3G Networks

The year 1980 observed the first commercial mobile networks. This was based on analog communication in the radio path and was termed as first generation network (1G). 1G network were confined to national boundaries. In 1990, second generation (2G) networks came with the replacement of analog networks with the digital second generation networks. The most popular 2G technology is GSM- Global System for Mobile communication. The specification of GSM was developed in the year 1989 by the European Telecommunication Standards Institute (ETSI). The 2G technology employed by Japan was PDC- Personal Digital Communication. The main limitation of 2G networks are low transfer rates, low efficiency for packet-switched services and multiple standards. Modification of 2G resulted in 2.5 Generation networks which include High Speed Circuit-Switched Data (HSCSD), General Packet Radio Services (GPRS) and Enhanced Data rates for Global Evolution (EDGE). Third generation partnership program (3GPP) emerged in the year 1998. Here a mobile competence centre has been established to ensure day-to-day running of the 3GPP. Both frequency division duplex (FDD) mode and time division duplex (TDD) mode are employed in the access network which is based on Universal Terrestrial Radio Access (UTRA) radio interface.