PRESENTED BY:-
NIKIHL NILAKAR

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4G WIRELESS SYSTEM
WHAT IS 4G ?
4G is the next major generation of mobile cellular systems, to be deployed around the year 2010.
A VIEW OF 4G :-
1) Domain of 4G extends beyond 1G, 2G, and 3G
> 2 Mbps in a wide-area mobile system (> 20 Mbps peak)
2) Could coexist with 2G and 3G
3) 4G is not necessarily defined by the bit rate, but by a significant advance in system capability beyond what can be achieved with 3G
SOME KEY CHALLENGES
Coverage
Transmit power limitations and higher frequencies limit the achievable cell size
Capacity
Current air interfaces have limited peak data rate, capacity, and packet data capability
Spectrum
Location and availability are key issues
Lower carrier frequencies (< 5 GHz) are best for wide-area coverage and mobility
4G SYSTEM RESEARCH AREAS
4G AIR INTERFACE CHARACTERISTIC
1) Higher bit rates than 3G (20 Mbps < peak < 200 Mbps)
2) Higher spectral efficiency and lower cost per bit than 3G
3) Air interface and MAC optimized for IP traffic (IPv6, QoS)
3) Higher frequency band than 3G (below 5 GHz preferred)
4) RF channel bandwidths of 20-100 MHz
5) Smaller cells, on average, than 3G
ADVANTAGE OF THIS :-
MORE SECURE
MORE FLEXIBLE
MORE RELIABLE
PROVEN TECHNOLOGY
EASIER to STANDARDIZE
EXTENSIBLE
CLOSING
4G still in a formative stage (commercial 2010)
Frequency bands less than 5 GHz preferred for wide-area, mobile services
4G system bandwidth between 20 and 100 MHz (paired or unpaired)
ITU Working Group 8F beginning to consider the requirements and spectrum needs
International 4G spectrum harmonization