CAPACITY CALCULATION AND RADIO NETWORK PLANNING OF 3G NETWORKS FOR URBAN AREA

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1.1 Motivation

Implementation
of third-generation (3G) cellular systems is meaning of implementation of WCDMA
which is one of the main technology of third-generation. WCDMA is based on
radio access technique. ETSI Alpha group proposed the WCDMA technology for the
fifth time and has finalized in the year of 1999. ITU has standardized the
technique under the name of “IMT-2000 direct spread” and it’s also known of
UTMS. Because of complexity and versatility of WCDMA, it’s always a big
challenge for the scientist and researcher to implement WCDMA. The reason WCDMA
is viewed as a complex system because of arithmetic multiplicity of
transmission and receiving of signals, multiplicity of computing each single
device result and the multiplicity of the entire system. The main theme of the
WCDMA system is, user can simultaneously transmit data in different rates and
the transmission varies over time. Using of CDMA air transmission system
instead of using TDMA system WCDMA transmits higher data rates in to the GSM
systems. UMTS uses the WCDMA systems which are based on CDMA. WCDMA is the
dominating 3G technology, providing higher capacity for voice and data and
higher data rates WCDMA dominates the current 3G technology because of its
higher capacity for voice and data, which means the overall higher data rate.
Need for higher transmission of data rates in mobile services in today’s modern
world requires a new technology which is able to perform higher data. WCDMA
enables better use of available spectrum and more cost-efficient network
solutions WCDMA offers the use of better available spectrum in the network
which is also cost effective. Switching from GSM to WCDMA is also cost
effective. Operators can still use the core network of GSM and 2G/2.5G
services.

Orthogonal Frequency Division
Multiplexing (OFDM), uses FDM modulation technique to broadcast the high amount
of digital data through the radio wave among the wireless networks. OFDM works by splitting the radio signal into multiple
smaller sub-signals that are then transmitted simultaneously at different
frequencies to the receiver the main theme of OFDM is concurrent broadcasting
of high amount of data using different frequencies by splitting the radio wave
into multiple smaller sub-signals to the receiver. OFDM cuts the size of
crosstalk in signal broadcasting. 802.11a WLAN, 802.16 and WiMAX technologies
use OFDM. It’s also used in the ETSI’s HiperLAN/2 standard. In addition,
Japan’s Mobile Multimedia Access Communications (MMAC) WLAN broadband mobile
technology uses OFDM. In FDM, multiple signals, or carriers, are sent concurrently
over different frequencies between two points. However, the feedback of FDM is:
radio waves can travel different ways from broadcaster to receiver (by bouncing
off buildings, mountains and even passing airplanes); so the receiving end
faces the problem to sort all the resulting data. Orthogonal FDM uses the
technique of splitting smaller sub-carriers of frequencies to deal with this
multi-path problem. This reduces multi-path distortion and reduces RF
interference which allows greater result Multi-path distortion and Radio
Frequency interferences are minimized through this way.

1.2 Evolution
of Cellular Communications

During the last few years
wireless communication system has been transferred from low data-rate system to
high data-rate system containing of voice, images and even to videos.
Traditional systems as like modems, cellular systems,802.11b local area network
which used to have data rates of only to few Kbps has been switched to high
data-rate with few Mb per second containing of multimedia with videos. Even
data rate of few Mbps is going towards the few GB per second in the recent
technologies as like DSL, cable modems, and
802.11n local area networks (LANs) and ultra-wideband personal area networks
(PANs) [1]. Wireless telecommunication started during the years of 80’s named
to The First generation Systems (1G) using Advanced Mobile Phone Service (AMPS) for
the cellular analogue voice. During the year of 90’s 1G standard has been
switched to Second Generation System (2G). Digital voice with low bit data
rates has been taken place to the analogue voice. An example of such a cellular system is IS-54. At the
same time, wireless local area networks started becoming in service starting at
1 Mbps for 802.11b standards and extending to 11 Mbps close to the year 000
Standard for 802.11b local area networks has been improved from 1 Mbps to 11
Mbps by the year of 2000. Reason to this higher data rate in local area network
was the shorter distance to cover than to cover a large distance in the cellular
network. To support the recent 3G standard with the data of multimedia and
videos data rates has been improved to 100 Mbps. On the other hand data rates
of the wireless LANs standard of 802.11a and 802.11g has been improved to 100
Mbps. Near future Fourth Generation System (4G) will not only transmit very
high data rates but also will provide Quality of Service (QoS) with the
technique of IP. Below figure 01 shows the evolution of wireless communication
systems as they have gone from 1G to 4G systems.

Figure 1.1: Evolution of communications
systems.

1.3 Cellular Communications Review

Wireless
transmission are increasing at an amazing speed, with affirmation of rapid
growth in the areas of mobile users and terminals, mobile and wireless access
networks, and mobile services and applications. It is the perfect time to
explore the new technology like 4G mobile communication, because:

Practicability,
History over the last few decades shows that standards of the wireless
communication have been changed in every decade. In the current decade we
are at the end stage of the 3G standardization phase and opening stage of
the deployment of 3G.

To employ the
subscriber demand of the 21^st century it’s not the luxury that
to have multimedia high data rates in the 3G system but necessity to have
3G goals. Many of the 3G problems have not solved in the 3G but to intend
to solve in the 4G system.

Band of base station	869 to 894 MHz
Band for Mobile Unit	824 to 849 MHz
Forward channels and reverse channels spacing	45 MHz
Channel bandwidth	30 KHz
Size of full-duplex voice channels	790
Size of full-duplex control channels	42
Mobile unit maximum power	3 watts
Cell size, radius	2 to 20 km
Modulation, voice channel	FM, 12-KHz peak deviation
Modulation, control channel	FSK, 8-KHz peak deviation
Data transmission rate	10 kbps
Error control coding	BCH (48, 36, 5) and (40,28, 5)

	GSM	IS-136	IS-95
Year introduced	1990	1991	1993
Access method	TDMA	TDMA	CDMA
Base station transmission band	935 to 960 MHz	869 to 894 MHz	869 to 894 MHz
Mobile station transmission band	890 to 915 MHz	824 to 894 MHz	824 to 849 MHz
Spacing between forward and reverse channels	45 MHz	45 MHz	45 MHz
Channel bandwidth	200 kHz	30 kHz	1250 kHz
Number of duplex channels	125	832	20
Mobile unit maximum power	20 W	3 W	0.2 W
Users per channel	8	3	35
Modulation	GMSK	?/4 DQPSK	QPSK
Carrier bit rate	270.8 kbps	48.6 kbps	9.6 kbps
Speech coder	RPE-LTP	VSELP	QCELP
Speech coding bit rate	13 kbps	8 kbps	8, 4, 2, 1 kbps
Frame size	4.6 ms	40 ms	20 ms
Error control coding	Convolution 1/2 rate	Convolution 1/2 rate	Convolution 1/2 rate forward, 1/3 rate reverse

System will assure the
same voice quality as PSTN

System will co-op with
the data rate of 144 kbps in terms of high speed moving vehicles in a big
density of locations.

System will co-op with
data rate of 394 kbps for object of slowly moving or sitting at the same
place in a small location.

System will co-op with
the data rate of 2.048 mbps in an indoor office type location.

System will co-op with
symmetrical and asymmetrical data transmission rates

System will co-op for
both packet switched and circuit switched data services

An adaptive interface
to the Internet to reflect efficiently the common asymmetry between
inbound and outbound traffic

System will be able to
co-op with different bands of telecommunication accessories.

System will be more
flexible to introduce new services and technologies.

Technology	1G	2G	2.5G	3G	4G
Design Began	1970	1980	1985	1990	2000
Implementation	1984	1991	1999	2002	2010
Services	Analog voice, synchronous data to 9.6 kbps	Digital voice, Short messages	Higher capacity, packetized data	Higher capacity, Broadband data up to 2Mbps	Higher capacity, completely IP oriented, multimedia data
Standards	AMPS, TACS, NMT, etc.	TDMA, CDMA, GSM, PDC	GPRS, EDGE, 1xRTT	WCDMA, cmda2000	OFDM, UWB
Data Bandwidth	1.9 kbps	14.4 kbps	384 kbps	2 Mbps	10 Mbps – 20 Mbps
Multiplexing	FDMA	TDMA, CDMA	TDMA, CDMA	CDMA	FDMA, TDMA, CDMA
Core Network	PSTN	PSTN	PSTN, Packet network	Packet Network	All-IP Networks

Location

Protocol

Description

CS domain

BICC

ISUP

MEGACO

TUP

Bearer independent call control
protocol

ISDN User part

Media Gateway Control Protocol

Telephone User Part

CS and PS domain

BSSAP+

MAP

Base station Subsystem application
part plus

Mobile application part

PS domain

GTP-C

UTRAN

NBAP

RANAP

RNSAP

Node B Application part

Radio access network application part

Radio network subsystem application
part

Uu non-access stratum

GMM

Call control

GPRS Mobility Management

Session Management

Uu Access Stratum

RRC

Radio resource Control

USIM

TABLE 2.1: List of signaling protocols
in UMTS, according to their task.

2.3.2
User Plane Control

It
manipulates the data of user interest and carries small number of signaling
messages. In example we take Adaptive Multi Rate (AMR) codec. The voice calls
are transmitted at 64Kbps by circuit switch. For air interface, it is too fast
because Signal to Noise (SNR) ratio is rather low, so low maximum data rate.
The code AMR compresses the information on the path between MSC and mobile work
in a data rate 10 Between 4.7kbps and 212kbps, this increases the number of
mobiles in the cell. The ARM codec is implemented in the core network and
mobile compressed information from using ATM and IP.

Location

Protocol

Description

Service

CS domain

Nb UP

Nb user plane protocol

PS domain

GTP-U

GPRS tunneling protocol user part

GPRS

UTRAN

Iu UP

Iub UP

Iur UP

Iu User plane protocol

Iub User plane protocol

Iur User plane protocol

Uu Non-access

AMR

Adaptive multi rate Codec

Voice

Stratum

RLP

SMS

Radio Link protocol

Short message service protocol

CS Data

SMS

Uu access

BMC

Broadcast multicast control

CBS

Stratum

PDCP

Packet data convergence protocol

GPRS

USAT

USIM application toolkit

Table 2.2 : List of user plane protocols
in UMTS according to the task.

Location

Protocol

Description

CS domain

PCM

Pulse code modulation

CS domain

ALCAP

Access link control application protocol

PS domain

UTRAN

ATM

MTP

Asynchronous transfer mode

Internet Protocol

Message transfer part

Uu access stratum

MAC

PHY

RLC

Medium access control

Air interface physical layer

Radio link control

Table 2.3: List of transport protocols
in UMTS according to the task.

2.4 The Advantages of 3G Technology

§ Perform all those functions that they
perform at present with their mobile devices but at much higher speed than
before.

§ Provides them with faster connectivity,
faster internet access, and music entertainment with improved quality.

§ Can avail the benefits of video calling.

§ Clarity is better and the facility can be
enjoyed as long as both of are using the 3G technology.

§ Access any site on the Internet by using
your phone as a modem for computer or laptop and mail the important documents.

§ Downloading games and songs is much faster
with this technology

§ Can be also used for favorite search
engines to find information on news headlines, get information about the
evening weather.

§ Provide with the data transmission speed
of up to 2Mbps when the users are using the phone on stationary mode.

§ Provides significantly faster data
transfer rates of connectivity and increased networking and most importantly
the resistance to noise.

§ Increased the bit rate thus enabling the
service providers to provide high speed internet facilities, increased call
volumes and host of the multimedia applications to their customers.

§ All these services can be provided to the
customers on the basis of the amount of data they transmit and not on the time
for which they use the service thus making the services cheaper.

§ Beneficiary to the service providers as
well as the intermediaries like the content providers and the media houses who
are looking for an additional platform market their products. Basically it holds
three way benefits to all the parties involved.

Improved
performance over 2G, including:

ü Will ease spectrum constraints on the 2G
networks and accommodate subscriber growth

ü Will improve data opportunities as
spectrum constraints are a major barrier to adoption and usage; Indian
consumers already own c2m 3G devices

ü 3G spectrum will allow incumbents to
differentiate services from new entrants and regional players

ü Improved capacity

ü Improved coverage, enabling migration from
a 2G deployment.

ü A high degree of service flexibility,
including:

ü Support of a wide range of services with
maximum bit rates above 2 Mbps and the possibility for multiple parallel
services on one connection;

ü A fast and efficient packet-access scheme.

A high degree of
operator flexibility, including:

ü Support of asynchronous inter-base-station
operation;

ü Efficient support of different deployment
scenarios, including hierarchical cell structure and hot-spot scenarios;

2.5 Guidelines for Services

§ The 3G (3rd generation) mobile
telecommunications is the generic name for the next generation of mobile
networks that will combine wireless mobile technology with high data rate
transmission capabilities. The 3G
networks will be capable of providing higher data rates and will also be
capable of supporting a variety of services such as high- resolution video and multimedia
services in addition to voice, fax and conventional data services.

§ 3G spectrum will be permitted in the 2.1
GHz band.

§ The 3G licenses would be granted through a
controlled, simultaneous ascending e-auction, by a specialized agency to ensure
transparency in the selection process.

§ Besides the initial, one time spectrum
charge, it has been decided that the successful service provider would pay
additional spectrum charge of 0.5 % of their total Adjusted Gross Revenue
(AGR), as the recurring annual spectrum charge. This additional revenue share
is proposed to be 1% of AGR after 3 years from the date of spectrum
assignment.

§ The roll out requirements, including rural
roll-out, as well as stiff penalties for non compliance of the same has been
stipulated.

§ Mergers will not be allowed during the
initial five years. No trading/
reselling of spectrum is allowed.

§ The CDMA spectrum in 800 MHz band for
EV-DO applications would be treated separately from 2.1 GHz spectrum. If the
CDMA based service provider(s) ask for the EV-DO carrier of 2 x 1.25 MHz, they
would have to pay an amount proportionate to the highest bid for spectrum in
2.1 GHz band.

2.6 Issues of 3G Technology

Although 3G was successfully introduced to users across the world,
some issues are debated by 3G providers and users:

§ Expensive input fees for the 3G service
licenses in some jurisdictions

§ Differences in licensing terms between
states

§ Level of debt incurred by some telecommunication
companies, which makes investment in 3G difficult

§ Lack of state support for financially
troubled operators

§ Cost of 3G phones

§ Lack of coverage in some areas

§ High prices for 3G in some countries

§ Demand for high speed services in a
hand-held device

§ Battery life of 3G phones

2.7 Where was 3G spectrum first introduced

Japan was the first country to introduce 3G on a large commercial scale.
In 2005, about 40 per cent of subscribers used only 3G networks. It is expected
that during 2006 the subscribers would move from 2G to 3G and upgrade to the
next 3.5 G level.

The success of 3G in Japan also shows that video telephony was the killer
application for 3G networks. Downloading music was the biggest draw in 3G
services.

There are about 60 3G networks across 25 countries.

For
infrastructure providers 3G will be a value-add during slowdown, as they would
get to put in a lot of new developments. Layout of next generation networks
that are 3G compatible will help in better manageability of services over the
networks. Even service providers believe that 3G would make the entire mobility
space much more accessible. The broadband connection, as they have not reached
the set target, will also benefit with 3G coming to Bangladesh.

3G will help
service providers manage their existing infrastructure better and remain
competitive in a mobile number portability (MNP) regime. It will also generate
a more addressable market to the GSM service providers. They can go back to
their existing customer base and provide them with enhanced data services

3G will not only
make its presence felt in cities and towns but also bring in better and faster
networks to rural Bangladesh.

In the years to
come 3G would make a lot of difference in making business models more
innovative. 3G and WiMax will help solve the problem of low broadband
penetration in Bangladesh to a great extent. It is high time the government
realizes the need and use of 3G. In a fast growing economy these technologies
have the power to change the development roadmap of the country.

2.8 Worldwide 3G Subscribers

Japan is at the vanguard of
3G technology development, network build and commercialization. NTT DoCoMo
launched the world’s first commercial 3G network in late 2001, and while
service providers in 115 other countries have since followed suit, Japan still
lays claim to the largest 3G subscriber base in the world. With almost 92
million UMTS users at the end of March 2009, Japan has 50% more 3G subscribers
than the United States, and three times as many as South Korea.

Figure 2.4 : Worldwide 3G subscribers.

Over the next five years all
this will change. While Japan’s progress to date has been impressive, 3G users
now account for 85% of the total wireless subscriber base, which means the
technology now only has a limited pool of late adopters to migrate. Combine
that with a sub-4% annual growth rate across all wireless subscribers, and the
market is close to saturation. This is not the case with any other country.
None even comes close to the current Japanese 3G take-up rate, thus they have
plenty more growth potential.

With a substantially larger
population, the US will overtake Japan for 3G subscribers in 2011. At that
point the US 3G market will still be growing strongly, but within three years
it too will lose first place as China inevitably overtakes it. At around the
same time, India will surpass Japan and take over the number three spot in the
ranking. On a regional basis, the number of Asian 3G subscribers at the end of
2013 will be two times greater than the number of Western European subscribers
and four times greater than the number 3G subscribers in North America.

UMTS
and Quality of Service

3.1
UMTS Architecture

Universal
Mobile Telecommunications System (UMTS) is characterized by the development in
terms of various services and bandwidth. The evolution of these networks is
based on the GSM/GPRS networks. UMTS networks support all types of applications
like data, voice and video. While IP is the driving technology, UMTS introduced
a new radio access technology based on radio access network without any major
change to the core network.

Figure 3.1: UMTS model architecture

The
public land mobile network has two major divisions:

§
UMTS Terrestrial
Radio Access Network (UTRAN)

It handles all radio related functionalities.

§
Core Network

It is responsible for maintaining subscriber data and
for switching voice and data connections.

UMTS
architecture physically contains two main domains:

§
User equipment
(UE)

It is the area where users acquire the services of
UMTS

§
Infrastructure
domain (PLMN)

This domain includes the physical nodes responsible
for termination of the interfaces to provide end-to-end service to the user.

Each characterizes a maximum level group of physical
segments

The detailed description of
the UMTS domain architecture is depicted below:

3.2
UMTS domain

UMTS
domain is classified mainly in two parts.

§ User Equipment Domain

§
Infrastructure
Domain

3.2.1
User Equipment Domain

This
domain contains various mobile terminals and electronic smart card that is
removable as well as portable. This domain is divided into two parts.

§ UMTS Subscriber Identity Module (USIM)

§
Mobile Equipment (ME)

§

3.2.1.1
UMTS Subscriber Identity Module (USIM)

It
is an electronic smart card that contains the information about the user to
identify in the network. To enable the user in the network the SIM should be
connected in the ME.

3.2.1.2
Mobile Equipment (ME)

It
is the Terminal equipment that the subscriber can access the network by using
this equipment. It is capable both for transmission and reception. It is a sort
of transceiver.

3.2.2
Infrastructure domain

This
domain is the principle part of the UMTS Architecture. It is classified into
two parts.

§ Access Network domain

§
Core Network
domain

3.2.3
Access Network domain: It is used to
connect all the nodes with core network. It is as like as gateway to connect
with core network for node-B.

3.2.3.1
Universal Terrestrial Radio Access Network (UTRAN)

The
radio access network of UMTS is called UTRAN/Universal Terrestrial Radio Access
Network, which is responsible for radio resource, data, signaling traffic,
exchange between UE and CN, it also handles with drawl and allocation of radio
bearers required for traffic support and control to some extent UE mobility and
network access technology is based on WCDMA.

UTRAN
is combination of two parts.

§ Radio Network Controller (RNC)

§
Node-B

3.2.3.1.1
Radio Network Controller (RNC)

Radio
Network Controller is control unit of UTRAN, it performs various tasks and
controls all radio resources within RNC, and it is same as BSC in GSM. Most of
protocols between RAN and UE are implemented in the RNC, it communicates over
Iu interface with a maximum of one fixed network nodes SGSN and MSC. Each RNC
is allocated to an SGSN and MSC; it also has an option of using Iur-interface
to communicate over core network CN with neighboring RNC’s.

RNC
is responsible for the following:

Call Admission Control

In contrast to GSM, CDMA in UMTS provides a large number
of possible channels at the radio interface, but not all of these can be used
at the same time; this is because of interference that results from increasing
the number of channels used. Therefore RNC for individual call must calculate
traffic load for each cell. On the basis of this information Call Admission
Control (CAC) decides whether the interference level after the channel request
is occupied, acceptable and, if necessary, rejects the call.

Radio Resource Management

The RNC manages the radio resources in all the cells
attached to it. Utilization level, priority control and interface calculation
are responsibilities of RNC.

Radio Bearer set up and Release

The radio bearer in UMTS is the radio data channel within
access stratum above the Link Control (RLC) sub layer. The RNC is setup. The
responsibility of RNC is setting up, maintaining and ultimately releasing radio
bearers as required.

CODE Allocation

In UMTS CDMA codes are managed in code tree. The RNC
allocates part of these codes to each mobile and during the course of a
connection the allocation can be changed.

Power Control

CDMA network works efficiently when the transmitting power
of all mobile users is controlled. The actual fast control process takes place
in Node B but the target control values are established in RNC. The RNC only
perform (counter loop) loose power control to minimize the cell interference
between the adjacent cell within the RNS and between nearby RNS.

Packet Scheduling

The same resource at the radio interface is shared by the
mobile users in the packet data transmission. The cyclical allocation of
transmission capacity to mobile station individually is the responsibility of
RNC.

Handover control and RNS
relocation

Based on
the signal strength of the Node B and UE, the RNC decides another suitable cell
connection where the signal strength is strong during the UE moves out of the
range of one RNC. A new RNC is chosen for the user this is called RNS
allocation.

Encryption

The data is encrypted in the RNC, which is arrived for
transmission from fixed network.

Protocol Conversion

RNC is responsible for protocol conversion between core
network and Node B.

ATM Switching

The communication link between RNC and Node Bs and between
CN and RNC is generally on ATM router. The RNC connects and switch ATM
connection to communicate between different nodes. Iu core network (Iucs
MSC/GSM, Iups SGSN/GPRS), Iur (other RNCs), Iub (Base station are different
interfaces).

O & M

The data
available are transmitted over interface defined to an OMC operations and
maintenance center.

3.2.3.1.2
Node B

Node
B corresponds to the Base Transceiver Station (BTS) in UMTS. Node B can manage
one or more cells connected to RNC over interface Iub. Node B includes CDMA
receiver which convert the radio interface signal into data stream and then
forward to RNC over Iub interface. The CDMA transmitter prepares incoming data
for transport over radio interface and routes it to power amplifier, and
because of the large distance between the RNC and the Node B time critical
tasks are not stored in RNC. The RNC knows the exact picture of the cell
current situation and makes a sensible decision on power control, handover and
call admission control. The mobile station and Node B continuously measures the
quality of connection and interference level and the result is transmitted to
RNC. Node B, in some cases handles the splitting and combining data streams of
different sectors.

§
Node B cell
Types and Cell Hierarchy

UMTS
supports different cell types.

§
Macro cells

These are large cells and coverage area with radius
less than 250m, it has low traffic and roaming for UEs in rural areas and
highways.

§
Micro cells

These types of cells have medium coverage area and
cover radius of less than 150m, it has medium traffic load and modest roaming
in city parks etc.

§
Pico cells

These are called hot spots and having lower coverage
area, the radius is less than 50m; it has high traffic and limited roaming on
malls, offices, e.t.c.

Different hierarchy levels use different frequency
bands (5 MHz).

Routing Area
(RA)

Group of cells, efficient localization of UEs
(paging…), RAs contains fewer cells than Pico cells. UMTS cells predicted to be
more crowded.

Node
-B functions

§
Uplink signal
measurement

This involves the measurement of signal strength or
quality reporting to RNC.

§
Soft handover

UE receives the signal from two different antenna
elements of Node B, and combines received signals using RAKE- receiver. It
contains multiple antenna elements.

§
Power control
(Inner loop)

The inner loop power-control functions are to reduce ‘near-far
terminal and interference’ sharing among UEs in cells.

3.2.4
Core Network domain

The
core network controls the connection when the user initiates or terminates the
call to access Packet Switched (PS) or Circuit Switched (CS) services. The core
network also provides interworking with external networks, it also manages
mobility of the user in a home and visited network, also responsible for
location updating, authentication, control charging and accounting. The core
network of the UMTS is the combination of GSM network subsystem (NSS) and
backbone of GPRS with a complete new radio network (UTRAN). The main difference
between UMTS & GSM is the radio interfaces and access technique. This domain
consists of three parts

§ Home Network Domain

§ Serving Network Domain

§
Transit Network
Domain

3.3
Circuit Switched (CS) elements of Core Network

The
core network consists of the following elements:

§
The
Mobile-Services Switching Center (MSC)

It connects the UTRN and other MSC?s, and also manages
the mobility and registration of the subscriber, allocates the physical
resources in combination with UTRN. Call routing, call roaming, call handover,
charging and accounting are also controlled by MSC.

§
The Gateway
MSC (GMSC)

The GMSC collects location information of the UE call
to the MSC serving the UE current instant. It also ensures the internet
functionality with other networks like PSTN and N-ISDN.

§
The Home
Location Register (HLR)

This is the database which is shared by CS and PS
domains; it contains static information like MSISDN, IMSI, and UMTS
subscription information. In the CS domain, dynamic information like current
VLR address is used to route incoming calls towards MSC. In the PS Domain the
address of the serving SGSN contains in HLR.

§
The Visitor
Location Register (VLR)

This is a database which stores the information of the
user equipment which is located in the Local Area (LA) covered by VLR, which
stores MSNR (Mobile subscriber roaming number), TMSI, LA and supplementary
services like IMSI, MSISDN, and HLR address. One or more MSC can be linked with
VLR and may be embedded within the same MSC equipment.

§
The Equipment
identity Register (EIR)

The EIR shared database by CS and PS which maintains a
list of mobile equipments to prevent calls from stolen or unauthorized mobile.

The
Authentication Center (AuC)

This protected database accessed by HLR contains USIM
secret keys of each subscriber.

3.4
Packet switched (PS) elements of Core Network

The
modified version of the GPRS network is UMTS PS domain. In the core network the
PS domain co-exist with a CS domain and sharing HLR, EIR and AuC database. Two
additional physical nodes are required to support PS domain services that are
serving GPRS support Node (SGSN) and the Gateway GPRS Node (GGSN)

§
Service GPRS
Support Node (SGSN)

The SGSN responsibility is to communicate between UMTS
user and PS domain within the serving area. It is also responsible for user
authentication, ciphering, Integrity, Charging and mobility management
procedure for UMTS users, SGSN also have embedded VLR functionality, data
transfer and routing.

§
Gateway GPRS
Support Node (SGSN)

The GGSN responsibility is logical interface to
external packet data network (PDN). The protocol used by PDN is named PDP. The
data packet from SGSN is converted to PDP format by GGSN and sent to external
network. Network address (IP) can also be allocated dynamically by GGSN.

GGSN
and SGSN in the core network are connected by IP based GPRS backbone which can
be intra PMLN. Roaming agreement is required in case of connecting with
different PLMN or if it connects the GGSN/SGSN of the same GPRS provider or
inter-PLMN or when connecting GGSN/SGSN to different PLMNs.

3.5
Circuit Switched (CS) and Packet Switched (PS) in the core network

The
core network of UMTS is based on Circuit Switched (CS) domain and Packet
Switched (PS) domain. CS domain provides real time constraints such as Video
telephony and voice while the PS domain provides services like web browsing, email,
MMS/SMS. The core circuits switch and packet switch services can be accessed
simultaneously. Before access the mobile equipment has to register with the
required domain, the phase called IMSI attach, for registration with the CS
domain and “GPRS attach” for registration with the PS domain. TMSI (Temporary
Mobile Subscriber Identity) is assigned for access to CS domain and PTMSI
(Packet TMSI) for packet services. The terminations to the domains are done by
“IMSI detach” and “GPRS detach” respectively. When the registration occurs, the
user equipment is tracked by its location management procedures. Location Area
(LA) in the CS domain and routing Area (RA) in the PS domain. After
registration, the CS & PS can be accessed in one of the following configurations.

3.6
UMTS network interfaces

§ lub: Responsible
for connection between RNC and Node-B

§ lur: This
interface is used to connect two RNCs.

§ Uu: UTRAN
and UE are connected through this interface.

§ Iu: This
inter face help to establish link between RNC and 3G core network.

§ Iu-CS: Circuit
switched domain connects with the RNC using this interface.

§
Iu-PS: Packet switched domain connects with the RNC through
this interface.

3.7
Quality of Service in 3G Network

The
second generation of Global System for Mobile Communications (GSM)/code
division multiple access (CDMA) is necessary for one QoS option , which is
speech transmission at its full rate coding in GSM. Thereafter a half-rate
service and thus introduced a new QoS option. However the effect of this on communication
was to save network capacity, so it can serve more users in congested hotspots
rather than providing a new grade of service to all level of users. The offer
of full or half-rate was never given to the user; subscribers with half-rate
capable mobile phones were put onto half-rate, without the subscriber knowing
that the Quality of speech was deliberately lowered by the network being used.
In the evolution of 2.5G networks e.g. General Packet Radio Service (GPRS), an
attempt was made to introduce mechanism whereby the subscriber can request a
different QoS (throughput, packet delay, e.t.c). From study, the QoS metrics
are established at the beginning of the data transfer session at the PDP
CONTEXT setup. For instance, a user using an interactive service, might opt for
a service with faster reaction time/lower round –trip delay, that might be
suitable for a smaller packet delay at PDP context setup time, and the network
decide if its allowed or denied.

Table 3.1
UMTS QoS requirement

3.8
Benefits of QoS

QoS
enables a network to deliver classes of service (CoS), which means different
classes of treatment are given to different group of services and or group of
users. QoS allocates network capacity according to the type of service while
CoS do the provisioning of the preferred allocation of required network
resources in a way as of DiffServ for IP-based services. CoS is used in QoS
policy associated with the user and also used by the network to provide QoS
treatments to different services. 3GPP end-to-end QoS parameters, which also
include the identification and definition of UMTS architecture, bearer
services, and recommendations for supporting QoS mechanisms, it establishes
four UMTS QoS traffics for mobile and wireless data.

3.9
UMTS QoS Basic Classes

The
following traffic classes are available in UMTS/3GPP

§ Conversational

§ Interactive

§ Streaming

§
Background

Table 3.2 : Qualitative QoS requirements
for different applications

3.9.1
Conversational Class

This
is the class that involves real-time communication e.g. audio, video calls.
Generally the requirements for speech are low delay, low jitter, and clarity
with no reverberation. Failure to meet the basic requirement can result in lack
of quality and unacceptable. Subjective evaluations have shown that the
end-to-end delay has to be less than 400 ms for video and audio conversation.
Video application is another application that will use conversational class for
UMTS transport.

3.9.2
Interactive class

This
class mostly occurs in the internet, it allows smooth interaction of humans and
machines with other devices. Asymmetric type is used and buffering is allowed,
there is no guarantee of bit rate because it uses the best effort service model
while the delay factor is also kept at the minimum, example of applications
using this class are web browsing, server access, and database retrieval, also
is the emerging M-commerce application e.g. wireless auction and online games.

3.9.3
Streaming Class

This
class consists of real-time applications that exchange information between
viewer and listener; all multimedia services are present in this class.
Asymmetric traffic type is used in it and guaranteed bit rate is provided, here
we use the requirement for low jitter and media synchronization such as
Multimedia streaming.

3.9.4
Background Class

This
class includes all applications that either receive data passively or actively
request it, but without any immediate need to handle the data. Email is the
suitable example for this class, the traffic type is asymmetric, buffering is
allowed and high variable delay exists, bit rate does not provide any guarantee
because it relates to the best effort service model.

3.10
UMTS QoS Parameters and Attributes

The
following QoS parameters are defined for UMTS that are essential to maintain of
multimedia services.

Guaranteed bit rate (Kbps)

§ Maximum bit rate (Kbps)

§ Maximum service data size (octets)

§ Transfer delay (ms)

§ Delivery order (yes/no)

§ Service data unit size error ratio

§ Service data unit size format information (bits)

§ Residual bit error ratio

§
Delivery of
erroneous service data units (yes/no)

Radio Network Planning (RNP) and
Capacity Calculation for a small area in 3G

Radio Network Planning

Overview:

The
objective of radio network planning activity is to estimate the number of sites
required providing coverage and capacity for the targeted service areas and
subscriber forecast. This section describes a methodology that is suitable for
dimensioning and planning of a 3G network based on utilization of the OFDM and
OFDMA PHY of IEEE 802.16.

4.1 Nominal Point Planning using Google
Earth:

Google
Earth displays satellite images of varying resolution of the earth’s surface,
allowing users to see things like cities and houses looking perpendicularly
down or at an oblique angle, with perspective (see also bird’s eye view). The
degree of resolution available is based somewhat on the points of interest and
popularity, but most land (except some islands) is covered in at least 15
meters of resolution. Melbourne, Victoria, Australia; Las Vegas, Nevada; and
Cambridge, Cambridge shire include examples of the highest resolution, at 15 cm
(6 inches). Google Earth allows users to search for addresses for some
countries, enter coordinates, or simply use the mouse pointer to browse a
location.

We use Google Earth to plan the radio
network for 3G network. The procedures of Radio Network are given below
geographically:

Step 1:

Figure 4.1 : Site selection for RNP

At
first, we have to select the region where the plan belongs to set up. For doing
this we have to open the Google Earth software in the computer and using the
search bar the desired place can be found.

Here
we select Sukrabad area for the planning.

Step 2:

Figure 4.2 : Area selection for RNP

Now
we have to select the coverage area using ruler. The parameters should be in
circle and the distance would be near about 400 to 500 meters by considering
the antenna size and capacity. Here we take 500 meters for calculation. The
yellow colored circle shows the area what we have selected. Our center point is
Daffodil International University, Sukrabad.

Step 3:

Figure 4.3: Point selection for BTS
placement

Considering
our circle area in step 2, now we have to place the BTS’s. For doing this we
take three (3) different points by considering the zero (0) degree on North
Pole. There are three BTS’s should be in the cell. The direction of the BTS’s
in the cell is on zero (0) degree, 120 degree and 240 degree. Here we mark the
direction of BTS’s by using Red colored place mark. It should be noted that
North Pole should be in zero degree and this is calculated in anti-clockwise
direction.

Step 4:

Figure 4.4 : Several points selection
for BTS (3G Network) placement

Following
step 3 we take another two cells for BTS placement. This way we can cover the
whole country for 3G network configuration. Here we have shown only three areas
of the planning. The center points of the BTS’s are the green colored place
mark and three BTS’s are placed on each center point.

Step 5:

Figure 4.5 : Polygon of the perspective
cluster

After
taking the cell range in different areas we have made polygon for divide the
areas into regions. There are too many cells need to take for planning, but we
take few cells under a polygon. Polygon is necessary to operate every cell
efficiently.

4.2 Nominal Point Planning using
MapInfo:

MapInfo
provides location intelligence solutions through combining software, data (both
spatial and non spatial) and consultancy with project management, systems
design and development, training and support. MapInfo produces a wide range of
software including Spatial Cartridges for databases (Spatial Ware), Routing
(Routing J Server), Geocoding (MapMaker), Site Analysis (Any Site), Risk
Analysis, Market Analysis, Demographic Analysis (TargetPro) and the Envinsa web
services suite along with the more traditional Geographic Information System
(GIS) software. MapInfo’s GIS software products include the desktop GIS
software, MapInfo Professional, MapXtreme 2005 and MapXtreme Java for web-based
and desktop client mapping, as well as developer tools such as MapBasic. The
latest version of MapInfo Professional is v11.0, which was released on 19 June
2011 and now comes as standard in SCP Software Copy Protection.

MapInfo
provides the Confirm Asset Management product globally to address full life
cycle Asset Management Software and services to the public and civil
engineering sectors. MapInfo provides specific Training, Consulting, Project
Management services for this area.

At
first MapInfo Software must be perfectly installed in the computer and then the
software must be run from program files.

4.2.1 Configuring the Nominal Point
using MapInfo:

Step 1:

Figure 4.6 : Taking the Longitude and
Latitude in .xls format

From
Google Earth we save the planned polygon in .kml format, then open it in excel.
From there we take the values of Longitude, Latitude, Azimuth, Beamwidth and
Cell ID in three different angles.

Step 2:

Figure 4.7 : Opening the MapInfo

When
MapInfo is opened it appears the quick start menu. We have to open it as a
Table. Now we have to open the .xls file here from the location where it is
located.

Figure 4.8 : Opening
the .xls file from the location

Step 3:

Figure 4.9 : Configuring the Excel
Information Bar

Then
on the window the Excel Information bar is opened. Here we have to mark “Use
Row Above Selected Range for Column Titles and then press the OK button.

Step 4:

Figure 4.10 : Setting up the appropriate
values for variables

After
completing the Excel Information Bar we have to configure the “Set Field
Properties”. Here we set the values in appropriate types. Here the Fields are
Site_Name, Sector_ID, Longitude, Latitude, Azimuth, Beamwidth, Cell_ID and the
Types are Character, Float, Integer. The Site_Name, Sector_ID, Cell_ID is in
Character, Longitude and Latitude is to be in Float, Azimuth,Beamwidth is in
Integer.

Figure 4.11 : .xls file
in MapInfo

Now
the Excel file is opened with MapInfo. Then we find a page named as the
configuration. We select three areas and they are Dhanmondi, Sukrabad and
Kalabagan. Every site is divided into three different angles. The Beam width of
the sector is 90.

Step 5:

Figure 4.12 : Using the celltools option
to draw the Sector Symbol

Cell
tools and CellMaker is the new MapInfo tool. Celltool is found from the option
“Run Map Basic Program” and then show the path where the tool is usually found
in the “Library Section”. Then we will get a window with a new option named as
“CellMaker” in the menu bar and the window is just like below:

Figure 4.13 : Using the
CellMaker option for drawing the Sector Symbol

Step 6:

Figure 4.14 : Opening
the .TAB file

Using
the “CellMaker” tool we have to configure “Sector Builder” menu. Before doing
this we have to select the .TAB file and set the option Get Sector Designator
From in Site_Name. We can also configure it as Cell_ID, Longitude and Latitude.
The window will be same as below:

Figure 4.15 :
Configuring the Sector Builder Bar

Step 7:

Figure 4.16 : Configuring the style of
the BTSs

In
“Sector Builder” menu the parameters should configure with predicted format. In
this menu the options are “Get latitude from” which should be in “Lat”, “Get
longitude from” which should be in “Long”, “Get sector orientation from” which
should be in “Azimuth” and “Get sector beamwidth from” which should be in
“Beamwidth”. The site radius should be 2500 feet. After continuing the form the
plan will be shown with details with the parameters. The sites map will be like
as the below:

Figure 4.17 : Style of
BTSs

Step 8:

Figure 4.18 : Configuring the Layer
Control and Label

By
using the “Layer Control” and “Label” we have to customize the MapInfo at our
requirements. The Layer Control gives the support to configure the output
either on Site_Name or Sector_ID or Long or Lat or Azimuth or Beamwidth or
Cell_ID. We can choose one option or we can choose different options according
our requirements. After labeling the window becomes as the below:

Figure 4.19 : Final
view of the BTS’s placement

4.3 Capacity Calculation for a small
area in 3G

4.3.1 User Distribution in a Cell

For
capacity calculation at first we have to find out number of mobile user in a
cell in between total cell of the network.

Total
number of people in our selected area = 201,529 (Dhanmondi)

Number
of mobile user is 1 in between 6 people.

So,
the total Mobile Phone user in this area = 201,529/6

This
area requires 15-18 cells for the whole coverage.

We
assume,

This area requires 16 cells for
the coverage.

Thus,
total mobile user in 16 cells is 33588.17

Now,
total mobile user in 1 cell = 33588.17/16

= 2099.26

So,
number of user in a cell is 2100 (approximately).

Capacity
planning in WCDMA networks is much more complicated than in GSM/EGPRS. Factors
that affect the coverage calculations are load, interference, traffic
behaviors, speed of subscribers etc.

The
total channel pool can be obtained by taking the number of channels per cell in
the equally loaded case and multiplying that by 1+i, which then gives the single isolated cell capacity.

4.3.2 Uplink Interference for Each Cell

WCDMA
is an interference system limited by the air interference. Hence, capacity
planning would need to calculate the interference and the cell capacity, i.e. the
amount of traffic that is supported by a base station. The amount of uplink
interference has a great impact on the cell capacity and radius. The
interference margin (?) indicates the total amount of interference (including
thermal noise power) in comparison to the thermal noise:

Where,

E_b/N₀=
Signal energy per bit or noise spectrum density=1.5

N=total
no. of users per cell= 2100

R=bit
rate=12.2 kbps (fixed for 3G)

W=chip
rate=3.84 Mcps

I=other
cell to own cell interference, which is approximately 0.6

V_j=activity
factor for user j = 2.63 (when 3 sectors per cell)

The
interference margin, ?_UL=1.5(12.2/3.84)*2100*(1+0.6)*2.63

= 42.15 db/km

Thus,
the cell capacity, N_UL={42.15/(1+0.6)}[1+(3.84/12.2)/1.5*(1/2.63)]

=
28.45

So,
the channel in one cell is 28

Total
channel in all cells is 448

4.4 Improving Capacity

To
improve the capacity, should be noticed following things:

4.4.1 Consideration of Voice Activity

Human
conversation is characterized bursts of activity (talking) followed by periods
of inactivity (silence of the user). If the transmitter is turn off during
these silent periods, the interference to other transmitters will decrease.
Since interference is a limiting factor on the capacity, this reduction will
result in an increase in the overall system capacity. Typically 38% of the time
that a user is connected is spent talking. If we denote the voice gain factor by
V_j= 1/ voice activity (i.e. 1/0.38 in this case).

The
interference margin ?_u= 1.5 (12.2/3.84)*2100*(1+0.6)(1/0.38)

Where
V_j = 1/0.38

Interference
margin for downlink calculated in the same way.

4.4.2 Consideration of Sectoring

§
Those cells in
which there is expected to be heavy usage, such as those containing a heavy
area for example, a number of directional antenna may be used.

§
Employing
directional antenna reduces the interference and hence increases the possible
capacity.

§
There may be 2,3
or even 6 directional antennas used in a cell.

§
The increase in
capacity is by a factor slightly smaller than the number of antenna used, a
3-sector antenna would increase the capacity.

Conclusions

An
efficient network planning process is a vital aspect of 3G network. Key
differences arise between 2G and 3G networks due to the different levels of
service offered. It is important to identify and analyses the relationships
between capacity and coverage in such networks.

In
this project we have tried to do the coverage and capacity planning for a small
area. For this purpose we first selected a small area, calculated the coverage
and number of Base stations in our selected area according to the simulation by
MapInfo software. After that we discussed about the capacity planning and
calculate capacity for all cells in our selected area. User’s distribution in a
cell and interfaces for uplink and downlink, with the base of total number of
people of that area is also calculated in capacity planning part. In this part
we also tried to improve the capacity by considering human voice activity and
sectoring.

Future Work

At
the end of the network planning for the future we have to notice some issues
that is the fluctuation of the frequency, coverage area users and capacity of
the network. The capacity which is used in this network right now that is not
enough if we want to increase more user in future that’s why we must keep more
capacity for future distribution of user. And frequency is more than 2200MHZ in
3G. Thus in future we will increase the frequency. Another important thing is
that in this network we just designed the radio network for a small urban area.
We can design a huge network for 3G in the same way. But the spectrum allocation
has to be high. We can also design this network for the rural area. In future
we can use the fiber optic medium for this network to establish Base station to
Base station connectivity.

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1.3.1 First-Generation Systems

First
Generation Systems (1G) means the system which used the network of analogue
traffic system. AT&T is the first company in North America to introduce
first generation system to the customers in during the year of early 1980’s.
AT&T named the system as Advanced Mobile Phone Service (AMPS). Gradually
AMPS technology has been introduced to the countries of South America,
Australia and China. 1G constructs the primary architecture of cellular
communications and clarifies lots of foundational obstacle, such as adoption of
cellular architecture, multiplexing frequency band, roaming across domain,
non-interrupted communication etc. First Generation System wasn’t able to
support lot of services to the customer; primary goal was to support voice
chat.

Table 1.1: AMPS Parameters.

1.3.2 Second-Generation Systems

People
started to adopt First Generation AMPS mobile communication in a rapid way.
High volume of users started to warn the slower analogue system. Developers
started to think a new system which will provide higher quality signals. It’s
the time to develop Second-generation systems, which will satisfy high volume
of customer’s needs. 2G systems have been promote to provide higher quality
signals, high data rates for support of digital communication, and bigger
capacity. 2G systems will use digital technology which will guarantee more accurate
signals where as analogue communication was the technology for the First
Generation system. Whereas, both of the
system use digital signaling to establish connection from radio towers to the
telephone subscriber. Second Generation system could be divided in to TDMA or
CDMA standard according to the multiplexing they use. The main 2G standards
are: GSM, iDEN, IS-136 (D-AMPS), PDC are the example of TDMA-based second
generation standards. CdmaOne which is also called IS-95 is CDMA-based. Second
and Half Generation system is in the middle of Second generation and Third
Generation system mobile technology. Designers have to name “2.5G” system
because they have introduced a packet-switch-domain with the exiting
circuit-switch-domain. This new introduction did not provide higher data rate
because of jamming of timeslots in the circuit-switch domain. The main aim to
name the new technology to attract the new subscriber but officially 2.5G
system never existed. 2.5G system used some to technology of Third generation
system as like packet switching and have used some of the technology that have
been already used in Second Generation architecture of GSM and CDMA
communication. Global Pocket Radio Service is a 2.5G introduction, introduced
by used by GSM designers. Technologies of
EDGE for GSM and CDMA2000 1xRTT for CDMA, referred to 3G technology
cause of the higher data rate of more than 144 kbps but not quite as 3G
technology because original 3G technology has a way more faster data rate.
CDMA2000 without multi-carrier is the example of 2.75G technology. 2.75G are
those systems which partly quality the 3G technology but not all of the 3G
requirements, EDGE system is one of the example of 2.75G technology. Starting
from the year of 1990 lots of 2G systems has been introduced in the market.
Below table 1.2 shows technical perspective of the different 2G systems.

Table 1.2: Second-Generation Cellular
Telephone Systems.

1.3.3 Third-Generation Systems

Once
various kinds of 2G systems has been marketed, new people started to show their
interest into the cellular communication. Demands of new subscriber for higher
data rate increased. It’s the time to implement new system which will provide
more data rates.

The
primary goal of the Third-generation (3G) mobile communication is to satisfy
more high-speed technology which will higher data rates along with multimedia,
data, and video in addition to voice. International telecommunication Union
defined their outlook of requirements of the 3G cellular communication in the
year of 2000(IMT-2000):

As
of lot can assume that 3G communication is the new version of the 2G system
Actually it’s not true and the uses of the frequency spectrum is not the same
between the 2G and 3G system. Japan was the first country who constructs the
whole system and open up new frequency between the operators to the large
amount of customers in the year of 2005. The first country which introduced 3G
on a large commercial scale was Japan. Forty percent out of the total customer
in Japan subscriber started to use 3G technology by the year of 2005. Operators
are expecting to complete the conversion between 2G system to 3G systems mostly
by the year of 2006 and from conversion of 3G to 3.5 with the transmission of
data 3 Mbps are on the way.

Figure
02 below shows the substitute way of design method that has been approve as
part of IMT-2000.

Figure 1.2: IMT-2000 Terrestrial Radio
Interfaces.

The
requirements wrap a set of radio interfaces for optimized performance in
various radio environments. The main factor of the introduction of five
substitutes was to approve easy expansion from existing first and second
generation systems. The five substitutes show the expansion from the 2G. Two of
the requirements grow out of the work at the European Telecommunications
Standards Institute (ETSI) to establish a UMTS (Universal mobile
telecommunications system) as Europe’s 3G cellular standards. One of these is
known as Wideband CDMA or WCDMA and another one is IMT-TC or TD-CDMA. Another
CDMA-based system, cdma2000, has a North American origin Cdma-2000 is also
developed according to the specification of CDMA is the North American version.
Because of individual chip and technology of multi-carrier on cdma-2000, W-CDMA
differs from cdma-2000. Two other interfaces are IMT-SC is mainly developed for
TDMA-only communication and IMT-FC can be used by both TDMA and FDMA
frequencies to provide some 3G services.

1.3.4 Fourth-Generation Systems

This
latest standard of telecommunication is focused to aggregate and replace the 3G
standard, maybe in recent years. Connect information anywhere, anytime, with a
seamless communication to a broad range of information and services, and
receiving a high structure of information, data, pictures, video, and so on,
are the keys of the 4G communication. The future 4G basis will consist of a set
of broad communication using Internet protocol as a common protocol so that
subscribers are in command because subscriber will be able to select every
application and environment.

According
to the progressive features of cellular system, 4G will have higher bandwidth,

Higher
data rate, and easier and quicker handoff and will focus on seamless
applicability across a multitude of mobile systems and networks. The main focus
is integrating the 4G capabilities with all of the existing mobile technologies
through advanced technologies. Application adaptability and being highly
dynamic are the main features of 4G services of concern to subscribers. These
features mean services can be delivered and be available to various subscribers
and assist the subscriber in moving traffic, air interfaces, radio environment,
and supreme perform of service. Linking to the cellular communication can be
transform into multiple forms and layers correctly and easily. The commanding
method of access to this pool of information will be the cellular telephone,
Personal Digital Assistant, and laptop to seamlessly access the voice
communication, high-speed information services, and multimedia broadcast
services. The 4G will support most systems from different networks, public to
private; company based broadband connection to private areas; and ad hoc
networks. The 4G systems will run with cooperation of with 2G and 3G systems,
as well as with broadband transmission systems. Furthermore, 4G systems will
provide Internet Protocol passed wireless communication. This entire aspect
shows the various range of systems that the 4G defines to satisfy, from
satellite broadband to high distance platform to cellular 3G and 3G systems to
wireless local loop and fixed wireless access to wireless local area network
and personal area network, all with Internet
Protocol as the adapting technique.

Table 1.3: Short history of cellular
communications evolution.

1.4
3G Mobile Networks

International
Telecommunication Union (ITU) planned in order to implement a frequency band of
2000MHz globally. The International Mobile Telephone IMT2000 supports technical
analysis for high-speed telephone solutions. The world of wireless
communication development arrives at GSM.IS – 136/PDC AND CDMA. The 3G
evolution for CDMA system brings CDMA2000. THE 3G evolution for GSM, IS-136 and
PDC system leads to Wideband CDMA (W- CDMA), also known as Universal Mobile
Telecommunication Service (UMTS). W-CDMA is based on the network fundamentals
of GSM with the same improvement also implemented in GSM and IS-136 through
EDGE.

Past
communication was mostly depending only on 2G but due to advancement in
technology, there was an introduction of latest technology such as Wireless
Internet Access (Wi-Fi and Video telephony which require universal standards at
higher user bit rates.

Different
Features of 3G Networks

2.1
Different Features of third Generation (3G) Technologies

Third
Generation (3G) technology is standard for mobile communication. Different
standards are required to cooperate for working together. The solution is
provided by standardization bodies and promoted to the third Generation
partnership program (3GPP).

The
3GPP consists of the following components

§
The access
Network

The access network depends on the radio interface of
Universal Terrestrial Radio Access (UTRA) which has two operation
modes, Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

§
The core
Networks

The core network developed for 3GPP is evolved from
the GSM core network with the addition of some new technology like Gateway
Mobile Location Center (GMLC).

3GPP adopted two new approaches in developing new
radio scheme which was based on Wide band CDMA (WCDMA), it provides FDD and TDD
mode of operations, and the realization of the network elements from 2G and
2.5G like Visitor Location Register (VLR), Authentication Unit (AuC), Equipment
register (ER), Home Location Register (HLR), Gateway GPRS Support Node (GGSN)
e.t.c, which resulted into a new mobile technology with upgraded software and
hardware and higher bandwidth usage.

2.2
CDMA2000

CDMA2000
network is able to provide data rates of 144kbps and the voice quality is twice
better than the CDMA one system. The system architecture that makes up the
CDMA2000 is the same as the CDMA one with the fundamental difference of the
introduction of the packet data services. The introduction of data service
meant that Base Transceiver Station (BTS) and Base Station Controller (BSC)
should be upgraded to handle this packet data services. The network of CDMA2000
consists of three major parts which are the Radio access network (RAN), Core
Network (CN) and Mobile Station (MS), the CN can then be further divided into
two parts, one part is that which interacts with the PSTN and the other is
connected to the internet.

Figure 2.1: CDMA2000 architecture.

2.3
3G W-CDMA (UMTS)

This
technology supports up to 14.0 Mbps data transfer rate, the mobile phone
supports 384Kbits/s which is more than 9.6kbps of a single GSM circuit switched
channel. UMTS has a frequency band of 1885-2025MHz and 2110-2200MHz for uplink
and downlink respectively; it uses a pair of 5MHz channel over W-CDMA.

2.3.1
Protocol and interfaces

There
exist a number of interfaces in UMTS network with its respective protocol
stack, the figure below shows a basic pattern of protocol stacks which vary
from one interface to another.

Figure 2.2: Model of protocol stacks in
UMTS.

The
application layer creates and interprets the UMTS signaling messages and also
manipulates data streams, while the transport layer is responsible for
transferring the data streams from one network component to another. We can
roughly say that in the OSI model the application layer are from 5-7 and
transport layer contains OSI layers 1-4. The three planes for protocol stack
are user plane which carry information from the user such as data packets or
voice, while signaling messages are carried by control plane. The transport
control plane carries internal signaling messages if the data transports using
ATM. In application layer the control plane contains signaling protocols use by
the network elements to communicate with each other. The user plane protocol
manipulates the date, i.e. compression and decompression.

2.3.1.1
Signaling Protocols

The
application layer protocol shows how they operate Radio Resource Controls (RRC)
(which lies between mobile equipment a serving radio network controller SRNC)
figure 2.3 shows the signaling procedure, The SRNC can be used to find mobile
capabilities. In the first step the RRC message is composed by SRNC known as UE
capability enquiry, which is sent to the mobile, the mobile replies with the
capability information that include different parameters that describes its
capabilities. (e. g. maximum data rate, number of data rate stream
simultaneously). It can handle a whether to support or not to support GSM.

The
SRNC replies with conformation in formation. When time expires before receiving
SRNC’s conformation, it retransmits its capability information.

Figure 2.3: Operation of the RRC
Protocol in the UE capability enquiry procedure

The
MAP mobile application part handles signaling communications across different
interfaces in the core network. If a call from the mobile to gateway MSC
arrives, the MAP message will be sent to the HLR by GMSC and will ask for
mobile current location. So it will be able to forward the call to correct MSC.
The radio access network application part (RANAP) and radio network subsystem
application part (RNSAP), Node B application part (NBAP) and radio network
subsystem application part (RNSAP) have similar role in the radio access
network on the Iub, Iu and Iur interfaces respectively.

The
air interface has two levels non access stratum (NAS) and access stratum (AS)
Protocol, which lays in the non access stratum exchange messages between the
core network and the mobile. The four of these are call control (CC) protocol
which runs in the circuit switch domain and the mobile, and manages setup and
tear down data transfer. The mobility management (MM) and the GPRS mobility
management (GMM) protocols handle bookkeeping messages which only effect the
internal operation in the system and not related to any data stream. The RCC
protocol lies in the access stratum and use for exchanging messages between the
radio access network and mobile.

2.3.1.2
Transport Protocols

In
the air interface access stratum, information is transported using unique
protocols to UMTS. The physical layer air interface is most important. The
physical layer is assisted by two layer protocols, the Medium Access Control
(MAC) protocol and Radio Link Control (RLC) protocol. The MAC controls the
physical layer e.g. at a particular time how much data is transmitted to and
from the mobile station. While RLC manages the data link between the radio
access network and the mobile by task. As retransmitting of data packets in
case of incorrect arrival, we can roughly say that the physical layer is
implemented in the Node B and in the mobile. While RLC and MAC are implemented
in the mobile and it’s serving RNC. The circuit switch domains transmit voice
calls using pulse code modulation PCM. This transport mechanism is used in
digital fixed line phone network. The analogue speech signal is digested with 8
bit resolution at a sample rate of 8 KHz to give 64 Kbps bit rate. The
resultant signal is converted into symbols, then mixed with a carrier and
multiplexed with other PCM signals, before transmission there is no processing
lie compression or error correction. In other parts of the network, the
protocols use for data transportation or Asynchronous Transfer Mode (ATM),
internet protocol IP and Message Transfer Part (MTP) of SS7 protocol stack.

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