物理学报
物理學報
물이학보
2015年
9期
094102-1-094102-10
,共1页
李文强%曹祥玉%高军%赵一%杨欢欢%刘涛
李文彊%曹祥玉%高軍%趙一%楊歡歡%劉濤
리문강%조상옥%고군%조일%양환환%류도
超材料吸波体%波导缝隙阵列天线%雷达散射截面
超材料吸波體%波導縫隙陣列天線%雷達散射截麵
초재료흡파체%파도봉극진렬천선%뢰체산사절면
metamaterial absorber (MA)%waveguide slot array antenna%radar cross section (RCS)
提出利用超材料吸波体减缩波导缝隙阵列天线带内雷达散射截面的设计方法.设计具有超薄(厚度仅为0.01λ,λ为吸波体中心频率对应波长)、无表面损耗层和高吸波率的超材料吸波体,将其加载到波导缝隙天线E面方向辐射缝隙间的金属表面上,并与辐射缝隙保持一定的间距.该加载方式没有破坏天线的口径馈电振幅分布,并利用超材料吸波体对电磁波的强吸收特性降低了天线阵的结构模式项散射.仿真和实验结果表明,加载超材料吸波体后天线阵的反射系数、增益、波瓣宽度保持不变,在x极化和y极化条件下,波导缝隙阵列天线的带内雷达散射截面减缩量均在6 dB 以上,且在?25?—+25?范围内天线雷达散射截面均有明显的减缩,鼻锥方向减缩超过10 dB.该研究成果对阵列天线雷达散射截面减缩具有重要的借鉴意义和工程应用价值.
提齣利用超材料吸波體減縮波導縫隙陣列天線帶內雷達散射截麵的設計方法.設計具有超薄(厚度僅為0.01λ,λ為吸波體中心頻率對應波長)、無錶麵損耗層和高吸波率的超材料吸波體,將其加載到波導縫隙天線E麵方嚮輻射縫隙間的金屬錶麵上,併與輻射縫隙保持一定的間距.該加載方式沒有破壞天線的口徑饋電振幅分佈,併利用超材料吸波體對電磁波的彊吸收特性降低瞭天線陣的結構模式項散射.倣真和實驗結果錶明,加載超材料吸波體後天線陣的反射繫數、增益、波瓣寬度保持不變,在x極化和y極化條件下,波導縫隙陣列天線的帶內雷達散射截麵減縮量均在6 dB 以上,且在?25?—+25?範圍內天線雷達散射截麵均有明顯的減縮,鼻錐方嚮減縮超過10 dB.該研究成果對陣列天線雷達散射截麵減縮具有重要的藉鑒意義和工程應用價值.
제출이용초재료흡파체감축파도봉극진렬천선대내뢰체산사절면적설계방법.설계구유초박(후도부위0.01λ,λ위흡파체중심빈솔대응파장)、무표면손모층화고흡파솔적초재료흡파체,장기가재도파도봉극천선E면방향복사봉극간적금속표면상,병여복사봉극보지일정적간거.해가재방식몰유파배천선적구경궤전진폭분포,병이용초재료흡파체대전자파적강흡수특성강저료천선진적결구모식항산사.방진화실험결과표명,가재초재료흡파체후천선진적반사계수、증익、파판관도보지불변,재x겁화화y겁화조건하,파도봉극진렬천선적대내뢰체산사절면감축량균재6 dB 이상,차재?25?—+25?범위내천선뢰체산사절면균유명현적감축,비추방향감축초과10 dB.해연구성과대진렬천선뢰체산사절면감축구유중요적차감의의화공정응용개치.
A method of reducing the in-band radar cross section (RCS) of waveguide slot array antenna by utilizing a metama-terial absorber (MA) is presented. A novel ultra-thin (the thickness is only 0.01λ,λis the wavelength corresponding to the MA resonant frequency) MA with high absorptivity and no surface lossy layer is designed;the absorber is composed of two metallic layers separated by a lossy dielectric spacer. The top layer consists of an etched oblique cross-gap patch set in a periodic pattern and the bottom one is a solid metal. Effective impedance of MMA will match the free space impedance by adjusting the dimensions of electric resonant component and magnetic resonant component in the unit cell, and so the reflection will be minimized. Meanwhile, the MMA can obtain a resonant loss to fulfill the high absorption. By finely adjusting the geometric parameters of the structure, we obtain the MA with absorption 99.9%, and its absorbing mechanism being interpreted by analyzing surface current, surface electric field, and volume power loss density distri-bution, respectively. The metallic area between slots in E plane direction of waveguide slot array antenna is covered by MA, and a distance between the radiating slot and the MA is suitably arranged. Antenna radiation performance is kept in good order because this arrangement does not destroy the amplitude distribution of antenna aperture, and the high absorptivity of MA that contributes the reduction of structure mode scattering. Simulation and experimental results demonstrate that the array antenna loaded with MA gets more than 6 dB RCS reduction both in the x-and y-polarized incident conditions; and the RCS of antenna has obviously a reduction from ?25? to +25?, the most reduction value exceeds 10 dB in the boresight direction, while the reflectance, gain and beam width are guaranteed. This idea has an important significance and engineering application for the RCS reduction of array antenna.