This paper discusses the key technologies in 3G/4G/5G (third generation/fourth generation/fifth generation) communication systems, and then discusses the differences in the antenna technologies adopted by them. After reading and studying a large number of papers on the key technologies of 3G/4G/5G communication system, here I make some analysis and summary of my own. With the rapid development of science and technology, mobile communication technology has undergone profound changes, from 1G to 2G, to 3G, and then to 4G and 5G. On December 4, 2013, the fourth generation of mobile communication 4G technology was officially operated in the Chinese market, which means that China's mobile communication industry has entered the 4G era. At this time, research institutes in various countries and world-renowned enterprises engaged in communication technology research have entered the research and development of the new generation of mobile communications, namely 5G (fifth generation mobile communication system).
