利用光子晶体可以抑制基板表面波传播来提高天线增益的基本思想,改进设计了一种高增益多层耦合贴片天线。天线采用悬置耦合馈电方式,使馈电电路与辐射元分离,减小了馈电电路对辐射元性能的影响,从而便于在阵列中的应用,同时,通过在覆盖层加载基底钻孔型PBG结构,使单元天线增益可以达到11.54 dB,相比普通单层微带贴片天线,增益提高了8.68dB。在此基础上,采用均匀等辐并联馈电网络,实际制作并测试了一个4×4元高增益微带贴片平面天线阵。测试结果表明:天线阵在12.0-13.0 GHz的频带内均满足驻波比小于2.0(VSWR〈2.0);在中心频率12.5 GHz处,天线阵增益可以达到22.23 dB,副瓣电平小于-13.5dB,相对于普通4×4元微带贴片天线阵,增益提高了近一倍,这样的结构在平面天线阵小型化领域应用前景广阔。
Based on the idea that PBG can restrain the promulgating of surface wave in substrate,a novel patch antenna is designed with multi-layer in order to enhance the gain.Through loading the PBG structure,11.54 dB gain of element can be achieved.Compared to the patch antenna with single layer,8.68 dB is increased.Then a planar array fed by parallel net with 4×4 elements is manufactured and tested.The experimental results show that VSWR is less than 2.0 from 12.0 GHz to 13.0 GHz,and 22.23 dB gain can be achieved at 12.5 GHz,which is approximately doubled in comparison with the common array.Such planar array will be used extensively in the field of miniaturization for satellite reception.