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Mobile System Generations
First Generation (1G) mobile systems were designed
to offer a single service, i.e., speech.
Second Generation (2G) mobile systems were also
designed primarily to offer speech with a limited capability to offer data at low rates.
Third Generation (3G) mobile systems are expected
to offer high-quality multi-media services and operate
in different environments.
SHORT HISTORY of MOBILE TELEPHONE TECHNOLOGIES
THIRD GENERATION (3G)
Major technologies
Bluetooth
Wireless LAN (IEEE 802.x standards) – WiFi
Short range wireless communications
Highly utilized and very popular: offices, airports, coffee shops, universities and schools
Two basic modes of operations:
-Ad-hoc networking: computers send data to one another
-Access point: sending data to the base station
Limitations of 3G
Difficulty of CDMA to provide higher data rates
Need for continuously increasing data rate and
bandwidth to meet the multimedia requirements
Limitation of spectrum and it’s allocation
Inability to roam between different services
To provide a seamless transport end-to-end
Mechanism
To introduce a better system with reduces cost
4G Concept
“The user has freedom and flexibility
to select any desired service with
reasonable QoS and affordable price,
anytime, anywhere.”
Design Objectives
Next Generation will also have specificallyneeds to resolve it’s own multiple issues
Heterogeneous networks
Access, handover
Location coordination, resource coordination
Adding new users
Support for multicasting
QoS, wireless security and authentication
Network failure backup
Pricing and billing
Heterogeneous Networks
Network Selection
Most Appropriate Network Selection Criteria
• Service Type
-Data rate
-QoS
• Available Resources
• User Context
- Environment (When and Where)
- Mobility
- User preferences
Key 4G Technologies
OFDM (Orthogonal Frequency Division Multiplexing)
SDR (Software Defined Radio)
MIMO (Multiple-input multiple-output)
Interlayer Optimization
Handover and Mobility
Benefits 
Convergence of Cellular Mobile Networks and WLANs
Benefits for Operators
Higher bandwidths, Lower cost of networks and equipment,The use
of licence-exempt spectrum, Higher capacity and Qos enhancement,
higher revenue.
Users
Access to broadband multimedia services with lower cost and here
mostly needed, Inter-network roaming.
Convergence of Mobile Communication and Broadcasting
Benefits for Operators
Cellular operators will benefit from offering their customers a
range of new broadband multi-media services in vehicular
environments.
Users
Users will benefit from faster access to a range of broadband multi-
media services with reasonable QoS and lower cost.
Wireless System Discovery
A multimode terminal attaches
to the WLAN and
scans the available
systems.
It can download
suitable software
manually or
automatically.
Applications
Virtual Presence
Virtual navigation
Tele-geoprocessing applications
Tele-Medicine and Education
Crisis management
Multimedia– Video Services
CONCLUSION
As the history of mobile communications shows
attempts have been made to reduce a number of
technologies to a single global standard.
4G seems to be a very promising generation of
wireless communication that will change the
people’s life in the wireless world.
4G is expected to be launched by 2010 and the
world is looking forward for the most intelligent
technology that would connect the entire globe.