4G is fourth generation standard for mobile phones and telecommunication. It is preceded by 3G. 4G designer has been facing some technical challenges against the requirements. Yes, 4G can meet all requirements if designer overcome the challenges.
Data in 4G traffic is centric, data traffic channel increase instead of voice traffic channels. In wireless link user demand for services with the implementation of Asymmetric Digital Subscriber Line (ADSL) and fiber optic access system. System designer for wireless communication system need to cope the problemS how to increase the number of user and services that are supported in limited radio frequency bandwidth in define area.
This requirement can be achieved if system design engineers overcome the problem of bandwidth efficiency by increasing the data transmission rate and capacity to use multi-level modulation and demodulation, instead of increasing the radio frequency bandwidth. Higher data rate can be achieved from 100Mbps to 1Gbps. Low transfer delay time to 50ms or even lower then 500ms ensure the throughput for communication between the terminals.
4G have high capacity requirements by using orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), multi carrier FDMA (MC-FDMA), inter leaved FDMA advance antennas.
Technical challenge face for this requirement is increase in cost which cause commercial success of 4G impossible. In case to gain high capacity, cost increase by using higher frequency band in which result coverage area per base station reduce. In order to maintain the coverage area, must increase the number of base station. Modulation and demodulation technique, adaptive antenna, low noise receivers are circuit technologies that are used in cell radii, cell radii expand to avoid this problem.
4G support the handoff and seamless connectivity in heterogeneous networks. For 4G popularity and commercial success, smoothly replace wireless standards