一种用于宽角扫描共口径相控阵的高性能天线单元

A high performance antenna element for wide-angle scan shared-aperture phased array applications

为了满足毫米波高密度、宽角扫描共口径相控阵天线对高性能、紧凑型天线单元的需求,提出了一种宽带Ku/Ka共口径天线单元设计方案.Ku频段双极化天线采用“十”字形贴片作为辐射体,一对正交放置的缝隙用于激励两个正交工作模式.Ka频段天线为探针馈电的磁电偶极子天线,加载的4个小贴片起调节匹配和方向图的作用.同时,Ka频段天线对Ku频段天线起寄生加载作用,在有效降低Ku频段天线谐振频率的同时扩展阻抗带宽.仿真结果表明,Ku频段天线水平和垂直极化分别工作在14.4~17.6 GHz和14.4~17.4 GHz,-10 dB阻抗带宽分别为20%和18.7%;Ka频段天线工作在30~40GHz,-10dB阻抗带宽大于28.5%,测试结果与仿真结果吻合良好.所提出的共口径天线单元具有尺寸小、带宽宽的特点,其横向尺寸为8.5 mm×8.5 mm(0.45λ×0.45λ,λ为Ku频段中心频率16GHz对应的波长).本文为高密度、宽角扫描共口径相控阵天线提供了新颖的天线单元设计方案.

In order to meet the demond on high-performance,compact antenna elements for millimeter-wave high-density wide-angle scan shared-aperture phased array applications,a novelty design approach of broadband shared-aperture antenna element was proposed.A cross-shaped patch is utilized as the radiator of the dual-polarized antenna element operating in Ku-band,and a pair of orthogonal slots are utilized to feed the cross patch so as to produce two orthogonal modes.A probe-fed magneto-electric dipole is utilized as the Ka-band antenna element.Herein,four parasitic small patches are loaded on the top layer to improve the impedance matching and radiation patterns.Meanwhile,the Ka-band element acts as a parasitic loading that surrounds the Ku-band element,which could effectively reduce the resonance frequency of the Ku-band element and simutaneously expand the impedance bandwidth.The simulated results show that the Ku-band element matches well in the frequency range of 14.4–17.6 GHz and 14.4–17.4 GHz for the horizontal and vertical polarization,respectively,with-10 dB fractional impedance bandwidth of 20%and 18.7%.Ka-band antenna works at 30–40 GHz,and has a-10 dB impendance bandwidth of 28.5%.The measured results are in good agreement with the simulated ones.The shared-aperture antenna element is characterized by compact size and wide bandwdith.The transverse size of proposed antenna is 8.5 mm×8.5 mm(0.45λ×0.45λ,whereλis the wavelength at center frequency of Ku band).Therefore,the developed antenna could serve as a novel antenna element for high-density,wide-angle scan shared-aperture phased array applications.