一种共面带状线馈电的圆极化双频微带天线

A Circular Polarization Dual-Band Microstrip Antenna Fed by Coplanar Stripline

提出一种工作于2.4GHz(圆极化)和5.8GHz(线极化)的双频微带天线,由共面带状线(CPS)馈电。在菱形环中内嵌小方环实现双频工作,菱形环上槽口实现圆极化特性,背面加反射板以提高天线增益。为了实测天线性能和应用于不平衡馈电方式,还设计了CPS至微带线的巴伦。实测结果与仿真结果比较吻合,在2.4GHz与5.8GHz的S11<-10dB工作带宽分别为33.3%和17.4%,增益分别达到9.05dBi和6.59dBi,2.4GHz频点3dB轴比带宽为15.8%。该天线频带宽、增益高、结构简单、易于集成,可用于无线通信和微波输能系统的整流天线中。

A new microstrip antenna fed by a coplanar stripline（CPS） operating at dual-band is proposed,one is circular polarization and the other is linear one operating at 2.4GHz and 5.8GHz respectively.The dual-band operation is realized by a pair of small square loops in the center of the rhombic loops.The circular polarization（CP） is achieved by the slot on the external rhombic loops and the gain is improved by a reflection plane.A CPS to microstrip balun is designed to measure the antenna＇ s performances and be applied in unbalanced feed structure.Experiment results agree with simulated ones.The relative bandwidth of S11 -10dB in 2.4GHz and 5.8GHz are 33.3% and 17.4% respectively.The maximum gain are 9.05dBi at 2.4GHz and 6.59dBi at 5.8GHz respectively.The relative CP bandwidth of axial ratio 3dB at 2.4GHz is 15.8%.The antenna has characteristics of wide bands,high gain,simple structure and easy to be integrated.It can be used in wireless communication systems and rectennas of microwave power transmission system.