Thesis_A Study on 3G Mobile Technology

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A Study
On
3G Mobile Technology
By
Farjana Islam
1023CSE00179
Umme Salma Munmun
1023CSE00184
Zareen Rahman
1023CSE00187
A thesis report submitted in partial fulfillment of the requirements for
the Degree of
BACHELOR OF SCIENCE IN COMPUTER SCIENCE AND ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
MANARAT INTERNATIONAL UNIVERSITY
Date: 21-06-2014

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The thesis titled “A Study on 3G Mobile Technology” submitted by the following students has
been accepted as satisfactory in partial fulfillment of the requirements for the degree of Bachelor
of Science in Computer Science and Engineering.
Farjana Islam ID: 1023CSE00179
Umme Salma Munmun ID: 1023CSE00184
Zareen Rahman ID: 1023CSE00187
Examination held on 21-06-2014
Approved By:
BOARD OF EXAMINERS
1. Shafkat Kibria Chairman
Senior Lecturer (Supervisor)
Department of Computer Science and Engineering
Manarat International University
2. Md. Ashraful Islam Member
Associate Professor
3. Muhammad Sajjad Hussain Member
Assistant Professor & Head (Ex-Officio)
4. Sohaib Abdullah Member
Senior Lecturer
5. Md. Ali Hossain Member
Lecturer
6. Professor Dr. Md. Haider Ali Member
University of Dhaka

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DECLARATION
It is hereby declared that this thesis or any part of it has not been
submitted elsewhere for the award of any degree or diploma.
Farjana Islam
ID-1023CSE00179 Signature
Umme Salma Munmun
Zareen Rahman

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Our Parents
for their support and
encouragement

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ACKNOWLEDGEMENT
We are thankful to Almighty Allah for His blessings for the successful completion of our
thesis. We are pleased to have the opportunity to do the research named “A study on 3G
Mobile Technology”. Our heartiest gratitude, profound indebtedness and deep respect
go to our supervisor Shafkat Kibria, Senior Lecturer, Department of Computer Science and
Engineering, Manarat International University, Dhaka, Bangladesh, for his constant
supervision, affectionate guidance and great encouragement and motivation. His keen
interest on the topic and valuable advices throughout the study was of great help in
completing thesis.
We are especially grateful to the Department of Computer Science and Engineering (CSE)
of Manarat International University (MIU) for providing their all out support during the
thesis work.
Finally, we would like to thank our families and our course mates for their appreciable
assistance, patience and suggestions during the course of our thesis.

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ABSTRACT
3G communication plays an important role nowadays in communication world. It is the latest
mobile technology in bangladesh, that is currently in widespread use. The evolution of GSM
to 3G is about gradually adding more functionality, possibilities and value to the existing GSM
network. In search of high speed, fast data rate capacity and good QoS, the evolution of mobile
generation reached to 3rd generation mobile communication system. Though the CDMA was the
pioneer mobile technology in Bangladesh, GSM Network supporting EDGE is dominating the
mobile communication sector at present. Inevitably the UMTS, 3G evolution of GSM Network, is
going to be the cost effective migration towards 3G technology due to the reusability of
GSM/EDGE Network subsystem.
In this paper we define and distinguish between mobile generations basically 2G and 3G
wireless. It has some of the history for both 2G, 3G network. 2G networks were built
mainly for voice data and slow transmission. It is based on the technology known as global
system for mobile communication or in short we can say GSM. This technology enabled various
networks to provide services like text messages, picture messages and MMS. 3G technology
generally refers to the standard of accessibility and speed of mobile devices. This technology
enables use of various services like GPS (Global Positioning System), mobile television and video
conferencing. It not only enables them to be used worldwide, but also provides with better
bandwidth and increased speed. Our intension is to analyze and compare 3G networks and its
service with others and also highlight its impact on our life, society and technology. For our study
we have chosen 3G because it is new technology for Bangladesh and getting popular for its
features. We discuss the basic implementation of 3G technologies and its three standard
migration processes. In this report we focus on third generation wireless technologies where we
present the evolutionary migration path from second to third generation, challenges facing the
3G communication networks and at some of the important issues pertaining to the evolution of
mobile communication networks from GSM (Global System for Mobile Communications) to GPRS
(General Packet Radio Service) to 3G (Third Generation) and to CDMA and WCDMA. Although
there are some weeknesses in some aspects we hope our findings will contribute positively.

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CONTENT
1 Introduction 1
2 Literature Review 2
2.1 1G (1st
Generation Technology ) 2
2.1.1 History of 1G 3
2.1.2 Different Standards in 1G 4
2.1.3 Capacity of 1G 4
2.2 2G (2nd
Generation Technology ) 4
2.2.1 Standards of 2G 5
2.2.1.1 GSM 5
2.2.1.1.1 Advantages of GSM 6
2.2.1.1.2 GSM Subscribers 6
2.2.1.1.3 GSM Network Components 7
2.2.1.1.4 GSM Security 8
2.2.1.2 TDMA (Time Division Multiple Access) 9
2.2.1.3 CDMA (Code Division Multiple Access) 9
2.2.1.4 PDC (Personal Digital Cellular) 9
2.3 Evolution of GSM towards GPRS and EDGE 10
2.3.1 2.5G: GPRS (General Packet Radio Service) 10
2.3.2 2.5G GPRS: Overview System 11
2.3.3 Benefits of GPRS 12
2.3.4 Limitations of GPRS 13
2.4 2.75G: EDGE (Enhanced Data Rates for Global Evaluation) 13
2.5 3G (3rd
Generation Technology) 15
2.5.1 3G History and Background 16
2.5.2 3G Networks 16
2.5.3 3G Technology Roadmap 16
2.5.4 Overview of 3G Architecture 17
2.5.5 3G Security Architecture 18
2.5.5.1 Security Mechanism Proposed by 3GPP 19
2.5.6 IMT- 2000 20
2.5.7 3G Standards and Access Technology 21
2.5.8 Capability of 3G 21
2.5.9 3G Licensing and Status 22
2.5.10 Network Coverage 23
2.5.11 3G Uses and Features 23

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2.5.12 3G Network Disadvantages 24
2.6 3.5G Generation Technology 24
2.6.1 Applications of 3.5G 24
2.6.2 Features of 3.5G 25
2.7 4G (4th
Generation Technology) 25
2.7.1 Features of 4G Technology 25
2.7.2 How 4G Technology Works 26
2.8 GSM in Bangladesh 26
2.8.1 ICT Services in Bangladesh 27
2.8.2 Using 2G & its Application in Bangladesh 28
2.9 3G Technology in Bangladesh 29
2.9.1 Present & Future Perspectives of 3G in Bangladesh 30
2.9.2 Evolution for cellular mobile communication in 31
Bangladesh
3 2G vs. 3G 32
3.1 Difference between 2G and 3G 32
3.2 Change in Network Structure 34
3.3 Network Interfaces of 2G & 3G 35
3.3.1 Types of 2G network interfaces 35
3.3.2 Types of 3G network interfaces 37
3.4 Optimization of 2G and 3G 37
3.5 The Platforms of 2G and 3G 37
3.6 Uses and Features of 2G and 3G 38
3.7 Knowing the Different 3G/2G Types 39
3.8 Some Consequences of 3G 40
4 Migration Path and Challenges from 2G to 3G 41
4.1 The road to 3G 41
4.1.1 The 2G Networks 41
4.1.2 On GPRS 42
4.1.3 The EDGE 42
4.1.4 3G improve from 2G 43
4.2 Evolution to 3G Wireless Technologies 43
4.2.1 Initial coverage 43
4.2.2 2G to 3G: GSM Evolution 43
4.2.3 Interworking with 2G & 2G+ Wireless Networks 44
4.2.4 Migration Requirements 44
4.3 Evolution of Mobile Technologies 46
4.4 The Migration Options 47
4.4.1 GSM to UMTS 48

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4.4.1.1 HSCSD in GSM 48
4.4.1.2 GPRS in GSM 49
4.4.1.3 EDGE 49
4.4.1.4 Simultaneous Voice and Data 50
4.4.1.5 Attach procedure 50
4.4.1.6 UMTS and External IP Networks 50
4.4.2 GSM to WCDMA 51
4.4.2.1 WCDMA specifies 51
4.4.2.2 Existing 2G Infrastructure 51
4.4.2.3 Spatial Division Multiple Access 53
4.4.2.4 Rake Receivers 53
4.4.3 IS95A/B to CDMA: 2000 53
4.4.3.1 Using TD-SCDMA 55
4.4.3.2 TD-SCDMA Specifies 56
4.4.3.3 WCDMA together with TD-SCDMA 58
4.4.3.4 Valuation of CDMA Migration Path 58
4.5 Migration Challenge from 2G to 3G 59
4.5.1 About 3G licenses 59
4.5.1.1 Development & Deployment Challenges 59
4.5.2 Operator Challenges 60
4.5.3 Responsibility of Operators 60
4.5.4 Challenges of 3G in Bangladesh 61
4.5.5 Migration challenges for us 62
4.5.6 Expectations from 3G in Bangladesh 63
4.5.7 Limitation from 3G in Bangladesh 64
5 Discussion 65
6 Conclusion 68
6.1 Limitation 68
6.2 Future Work 69
References 70
Glossary 72

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LIST OF FIGURES
2. 1 The configuration before 1G technology standardizations 3
2.2 1G Cellular Phone 4
2.3 2G Cellular Phone 5
2.4 GSM Logo 6
2.5 GSM Network Architecture 7
2.6 Distribution of Security features in the GSM Network 9
2.7 GSM Evolution 10
2.8 2.5G Mobile Phone 11
2.9 2.5G GPRS Architecture 11
2.10 Applications of GPRS 12
2.11 2.75G Mobile Phone 13
2.12 2.75G Architecture 14
2.13 3G Mobile Phone 15
2.14 The road to 3G 16
2.15 3G Network Architecture 17
2.16 Structure of UMTS/IMT-2000 Radio Access Network 18
2.17 Security Architecture 19
2.18 Multiple Standards for Different Applications & Countries 20
2.19 3G Standards & Access Technology 21
2.20 3G Licensing Worldwide 22
2.21 4G Mobile Communications 25

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2.22 Change of ICT use in Bangladesh 27
2.23 Mobile Subscribers Growth in Bangladesh 28
2.24 Present & Future Perspectives of 3G in Bangladesh 30
3.1 Change in Network Structure of 2G and 3G 35
3.2 A system diagram of the key components of the platform 38
4.1 Percentage of Migration paths from 2G to 3G 42
4.2 GSM Evolution to 3G 43
4.3 Migration comparison from 1G to 3G 43
4.4 Migration Requirements for 3G 45
4.5 Improved Performance Service Roadmap 46
4.6 GSM Evolution for Data Access 47
4.7 2.5G Wireless Network 49
4.8 From user information to WCDMA signal 51
4.9 WCDMA Network Overview 52
4.10 Abbreviations Found in the WCDMA Network 52
4.11 CDMAOne Network 54
4.12 CDMA2000 Network 54
4.13 CDMA2000 Evolution to 3G 55
4.14 TD-SCDMA Architecture 56
4.15 WCDMA Paired Spectrum & TD-SCDMA Unpaired Spectrum 56
4.16 The Idea behind Smart Antennas 57
4.17 Software/hardware cost of 2G to 3G 58
4.18 Challenges with 3G 61

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LIST OF TABLES
2. 1: Properties of 2G to 2.75G 14
3.1: Difference between 2G and 3G 32
3.2: Change in network structure of 2G and 3G 34

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Chapter 1
Introduction
Cellular communication has become an important part of our daily life. Besides using cell phones
for voice communication, we are now able to access the Internet, conduct monetary
transactions, send text messages etc. using our cell phones, and new services continue to be
added. However, the wireless medium has certain limitations over the wired medium such as
open access, limited bandwidth and systems complexity. These limitations make it difficult
although possible to provide security features such as authentication, integrity and
confidentiality.
The Third generation (3G) standard is currently being pushed as the next global standard for
cellular communications. 3G is the next generation of 2G technology which has revolutionized
the telecommunication industry. Apart from increasing the speed of communication, the
objective of this technology is to provide various value added services like video calling, live
streaming, mobile internet access, IPTV, etc. on the mobile phones. These services are possible
because the 3G spectrum provides the necessary bandwidth. 3G wireless systems provides
services such as advanced value added services and video telephony. It represents the
convergence of various 2G wireless telecommunications systems into a single global system that
includes both terrestrial and satellite components. One of the most important aspects of 3G
wireless technologies is its ability to unify existing cellular standards, such as CDMA, GSM, and
TDMA, under one umbrella. The following three air interface modes accomplish this result:
wideband CDMA, CDMA2000 and the Universal Wireless Communication (UWC-136) interfaces.
Although we cannot say it new because it is already being used worldwide but it's new for some
developing countries like Bangladesh. So, we become interested to select this topic as our study.
Bangladesh has one of the lowest Internet penetration rates in South Asia 4.08% . The majority,
approximately 5.7 million users are accessing Internet using GPRS, EDGE, CDMA, WiMax,
Broadband technology provided by cellular phone companies1
. The demand for new high-speed,
reliable, wireless services is growing fast. Migration to new technology in Bangladesh was a big
challenge at a moment, but beyond all the challenges, now our country made this happen,
forwarding towards a new era of 3G. This new technology has not only enriched the experience
of using mobile phone, but also creates deep influence in the economy in Bangladesh. Our
technology has infrastructure and potential to design new applications for 3G mobile phones.
Some renowned company has been providing the service of designing & maintaining applications
to various mobile phone operators in Bangladesh. For the making & maintaining 3G environment
in Bangladesh there will be an employment facility for many IT professionals. So, definitely this
technology does have a good business prospect in Bangladesh.
This study intended at analyzing the comparison between 2G and 3G (detail in 3rd
chapter), the
migration from 2G to 3G (in 4th
chapter), the usage of new 3G mobile services like high speed
internet, mobile device features and services, like video calling, online TV, etc.(in 2nd
chapter).
1
Strategic Priorities of Digital Bangladesh: EQUITABLE CITIZENS’ ACCESS -
http://www.apc.org/en/blog/strategic-priorities-digital-bangladesh-equitable-

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Chapter 2
Literature Review
It's hard to believe nowadays, but in a simpler time, cell phones really were called "cell phones,"
not dumb phones, smart phones, feature phones, or super phones. They bulged in our pocket if
they fit in our pocket at all, that is and they made calls. They were not capable of doing social
networking, messaging, browsing easily, didn't upload 5 megapixel photos to Flickr, and they
most certainly didn't turn into wireless hotspots. Of course, those bleak days are mercifully
behind us now -- but as carriers around the world start to light up a promising new generation of
high-speed wireless networks, things are beginning to get a little confusing. We take a little walk
through wireless past, present, and future, but we think it's a walk we'll enjoy.
In this chapter, we will discuss about different generations of mobile technology. GSM stands for
global system for mobile communication. The GSM system is the most widely used cellular
technology in the world today. The GSM cellular technology had a number of design aims when
the development started: Global System for Mobile Communications and IS-95 were the two
most prevalent 2G mobile communication technologies in 2007. We will also discuss about
CDMA(Code-division multiple access), TDMA(Time-division multiple access), FDMA(Frequency-
division multiple access) which are also parts of GSM technology.
 It should offer good subjective speech quality
 It should have a low phone or terminal cost
 Terminals should be able to be handheld
 The system should support international roaming
 It should offer good spectral efficiency
 The system should offer ISDN compatibility
Its success and the growth of demand for online information via the internet prompted the
development of cellular wireless system with improved data connectivity, which ultimately lead
to the third generation systems (3G). In 3G, the most prevalent technologies are UMTS, WCDMA and
CDMA-2000 which will also be discussed in this chapter. 3G systems refer to the developing
technology standards for the next generation of mobile communications systems. One of the
main goals of the standardization efforts of 3G is to create a universal infrastructure that is able
to support existing and future services.
2.1 1G (1st
Generation Technology):
1G or 1st
Generation of wireless technology, mobile telecommunications, refers to the analog
“brick phones” and “bag phones” as they were first introduced for mobile cellular technology.
Analog cellular was widely considered to be wasteful of bandwidth and had extremely limited

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capabilities for data transmission, security, and location tracking. In most regions worldwide,
analog cellular has been phased out of commercial use. 1G is designed for basic voice calls. The
only kind of data transfer is analog signal exchange between phones.
2.1.1 History of 1G:
Cell phones began its journey with 1G in the 1980s with the introduction of several
groundbreaking network technologies: AMPS in the US and a combination of TACS and NMT in
Europe. Though there were several generations of mobile telephone services before these that
date all the way back to the 1950s, the trisect of AMPS, TACS, and NMT is commonly considered
to be the first generation "1G”, because they made cell phones practical to the masses for the
very first time. They were robust, reliable, and would eventually come to blanket the Entirety of
many industrialized nations around the world. Thing is, no one was thinking about data services
in the 1G days; these were purely analog systems that were conceived and designed for voice
calls and very little else. Modems existed that could communicate over these networks -some
handsets even had them built-in but because analog cellular connections were susceptible to far
more noise than conventional landlines, transfer speeds were ridiculously slow. And even if
they'd been fast, it wouldn't have really mattered; per-minute rates on AMPS networks in the 80s
made cell phones luxuries and Wall Street powerbroker business necessities, not must-haves for
the everyman.
2.1.2 Different Standards in 1G:
1G or first generation of wireless telecommunication technology consists of various standards
among which most popular were-
 Advance Mobile Phone Service (AMPS),
 Nordic Mobile Telephone (NMT),
 Total Access Communication System (TACS).
Figure 2.1: The configuration before 1G technology standardizations

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All of the standards in 1G use frequency modulation techniques for voice signals and all the
handover decisions were taken at the Base Stations (BS). The spectrum within cell was divided
into number of channels and every call is allotted a dedicated pair of channels. Data transmission
between the wire part of connection and PSTN (Packet Switched Telephone Network) was done
using packet-switched network.
Figure 2.2: 1G Cellular Phone
2.1.3 Capacity of 1G:
The first generation (1G) mobile communications technologies had limited capacity, serving only
niche markets for the military, certain government agencies and users in special industries (e.g.
loggers, construction foremen, realtors and celebrities). In the 1960s and 1970s, this service was
geographically limited and the mobile device was too large, so it was usually mounted in cars or
trucks; the smallest was a briefcase model. This form of mobile communications were not ready
for mass development, because of
 The limited capacity to service the general population
 The limited technology capability to cover large areas,
 The large size of the mobile device, and
 The high prices of mobile devices and tariffs.
2.2 2G (2nd
2G was the switching revolution of mobile communication from analog to digital 2G is short for
second-generation wireless telephone technology. It cannot normally transfer data, such as email
or software, other than the digital voice call itself, and other basic ancillary data such as time and
date. SMS messaging is also available as a form of data transmission for some standards. The

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main aim in the design of the 2G system was the maximization of the system capacity measured
the number of user per spectrum per unit area. Some benefits of 2G were Digital signals require
consume less battery power, so it helps mobile batteries to last long. Digital coding improves the
voice clarity and reduces noise in the line. Digital signals are considered environment friendly.
Figure 2.3: 2G Cellular Phone
The use of digital data service assists mobile network operators to introduce short message
service over the cellular phones. Digital encryption has provided secrecy and safety to the data
and voice calls. The use of 2G technology requires strong digital signals to help mobile phones
work. If there is no network coverage in any specific area, digital signals would be weak.
2.2.1 Standards of 2G:
Second generation technologies are either time division multiple access (TDMA) or code division
multiple access (CDMA). TDMA allows for the division of signal into time slots. CDMA allocates
each user to a special code for communicate over the multiplex physical channel. GSM is the
most admired standard of all the mobile technologies.
 GSM
 CDMA (Code Division Multiple Access)
 TDMA (Time Division Multiple Access)
 PDC (Pacific Digital Cellular)
2.2.1.1 GSM (Global System for Mobile Communication):
GSM-2G was the first digital wireless technology. In addition to voice, GSM supports low rates for
data services (up to 9.6 Kbps) and Short Message Services (SMS). The GSM standard recommends
the application of Gaussian Minimum Shift Keying (GMSK) modulation. GMSK was developed to
reduce susceptibility to radio noise, reduce bandwidth and limit power to increase battery life for
mobile users. These result in increased frequency reuse, better voice quality and higher data
rates. To support multiple accesses by users.GSM uses a combination of FDMA and TDMA.

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Figure 2.4: GSM Logo
However, there are drawbacks to the current GSM:
 The GSM is a circuit switched, connection oriented technology, causing inefficiency in usage
of bandwidth and resources.
 The GSM does not support high data rates, e.g. video.
 Only basic messaging services such as SMS can be supported.
 The GSM networks are not compatible with common networks like TCP/IP because of
differences in network hardware, software and protocols.
GSM is an open, digital cellular technology used for transmitting mobile voice and data services.
GSM differs significantly from its predecessors in that both signalling and speech channels are
Digital call quality, which means that it is considered as a second generation (2G) mobile phone
system.
2.2.1.1.1 Advantages of GSM:
GSM differs from the first generation wireless systems because it uses digital technology and
time division multiple access transmission methods. GSM is a circuit-switched system that divides
each 200 kHz channel into eight 25 kHz time-slots. GSM supports data transfer speeds of up to
9.6 Kbit/s, allowing the transmission of basic data services such as SMS (Short Message Service).
Another major benefit is its international roaming capability, allowing users to access the same
services when travelling abroad as at home. This gives consumers seamless and same number
connectivity in more than 212 countries. GSM satellite roaming has also extended service access
to areas where terrestrial coverage is not available.
2.2.1.1.2 GMM Subscribers:
Since GSM provides common standard, cellular subscribers can use their telephones over the
entire GSM service area, which includes all the countries around the world where the GSM
system is used. In addition, GSM provides user services such as high-speed data communication,
facsimile, Short Message Service (SMS) and Intelligent Network (IN) services such as Mobile
Virtual private Networks (MVPNs).

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2.2.1.1.3 GSM Network components:
The GSM network is divided into four systems. Each system is comprises a number of functional
units or individual components of the mobile network. The systems are:
 Subscriber Equipment (SE)
 Switching System (SS)
 Base Station System (BBS)
 The Operation and Support System (OSS)
Figure 2.5: GSM Network Architecture
In GSM the subscriber identity module (SIM) is located in the mobile and contains user-specific
information, including the identity of the subscriber, the subscriber authentication information,
and some subscriber service information.
The main purpose of the Gateway MSC (GMSC) is to query the HLR to determine the location of
the mobile; the response from the HLR indicates to the MSC where the mobile is located. The call
is then forwarded from the GMSC to the MSC serving the mobile. After subscribers sign up,
information about their phone's identity and what services they are allowed to access are stored
in a "SIM record" in the Home Location Register (HLR). Once the SIM card is loaded into the
phone and it is powered on, it will search for the nearest mobile phone mast, also called a Base
Transceiver Station or BTS. If a mast can be successfully contacted, then there is said to be
coverage in the area. Stationary phones are always connected to the same part of the phone

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network, but mobile phones can "visit" any part of the network, whether across town or in
another country via a foreign provider. Each geographic area has a database called the Visitors
Location Register (VLR) which contains details of all the local mobiles. Whenever a phone
attaches, or visits, a new area, the Visitors Location Register must contact the Home Location
Register. Every phone contains a unique identifier (different from the phone number, called the
International Mobile Equipment Identity (IMEI). When a phone contacts the network, its IMEI is
supposed to be checked against the global Equipment Identity Register to locate stolen phones
and facilitate monitoring.
2.2.1.1.4 GSM Security:
Security in GSM consists of the following aspects:
 Subscriber identity authentication,
 Subscriber identity confidentiality,
 Signaling data confidentiality, and
 User data confidentiality.
The subscriber is uniquely identified by the International Mobile Subscriber Identity (IMSI). This
information, along with the individual subscriber authentication key, constitutes sensitive
identification credentials analogous to the Electronic Serial Number (ESN) in analog systems such
as AMPS and TACS. The design of the GSM authentication and encryption schemes is such that
this sensitive information is never transmitted over the radio channel. Rather, a challenge-
response mechanism is used to perform authentication. The actual conversations are encrypted
using a temporary, randomly generated ciphering key. The security mechanisms of GSM are
implemented in three different system elements; the Subscriber Identity Module (SIM), the GSM
handset or MS, and the GSM network. The SIM contains the IMSI, the individual subscriber
authentication key (Ki), the ciphering key generating algorithm the authentication algorithm as
well as a Personal Identification Number (PIN).
The GSM handset contains the ciphering algorithm .The encryption algorithms are present in the
GSM network as well. The Authentication Center (AUC), part of the Operation and Maintenance
Subsystem (OMS) of the GSM network, consists of a database of identification and
authentication information for subscribers. This information consists of the IMSI, the TMSI, the
Location Area Identity (LAI), and the individual subscriber authentication key for each user. In
order for the authentication and security mechanisms to function, all three elements (SIM,
handset, and GSM network) are required. This distribution of security credentials and encryption
algorithms provides an additional measure of security both in ensuring the privacy of cellular
telephone conversations and in the prevention of cellular telephone fraud.

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Figure 2.6: Distribution of Security Features in the GSM Network
The figure demonstrates the distribution of security information among the three system
elements, the SIM, the MS, and the GSM network. Within the GSM network, the security
information is further distributed among the authentication center (AUC), the home location
register (HLR) and the visitor location register (VLR). The AUC is responsible for generating the
sets of RAND, SRES, and Kc which are stored in the HLR and VLR for subsequent use in the
authentication and encryption processes.
2.2.1.2 TDMA (Time Division Multiple Access):
In TDMA, radio channels are divided into a number of time slots where mobiles are allocated,
and the mobile knows the time slot to use for the duration of the call. TDMA systems can also
divide the bandwidth in smaller channels as in FDMA and these channels are divided into time
slots.
2.2.1.3 CDMA (Code Division Multiple Access):
In CDMA, all users share the same radio frequency at the same time with a technique called
spread spectrum, which involves spreading the signal over a wide bandwidth. Each user is
allocated a code or sequence, and the bit rate of the sequence is much greater than the bit rate
of the information being transmitted by the mobile. The information signal for the user is
modulated with the sequence assigned to the mobile, and at the far end, the receiver looks for
the sequence used.
2.2.1.4 PDC (Personal Digital Cellular):
Personal digital cellular is a 2G mobile phone standard developed and used voice,supplementary
services(call waiting,voice mail,three forwarding and so on).

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2.3 Evolution of GSM towards GPRS and EDGE:
GSM (Global System for Mobile Communications) networks have been deployed worldwide as
second-generation mobile communications systems. GSM is a vast, rapidly expanding and
successful technology. The initial data limitations were superseded by the release of GPRS in
2000. This packet-switched functionality allows mobile handset users to use the internet.Packet
data capabilities were added in the Release '97 version of the GSM standard by means of GPRS
(General Packet Radio Services).
GPRS is a data service that is available to users of GSM and IS-136 handsets. GPRS can be used for
all data services such as Internet browsing, WAP access, SMS and MMS. Unlike GSM, GPRS is
packet-switched; in terms of multiple users, it shares the same transmission channel only when
data must be sent. The achievable data rates in GPRS depend on the supported multi slot class.
Figure 2.7: GSM Evolution
To increase the data transmission rate and to improve network capacity, EDGE (Enhanced Data
for GSM Evolution) was introduced in Release '98. With EDGE, a new modulation scheme is
applied: 8PSK (phase shift keying), i.e. three bits per RF modulated symbol as opposed to the
original one bit per symbol in GPRS. This technology change triples the effective data rate for
EDGE, resulting in a peak date rate of 59.2 Kbit/s per time slot.
2.3.1 2.5G: GPRS (General Packet Radio Service):
2.5G, which stands for "second and a half generation" is a cellular wireless technology developed
in between its predecessor, 2G, and its successor, 3G. The term "second and a half generation" is
used to describe 2G-systems that have implemented a packet switched domain in addition to the
circuit switched domain.

23
Figure 2.8: 2.5G Mobile Phone
GPRS data transfer is typically charged per megabyte of traffic transferred, while data
communication via traditional circuit switching is billed per minute of connection time,
independent of whether the user actually is utilizing the capacity or is in an idle state.
2.3.2 2.5G GPRS: System Overview
The GPRS system can logically be divided into four main areas: Mobile Station (MS), Base Station
System (BSS), Circuit-Switched System (CSS), and Packet-Switched System (PSS). Each main area
contains different network elements with specific functionalities. A GPRS system overview is
illustrated in figure below.
Figure 2.9: 2.5G GPRS architecture

24
2.3.3 Benefits of GPRS:
There are many benefits of GPRS. These are given below:
Higher Data Rate: Users of GPRS benefit from shorter access times and higher data rates. In
conventional GSM, the connection setup takes several seconds and rates for data transmission
are restricted to 9.6kbit/s. GPRS in practice offers session establishment times below one second
and ISDN-like data rates up to several 10 Kbit/s.
Easy Billing: GPRS packet transmission offers a more user friendly billing than that offered by
circuit switched services. In circuit switched services, billing is based on the duration of the
connection. This is unsuitable for applications with burst traffic. The user must pay for the entire
airtime, even for idle periods when no packets are sent (e.g., when the user reads a Web page).
Applications: The voice mail services are proving to be the key factor for mobile operators to
keep up with new services the market demands as they represent the means to enhance
significantly the quality of the service, increase the customer base and speed up the development
of the network.
Figure 2.10: Applications of GPRS
Voice mail services will offer great benefits to the operator as well to the subscriber. To
accomplish this, the operator must stimulate traffic demand while the subscriber has to
recognize the advantages of the new features, both at work and at home. GPRS enables a variety of
new and unique services to the mobile wireless subscriber. These mobile services have unique
characteristics that provide enhanced value to customers. These characteristics are given:

25
Mobility: The ability to maintain constant voice and data communications while on the move
Immediacy: Allows subscribers to obtain connectivity when needed, regardless of location and
without a lengthy login session.
Localization: Allows subscribers to obtain information relevant to their current location. The
combination of these characteristics provides a wide spectrum of possible applications that can
be offered to mobile subscribers.
2.3.4 Limitations of GPRS:
Speed much lower in reality: The network operator will not allow all timeslots to be used by a
single GPRS user.
Sub optimal modulation: GPRS is based on a modulation GMSK (Gaussian minimum shift keying)
modulation.
Transit delay: GPRS packets are sent in all different directions to reach the same destination.
2.4 2.75G: EDGE (Enhanced Data Rates for Global
Evaluation):
EDGE is standardized by 3GPP as part of the GSM family, and it is an upgrade that provides a
potential three-fold increase in capacity of GSM/GPRS networks. The specification achieves
higher data-rates (up to 236.8 Kbit/s) by switching to more sophisticated methods of coding
within existing GSM timeslots .Further enhancements to GSM networks are provided by
Enhanced Data rates for GSM Evolution (EDGE) technology. EDGE provides up to three times the
data capacity of GPRS.
Figure 2.11: 2.75G Mobile Phone
Using EDGE, operators can handle three times more subscribers than GPRS; triple their data rate
per subscriber, or add extra capacity to their voice communications. EDGE uses the same TDMA
(Time Division Multiple Access) frame structure, logic channel and 200kHz carrier bandwidth as

26
today's GSM networks, which allows it to be overlaid directly onto an existing GSM network. For
many existing GSM/GPRS networks, EDGE is a simple software-upgrade. EDGE allows the delivery
of advanced mobile services such as the downloading of video and music clips, full multimedia
messaging, high-speed color Internet access and e-mail on the move.
Due to the very small incremental cost of including EDGE capability in GSM network deployment,
virtually all new GSM infrastructure deployments are also EDGE capable and nearly all new mid-
to high-level GSM devices also include EDGE radio technology. The Global mobile Suppliers
Association (GSA) states that, as of November 2006, there were 156 commercial GSM/EDGE
networks in 92countries, out of a total of 213 GSM/EDGE deployments in 118 countries2
.
Figure 2.12: 2.75G architecture
The family of this generation consists of 2G, 2.5G and 2.75G. The specifications of this family are
shown in the table below.
Generation Starts
from
ataD
yaiaaptC
ygalochceC rtaoagS rgSvpag apoD
kgtwcSN
2G 1990 10kbps Digital
Wireless
CDDA
TDDA
GSD
oice
Data
PSTN
2.5G 2000 200sbps GPPS Supprted
TDDAAGSD
SDS
Internet
GSD
TDDA
2.75G 2003 473kbps EDGE GSD
TDDA
DDS
Internet
WCDDA
Table 2.1: Properties of 2G to 2.75G
2
EDGE Technology An Enhancement Of GPRS/GSM Networks
http://www.itmindia.edu/images/ITM/pdf/EDGE%20Technology%20an%20Enhancement%20of%20GPRSGSM%20Ne
tworks.pdf

27
2.5 3G (3rd
3G is the next generation wireless cellular network to provide a worldwide standard and a
common frequency band for mobile networking. The International Telecommunication Union
(ITU) started the process in 1992, the result of this effort was a new network infrastructure called
International mobile telecommunications 2000 (IMT- 2000), with the 2000 signifying that this
new technology will be available in 2000, will have data rates of up to 2000 Kbps and will be in
the 2000 MHz frequency range. The following is the list of objectives that IMT-2000 aims to
receive:
 To make a wide range of services, both voice and data available to users, irrespective of
location.
 To support for advance service: Multimedia, Bandwidth on demand, high speed data.
 To provide services over a wide coverage area and for low cost.
 To provide the best quality of service (QoS) possible.
 To extend the number of services provided subject to constraints like radio transmission,
spectrum efficiency and system economics.
 To accommodate a great variety of mobile stations.
 To admit the provision of service by more than one network in any area of coverage.
 To provide a modular structure which will allow the system to start from small and simple
configuration and grow as needed, both in size and complexity within practical limits.
 Flexibility for evolution allowing for backward compatibility and to cope with any future
market discontinuity.
 Multi-environment capabilities.
 Compatibility of services with fixed network.
 In Building/Private system integration.
Figure 2.13: 3G Mobile Phone

28
2.5.1 3G History and Background:
3G has dominated the modern world in just a few years. Although the technology is relatively
new, there are already so many devices taking advantage of the functions. Anyone can use it
regardless of location, so work and leisure becomes more efficient. We have to know a little
about 3G histories to know how unique it is compared to other updates in the past. Here are
some details and applications of the technology. 3G technology is the result of research and
development work carried out by the International Telecommunication Union (ITU) in the early
1980s. 3G specifications and standards were developed in fifteen years. The technical
specifications were made available to the public under the name IMT-2000. The communication
spectrum between 400 MHz to 3 GHz was allocated for 3G.
2.5.2 3G Networks:
3G networks allow network operators to provide users a bigger range of the latest services, as it
gets bigger network capacity via heightened spectral efficiency. The included services are video
calls, wide-area wireless voice telephone and broadband wireless information, all included within
the mobile environment.
2.5.3 3G Technology Roadmap:
The key technology of 3G is CDMA/WCDMA. WCDMA based 3G mobile standard has different
version like UMTS, HSDPA, HSPA,HSPA+ and CDMA based 3G standard is CDMA2000 with
versions CDMA2000 1X, 1xEV-DO Rel.0 & 1xEV-DO Rev. A. OFDMA based LTE termed as 3G &
beyond (also termed as 4G) aims to provide extra high data rate of more than 100 Mbps.
Figure 2.14: the road to 3G

29
2.5.4 Overview of 3G Architecture:
Universal Mobile Telecommunications System (UMTS), standardized by the 3GPP, is the 3G
mobile communication technology successor to GSM and GPRS. UMTS combines the W-CDMA,
TD-CDMA, or TD-SCDMA air interfaces, GSM's Mobile Application Part (MAP) core, and the GSM
family of speech codecs. W-CDMA is the most popular cellular mobile telephone variant of UMTS
in use. UMTS, using W-CDMA, supports up to 14.0 Mbit/s data transfer rates in theory with High
Speed Downlink Packet Access (HSDPA), although the performance in deployed networks could
be much lower for both uplink and downlink connections.
Figure 2.15: 3G network architecture
3G wireless networks consist of a Radio Access Network (RAN) and a core network. The core
network consists of a packet-switched domain, which includes 3G SGSNs and GGSNs which
provide the same functionality that they provide in a GPRS system and a circuit switched domain
which includes 3G MSC (Mobile switching center) for switching of voice calls. Charging for
services and access is done through the Charging Gateway Function (CGF) which is also part of
the core network. RAN functionality is independent from the core network functionality. The
access network provides a core network technology independent access for mobile terminals to
different types of core networks and network services. Either core network domain can access
any appropriate PAN service e.g. it should be possible to access a “speech” radio access bearer
from the packet switched domain.
The Radio Access Network consists of new network elements known as Node B and Radio
Network Controllers (RNCs). Node B is comparable to Base Transceiver Station in 2G wireless
SD
Mobile Station
MSC/
VLR
Base Station
Subsystem
GMSC
Network Subsystem
AUCEIR HLR
Other Networks
Note: Interfaces have been omitted for clarity purposes.
GGSN
SGSN
BTS
BSC
Node
B
RNC
RNS
UTRAN
SIM
ME
USIM
ME
+
PSTN
PLMN
Internet

30
networks. RNC replaces the Base Station Controller. It provides the radio resource management,
handover control and support for the connections to circuit-switched and packet-switched
domains. The interconnection of the network elements in RAN and between RAN and core
network is over lub3
, lur3
and lu3
interfaces based on ATM as a layer 2 switching technology. Data
services run from the terminal device over IP, which in turn uses ATM as a reliable transport with
QoS. Voice is embedded into ATM from the edge of the network (Node B) and is transported over
ATM out of the RNC.
The lu interface is split into 2 parts: circuit-switched and packet-switched. The lu interface is
based on ATM with voice traffic embedded on virtual circuits using AAL2 (Adaptation Layer 2)
technology and IP-over-ATM for data traffic using AAL5 (Adaptation Layer 5) technology. These
traffic types are switched independently to either 3G SGSN for data or 3G MSC for voice.
Figure 2.16: Structure of UMTS/IMT-2000 Radio Access Network
2.5.5 3G Security Architecture:
As mobile networks become high speed and attain an all-IP structure, more services are possible.
This brings about many new security requirements that traditional security programs cannot
handle.. In this scheme, a trusted computing environment is constructed on the mobile terminal
side by combining software validity verification with access control.
3
lub, lur, lu – three of four interfaces connecting the UTRAN internally or externally to other functional entities.

31
2.5.5.1 Security Mechanism Proposed by 3GPP:
To secure 3G mobile telecommunication systems, 3GPP has developed as a security architecture
with five different sets of features in three strata
Figure 2.17: Security architecture
There are five different sets of features that are part of the architecture:
 Network access security: This provides users with secure access to 3G services and protects
against attacks on the radio access link. This feature enables users to securely access services
provided by the 3G network.
 Network domain security: This enables nodes in the provider domain to securely exchange
signaling data and protects against attacks on the wire line network.
 User domain security: This secures access to mobile stations.
 Application domain security:D This enables applications in the user domain and provider
domain to securely exchange messages.
 Visibility and configurability of security: This enables users to determine whether a security
feature is in operation or not and whether the use and provision of services should depend
on the security feature.
In 3GPP’s security architecture, the emphasis is on the network access security mechanism,
including mutual authentication, universal terrestrial radio access network (UTRAN) ciphering,
and integrity protection of signaling data.

32
Network access security mechanisms mainly fall into three categories:
 Identification by temporary identities such as Temporary Mobile Subscriber Identity (TMSI)
 Identification by a permanent identity such as International Mobile Subscriber Identity
(IMSI)
 Authentication and key agreement (AKA).
Among these, AKA is important and is a hot topic in research on 3G network security
mechanisms. AKA mutually authenticates the mobile station and network, creating a new cipher
key and integrity key.
2.5.6 IMT-2000:
The main characteristics of 3G systems, known collectively as IMT–2000, are a single family of
compatible standards that have the following characteristics:
 Used worldwide
 Used for all mobile applications
 Support both packet-switched (PS) and circuit-switched (CS) data transmission
 Offer high data rates up to 2 Mbps (depending on mobility/velocity)
 Offer high spectrum efficiency
Figure 2.18: Multiple Standards for Different Applications and Countries

33
2.5.7 3G Standards and Access Technology:
As mentioned before, there are several deferent radio access technologies dined within ITU,
based on either CDMA or TDMA technology. An organization called 3rd
Generation Partnership
Project (3GPP) has continued that work by dining a mobile system that falls the IMT-2000
standard. This system is called Universal Mobile Telecommunications System (UMTS). After trying
to establish a single 3G standard, ITU finally approved a family of 3G standards, which are part of
the 3G framework known as IMT-2000:
 W-CDMA
 CDMA2000
 TD-SCDMA
Europe, Japan and Asia have agreed upon a 3G standard called the Universal Mobile
Telecommunications System (UMTS), which is WCDMA operating at 2.1GHz. UMTS and WCDMA
are often used as synonyms.
Figure 2.19: 3G Mtandards and access technology
2.5.8 Capability of 3G:
It enables network operators to offer subscribers a wider range of advanced services while
achieving greater network capacity through increased bandwidth, transfer rates and spectral
efficiency.
3G networks are intended to facilitate smart phone advanced capabilities such as the following:
 High-speed data transmissions: 3G will bring an order of magnitude improvement to data
communications enabling the use of bandwidth hungry multimedia applications. Multimedia

34
and video conferencing are the services that are expected to justify the new infrastructure.3G
data rates fall into three categories.
 Symmetrical and asymmetrical data transmission support: Email and web browsing is
predominately asymmetrical. For example, data transmitted to the user is much greater than
that transmitted by the user.
 Improved voice quality: Provide voice quality comparable to that of wire-line telephony.
 Greater capacity: With the explosion in cellular phone usage, the need to efficiently use
frequency spectrum is imperative.
 Multiple simultaneous services: This allows a user to download an MP3 audio file while
talking on the same cell phone.
 Global roaming across networks: 3G is expected to support international roaming. Currently
roaming between international networks requires a different cellular phone for each
network.
 Improved security: Users will be able to communicate and conduct business in a secure
environment. This will ultimately foster additional commercial services.
 Service flexibility: Both circuit-switched (e.g. voice, real-time video) and packet-switched
services (e.g. Internet Protocol) shall be supported.
2.5.9 3G Licensing and Status:
Most GSM operators failed or missed to obtain a UMTS license, such as Denmark, France and the
United Kingdom. These are not totally counted out. Current operators have big assets, a huge
customer base, retail network, BTS site locations, image, transmission systems and several
others. These give them the advantage of making deals with license.
Figure 2.20 : 3G Liscensing worldwide

35
In the United States, a number of operators have chosen CDMAOne, CDMA2000 1x EV-DO,
CDMA2000 and CDMA2000 3X. Others have even chosen GSM1900, EDGE or D-AMPD-EDGE.
There are new cellular frequencies allocations that may have been delayed or postponed, leading
operators to use the current frequencies that naturally stop the available capacity at a certain
point.
2.5.10 3G Network Coverage:
According to the International Telecommunications Union, five technologies comprise
3G technology as a whole. These technologies include:
 Enhanced Data rates for GSM Evolution, known as EDGE,
 Code Division Multiple Access or CDMA 2000,
 Universal Mobile Telecommunications System or UMTS,
 Digital Enhances Cordless Telecommunication and
 Worldwide Interoperability for Microwave Access or WiMax.
2.5.11 3G Uses and Features:
3G was successfully launched and introduced to millions of consumers all over the globe.
However, there are still some features and uses that are still questioned by many. Knowing the
effects and details will help us to take advantage of aspects like price, functions and accessibility.
Here are some more information regarding the full uses of 3G technology:
Accessibility: Because of easy and fast accessibility, we get to enjoy data transmission speed up
to a maximum of 2 Mbps, if the individual is using the cellular phone on stationary phone. This
also gives bigger and faster data transfer rates of increased networking and connectivity. On top
of it all, we get to enjoy noise resistance. There are also greater potentials for the uses of 3G.
These are still currently being worked on by professionals.
New Technologies: 3G technology is the latest one that offers faster data transfers through
people's cellular phones. 3G stands for third generation mobile telephone communication
systems technology. People will be able to receive and transmit data at a rate of 2 Megabits for
every second. 3G cellular phones are also capable of having conventional fax, data and voice
services, plus multimedia and high-resolution video services that can be used, while they are on
mobile. Other mobile office services are included such as online-billing, online banking, access to
the internet, online entertainment and video conferencing.
Video Conferencing & Live television: One of the more known advantages of 3G technology, is
that it allows our phone's capacity to view television shows through our cellular phone. 3G
phones have become one of the most powerful devices available. People get to conduct video
conferencing if ever their flight gets delayed or they have other location problems.

36
Daily Works: We can also balance checks and pay bills and debts, by simply logging on to our
bank account via the 3G gadgets we have. People can book dinners and hotel reservations in
advance, in other cities and countries. Teleconferencing is among the most excellent applications
for 3G technology at work.
For Security: 3G provides a bigger degree of security compared to 2G predecessors. It allows the
UE to authenticate the network that it is connected to, the consumer can be certain that the
network is the right one and not impersonated.End to end security is provided aside from the 3G
network infrastructure security, when frameworks of applications like IMS are connected to,
although this is not usually a property of 3G.
2.5.12 3G Network Disadvantages:
The major disadvantage for 3G network plans centers around pricing. Generally, 3G network
price points are much higher than 2G networks with comparable features. In addition, the
allowed minutes are often set at a much lower threshold than for 2G plans of a similar price
range.
2.6 3.5 Generation Technology:
3.5G is a collection of mobile telephony protocols that extend and improve the performance of
existing UMTS protocols. It's commonly abbreviated as 3.5G to denote the high speeds that they
offer relative to standard 3G technologies. Two standards, High-Speed Download Packet Access
(HSDPA) and High-Speed Upload Packet Access (HSUPA), have been established at the moment.
HSDPA gives download speed of up to 7.2Mbps.3.5G is faster than that of 3G. It completely based
on HSPA (high speed downlink packet access).Anyone get more speed on downloading than that
of 3G case. 3.5G gives a speed of 384 kbps. The average data transfer is about 200 kb/s and in
3.5G it is around 300 kb/s
2.6.1 Applications of 3.5G:
 Video on demand
 Mobile TV
 Video Conference
 Telemedicine
 Location based Services
 Global Positioning System

37
2.6.2 Features of 3.5G:
 High-Speed Downlink Packet Access
 Evolved HSPA
 3GPP Long Term Evolution, precursor of LTE advanced
2.7 4G (4th Generation Technology):
4G stands for the fourth generation of cellular wireless standards. It is successor to 3G and 2G
families of standards. Speed requirements for 4G service set the peek download speed at
10Mbit/s for high mobility communication and 1Gbit/s for high mobility communication. It
enables seamless roaming between the technologies. One of the terms used to describe 4G is
magic-Mobile multimedia anytime, anywhere, Global mobility support, integrated wireless
solution and customized personal service. 4G system is expected to provide a comprehensive and
secure all-IP based broadband solution to smart phones, laptop computer wireless modems and
other mobile services.
Figure 2.21: 4G mobile communications
4G is around five times faster than existing 3G services. Theoretically it can provide download
speeds of up to 100Mbps. The faster speeds mean websites load quicker, and that anyone will be
able to stream videos and podcasts without first waiting for them to buffer.
2.7.1 Features of 4G Technology:
The followings are some possible features of the 4G:
 Support interactive multimedia, voice, video, wireless internet and other broadband
services.
 High speed, high capacity and low cost per bit.
 Global mobility, service portability, scalable mobile networks.
 Seamless switching, variety of services based on Quality of Service requirements
 Better scheduling and call admission control techniques.

38
The main reason, 4G is faster than 3G is because of Orthogonal Frequency-Division Multiplexing
(OFDM). It sounds complicated, but it's the same technology used in Wi-Fi, ADSL broadband,
digital TV and radio. OFDM is a technique for squeezing more data onto the same amount of
radio frequency. It also reduces latency and interference. Data is split up and sent via small
chunks of frequency in parallel, therefore increasing the capacity of the network. Multiple-input
and multiple-output, or MIMO, is another reason 4G is able to provide faster speeds. It is simply
the use of multiple antenna arrays at both the transmitter and receiver to improve
communication performance. This allows more data to be transferred without requiring
additional bandwidth or drawing more power.
2.7.2 How 4G Technology Works:
As the need that of communication rather fastest communication is the foremost priority of present era
also that need in a quick data transfer. Distant business it correspondence by sharing data it becomes very
important and ever growing technology is the example of one such step towards the fastest transmission
of data. 4G is the latest technology high speed transferability of data with a security measurement. Talking
about that the standard of 4G technology, still not be defined as set standard, two technologies are
supposed to be the based features of 4G.
1. Wi-MAX
2. LTE
1. Wi-MAX: Wimax stands for Worldwide Interoperability of a Microwave Access previously
worked as the fixed wireless facility under 802.16e band. 4G technologies likely to enable an
ubiquitous computing, that will simultaneously connects to the numerous high date speed
networks offers faultless handoffs all over the geographical regions.
2. LTE: LTE is compatible with 3G technology so it not only increases the speed but also prevents
the need of new network and it can work through the same infrastructure. LTE using MIMO
(Multiple input multiple output) able to send and receive huge data negative in the sense that it
will overload the base stations networks.
2.8 GSM in Bangladesh:
Bangladesh was the first South Asian country to adopt cellular technology back in 1993 by
introducing Advanced Mobile Phone System (AMPS). In fact, the first mobile license was issued
back in 1989 but it took several years to launch the services. The network coverage and number
of subscribers had remained very limited due to exorbitantly high subscription cost and call tariff.
In 1996, the government led by Prime Minister Sheikh Hasina, considering the monopolistic
environment prevailing in the sector, awarded three GSM licenses aimed at breaking the
monopoly and making the cellular technology affordable to the general masses.

39
Since then, the country's cellular industry never looked back, now it has turned into the largest
infrastructure provider during the last decade as sub sector within telecom sector.
In recent years, the mobile industry in Bangladesh has developed at an extraordinary rate. Today
there are approximately ten million mobile customers and coverage extends to 90% of the
population4
. The mobile communications sector in Bangladesh is one of the fastest growing
industries and has helped boost the economic and social development in the country in three
main ways:
 By providing value-added services and creating employment from direct/indirect firms
in the telecommunications sector,
 Increased productivity in businesses as a result of mobile phone usage,
 Increasing the involvement and engagement of its population with news and current
affairs.
2.8.1 ICT Services in Bangladesh:
The ICT sector in Bangladesh has grown significantly in the last two decade. The mere numbers of
internet users has grown into a mammoth 30 million in the last decade mainly due to the ease of
data connectivity using the 2.5G Network. The Figure 2.22 shows the internet user statistics in
Bangladesh.
Figure 2.22: Change of ICT use in Bangladesh
The Government has emphasized in e-governance and is in the process of facilitating the public
services over internet. The private sector is also contributing in the development of ICT services
4
Overview of Mobile Telecommunication Industry in Bangladesh
http://mushfiq009.wordpress.com/%E2%80%9Coverview-of-mobile-telecommunication-industry-in-bangladesh-
%E2%80%9D/

40
like e-commerce, mobile banking, e-health, and e-education etc. Besides, software freelancing,
remote surveillance and video conferencing services are gaining popularity resulting in increasing
demand of higher data speed connectivity.
At present the countrywide 2.5G Network is playing a vital role in providing the limited capacity
ICT services. But the low data rate of 2.5G Network is not sufficient for the increasing demand.
As such, the 3G Network capable of providing triple play services at a higher data rate is the
inevitable next big step towards the ICT development in Bangladesh.
2.8.2 Using 2G and its Application in Bangladesh:
Mobile phone is the most common and convenient medium of communication for distant
inhabitants in Bangladesh. The introduction of mobile phone has not only accelerated the
economic growth by vast marketing in the field of new business; but also made the lifestyle of
the overall population easy. A good number of operators have popularized the cellular phone
service in Bangladesh through opening a new path of communication.
GrameenPhone first started GSM in Bangladesh. After that GPRS and EDGE was started, and since
then mobile internet was so easy to use and wap users increased rapidly that time. Mobile
internet is a new trend in Bangladesh. If a person has a GPRS or EDGE enabled mobile set he can
use internet and join the world of web easily. The major advantage of mobile internet in
Bangladesh is that a subscriber can use internet from anywhere of the country where mobile
network exist.
Figure 2.23: Mobile Subscribers Growth In Bangladesh
As of June 2010, there were 60million mobile subscribers in the country, representing a
penetration rate of 37%. In 2009, according to Bangladeshi internet service providers (ISPs), there
were around 4.5 million customers who used the internet, with 90 percent of them connecting
through mobile phone operators ’ wireless modems. All the mobile phone service providers now
offer Wap and mobile internet service. GrameenPhone offers USB EDGE/GPRS internet modem

41
to use in both Desktop and Laptop computers. Citycell offers ZOOM CDMA internet modem.
Grameenphone also provide wap based contents by their wap site.
2.9 3G Technology in Bangladesh:
It is the improvement of science and technology that has made our life easier, given us immense
opportunity to access to anyone we desire. Mobile phone, a wonderful invention of modern
science, was first introduced in Bangladesh in the middle of 1990s. Now-a-days mobile phone has
become a part & parcel of our everyday life and it is quite affordable to the poor people as well.
Technology behind mobile phone has been changed several times and it’s an ongoing process. So
far mobile phones have experienced 1G, 2G, 2.5G, and 3G. 3G is one of the most talked
technologies in the present scientific world. Although developed and our neighboring countries
have been experiencing 3G for a handsome number of years, Bangladesh was not fortunate
enough to have this technology so far. After a long cherished waiting, things have been changed
as Bangladeshi telecom operator Teletalk launched 3G by 2012.
International Mobile Telecommunications-2000 (IMT 2000), better known as 3G, is a generation
of standards for mobile phones and mobile telecommunications services fulfilling specifications
by the International Telecommunication Union (ITU). Application services include wide area
wireless voice telephone, mobile Internet access, video calls and mobile TV, all in a mobile
environment. One gorgeous feature of 3G Technology is video conference application. 3G not
only ensures high speed internet but also allows the mobile phone carrier to set up call in less
time & ensures less call drop. However, with the capability for high-speed wireless data transfer,
3G has enhanced or made possible a myriad of additional applications such as mobile video,
secure mobile, location-based services, and audio on demand.
This new technology not only enriches the experience of using mobile phone, but also creates
deep influence in the market & economy in Bangladesh. As it has been mentioned earlier, 3G
mobile accessories will have to be imported from other countries as no infrastructure has been
introduced yet in our country to produce those. But we have infrastructure and potential to
design new applications for 3G mobile phones. GPIT (GrameenPhone IT), a shining example in
this regard, has been providing the service of designing & maintaining applications to various
mobile phone operators in Bangladesh. For making & maintaining 3G environment in Bangladesh
there will be an employment facility for many IT professionals. So, definitely this technology does
have a good business prospect in Bangladesh.
Though the CDMA was the pioneer mobile technology in Bangladesh, GSM Network supporting
EDGE is dominating the mobile communication sector at present. Inevitably the UMTS, 3G
evolution of GSM Network, is going to be the cost effective migration towards 3G technology due
to the reusability of GSM/EDGE Network subsystem. Accordingly as 3G technology, UMTS
Network will be referred vise verse throughout the paper in Bangladesh context.
As a government runs company, Teletalk has got the very first chance to develop its 3G structure.
It will first provide 3G coverage in Dhaka and gradually cover the whole country. Teletalk, which

42
started its service in 2005, did not gain much success in telecommunication sector. But maybe
this time, with the launching 0f 3G, Teletalk will get a chance to change its fate. After Teletalk,
other mobile service operator will get 3G license according to their demand. As 90 percent of
Bangladeshi consumer take the service from non government operators, 3G in real sense will be
experienced after they get license and make infrastructure. This will not be rhetoric to say that,
3G is going to start a new era in Telecommunication sector of Bangladesh.
2.9.1 Present and Future Perspectives of 3G in Bangladesh:
3G in Bangladesh Present and Future Perspectives is the big issue for mobile internet users. 3G
technology is brand new concept of Bangladesh and also state of art technology of mobile
communication. Speed is the great issue to use 3G services. It’s totally depends on mobile device,
coverage area, network traffic where anyone staying, number of users who currently using 3G
network at that particular time and network area. It also depends on data package speed which is
subscribed. In Bangladesh, right now most of the mobile users are confused about R99 and HSPA.
R99 is a mobile handset data bearer service up to 384 kb/s which is generally known as Release
99 or R99. HSPA means high Speed packet access. It is combination is HSUPA (High speed uplink
packet access) &HSDPA (high speed downlink packet access) that support maximum 42 Mb/s.
Figure 2.24: Present and Future Perspectives of 3G in Bangladesh

43
2.9.2 3G Evolution for cellular mobile communication in
Bangladesh:
The telecoms sector in Bangladesh has seen growth in mobile penetration that has exceeded all
expectations with over 65.1 million subscriber as of September 2010 versus only 4 million in
2004.We believe with a supportive regulatory environment, crossing 100 million subscribers by
2014 is achievable. The rapid growth in mobile telephony has undoubtedly had a transformative
impact on the economy in terms of aggregated investment, FDI and productivity levels. There
have also been substantial benefits from greater connectivity in terms of social cohesion and
poverty alleviation.
However the industry also faces a number of uncertainties, including upcoming telecom license
renewals which expire in 2011 and prospective auction/issuance of 3G license where the cost of
the licenses are still unclear. With India’s auctions having been completed on 19 May 2010 and
service delivery under roll out process, it is believable there are number of valuable lessons for
the prospective evolution of 3G and beyond 3G markets in Bangladesh. 3G networks are
expected to significantly enhance user experience of existing data service, with the introduction
of video and other high bandwidth services by carriers; to help 3G really gain adoption among
consumers, development of a mobile VAS ecosystem is critical.
Mobile data surpassed voice on a global basis in December 2009.It is forecast that mobile
broadband users are expected to more than 3.4bn by 2015(from 360M in 2009). 80% of all
people accessing the internet will do so using their mobile device. The main divers for increased
activity on the mobile devices are three-fold network in the form of 3G, higher processing power
device being available for mass-market price, and the fact that consumers are not only
consuming but also producing content at an exponential pace. In developing market, voice
revenues are likely to continue to expand but data will also become more important.
Finally Bangladesh got license for 3G cellular mobile communication, which are provided high
data rate service and 3G video call this service is only available in Teletalk mobile service Provider
Company. It is predicting that Bangladesh may under completely 3G services within 2016.

44
Chapter 3
2G vs. 3G
2G technology is based on the technology known as global system for mobile communication.
This technology enabled various networks to provide services like text messages, picture
messages and MMS. In this technology all text messages are digitally encrypted due to which only
the intended receiver receives message. These digital signals consume less battery power. The
technologies used in 2G are either TDMA (Time Division Multiple Access) which divides signal into
different time slots or CDMA (Code Division Multiple Access) which allocates a special code to
each user so as to communicate over a multiplex physical channel.
3G technology generally refers to the standard of accessibility and speed of mobile devices. This
technology enables use of various services like GPS (Global Positioning System), mobile television
and video conferencing. It not only enables them to be used worldwide, but also provides with
better bandwidth and increased speed. This technology is much more flexible as it can support 5
major radio technologies that operate under CDMA, TDMA and FDMA. CDMA accounts for IMT-
DS (direct speed), IMT-MC (multi carrier). TDMA holds for IMT-TC (time code), IMT-SC (single
carrier).The main aim of this technology is to allow much better coverage and growth with
minimum investment.
3.1 Difference between 2G and 3G:
Feature 2G 3G
Cost The license fee to be paid for 2G
network is lower.
The license fee to be paid for 3G
network is much higher.
Data
transmission
2G is less compatible with the
functions of smart phone. The
speed of data transmission in 2G
network is less than 50,000 bits
per/s.
Faster download speeds, faster access to
the data and applications. In 2G network
the speed of data transmission is 4
million bits /s.
Function The main function of 2G
technology is the transmission of
information via voice signals.
3G technologies is data transfer via
video conferencing, MMS etc.

45
Features 2G 3G
Services Voice using and text messaging Mobile TV, video transfers and GPS
systems are the additional features of
3G technology.
Frequency 2G technology uses a broad range
of frequencies in both upper and
lower bands
3G is that it is simply not available in
certain regions.
Implication 2G technology offers a low level of
security
3G technology offers a high level of
security because 3G networks permit
validation measures when
communicating with other devices.
Switching
techniques
2G use different switching
techniques for voice and data
3G uses single switching for any kind of
data.
Security 2G is less secure than 3G 3G network is more secure than 2G
network. 3G network allows
authentication procedures when
communicating with other devices.
Global facility Only Semi global facility is available Global level with rooming facility is
available
Handsets
Capability
2G handsets don’t possess such
capabilities.
3G handsets can also work on 2G
networks
Table 3.1: Difference between 2G and 3G

46
3.2 Changes in Network Structure:
Feature 2G 3G
Core Network MSC/VLR, GMSC,
HLR/AuC/EIR
MM, CM, BSSAP, SCCP,
ISUP,TCAP, MAP, MTP 3,
MTP 2, MTP 1
3G MSC/VLR (with added
interworking and
transcoding), GMSC,
HLR/AuC/EIR, 3G-SGSN,
GGSN, CGF
GMM/SM,MM,CM,BSSAP,
RANAP,GTP,SCCP,
MTP3B, M3UA, SCTP,
Q.2630.1 (NNI), TCAP,
MAP, ISUP, MTP 3, MTP2,MTP
1,Q.2140,SSCOP
Switching Circuit Packet except circuit for air
interface
Radio Access BTS, BSC, MS
FDMA, TDMA, CDMA
MM, CM, RR, LAPDm,
LAPD, BSSAP, SCCP,
MTP 3, MTP 2, MTP 1
Node B, RNC, MS
W-CDMA, CDMA2000,
IWC-136
GMM/SM, MAC, RLC,
PDCP,RRC,Q.2630.1(UNI+
NNI),NBAP, RNSAP,
RANAP, SCCP, MTP3B,
M3UA, SCTP, GTP-U,
Q.2140, Q.2130, SSCOP,
Handsets Voice only terminals New type of terminal
Multiple modes
Voice, video terminals, WAP,
multimedia
Databases HLR, VLR, EIR, AuC Enhanced HLR, VLR, EIR AuC
Data Rates Up to 9.6 Kbps Up to 2Mbps
Applications Advanced voice, SMS Internet, multimedia
Table 3.2: Change in network structure of 2G and 3G

47
Figure 3.1: Change in network structure of 2G and 3G
3.3 Network Interfaces of 2G & 3G:
Network interface: Network Interface is a systems interface between two pieces of equipment
or protocol layers in a network. A network interface will usually have some form of network
address. This may consist of a node Id and a port number or may be a unique node Id in its own
right. Network interfaces provide standardized functions such as passing messages, connecting
and disconnecting etc.
3.3.1 Types of 2G network interfaces:
The types of interface is given below-
1. A interface
2. B interface
3. C interface
4. D interface
5. zz interface
6. 39/xx interface
7. Q interface
8. T1 interface
9. ISUP interface
A Interface: The A interface exists between the circuit switched domain of the CDMA network
subsystem (NSS) and the base station subsystem (BSS). In terms of entity, it is the interface
between the MSCe/MGW and BSC.

48
The A interface is used to transmit the following messages:
 Mobile station (MS) management messages
 Base station (BS) management messages
 Mobility management messages
 Call processing messages
B Interface: The B interface exists between MSCe and VLR. It adopts an internal protocol without
a specific signaling transmission mode. The B interface is used in the following cases:
 The MSCe obtains user messages from the VLR.
 The MSCe notifies the VLR to record location information when an MS updates its location.
 The MSCe notifies the HLR to update data through VLR when an MS activates a
supplementary service or modifies the relevant data.
C Interface: The C interface exists between the MSCe and HLR. It complies with the mobile
application part (MAP) of the SS7. The C interface is used in the following cases:
 The HLR sends routing information to the MSCe when an MS is called.
 The short message service (SMS) is implemented.
D Interface: The D interface exists between VLR and HLR. It complies with the MAP of the SS7.
The D interface is used to transmit the following messages:
 Authentication data
 Location update messages
 User data indexed during call connection
 Data of supplementary services
 VLR recovery messages
zz Interface: The zz interface exists between two MSCes. It complies with the SIP with
encapsulated ISUP (SIPI).The zz interface provides the inter-office call control function for the
narrowband circuit-switched domain services that are independent of the user plane bearer
technology and the control plane transmission technology.
39/xx Interface: The 39/xx interface exists between an MGW and a media resource function
processor (MRFP). It complies with the Megaco/H.248. The 39/xx interface is used in the
following cases:
 The MSCe controls dynamic and static resources of the transmission modes (IP/TDM) in the
MGW during call processing, including terminal attributes, terminal connectivity, and media
streams.
 The MSCe maintains and manages the status of the MGW.
Q Interface: The Q interface exists between the MSCe and the MC. It complies with the MAP of
the SS7 to support the short message service.
T1 Interface: The T1 interface exists between the MSCe and the SCP. It complies with the WIN of
the SS7 to support the intelligent network service.

49
ISUP Interface: When the MSC serves as a gateway office, it provides the interface between the
PSTN and other mobile network devices. It also controls the incoming calls and outgoing calls
through ISUP or TUP of the SS7.
3.3.2 Types of 3G network interfaces:
 Radio interface
 Air interface; are the types of 3G network interfaces.
Radio Interface: The radio interface determines not only the fundamental capacity of a mobile
radio network, but also it deals with such issues as interference, multipath distortion, and
handing off calls from one base station to another as users move around. Consequently, as might
be expected, the choice of radio interface has a dramatic effect on the complexity of the system
and its cost. Also, global travelers will need more than one phone with which to communicate, at
least until trim ode phones reach the market.
Air Interface: The Air Interface Processing System technique can dynamically respond to
changing RF conditions fast enough to minimize multipath fading and in turn increase both
download speeds and connectivity. The five 3G air interface technologies are as follows:
 Wideband CDMA (WCDMA)
 Code Division Multiple Access 2000 (cdma2000)
 Time Division Synchronous Code Division Multiple Access (TD-SCDMA)
 Universal Wireless Communications-136 (UWC-136)
 Digital Enhanced Cordless Telephone (DECT)
3.4 Optimization of 2G and 3G:
When analyzing a 2G network, engineers tend to focus on voice call related issues, such as call
quality, call failures and RF conditions. Engineers emphasize the importance of enhancing voice
call performance mainly by optimizing coverage or attempting to identify the root cause of voice
call failures due to adjacency definition, power control or handover parameter. With the
deployment of 3G networks, engineers must also take notice of network performance data
including maintaining balance between throughput, capacity and radio quality, and also IRAT
(Inter Radio Access Technology Handover), in order to ensure a seamless transition between 2G
and 3G networks.
3.5 The Platforms of 2G and 3G:
The key platform of 2G components are as follows:
 Comprehensive reference design on handset
 Industry-proven GSM software engine

50
 User-friendly development tools such as man-machine interface(MMI toolkit for rapid user
interface development
 Universal Wireless Communications-136 (UWC-136)
 Digital Enhanced Cordless Telephone (DECT)
Figure 3.2: A system diagram of the key components of the platform.
3G, just like other types of technology, also comes in various kinds and platforms. Depending on
the model, the speed, capacity and overall feature will also differ. Some of the top manufacturers
and investors have poured in a lot of effort and money just to create the right components that
will best suit consumers all over the world. Free scale features a wide range of platforms on the
cellular level, complete with components that will match the time-to-market and minimal cost
requirements of ODMs and OEMs. There is opening operating system support which also includes
S60, Microsoft Windows Mobile, Symbian and Linux. The world-class security in software and
hardware for secure transactions is also featured. Free scale also has low power style that
incorporates sophisticated techniques like dynamic voltage scaling, low leakage process for
optimum usage time and clock gating. Some of the products available include the MXC300-30
and MXC275-30. The 300-30 is a lone core modem platform of 3G which is used mainly for EDGE,
GSM, GPRS, HSPA and UMTS/WCDMA. The MX275-30 is a 2.75 one-core modem platform that is
mainly used for EDGE Type 12, GSM and GPRS.
3.6 Uses and Features of 2G and 3G:
The 2G technology is used in more than two hundred countries in the world today. Today, the
mobile phone connections in different countries of the world are based on digital signals and 2G
technology. Let us now learn about the main benefits of 2g technologies today.
The first among the many 2G technology advantages is that the digital signals require very little
battery power. Therefore it means that the mobile batteries can last longer. Digital coding also

51
reduces the noise in the line, thus improving the clarity of the voice. Moreover; digital signals are
looked upon as environment friendly. 2G technologies is that the lower power emissions have
also helped in dealing with health concerns. Nobody wants any unforeseen health concerns
arising due to the use of any technology. The introducing of digital data services, such as SMS and
email is one of the many 2G technology advantages. Going all-digital with the 2G technology has
allowed the world to shrink and come closer. Moreover, it is not possible to have two or more
"cloned" handsets having the same phone number, under 2G technologies. This has helped in
reducing any chances of fraud to a minimum. Improved privacy is another added advantage of 2G
technology, which was not possible with the earlier technologies. The use of digital data service
with 2G technology has helped mobile network operators to provide the SMS or short message
services to any mobile network at any time over the cellular phones. The digital encryption
provides privacy and safety to the data and voice calls, which is among the many other benefits
of 2G technologies. SMS is also a cheap and easy way to communicate with anyone. To sum up,
we can see many advantages of 2G technology. But using the 2G technology requires powerful
digital signals to help the mobile phones function. But the digital signals could be weak if there is
no network coverage in any specific area.
3G was successfully launched and introduced to millions of consumers all over the globe. Some of
the concerns between users and consumers are the pricey fees of input given for the 3G service
agreements and service licenses. Expense of 3G phones are also currently on the rise, as more
and more people are becoming aware of the advantages in terms of speed and connectivity.
There is a big amount of debt at present sustained by various telecommunication companies,
making it a very huge challenge to create the important infrastructure for 3G technology. There
are also several differences in the terms of the license. There may also be lack of member state
support for financially challenged operators. There can be inadequate buy-in by 2G mobile users
for the new services of 3G wireless. The prices of 3G mobile services in various nations be very
high, which includes access to the internet. There is also inadequacy of users required for 3G can
voice and data services of a handset and mobile device.3G is the most recent wireless technology
available. This provides wireless access to information and data to consumers from all areas of
the world and at different times and dates. All the functions in a 3G phone, would normally do
with current mobile device. The speed, efficiency and connectivity will be better than before. 3G
technology offers faster connectivity, best quality and fast internet access. Because of easy and
fast accessibility, get to enjoy data transmission speed up to a maximum of 2 Mbps, if the
individual is using the cellular phone on stationary phone. This also gives bigger and faster data
transfer rates of increased networking and connectivity. On top of it all, get to enjoy noise
resistance. The technology has increased bit rate that allows service providers to give high speed
internet facilities, host of the multimedia applications to customers and heightened call volumes.
The prices of units will differ, depending on the features and service provider. When somebody is
in a moving vehicle, expect to have slower speeds than usual.
3.7 Knowing the Different 3G/2G Types:
2G system was the maximization of the system capacity measured the number of user per
spectrum per unit area. 3G, just like other types of technologies also come in various kinds. One
can take advantage of the many features and developments by simply knowing how one type
differs from the other.

52
The Different Technologies: The 2G technology includes iDen, CDMA and GSM; with speeds less
than 29 Kbps. Included features are the push-to-talk, voice, conference calls, caller ID and SMS.
Discussing Security: Compared to its 2G predecessors, 3G networks are lot more secure that
allows the UE to authenticate the network it is attaching to, allowing the user to be certain that
the network is the right one and not just a mere impersonator. 3G networks usually make use of
the KASUMI block crypto, compared to the old A5/1 stream cipher. Several major weaknesses in
the cipher have been discovered, however. There is also end to end security provided when
application frameworks like IMS are accessed.
3.8 Some Consequences of 3G:
3G is a very new technology; it is easy to expect that there are some drawbacks as well. More
and more developments are being conducted by various manufacturers worldwide; to better
cater to the needs of consumers. The use of 2G technology requires strong digital signals to help
mobile phones work. If there is no network coverage in any specific area, digital signals would be
weak.
Some Backfires: Some devices, particularly the iPhone 3G, has no instant messaging options or
MMS, then take out the advantage of sending and receiving photos via MMS. There is inadequate
or missing expandable memory too. A number of devices may appear in a couple of variants,
namely the 8 and 16 GB built-in memory. The non-detachable battery also is a disadvantage,
since one has to put two and two together to get the needed energy. There are also limited
service providers selections, so one do not get to pick anyone’s personal ISP. Instead it is taken
and sold via a certain MSP Mobile Service Provider. The price of some 3G tools also may be very
expensive for a number of individuals.
For Security: 3G provides a bigger degree of security compared to 2G predecessors. It allows the
UE to authenticate the network that it is connected to, the consumer can be certain that the
network is the right one and not impersonated. 3G networks apply the KASUMI block crypto,
aside from the older A5/1 stream cipher. Several serious weaknesses in the KASUMI cipher have
been pointed out, however. End to end security is provided aside from the 3G network
infrastructure security, when frameworks of applications like IMS are connected to, although this
is not usually a property of 3G.
Some Issues: 3G is successfully introduced to consumers all over the globe, with a number of
issues being argued by both users and providers. Expensive input fees for the licenses and
agreements can be given, as well as several differences in the licensing terms.

53
Chapter 4
Migration Path and Challenges from 2G to
3G
Technology continues to create innovative products which are smaller, lighter and faster. The
transition from 2G to 3G promises to be just as revolutionary, making features available to users
in lightning fast speeds. As is the case with every new technology that aims to replace an older
technology, 3G did not outright replace 2G. 2G networks were pretty established by then and
migrating to 3G meant purchasing a new equipment for the Telco’s and purchasing new phones
for the users. That is why a gradual roll-out was the step taken by just about everyone, with 2G
and 3G networks coexisting in certain areas. This provides better flexibility to serve all customers.
But in some areas where the population is not as large, the introduction of 3G network
technologies are not as cost effective. That’s why there are still some areas with only 2G network
technologies and not 3G.
4.1 The road to 3G:
Just as there has been a continued migration of voice from fixed line to cellular, it is expected
that data traffic too will migrate from fixed to mobile. The conversion from 1G analogue
networks like AMPS and TACS to 2G digital networks like GSM, TDMA and CDMA, has allowed
carriers to increase network capacity, provide value-added services like caller identification, short
messaging, call-waiting, and increased functionality.
The evolution of networks from 2G to 2.5G and then to 3G (or straight from 2G to 3G) will enable
users to send and receive data over a wireless platform. 2.5G solutions, such as GPRS (General
Packet Radio Service or EDGE (Enhanced Data rates for GSM Evolution) offer mobile data services
at rates between 56 Kbit/s and 144 Kbit/s, the speed of conventional modems and ISDN lines,
respectively. With 3G will come full broadband applications at transmission rates that will
eventually reach 2Mbit/s.
4.1.1 The 2G Network:
Initially, 2G networks were created mainly for slow transmission and voice data. Because of the
quick changes in the expectations of users, these no longer meet the requirements today in
terms of wireless connection. The movement and evolution from 2G to 3G technology can be
divided into several phases, namely GPRS, EDGE and pure 3G.

54
4.1.2 On GPRS:
The first big step in the move to 3G happened through the launching and launching of General
Packet Radio Service or GPRS. The cellular services, mixed with GPRS resulted to 2.5G. GPRS was
capable of giving data rates ranging from 56 Kbit/s up to a maximum of114 Kbit/s. This can be
used for services like WAP or Wireless Application Protocol access, MMS or Multimedia
Messaging Service, SMS or Short Message Service and internet communication services like
World Wide Web access and email. GPRS is a top-effort packet switched service, compared to
circuit switching, where there is a given QoS or Quality of Service is certified during the
connection for non-mobile users. It gives medium speed data transfer, via the use of idle Time
division multiple access or TDMA channels.
4.1.3 The EDGE:
The GPRS networks have changed significantly to EDGE networks, through the presentation of
8PSK encoding. Enhanced information rates for EDGE or GSM Evolution, IMT Single Carrier or
IMT-SC and Enhanced GPRS is a reverse-compatible digital mobile phone technology, allowing
improved data transmission rates, as an extension over the standard GSM. EDGE can be counted
as a 3G radio technology, involved in ITU's 3G description, but is usually frequently referred to as
2.75G. EDGE was launched on GSM networks, starting in 2003, by Cingular now at the start in the
United States.
Figure 4.1: Percentage of Migration paths from 2G to 3G
4.1.3.1 Standardization of EDGE:
3GPP standardized EsDGE as it belonged in the GSM group. It is considered as an upgrade that
gives a potential 3-fold boost in the capacity of GPRS and GSM networks. The specification gets
bigger data rates by altering to very sophisticated processes of coding, particularly 8PSK, inside
the GSM timeslots. EDGE can be applied in various packet switched applications, like the internet,
other multimedia and video.

55
4.1.4 3G improve from 2G:
3G broadband features a wider range of services, advance network capacity and increased
information transfer rates over the previous generations. Based upon higher network bandwidth
than the first 2G digital cellular phones, 3G capable devices are able to support simultaneous
transmission of voice and data. Furthermore, it enables high capacity data transmission that
would support video streaming and web browsing capabilities.
4.2 Evolution to 3G Wireless Technologies:
4.2.1 Initial Coverage
Initially, 3G wireless technology will be deployed as "islands" in business areas where more
capacity and advanced services are demanded. A complete evolution to 3G wireless technologies
mandated by the end of 2000 in Japan (mostly due to capacity requirements) and by the end of
2001 in Europe. In contrast there is no similar mandate in North America and it is more likely that
competition will drive the deployment of 3G wireless technology in that region.
4.2.2 2G to 3G: GSM Evolution
The standardization of GSM900 was completed by the European Telecommunications Standards
Institute (ETSI) in 1990 and included all necessary definitions for the GSM network operations.
Several teleservices and bearer services have been defined (including data transmission up to 9.6
kbps), but only some very basic supplementary services were offered. As a result, GSM standards
were enhanced in Phase 2 (1995) to incorporate a large variety of supplementary services that
were comparable to digital fixed network integrated services digital network (ISDN) standards.
Figure 4.2: GSM Evolution to 3G

56
GSM Phase 2+ releases have introduced important 3G features such as intelligent network (IN)
services with customized application for mobile enhanced logic (CAMEL), enhanced speech
compression/decompression (CODEC), enhanced full rate (EFR), and adaptive multi-rate (AMR),
high–data rate services and new transmission principles with high-speed circuit-switched data
(HSCSD), general packet radio service (GPRS), and enhanced data rates for GSM evolution (EDGE).
UMTS is a 3G GSM successor standard that is downward-compatible with GSM, using the GSM
Phase 2+ enhanced core network.
4.2.3 Interworking with 2G and 2G+ Wireless Networks:
Just as there has been a continued migration of voice from fixed line to cellular, it is expected
that data traffic too will migrate from fixed to mobile. In the following figure 4.3 compares the
migration path from 1G to 2G with that of the migration path from 2G to 3G.
Figure 4.3: Migration comparison from 1G to 3G
The conversion from 1G analogue networks like AMPS and TACS to 2G digital networks like GSM,
TDMA and CDMA, has allowed carriers to increase network capacity, provide value-added
services like caller identification, short messaging, call-waiting, and increased functionality. The
evolution of networks from 2G to 2.5G and then to 3G (or straight from 2G to 3G) will enable
users to send and receive data over a wireless platform. 2.5G solutions, such as GPRS (General
Packet Radio Service or EDGE (Enhanced Data rates for GSM Evolution) offer mobile data services
at rates between 56 Kbit/s and 144 Kbit/s. With 3G will come full broadband applications at
transmission rates that will eventually reach .sAmb2 it
4.2.4 Migration Requirements:
With the growing demand in mobile services and need to connect corporate networks for data
communications, an intermediate generation (2.5G) of technologies were developed: GPRS and
EDGE (both in the GSM family), and CDMA 2000One X-RTT. While migrating from 2G to 2.5G,
operators made decisions based on their future planning and business interests targeting third

57
generation (3G) networks. From 2G to 2.5G, GSM operators migrated to GPRS and EDGE systems
with some of the TDMA operators also migrating to GSM/GPRS systems.
EDGE enabled services in 36 countries and many more are in deployment phase .On the other
hand, upgrade to EDGE required changes in both hardware and software. The highlights of the
migration from 2G to 2.75G were packet switched data and improved data rates from 14.4Kbps
to 160Kbps (GPRS), and to 473.6Kbps (EDGE).
3G wireless technology introduces new Radio Access Network (RAN) consisting of Node B and
RNC network elements. The 3G Core Network consists of the same entities as GSM and GPRS, 3G
MSC/VLR, GMSC, HLR/AuC/EIR, 3G-SGSN, and GGSN. IP technology is used end-to-end for
multimedia applications. ATM (Asynchronous Transfer Mode) a network technology based on
transferring data in cells or packets of a fixed size. The cell used with ATM is relatively small
compared to units used with older technologies. The small, constant cell size allows ATM
equipment to transmit video, audio, and computer data over the same network, and assure that
no single type of data hogs the line. 3G wireless solutions allow for the possibility of having an
integrated network for circuit- packet-switched services by utilizing ATM technology. The BSC
may evolve into an RNC by using add-on cards or additional hardware that is co-located. The
carrier frequency (5 MHz) and the bands (2.5 to 5 GHz) are different for 3G wireless technology
compared to 2G/2G+ wireless technology. Evolution of BSC to RNC requires support for new
protocols such as PDCP, RRC, RANAP, RNSAP and NBAP. Therefore, BTS (Base transceiver station)
evolution into Node B may prove to be difficult and may represent significant capital expenditure
on the part of network operators.
MSC evolution depends on the selection of a fixed network to carry the requested services. If an
ATM network is chosen, then ATM protocols will have to be supported in 3G MSC along with
interworking between ATM and existing PSTN/ISDN networks.
Figure 4.4: 3G requirements for migration

58
The evolution of SGSN and GGSN to 3G nodes is relatively easier. Enhancements to GTP protocol
and support for new RANAP protocol are necessary to support 3G wireless systems. ATM
protocols need to be incorporated to transport the services. The HLR databases evolve into 3G -
HLR by adding 3G wireless user profiles. The VLR database must also be updated accordingly. The
EIR database needs to change to accommodate new equipment that will be deployed for 3G
wireless systems. Finally, global roaming requires compatibility to existing deployment and
graceful fallback to an available level when requested services are not available in the region .
4.3 Evolution of Mobile Technologies:
The migration path from 2G to 3G is referred to as 2.5G and involves an interim position for data
services that are more advanced for 2G but not as robust as the 3G data services. The migration
strategies are:
 Technology Overlay
 Spectrum Segmentation
The choice of either strategy depends on the technology being used, the spectrum availability,
capacity constraints, and marketing.
Looking back at the 1G system, there were three major systems: AMPS, TACS, and NMT )900.(
Migrating from 1G to 2G (analog to digital systems) TACS and NMT operators migrated to GSM
systems where as AMPS operators moved to TDMA or CDMA, both operating in 800 MHz and
1900MHz technology is General Packet Radio Service (GPRS).
Figure 4.5: Mevice oadvapdvprovedeerforvance
It is the trigger to 3G services Evolution from 2G to 3G, 2G networks were built mainly for voice
data and slow transmission. Due to rapid changes in user expectation, they do not meet today's

59
wireless needs. Cellular mobile telecommunications networks are being upgraded to use 3G
technologies from 1999 to 2010. Japan was the first country to introduce 3G nationally, and in
Japan the transition to 3G was largely completed in 2006. Korea then adopted 3G Networks soon
after and the transition was made as early as 2004.
Figure 4.6: GSM Evolution for Data Access
The network connection is always on, so the subscriber is online all the time. From the operator's
point of view, it is important that GPRS investments are re-used when going to UMTS. Also
capitalizing on GPRS business experience is very important. From GPRS, operators could change
the network directly to UMTS, or invest in an EDGE system.
4.4 The Migration Options:
In this section we will discuss the migration process involved in:
1. GSM to UMTS (3G),
2. GSM to WCDMA (3G),
3. IS-95A/B to CDMA2000 (3G).
Highlighting the critical points migrating, from 2G to 3G, we concentrate on three pillars: New
spectrum, Additional cell sites, and Data capabilities.
 New spectrum: Unlike some competing technologies, GSM/ GPRS/ EDGE/ WCDMA/
HSDPA allow an operator to efficiently use their entire available spectrum for voice and

Thesis_A Study on 3G Mobile Technology

Thesis_A Study on 3G Mobile Technology

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