The Road Towards 6G

The mobile telecommunications industry dates back to the first generation (1G) analog cellular systems represented by Advanced Mobile Phone System in the United States and Nordic Mobile Telephone in Europe, which offered voice calling services for the first time in 1980. Although there are several competing systems, the global Global System for Mobile (GSM) system has been a great commercial success and enables more than one billion of the world's population to enjoy the convenience offered by mobile voice, short text messaging, and low-speed data services. Leveraging a revolutionary technology known as Code Division Multiple Access (CDMA), the third generation (3G) systems represented by WCDMA, CDMA2000 and TD-SCDMA were first developed and deployed in 2001 to support high-speed data access at several megabits per second.