Anto vinoth.M, Punith Maharishi.Y.R
Mobile communication is continuously one of the hottest areas that are developing at a booming speed, with advanced techniques emerging in all the fields of mobile and wireless communications. With this rapid development it is expected that fourth generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existing wireless technologies. This contrasts with 3G, which merely focuses on developing new standards and hardware. 4G systems will support comprehensive and personalized services, providing stable system performance and quality service. "4G" doesn't just define a standard; it describes an environment where radio access methods will be able to interoperate to provide communications sessions that can seamlessly "hand-off" between them. More than any other technology, 4G will have a profound impact on the entire wireless landscape and the total value chain. This paper focuses on the vision of 4G and briefly explains the technologies and features of 4G.
Mobile communications and wireless networks are developing at an astounding speed. The approaching 4G (fourth generation) mobile communication systems are projected to solve still-remaining problems of 3G (third generation) systems and to provide a wide variety of new services, from high-quality voice to high-definition video to high-data-rate wireless channel. 4G can be defined as MAGIC—Mobile multimedia, anytime anywhere, Global mobility support, integrated wireless solution, and customized personal service. 4G is used broadly to include several types of broadband wireless access communication systems along with cellular telephone systems. The 4G systems not only will support the next generation of mobile service, but also will support the fixed wireless networks. The 4G systems will interoperate with 2G and 3G systems, as well as with digital (broadband) broadcasting systems and IP-based one. The 4G infrastructure consists of a set of various networks using IP (Internet protocol) as a common protocol so that users are in control because they will be able to choose every application and environment. 4G mobile data transmission rates are planned to be up to 20 megabits per second. Evaluation:
• Traditionally, wireless systems were considered as an auxiliary approach that was used in regions where it was difficult to build a connection by wire line. • 1G was based on analogy technique and deployed in the 1980s. It built the basic structure of mobile communications and solved many fundamental problems, e.g. cellular architecture adopting, multiplexing frequency band, roaming across domain, non-interrupted communication in mobile circumstances, etc. Speech chat was the only service of 1G. • 2G was based on digital signal processing techniques and regarded as a revolution from analogy to digital technology, which has gained tremendous success
• during 1990s with GSM as the representative. The utilization of SIM (Subscriber Identity Module) cards and
• support capabilities for a large number of users were 2G’s main contributions • 2.5G extended the 2G with data service and packet switching methods, and it was regarded as 3G services for 2G networks. Under the same networks with 2G, 2.5G brought the Internet into mobile personal communications. This was a revolutionary concept leading to hybrid communications. • 3G is deploying a new system offer multimedia transmission, global roaming across a cellular or other single type of wireless network, and bit rates ranging from 384 Kbps to several Mbps. Based on intelligent DSP techniques, various multimedia data communications services are transmitted by convergent 3G networks. 3G still leaves some unsolved problems that it does not concern or concerns only partly.