针对传统微带天线频带窄，增益低等不足，通过在天线的辐射贴片和接地板上分别刻蚀花型和十字交叉缝隙图案，设计并制作了一种基于超材料的宽频带定向性微带天线。刻有图案的金属贴片和接地板间形成电容感应等效回路并改变了天线电磁场的辐射方向。天线电磁场的辐射方向主要集中在水平-x方向而不是传统微带天线的垂直方向。相比传统微带天线，该设计天线的性能得到明显改善。仿真结果表明：天线的工作带宽为3.5~11.6 GHz （是传统微带天线的23.8倍），相对带宽为107.3%，在整个频段内天线的电压驻波比小于2，增益均大于5 dB。测试结果表明：设计天线的工作带宽为2.82~12.69 GHz （是仿真模型的1.22倍），相对带宽为127.3%。该设计天线可广泛地用于弹载天线，炮瞄雷达，卫星通信网络、汽车雷达等。
In view of the narrow band and low gain in the traditional microstrip antenna, by etching flower gaps and cross strip-line gaps on the radiation patch and ground plane, respectively, a broadband and directional microstrip antenna based on metamaterials is designed and fabricated. A capacitive-inductive (C-L) equivalent circuit is produced between the patterned metal patch and the ground plane, and changes the radiation direction of the antenna electromagnetic field. The direction of the antenna radiation electromagnetic field is mainly concentrated in the horizontal -x direction rather than the vertical direction traditional microstrip antenna. Compared with the traditional microstrip antenna, the performance of the designed antenna is obviously improved. The simulation results show that the working bandwidth of the antenna is 3.5~11.6 GHz (it is 23.8 times wider than the traditional microstrip antenna), the relative bandwidth is 107.3%. The voltage standing wave ratio (VSWR) of the antenna is less than 2 in the whole frequency band and the gain is greater than 5dB. The measured result shows that the working bandwidth of the fabricated antenna is 2.82~12.69 GHz (it is 1.22 times wider than the simulation one), the relative bandwidth is 127.3%.The designed antenna can be widely used in missile borne antenna, gun pointing radar, satellite communication network, automobile radar and so on.
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