Report : 3rd
Generation technology
HISTORICAL REVIEW
Marconi’s innovative perception
of electromagnetic waves and the air interface in 1897 was the first milestone
on the important road to shared use of the radio spectrum. But only after
almost a century later did mobile wireless communication start to take off.
Despite a series of disappointing false starts, Communication world in the late
1980’s was rapidly becoming more mobile for a much wider segment of
communication users than ever before. With the advent of wireless technology, a
transition from point-to-point communication toward person- to-person
communication (i.e.; independent of position) has begun. Testimony to this is
the rapidly increasing penetration of cellular phones all across the world.
In anticipation of the growing consumer demands, the next
generation of wireless systems endeavors to provide person-to-person
communication of the circuit and packet multimedia data.
The first generation cellular networks, which were based on
analog technology with FM modulation, have been successfully deployed since the
early and mid1980’s. A typical example of a first generation cellular telephone
system (1G) is the Advanced Mobile Phone Services (AMPS). Second generation
(2G) wireless systems employ digital modulation and advanced call-processing
capabilities. In view of the processing complexity required for these digital
systems, two offered advantages are the possibility of using spectrally
efficient radio transmission schemes such as Time Division Multiple Access
(TDMA) or Code Division Multiple Access (CDMA), in comparison to the analog
Frequency Division Multiple Access (FDMA) schemes previously employed and the
provision for implementation of a wide variety of integrated speech and data
services such as paging and low data rate network access. Examples of 2G
wireless systems include the Global System for Mobile
communication (GSM), TDMA IS-54/IS-136 and Personal Digital Cellular (PDC).
Third Generation (3G) wireless systems will evolve from mature 2G networks with
the aim of providing universal access and global roaming. More important these
systems are expected to support multi-dimensional (multi-information media,
multi-transmission media, and multi-layered networks) high-speed wireless
communication- an important milestone toward achieving the grand vision of
ubiquitous personal communications. Introduction of wide band packet-data
services for wireless Internet up to 2Mbps will be the main attribute of 3G
system.
BACKGROUND
Third generation (3G) is the
generic term used for the next generation of mobile communications systems.
These have been created to support the effective delivery of a range of
multimedia services. In addition, they provide more efficient systems for the
over-the-air transmission of existing services, such as voice, text and data
that are available today.
According to the GSA, in December 2005 there
were 100 3G networks in operation in 40 countries in the world. In Asia , Europe , and the USA ,
telecommunication companies use WCDMA technology with the support of around 100
terminal designs to operate 3G mobile networks. In 2001, NTT DoCoMo-one of the
giant telecommunication companies in Japan -was the first
telecommunication company to launch a commercial WCDMA network. The
introduction of 3G services within Europe
began in early 2003. The official 3G mobile network is the systems and services
based on the International Telecommunication Union (ITU) family of standards
under the International Mobile Telecommunications program, "IMT-2000". A boost was given to 3G
mobile networks in Europe when the European
Union council suggested that the 3G operators should cover 80% of the European
national populations by the end of 2005. In Africa ,
Vodafone Egypt
(also known as CLICK GSM) will provide the service in Egypt in the
middle of 2007. Early 2007, Vodacom Tanzania switched on its 3G HSPDA
in Dar ea salaam. With the installation of a 3G HSDPA network, Tanzania is
only the second country in Africa with such
technology, the first being South
Africa .
1.1 WHAT IS 3G?
The third generations of mobile
cellular systems are intended to unify the diverse systems we see today into a
seamless radio infrastructure capable of offering a wide range of services in
different radio environments, with the quality we have come to expect from wire
line communication networks. Since the mid-80’s, studies on 3G systems have
been carried out within the International Telecommunication Union (ITU), where
it was called Future Public Land Mobile Telecommunication Systems (FPLMTS),
lately renamed International Mobile Telecommunications -2000 (IMT-2000). In Europe research and development on 3G technology, is
commonly referred to as the Universal Mobile Telecommunication System (UMTS)
and Mobile Broadband System (MBS), have been conducted under the European
Community Research into Advanced Communications in Europe (RACE) and Advanced
Communication Technologies and Services (ACTS) programs. With support from
activities in Europe, the United States, Japan and developing countries, World
Administrative Radio Conference (WARC) of ITU identified global bands
1885-2025Mhz and 2110-2200Mhz for IMT-2000 including 1980-2010Mhz and
2170-2200Mhz for the mobile satellite component. Key elements in the definition
of 3G systems are the radio access system and Radio Transmission Technology
(RTT). As a part of the standardization activities, a formal request by the
ITU-Radio communication standardization sector (ITU-R) for submission of
candidate RTTs for IMT-2000 has been distributed by the ITU. In response to
this 10 proposals were submitted. Most of the proposals use CDMA or WCDMA as
their multiple access technique. So in this seminar we are presenting the
common features of WCDMA based 3G standards.
1.2 3G EVOLUTION STAGES
Electromagnetic waves were first
discovered as a communications medium at the end of the 19th century. The first
systems offering mobile telephone service (car phone) were introduced in the
late 1940s in the United
States and in the early 1950s in Europe . Those early single cell systems were severely
constrained by restricted mobility, low capacity, limited service, and poor
speech quality. The equipment was heavy, bulky, expensive, and susceptible to
interference. Because of those limitations, less than one million subscribers
were registered worldwide by the early 1980s.
1.2.1 First
generation (1g): Analog cellular
The introduction of cellular
systems in the late 1970s and early 1980s represented a quantum leap in mobile
communication (especially in capacity and mobility). Semiconductor technology
and microprocessors made smaller, lighter weight and more sophisticated mobile
systems a practical reality for many more users. These 1G cellular systems
still transmit only analog voice information. The most prominent 1G system is
Advanced Mobile Phone System (AMPS), Nordic Mobile Telephone (NMT), and Total
Access Communication System (TACS). With the 1G introduction, the mobile market
showed annual growth rates of 30 to 50 percent, rising to nearly 20 million
subscribers by 1990.
1.2.2 Second
generation (2g): multiple digital systems
The development of 2G cellular
systems was driven by the need to improve transmission quality, system
capacity, and coverage. Further advances in semiconductor technology and
microwave devices brought digital transmission to mobile communications. Speech
transmission still dominates the airways, but the demands for fax, short
message, and data transmissions are growing rapidly. Supplementary services
such as fraud prevention and encrypting of user data have become standard
features that are comparable to those in fixed networks. 2G cellular systems
include GSM, Digital AMPS (D-AMPS), code division multiple access (CDMA), and
Personal Digital Communication (PDC). Today, multiple 1G and 2G standards are
used in worldwide mobile communications. Different standards serve different
applications with different levels of mobility, capability, and service area
(paging systems, cordless telephone, wireless local loop, private mobile radio,
cellular systems, and mobile satellite systems). Many standards are used only
in one country or region, and most are incompatible. GSM is the most successful
family of cellular standards (GSM900, GSM–railway [GSM–R], GSM1800, GSM1900,
and GSM400), supporting some 250 million of the world’s 450 million cellular
subscribers with international roaming in approximately 140 countries and 400
networks.
1.2.3 2g to 3g:
gsm evolution
Phase 1 of 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 tele-services 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. In 1996, ETSI decided to further enhance GSM in annual Phase
2+ releases that incorporate 3G capabilities.
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.
1.3 OBJECTIVES
Some major objectives envisioned
for IMT-2000 and their key differences from the current 2G mobile systems can
be briefly summarized as follows:
Use of a common frequency band.
Use of a small pocket terminal with worldwide roaming.
 |
Maximizing the commonality and optimization of radio interfaces for multiple operating environments, such as vehicular, pedestrian, office and Fixed Wireless Access (FWA) system. Significantly high transmission speed capability encompassing circuit and packet switched data with multimedia support. Support for both symmetric and asymmetric data transfer in all operating environments. Compatibility with wireless services, which currently exist. Spectrum efficiency, quality and overall cost improvement as a result of utilization of advanced technologies such as DSP.
Figure 1: Evolution
path of Wireless Communication Systems
1.4 EVOLUTION TO
3G
The primary focus of third generation architectures will be
to attempt to seamlessly evolve second generation systems to provide high speed
data services to support multimedia
applications such as web browsing. The key word is "evolve" - as the
challenge to wireless equipment manufacturers is to provide existing customers,
namely, service providers, with a migration path that simultaneously satisfies
the requirements set forth by the International Telecommunications Union (ITU)
for 3G wireless services while preserving customer investment in existing
wireless infrastructure. The core of today’s second generation networks provide
the foundation on which third generation services –3G-are built. Next generation
services will be delivered by a combination of existing and evolving digital
equipments. The move to 3G is all about high-speed mobile data and IP traffic.
That is why today’s wireless networks will require grater band width and
network capacity to support 3rd generation services.
table
1 : Comparing services/applications provision under 2G , 2.5G and 3G
1.5 3G STANDARDS
Third generation cellular
telephony is on its way - not, unfortunately, as a single worldwide system, but
as three incompatible ones. The main difference the three lies in their choice
of radio interface technology. This fact is crucial for several reasons, since
the f\radio interface determines not only the fundamental capacity of a mobile
radio network, but also how it deals with such issues as interference,
distortion, handing off calls from one base station to another as users move
around etc. In one way or the other, all three approaches provide for adaptive
bandwidth on demand. Two of the systems use wideband code division multiple access
(WCDMA) for the radio interface. The other uses a time division multiple access
(TDMA) radio interface technique.
1.6 TECHNOLOGY
INVOLVED IN 3G
1.6.1 WCDMA
One of the most promising
approaches to the new third generation is to combine a wide band CDMA (W-CDMA)
AIR INTERFACE with the fixed network of the GSM. With WCDMA a users ‘information
bits are spread over an artificially broadened bandwidth. The job is done by
multiplying them with pseudorandom bit
stream several times as fast. The bits in the pseudorandom bit stream are
referred to as chips, so the stream is known as chipping or spreading code. It
increases the bit rate of the signal (and the
amount of band width it occupies) by a ratio known as spreading factor,
namely, the ratio of the chip rate to
the original information rate. The key device in any CDMA system is its
correlation receivers, which stores exact copies of all the system’s chipping
codes. These codes are used by the receiver to multiply a received data stream,
selecting the chipping code as was used in the transmitter. The devices also
perform whatever mathematical functions required to restore the original user
data. The result is that at the receiver output, the amplitude of the de-spread
signal is increased by the spreading factor relative to the interfering
signals. In the process, those interfering signals are diminished and add to
the background noise level. This effect is called process gain. CDMA the
conversations occupy the same frequency band at the same time. But each interaction is multiplied by a
different chipping code, and when the signals are de-spread, the only one that
comes through intelligibly is the one whose code was used by the de-spreader.
The others simply add to the background noise level, which ultimately limit the
number of users that can share a channel. For the system to work two factors
are key. First only soft handovers may be employed, since with them mobile
terminals can maintain simultaneous connections to different base stations as
they move among them. Second transmitted power should be strictly controlled so
that signals from all mobile terminals arrive at the base station with about
the same strength, despite their differing distances from the base
station. Strict power control is
maintained with real time power control channels. The control channels operate
at power command rate between 800Hz and 1.5 kHz. That is base station equipment
measures the power received from each mobile unit as much as 1500 times a
second and issues command to the mobile at that rate to raise or lower their
output power. Many users can be accommodated. The maximum WCDMA chip rate is
3.84Mcps (mega chips per second) and yields a modulated carrier of about 5 MHz
wide. System operators can deploy multiple carriers, each of which occupies 5
MHz. More over in a WCDMA system, multiple end users can share each 5 MHz channel.
In addition to the above mentioned features a WCDMA system can support both
fixed and variable data rate users in
an adaptive manner.
Only key features are cited below.
• Radio channels are 5MHz wide.
• Supports two basic modes of duplex,
frequency division and time division. Current systems use frequency division,
one frequency for uplink and one for downlink. For time division, FOMA uses
sixteen slots per radio frame, where as UMTS uses 15 slots per radio frame.
• Employs coherent detection on uplink
and downlink based on the use of pilot symbols.
• Supports inter-cell asynchronous
operation.
• Variable mission on a 10 ms frame
basis.
• Multicode transmission.
• Adaptive power control based on SIR
(Signal-to-Interference Ratio).
• Multi-user detection and smart
antennas can be used to increase capacity and coverage.
• Multiple types of handoff between
different cells including soft handoff, softer handoff and hard handoff.
1.7 TRANSITION
FROM GSM TO 3G
The WCDMA physical layer
includes variable bit rate transport channels required for bandwidth on demand
user applications. These can multiplex several services onto a single
connection between fixed infrastructure and a mobile terminal. Some of the
physical channels do not carry transport signals, they do not carry user
information of any kind. They serve the physical layer itself, and include such
resources as some pilot channels (that assist in modulation recovery), a
synchronization channel (that lets mobile terminals synchronize to the network,
and an acquisition channel (that establishes the initial connections to the
mobile terminals). WCDMA resembles all CDMA systems currently deployed in that
it applies the spreading function in two phases. An initial channelization code
spreading is followed by a scrambling code spreading. The initial
channelization code spreading alone determines the occupied bandwidth of the
radio signal. As for the scrambling code, it is used to distinguish different
mobile terminals at the base station’s receiver and to distinguish multiple
cell sites in the mobile terminal’s receiver. The second-generation IS-95 CDMA
systems uses a single pseudo noise code common to all base stations, but
applied by each base station with different time offsets. WCDMA elaborates on
this scheme to allow for multiple connections to a single mobile terminal as
well as variable spreading factors at the channelization spreading stage. Low
user data rates get lots of coding gain with high spreading ratios while high
user data rates get less coding gain because of their lower spreading ratios.
The spreading details differ in down link (base to mobile) and the up link
(mobile to base) directions.
1.8 3G DATA RATES
The International
Telecommunication Union (ITU) has laid down some indicative minimum
requirements for the data speeds that the INT – 2000 standards must support.
These requirements are defined according to the degree of mobility involved
when the 3G call is being made. As such the data rate that will be available
over 3G will depend upon the environment the call is being made in:
• High Mobility: 144 kbps for rural outdoor mobile use. This
data rate is available for environments in which the 3G user is travelling more
than 120 kmph in outdoor environments.
• Full Mobility: 384 kbps for pedestrian users traveling
less than 120 kmph in urban outdoor environments.
• Limited Mobility: At least 2mbps with low mobility (less
than 10 kmph) in stationary indoor and short range outdoor environments.
• Satellite Environment: 3G is supposed to provide a minimum
data rate of 9.6 kbps in this environment.
1.9 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:
1. Used worldwide
2. Used for all mobile applications
3. Support both packet-switched (PS) and circuit-switched
(CS) data transmission
4. Offer high data rates up to 2 Mbps (depending on mobility/velocity)
5. Offer high
spectrum efficiency
Fig 2: Multiple Standards for
Different Applications and Countries
IMT–2000 is a set of requirements defined by the
International Telecommunications Union (ITU). As previously mentioned, IMT stands
for International Mobile Telecommunications, and “2000” represents both the
scheduled year for initial trial systems and the frequency range of 2000 MHz
(WARC’92: 1885–2025 MHz and 2110–2200 MHz). All 3G standards have been
developed by regional standards developing organizations (SDOs). In total,
proposals for 17 different IMT–2000 standards were submitted by regional SDOs
to ITU in 1998—11 proposals for terrestrial systems and 6 for mobile satellite
systems (MSSs). Evaluation of the proposals was completed at the
end of 1998, and negotiations to build a consensus among
differing views were completed in mid 1999. All 17 proposals have been accepted
by ITU as IMT–2000 standards. The specification for the Radio Transmission
Technology (RTT) was released at the end of 1999. The most important IMT–2000 proposals are the UMTS (W-CDMA) as the
successor to. GSM, CDMA2000 as the interim standard ’95 (IS–95) successor, and
time division–synchronous CDMA (TD–SCDMA) (universal wireless communication–136
[UWC–136]/EDGE) as TDMA–based enhancements to D–AMPS/GSM—all of which are
leading previous standards toward the ultimate goal of IMT–2000.
1.10
NEED FOR 3G
A study of revenue opportunities for 3G by the UMTS Forum
(which includes forecast data produced by Telecompetition) assumes that by
2010, 3G will comprise 28 per cent of cellular subscriber's worldwide, yielding
revenue of $322 billion per year (based on assumptions regarded as
conservative). The UMTS Forum study forecasts that revenue from non-voice
services will compensate for the expected decline in average revenue per user
from voice services, which is expected to fall sharply by 2010. Work by Pyramid
Research reinforces the UMTS Forum’s predictions. Pyramid forecasts that by
2003, fewer than 10 per cent of mobile subscriptions will be for 3G service.
This figure is predicted to exceed 20 per cent by 2005, suggesting that 3G will
not take off until 2004 or 2005. At that time, mobile Internet-related revenues
will account for approximately one-third of total revenue. In some regions, 3G
will be slower to gain a foothold. In Brazil , for example, it is expected
that by 2005 only 3 per cent of mobile subscriptions
will
be 3G, partly due to fact that licenses were awarded later and partly because
demand is less mature. As Europe is concluding
the process of spectrum allocation for 3G technologies, operators are facing a
number of dilemmas relating to the high cost of licenses (in some countries)
and the large investment required for network deployment. Many analysts predict
financial difficulties for 3G licensees. Though the valuation methods for
spectrum auctions have been subject to considerable debate, metrics used by
investors and analysts to valuate operators in the marketplace have not
changed; the ROI (Return on Investment) continues to reign as the foremost
preoccupation. Perceptions of the potential for recouping investment vary
depending on whether demand-pull or technology-push is considered the primary
driver for 3G growth.
Many
past observations have been discredited, as lessons from the 2G experience are
coming to the forefront. Corporate strategy based solely on increasing the
subscriber base, for example, has proven to be a double-edged sword for
operators, since pushing subscriber levels past a 10-20% threshold37 has
actually led to increased subscriber acquisition costs. Some analysts believe
that long before 3G networks are completed, alternative solutions in the range
of 2.5G technologies will replace them; the ends may not necessarily justify the
means (or the costs necessary to achieve 3G). More neutral observations point
to waves or cycles of success, one being Forrester. Prediction that operating
profits will disappear in 2007 and take six years to return, leading to
business failures and massive industry consolidation.
Chart
1 : Mobile
1.11
FEATURE
The most significant feature offered by third generation
(3G) mobile technologies is the capacity to support greater numbers of voice
and data customers -especially in urban centers -as well as higher data rates
at lower incremental cost than 2G.
By
using the radio spectrum in bands identified, which is provided by the ITU for
Third Generation IMT-2000 mobile services, it subsequently licensed to
operators. 3G uses 5 MHz channel carrier width to deliver significantly higher
data rates and increased capacity compared with 2G networks.
The
5 MHz channel carrier provides optimum use of radio resources for operators who
have been granted large, contiguous blocks of spectrum. On the other hand, it
also helps to reduce the cost to 3G networks while being capable of providing
extremely high-speed data transmission to users.
It
also allows the transmission of 384kbps for mobile systems and 2Mbps for stationary
systems. 3G users are expected to have greater capacity and improved spectrum
efficiency, which will allow them to access global roaming between different 3G
networks.
i)
AUDIO
Audio or video over the Internet is
downloaded (transferred, stored and played) or streamed (played as it is being
send but not stored). The different compression algorithms such as MP3 can be
used. With 3G, MP3 files will be downloadable over the air directly to the
phone via a dedicated server. The large computational power available in the 3G
phones helps the decoding of MP3 formats.
ii)
VOICE OVER INTERNET PROTOCOL
Another audio application for 3G
is Voice over IP (VoIP) – the ability to route telephone calls over the
Internet to provide voice telephone service at local call rates to anywhere in
the world. With the higher data rates supported by 3G, VoIP will be available
on mobile phones.
iii)
STILL IMAGES
Still images such as
photographs, pictures, letters, postcards, greeting cards, presentations and
static web pages can be send and received over mobile networks just as they are
across an IP based network.
iv)
MOVING IMAGES
Sending moving images in a
mobile environment has several vertical market applications including
monitoring parking lots or building sites for intruders or thieves, sending
images of a patient from an ambulance to a hospital, mobile video conferencing
applications etc.
v)
VIRTUAL HOME ENVIRONMENT (VHE)
A Universal Mobile
Telecommunications Services (UMTS) service that is often mentioned in the
vendor’s brochures is so called Virtual Home Environment, a service that simply
lets customers have seamless access with a common look and feel to their
services from home, office or on the move in any city as if they were at home.
VHE is there fore aimed at roamers, a small subset of mobile phone users. VHE
could also allow some other useful services by placing their Universal Identity
Module into any terminal and those terminals could be other than mobile devices
(if smart cards are more widely supported than they are today).
vi)
ELECTRONIC AGENTS
Electronic agents are supposed
to play an important role for mobile working in the future – as agents are
dispatched to carry out searches and tasks on the Internet and report back to
their owners. This is an efficient way to get things done on the move.
Electronic agents are defined as “ mobile programs that go to places in the
network to carry out their owner’s instructions”. Agents are self-contained
programs that roam communication networks, delivering and receiving messages or
looking for information or services. Certainly, 3G terminals will give their
owners much more control over their lives than today’s mobile phones. They will
be e-assistance, e- secretaries, e-advisors, e-administrators etc. This kind of
control is what home automation applications anticipate.
vii)
DOWNLOADING SOFTWARE
In the 21st century, software
will increasingly be downloaded electronically from the Internet rather than
purchased as boxed products in stores. This is like file transfer applications
that involve downloading the software itself. We might, for example need WinZip
or adobe acrobat to read a file and can download that over the 3G network to a
3G terminal. Additionally Application Service Provision (ASP) market in which
software platforms and server software is being hosted by third parties and
accessed by client software mimics this thin client world in which the
bandwidth is high enough for applications and files to be retrieved from the
Internet on the fly whenever they are needed.
1.12 3G DRAWBACKS
The main draw back of 3G is its
high cost. Considering a typical example, to set up 3G trial network
infrastructure The Nippon Telephone and Telegraph had to invest 18$ billion in
1999. Also a 3G phone may cost 1000$+. The second disadvantage is shorter battery
life of 3G phones when compared to 2G mobile phones. This is because 3G phones
have a comparatively larger display screen and the increased power consumption
of modern high speed DSP processors used in 3G phones. The most important
disadvantage of 3G services is the lack of an internationally uniformed
standard. The third generation cellular telephony is on its way, not as a
single worldwide system but as three incompatible ones. This will make the
global roaming difficult. For global roaming we have to use multimode phones,
which can operate in different radio interface standards and this will result
in costlier handsets.
1.13 VISIONS OF
THE FUTURE
3G is capable of providing very
high data rate in different radio environments. It can provide dream multimedia
services. At present there is no hope of a wireless communication technology,
which can perform better than 3G. It is expected that the trends should last
into a Fourth Generation (4G) of even better spectrum efficiencies, higher
radio carrier frequencies, even higher user data rates, and a blizzard of new
non voice applications plus the terminals to support them. A wireless terminal
that is your gateway to the world of voice data, video and multimedia
communications sounds possible sooner. The year is 2005, your traveling in the
passenger seat of your work-colleague’s car with a laptop computer in front of
you, you sip a cup of coffee while you write a short report on the meeting you
attended that day. Suddenly, you hear the tone that tells you there’s an
incoming videoconference call. You click on the screen icon, the computer
screen changes and you see your assistant’s face. The two of you have a brief
conversation. Then she tells you about a new intranet site that could b useful
for your next customer meeting. So without interrupting the conversation, you
take a look at the website, and your assistant guides you to the most
interesting pages. A few minutes later, your sales department calls and sends
you the technical specifications and pricing information that you need for your
next meeting. At the same time you send your completed report to the eight
people who need copies. Meanwhile, a memo from one of your co- directors
arrives on your computer. It’s about an important item on your own company, broadcast
on that morning’s TV news report. A clip of the TV item is attached to the
e-mail, so you watch it. This is not science fiction, it a preview of everyday
communication services that will be a commercial reality within the next few
years. So called “third generation” wireless services (also referred to as “3G
services”) will significantly expand the range of options available to users
and allow communications, information and entertainment services to be
delivered via wireless terminals. The exciting thing is that the foundation for
these services has already been laid down – in a shape of today’s digital
mobile phone networks. All that is needed to support these advanced multimedia
services is to expand the information capacity, or “bandwidth” of the radio
communications technology.
1.14 4 G OR BEYOND
THIRD GENERATION:
3G evolution uses partly beyond
3G technologies to enhance the performance and to make a smooth migration path.
A 4G system will be able to provide a comprehensive IP solution where Voice,
data and streamed multimedia can be given to users on an “Anytime, Anywhere”
basis, and at higher data rates than previous generations. There is no formal
definition for what 4G is; however, there are certain objectives that are
projected for 4G. These objectives include: that 4G will be a fully IP-based
integrated system. This will be achieved after wired and wireless technologies
converge and will be capable of providing 100 Mbit/s and 1 Gbit/s speeds both
indoors and outdoors, with premium quality and high security. Fourth
generation: According to the 4G working groups, the infrastructure and the
terminals of 4G will have almost all the standards from 2G to 4G implemented.
Although legacy systems are in place to adopt existing users, the infrastructure
for 4G will be only packet based (all-IP). Since 4G is a collection of wireless
standards, the final form of a 4G device will constitute various standards.
This can be efficiently realized using SDR (Software-Defined Radio) technology,
which is categorized to the area of the radio convergence. Some proposals
suggest having an open platform where the new innovations and evolutions can
fit. It is generally believed that 4th generation wireless networks will
support a greater number of wireless devices that are directly addressable and
routable. By increasing the number of IP addresses, IPv6 removes the need for
Network Address Translation (NAT), a method of sharing a limited number of
addresses among a larger group of devices.
1.14.1
ADVANTAGES:
In a fourth-generation wireless system, cellular
providers have the opportunity to offer data access to a wide variety of
devices. The cellular network would become a data network on which cellular
phones could operate -as well as any other data device. Customer will have very
easy access to the internet from any where without computer.
1.
In the Information age, customer shall have very high reach in information
sharing.
2.
There will be tremendous opportunities for different value added services.
3.
Mobile will act
as our purse. No problem from money hazardous such as picks pocketing, theft
etc.
4.
The Video conferencing may enhance the voice communication.
5.
Movie watching will be on our finger tips.
6.
Mobile will
replace the activities of Laptop or computer.
7.
Business and decision making will be faster due to high data transfer rate.
8.
Digital music online or on demand can be enjoyed.
9.
Advertising business will be in boom situation after implementation of such
services.
1.14.2
DISADVANTAGES:
1.
Advance Terminals are needed for different services.
2.
It requires high bandwidth for Backhaul.
3.
Profit will be less with compare to other country video market.
4.
Supporting infrastructure for payment has not been developed like in
Supermarket electronic capabilities, Petrol pump automation and all other
purchase place etc.
5.
Young generation may copy the MTV or FTV culture.
2 3G SERVICE IN NEPAL
2.1 HISTORY OF TELECOM IN
NEPAL
Nepal Telecom or Nepal Telecommunications Corporation
(NT/NTC) is the leading and the largest telecommunication company of Nepal. It
is also known as Nepal Doorsanchar Company Limited (NDCL). A former government
monopoly, it was converted into a Public Limited Company on April 14, 2004 . Nepal Telecom was the
only provider of basic telephony services in Nepal until United Telecom Limited
started providing services in 2003.
The Central Office of Nepal Telecom is located at Bhadrakali,Kathmandu .
It has branches, exchanges and other offices in 184 locations within the
country.It is the sole provider of PSTN, ISDN and Leased-Line services in Nepal .
Following the entry of Spice Nepal
into Nepal ’s
telecommunications industry, it is no longer the only provider of GSM service.
With 4828 employees, it is one of the
largest corporations of Nepal .
It has a total of 190 telephone exchanges in various part of the country
serving 470,212 PSTN lines and more than a million GSM cellular phones as of
Jan 2008. NT served about 95.7% of the total telephone subscribers of Nepal , as of
early \Services
The Central Office of Nepal Telecom is located at Bhadrakali,
Basic Telephony
ISDN
GSM Cellular Telephony
Internet Leased Line
WebSMS
Payphone
CDMA Network as SkyPhone
Wireless
CDMA EV-DO
3G
Intelligent Network
VMS
GPRS Service
Multimedia Messaging, MMS
DDN
ADSL
2.2 3G LAUNCHING IN NEPAL
Nepal Telecom (NT), the
state-run communication supplier, has launched Third Generation (3G) mobile
services from Thursday, 17 may 2007. The service is being launched on the
occasion of International Telecom Day. NT officials claim that Nepal is going
to be the first country in the South Asia
region where 3G
mobile services will be launched. According to NT terms , the SIM card for 3G
service has cost 4,195 Nepali rupees (abut 64.5 U.S. dollars) and its charges
is similar to that of prepaid mobiles.
The 3G services is available to
area within the Ring Road in the capital city.
Now Nepalese will be able to
surf internet from their compatible Mobile
handsets at more than a broadband speed of 384kbps. The mobile industry in Nepal started
booming just a year ago and now with 3G available it's having bright future
ahead. With introduction of 3G by Nepal Telecom it's now possible for Nepalese
to make video calls. As compared to India , India being booming economy and
being at top for Mobile penetration has just
been able to launch 3G .
From official NTC (Nepal Telecom)
site
below are the tariffs
Note:
Rs 73= 1 USD
Applicable
Tariff for 3G Mobile Service:-
Total
Cost - Rs 4195.00
Talk
Time Rs.3500.00
(above rates are inclusive of applicable taxes)
(above rates are inclusive of applicable taxes)
Validity
- 18 months
Video
Call - Rs 10.00/ minute *
Data
Service/ Video Streaming - Rs 0.02/ KB *
Recharge
Procedure & Validity as Namaste Prepaid Mobile
Rates
for Voice, SMS, VMS, CRBT, MMS and other voice related services will be
applicable as Nepal Telecom prevailing Namaste Mobile tariff.* exclusive of
applicable taxes
CONCLUSION
A tremendous growth of mobile
subscribers is expected, with nearly 1.8 billion in the year 2010 with a
dominant base in Asia. GSM is the mobile radio standard with the highest
penetration worldwide. Mobile multimedia will increase after the year 2000 to
about 60% of the traffic in the year 2010. Therefore third generation systems
have to support a wide range of services from voice to low data rate up to high
data rate circuit switched and packet oriented services. In addition a high
grade of asymmetry for data application is expected. With this wireless break through,
unified IP network including wireless and wire line provides a generic
information transmission platform for value added personal Internet services
and multidimensional wireless communication services.
In this seminar we briefly surveyed the
evolution 3G wireless systems from 2G and 2.5G technologies. Similarities and
key differences between the various 3G proposals submitted to ITU-R are
reviewed. IN order to have a common standard for RTT, it is imperative to carry
out harmonization in an international level.
With the recent technological breakthroughs in digital
signal processing, RF and battery technologies as well as developments in
modern VLSI chip designs, the dream of ubiquitous communication between any
one, any where, at any time is becoming a reality. To cut it short, we can say
that the wireless information super highway is converging to 3G and during the
coming decade we will see how 3G will make the other wireless communication
methods obsolute.
No comments:
Post a Comment