高增益宽带两维电扫星载SAR相控阵天线设计  

Design of High-gain Wideband 2D-electronically-scanning Spaceborne SAR Phased Array Antenna

作　　者：邵晓龙 马羽 崔智 王闻炜 荣志鹏 刘世劼 SHAO Xiaolong;MA Yu;CUI Zhi;WANG Wenwei;RONG Zhipeng;LIU Shijie(Shanghai Aerospace Electronic Technology Institute,Shanghai 201109,China)

机构地区：[1]上海航天电子技术研究所,上海201109

出　　处：《无线电工程》2025年第1期129-137,共9页Radio Engineering

基　　金：十三五航天装备预先研究项目(30502020403)。

摘　　要：设计了一款高增益宽带两维电扫星载毫米波合成孔径雷达(Synthetic Aperture Radar,SAR)有源相控阵天线。天线单元采用了窄边开“八”字斜缝的脊波导缝隙天线,功分网络亦采取脊波导结构,二者通过“工”字缝隙耦合,使得该天线阵列具有宽工作频段、低剖面的特点。为了解决700 MHz大瞬时带宽两维扫描时SAR天线波束色散问题,馈电网络中引入了最小延时步进为0.5λ_(0)和最大延时量为30.5λ_(0)的四通道延时组件,通过合理布局和链路设计弥补指向偏差。在方位向,波导缝隙天线组成直线阵,实现了方位向±3°的扫描。在距离向,波导缝隙直线阵紧密排布,通过T/R组件调节幅相,实现了距离向±45°的扫描。设计的天线包含11个天线模块,每个模块均包含7个子阵,有效口径约为176λ_(0)×31.5λ_(0)。实测天线工作频段为X波段,工作瞬时带宽为700 MHz,色散精度控制在±0.1°内,具有高增益、宽瞬时带宽、两维电扫的优点,结构简洁紧凑,适用于星载SAR系统。A 2D-electronically-scanning millimeter wave active phased antenna array for spaceborne Synthetic Aperture Radar(SAR)is presented,showing high-gain and wideband performance.The antenna element adopts the ridge waveguide slot antenna with inverted-splayed-shaped slot in the narrow edge,while the power division network also adopts the ridge waveguide.These two parts of the antenna array are coupled through I-shape slot,thus achieving the wideband and low-profile characteristics.The four-channel delay component in the feeding network provides the minimum delay step of 0.5λ_(0)and the max delay amount of 30.5λ_(0),which solves the beam dispersion of 2D-electronically-scanning SAR antenna caused by 700 MHz wide instantaneous bandwidth.In the azimuth direction,the linear array is composed of several waveguide slot antennas,and the scanning within a range of±3°in the azimuth direction is achieved.In elevation direction,the waveguide slot linear arrays are tightly arranged and the amplitude and phase are adjusted by T/R components,so as to realize the scanning within a range of±45°in the elevation direction.The final design includes eleven antenna modules and each module can be divided into seven subarrays.The effective aperture is 176λ_(0)×31.5λ_(0).Moreover,this antenna array works at X-band,and its measured instantaneous bandwidth is 700 MHz,and the dispersion accuracy is controlled within±0.1°.This antenna array has the advantages of high gain,wide instantaneous bandwidth and two-dimension electronic scanning.Meanwhile,the structure is simple and compact,which is suitable for spaceborne SAR system.

关 键 词：X波段 星载合成孔径雷达天线 宽瞬时带宽 两维电扫 

分 类 号：TN82[电子电信—信息与通信工程]