Study On Radiation Mode Of Circular Patch Microstrip Antenna

With the development of the times and the progress of the society,the demand for wireless communication is becoming higher and higher.A high efficient and high quality communication system is particularly important.Antenna is mainly used to receive and transmit electromagnetic waves,and its performance has great influence on the communication quality of the entire communication system.The microstrip antenna is widely used in mobile satellite communication,satellite navigation,radio frequency identification and other fields due to its low profile structure and easy to realize circular polarization.In this context,the radiation modes of circular and circular microstrip antennas are analyzed and studied in this paper.According to the actual demand,a circular microstrip antenna and two ring microstrip antennas are designed according to these theories and analysis methods.Details are as follows:1.A dual-frequency circular polarization microstrip antenna is designed based on the main mode TM11 model of the circular patch microstrip antenna,the maximum radiation direction is the normal direction of the antenna.The antenna use the cascade mode to realize the dual frequency,lower antenna working at low frequency,upper antenna working at high frequency,the radiation patch of the lower microstrip antenna as the ground floor of the upper microstrip antenna.The antenna has two ports,and works in different frequency bands when the different ports are energized.The antenna uses two separate feed networks to realize the circular polarization characteristics of different frequencies.The feed network common ground with the lower microstrip antenna,and locate at the bottom of the whole antenna.2.A circular polarization microstrip antenna is designed based on the main die TM11 module of the circular ring patch microstrip antenna.The circular polarization microstrip antenna adopts the single point feed,and the circular polarization characteristics are realized through the T type power divider.The feed network is located inside the ring patch,reducing the space occupation and effectively reducing the antenna size.A parasitic patch is loaded at a distance above the antenna to extend the bandwidth of the antenna.3.A wide-band circularly polarized microstrip antenna is designed based on the main dieTM11 module and the high model TM₂₁ model of circular ring patch microstrip antenna.The antenna is a dual port antenna.Different ports of this antenna can excite different modes of the circular loops.The broad beam can be achieved with the TM11 mode excited and the conical beam can be achieved with the TM₂₁ mode excited.The circular loops working in both TM11 and TM₂₁ modes have parasitic patches to broaden the impedance bandwidths.All three antennas have been processed and tested.The test results are in accordance with the simulation results.The first antenna and the second antenna have been used in satellite navigation.