam scan range of 51°(from-24°to+27°)are achieved.Measured results are in good agreement with the simulated ones.For its advantages of compact size,wide bandwidth and high gain,the proposed antenna can be used in certain scenarios of radar and wireless communication systems.