Wireless technology appeared in 1897. Italian inventor Guglielmo MarcheseMarconi used radio signals to provide continuous communication between ships traveling on the English Channel. Since then, much attention has been paid to radio technology. The earliest public wireless system appeared after World War II. In the 1970s, the cellular system created by Bell Laboratories in the USA changed the structure of the traditional large-area system, solved the problem of frequency reuse, increased the system’s capacity and laid the foundation for the commercial use of mobile communications.