The Whole Circular Polarized Antenna

Antenna, as a interface device between circuits and spaces, is a very important and indispensable component of the wireless communication system. Along with the rapid development of science, technology and society, the requirement of the antenna performance becomes higher and higher. Antenna with a simple linear polarization would be difficult to meet the various needs in modern communication system. In this situation, a wide range of concerns about circularly polarized antenna is increasing. And because of its predominances, the omni-directional circularly polarized antenna is widely used in communication, telemetry, radar, electronic reconnaissance and interference, and so on. How to balance the all the characteristics to obtain the full performance of an omni-directional circularly polarized antenna is a widely concerned issue in recent years.This dissertation mainly searches the design and realization of the omni-directional circularly polarized antenna. A novel structure of a circularly polarized omni-directional antenna is discussed in theory, by simulation and experiment.In this thesis, the antenna theory and the numerical method are expounded, the basic theory and parameters of circularly polarized wave are expatiated, and the typical methods of the realization of omni-directional circularly polarized antenna are discussed, analyzed, and compared. Based on that, a novel design of an omni-directional circularly polarized antenna is proposed. The structure, parameters and performance of the proposed antenna are discussed and analyzed. The measured data of the proposed antenna agrees well with the simulated ones. S11<-20dB, Gain is about 2dB, AR is 1.4dB-4.1dB, the average AR is about 2.4dB.It could be concluded from the researches of this thesis that the proposed antenna can radiates circularly polarized wave with omni-directional pattern.