Background of LTE

This chapter provides a historical overview of the evolution of mobile communication from the first generation of analog cellular systems, through second generation (2G) systems such as GSM and 3G systems including WCDMA/HSPA, into 4G LTE. ITU and its activities related to IMT and IMT-Advanced are described, as is the process in 3GPP, the organization responsible for developing the GSM, WCDMA/HSPA, and LTE technical specifications.