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Mobile System Generations

FOURTH GENERATION MOBILE SYSTEMS

n First Generation (1G) mobile systems were designed

to offer a single service, i.e., speech.
n Second Generation (2G) mobile systems were also

4G
Prof. dr Zoran Bojkovic

designed primarily to offer speech with a limited capability to offer data at low rates.
n Third Generation (3G) mobile systems are expected

to offer high-quality multi-media services and operate in different environments. 3G systems are referred to as Universal Mobile Telecommunications System (UMTS) in Europe and International Mobile Telecommunications 2000 (IMT2000) worldwide.

Short History of Mobile Technologies
Technology Design Began Implementation Service

Third Generation (3G)
Two basic proposals to handle voice and data Ericsson: Universal Mobile Telecommunications systems (UMTS) • Compatible with European GSM • Backed by ETSI and Japan Qualcom: CDMA2000 • Not compatible with GSM (cannot hand off called to GSM-based cells) • Compatible for IS-95 (supported by U.S)

1G
1970 1984

2G
1980 1991

2,5 G
1985 1999

3G
1990 2002

4G
2000 2010?

Analog voice

Higher capacity, Higher capacity, Higher capacity, Digital voice, packetized data, broadband data completely IP, SMS MMS multimedia WCDMA, CDMA2000 2 Mbps CDMA packet network Single standard

Standards Data Bandwidth Multiplexing Core Network

AMPS, TACS, TDMA, CDMA, GPRS, EDGE, NMT GSM, PDC 1.9 kbps FDMA 14.4 kbps 384 kbps

200 Mbps CDMA? Internet

TDMA, CDMA TDMA, CDMA PSTN, packet network

PSTN

PSTN

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

UMTS Main Requirements (3 Ms)
n n n

Multi-media Multi-environment Multi-operator Virtual operators

Mobile Multimedia Services
Mobile Multimedia
2M 384K Video Conference (High quality) Video Conference (Low quality)

Various Existing and Emerging Wireless Technologies
Mobile TV

Broadcast
Information Distribution Services News   Weather forecast Traffic information Mobile Radio

Internet Access

Remote medical service (Medical image)

Database Access Video Catalog shopping Video on demand -Sports -News -Movies ISDN Karaoke

WWW e-mail
Electronic Newspaper Voice Mail Electronic Publishing

64K

32K 16K
Telephone Conference

ftp IP telephony etc

pager

Sports information Leisure Information

9.6K
Telephone

2.4K 1.2K

Electronic Mail

FAX

Image Data Voice

Symmetric

Asymmetric

Multicast

Point to Point

Multi Point

Convergence of High Speed Internet & Mobility a Major Driver of Future Wireless
The Wireless Industry has grown at enormous pace over the past decade. More than a billion subscribers to cellular services are enjoying the benefits of staying connected while on the move. With the growth in Internet, a wide range of services are accessed by users through a wired infrastructure. The introduction of mobile Internet brought about by the convergence of Mobile & Internet technologies is the future objective.

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 specifically needs 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
Satellite FES

Heterogeneous Networks
Billing SIP Proxy Server Signalling Gateway ISP

Internet

IPv6 backbone IPv6
Broadcast Networks (DAB, DVB-T) DVBGSM / GPRS UMTS
IP-based IPmicro-mobility micro-

Wireless LANs

Network Selection
Most Appropriate Network Selection Criteria
Challenges: • Service Type - Data rate - QoS • Available Resources • User Context - Environment (When and Where) - Mobility - User preferences

Technologies

• Convergence/integration/inter-working of all existing and emerging fixed and mobile (wired and wireless) networks including broadcast • Simple to select and easy to use desired services • Universal and low cost terminals

IP Technology

Agent Technology Reconfigurable Technology

Quality of Service
Traffic generated by the different services will not only increase traffic loads on the networks, but will also require different quality of service (QoS) requirements (e.g., cell loss rate, delay, and jitter) for different streams (e.g., video, voice, data). Providing QoS guarantees in 4G networks is a non-trivial issue where both QoS signaling across different networks and service differentiation between mobile flows will have to be addressed.

Quality of Service
One of the most difficult problems that are to be solved, when it comes to IP mobility, is how to insure the constant QoS level during the handover. Depending on whether the new access router is in the same or some other subnetwork, we recognize the horizontal and vertical handover.

Hierarchical Layers for 4G
IP-based backbone

Quality of Service
V E R T I C A L H A N D O V E R

Global layer Regional layer National layer Local area layer Personal network layer
DAB and DVB-T

Satellite

However, the mobile terminal can not receive IP packets while the process of handover is finished. This time is called the handover latency. Handover latency has a great influence on the flow of multimedia applications in real-time. Mobile IPv6 have been proposed to reduce the handover latency and the number of lost packets. The field “Traffic Class” and “Flow Label” in IPv6 header enables the routers to secure the special QoS for specific packet series with marked priority.

2G, 3G Cellular

Wireless LANs

Wireless PANs

HORIZONTAL HANDOVER

Security
The heterogeneity of wireless networks complicates the security issue. Dynamic reconfigurable, adaptive, and lightweight security mechanisms should be developed. Security in wireless networks mainly involves authentication, confidentiality, integrity, and authorization for the access of network connectivity and QoS resources for the mobile nodes flow. AAA (Authentication Authorization Auditing) protocols provide a framework for such suffered especially for control plane functions and installing security policies in the mobile node such as encryption, decryption and filtering.

Convergence of Cellular Mobile Networks and WLANs
Benefits for Operators n Higher bandwidths. n Lower cost of networks and equipment. n The use of licence-exempt spectrum. n Higher capacity and QoS enhancement. n Higher revenue. Users
n Access to broadband multimedia services with lower

cost and where mostly needed. n Inter-network roaming.

Convergence of Mobile Communications and Broadcasting
From broadcaster point of view
n Introducing interactivity to their unidirectional point-to-

Convergence Benefits
n Broadcasters will benefit from the use of cellular mobile

systems to adapt the content of their multi-media services more rapidly in response to the feedback from customers.
n Cellular operators will benefit from offering their

multipoint broadcasting systems. That is, a broadband downlink based on DAB/DVB-T and a narrowband uplink based on 3G cellular systems. From the cellular mobile operator point of view
n Providing a complementary broadband downlink in

customers a range of new broadband multi-media services in vehicular environments.
n Users will benefit from faster access to a range of

vehicular environments to support IP-based multi-media traffic which is inherently asymmetrical.

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.

Re-configurable Technology
• In order to use the large variety of services and wireless networks, multimode user terminals are essential as they can adapt to different wireless networks by reconfiguring themselves. • This eliminates the need to use multiple terminals (or multiple hardware components in a terminal). • The most promising way of implementing multimode user terminals is to adopt the software radio approach.

An ideal software radio receiver

Re-configurable Technology
Challenges: • Regulatory and Standardisation issues • Business models • User preference profiles • Inter-system handover mechanisms and criteria • Software download mechanisms • Flexible spectrum allocation and sharing between operators

Re-configurable Technology
Benefits for • Users
- Select network depending on service requirements and cost. - Connect to any network – Worldwide roaming. - Access to new services.

Personal Mobility
In addition to terminal mobility, personal mobility is a concern in mobility management. Personal mobility concentrates on the movement of users instead of users’ terminals, and involves the provision of personal communications and personalized operating environments. Once the caller’s agent identifies user’s location, the caller’s agent can directly communicate with his agent.

• Operators
- Respond to variations in traffic demand (load balancing). - Incorporate service enhancements and improvements. - Correction of software bugs and upgrade of terminals. - Rapid development of new personalised and customised services. services.

• Manufacturers
- Single platform for all markets. - Increased flexible and efficient production.

Personal Mobility

MULTIMEDIA – Video Services
4G wireless systems are expected to deliver efficient multimedia services at very high data rates. Basically there are two types of video services: bursting and streaming video services. Streaming is performed when a user requires real-time video services, in which the server delivers data continuously at a playback rate. Bursting is basically file downloading using a buffer and this is done at the highest data rate taking advantage of the whole available bandwidth.

Applications
Virtual Presence: This means that 4G provides user services at all times, even if the user is off-site. Virtual navigation: 4G provides users with virtual navigation through which a user can access a database of the streets, buildings etc. Tele-geoprocessing applications: This is a combination of GIS (Geographical Information System) and GPS (Global Positioning System) in which a user can get the location by querying.

Applications
Tele-Medicine and Educaton: 4G will support remote health monitoring of patients. For people who are interested in life long education, 4G provides a good opportunity. Crisis management: Natural disasters can cause break down in communication systems. In today’s world it might take days or 7 weeks to restore the system. But in 4G it is expected to restore such crisis issues in a few hours.

Multiple Operators and Billing System
In today’s communication market, an operator usually charges customers with a simple billing and accounting scheme. A flat rate based on subscribed services, call durations, and transferred data volume is usually enough in many situations. With the increase of service varieties in 4G systems, more comprehensive billing and accounting systems are needed.

Multiple Operators and Billing System

It is challenging to formulate one single billing method that covers all the billing schemes involved.

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.

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