21-08-2014, 03:23 PM
4G also known as beyond 3G is an abbreviation for FOURTH-GENERATION. It is a term used to describe the next complete evolution in wireless communication. A 4g system will be able to provide a comprehensive IP solution where voice, data and streamed multimedia can be given to user on “Anytime, Anywhere” basis, and at higher data rates than previous generations.
As the second generation was a total replacement of first generation networks and handsets and the third generation was a total replacement of second generation networks and handsets so too the forth generation cannot be an incremental evolution of current 3rd generation technologies, but rather the total replacement of the current 3g networks and handsets. The international telecommunications regulatory and standardization bodies are working for commercial deployment of 4g networks roughly in 2012-2015 time scale. There is no formal definition for what is 4G.however there are certain objectives that are projected for 4G.these objectives include 4G will be fully IP-based integrated system.
Fourth generation wireless system is a packet switched wireless system with wide area coverage and high throughput. It is designed to be cost effective and to provide high spectral efficiency. The 4g wireless uses Orthogonal Frequency Division Multiplexing (OFDM), Ultra Wide Radio Band (UWB), and Millimeter wireless. Data rate of 20mbps is employed. Mobile speed will be up to 200km/hr. The high performance is achieved by the use of long term channel prediction, in both time and frequency, scheduling among users and smart antennas combined with adaptive modulation and power control. Frequency band is 2-8 GHz. it gives the ability for world wide roaming to access cell anywhere. 4G will be capable of providing between 100mbits/s and 1gbits/s speeds both indoors and outdoors with premium quality and high security.