3G TECHNOLOGY

Marconi’s innovative perception of electromagnetic waves and the air interface in 1897 was the first milestone on the important road to shared use of the radio spectrum. But only after almost a century later did mobile wireless communication start to take off. Despite a series of disappointing false starts, communication world in the late 1980’s was rapidly becoming more mobile for a much wider segment of communication users than ever before. With the advent of wireless technology, a transition from point-to-point communication toward person to-person communication (i.e.; independent of position) has begun. Testimony to this is the rapidly increasing penetration of cellular phones all across the world. In anticipation of the growing consumer demands, the next generation of wireless systems endeavors to provide person-to-person communication of the circuit and packet multimedia data.

The first generation cellular networks, which were based on analog technology with FM modulation, have been successfully deployed since the early and mid 1980’s. A typical example of a first generation cellular telephone system ( 1G ) is the Advanced Mobile Phone Services ( AMPS) . Second generation ( 2G ) wireless systems employ digital modulation and advanced call-processing capabilities. In view of the processing complexity required for these digital systems, two offered advantages are the possibility of using spectrally efficient radio transmission schemes such as Time Division Multiple Access ( TDMA ) or Code Division Multiple Access (CDMA ), in comparison to the analog Frequency Division Multiple Access ( FDMA ) schemes previously employed and the provision for implementation of a wide variety of integrated speech and data services such as paging and low data rate network access. Examples of 2 G  wireless systems include the Global System for Mobile communication ( GSM ), TDMA IS-54/IS-136 and Personal Digital Cellular ( PDC ).

Third Generation ( 3G ) wireless systems will evolve from mature 2Gnetworks with the aim of providing universal access and global roaming. More important these systems are expected to support multi dimensional (multi-information media, multi-transmission media, and multi-layered networks) high-speed wireless communication- an important milestone toward achieving the grand vision of ubiquitous personal communications. Introduction of wide band packet-data services for wireless Internet up to 2Mbps will be the main attribute of 3G system.