随着现代无线通信技术的快速发展，圆极化天线因其在减少多径干扰方面的优势而受到越来越多的关注，并已广泛应用于无线通信、雷达、卫星通信等系统中。由于需要传输的信号频率范围较广，因此要求使用多频段或宽频带圆极化天线来实现信号的传输和接收。微带天线具有结构简单、成本低廉、加工方便、剖面低、设计灵活、易于实现多频段及宽带圆极化工作模式等优点，因而得到了广泛的应用和深入的研究。本文首先介绍了研究背景和圆极化天线的基本参数，然后论述了微带天线实现圆极化的基本技术，最后重点阐述了微带天线实现多频和宽带圆极化的几种改进技术。

With the rapid development of modern wireless communication technology, more and more attention has been paid to circularly polarized (CP) antenna because of its advantages in reducing multipath interference, and it has been widely used in wireless communication, radar, satellite communication and other systems. Because of the wide frequency range of signals to be transmitted, it is required to use multiband or wideband CP antennas to transmit and receive signals. Microstrip antenna has the advantages of simple structure, low cost, convenient processing, low profile, flexible design and easy to implement the multiband and wideband CP mode, so it has been widely used and in-depth researches. This paper first introduces the research background and the basic parameters of circular polarization antenna. Then we discuss the basic technology of microstrip antenna to achieve circular polarization, and finally expound several improved technologies of microstrip antenna to achieve multiband and wideband CP.