this is a paper of 4G

1. IJASCSE, Vol 2, Issue 2, 2013
www.ijascse.in Page 39
Apr. 30
3 “G” SUCCESSOR
Dr. Avinash Sharma1
, Anurag Bhatnagar2
, Mayank Garg3
, Sonali Jain4
1
Principal & Professor,Advait Vedanta inst. Of Tech, Jaipur
2
M.Tech. Pursuing Rajasthan Technical University
Abstract - World is getting faster every day and everyone wants
to compete with it. In the era of internet 4G is the latest
innovation in India so we had done a survey on 4G technology.
Our paper focused on various transmission technologies along
with comparative study of 4G technology. And also this paper
shows problems with 4G. “4G” is short for Fourth (4th)
Generation Technology. It is basically the extension of 3G
technology with more bandwidth and services. The expectation
form the 4G technology is basically the high quality audio/video
streaming over end to end Internet Protocol. 4G Technology
offers high data rates that will generate new trends for the
market and prospects for established as well as for new
telecommunication businesses. 4G networks, when tied together
with mobile phones with in-built higher resolution digital
cameras and also High Definition capabilities will facilitate video
blogs. The technologies that fall in the 4G categories are UMTS,
OFDM, SDR, TD-SCDMA, MIMO and WiMAX to the some extent.
The word “MAGIC” also refers to 4G technology which stands
for Mobile multimedia, Any-where, Global mobility solutions
over, integrated wireless and Customized services.
Keywords -UMTS, OFDM, MIMO, WiMAX, 4G.
I.INTRODUCTION
What is 4G?
4G mobile technology is the name given to the next
generation of mobile devices such as cell phones. It is a
successor to the 3G and 2G families of standards. It became
available from at least one provider in several parts of the US
in 2009. The use of G, standing for generation, in mobile
technology covers the major advances of the past 20-30 years.
1G technology involved the first widely available mobile
phones. 2G technology, which began in the early 1990s,
switched to a digital format and introduced text messaging.
3G technology improved the efficiency of how data is carried,
making it possible to carry enhanced information services
such as websites in their original format. The latest iPhone is
the best known example of 3G technology.
4G mobile is not yet established as an agreed set of standards,
so its features are currently simply goals rather than
requirements. As well as drastically increasing data transfer
speeds, 4G mobile should use enhanced security measures.
Another goal is to reduce blips in transmission when a device
moves between areas covered by different networks. 4G
mobile networks should also use a network based on the IP
address system used for the internet. Within the United States,
there are two major systems using 4G mobile technology. One
is known as WiMax and is backed by Clear wire, a firm whose
majority owner is Sprint Nextel. It began testing services in
Baltimore in 2008 and was set to expand this into major new
markets in 2009. Sprint intended to have 80cities covered by
the end of 2010. The rival system, Long Term Evolution or
LTE, is backed mainly by Verizon. It was expected to be
ready for testing in 2010 but not available for widespread use
until 2014. LTE's backers hoped to overcome this
disadvantage by offering faster speeds and producing cheaper
equipment.
II.UNIVERSAL MOBILE TELECOMMUNICATION
SYSTEM (UMTS)
UMTS is one of the third-generation (3G) mobile
telecommunications technologies, which is also being
developed into a 4G technology. The first deployment of the
UMTS is the release99 (R99) architecture. It is specified by
3GPP and is part of the global ITU IMT-2000 standard. The

2. IJASCSE, Vol 2, Issue 2, 2013
www.ijascse.in Page 40
Apr. 30
most common form of UMTS uses W-CDMA (IMT Direct
Spread) as the underlying air interface but the system also
covers TD-CDMA and TD-SCDMA (both IMT CDMA
TDD). Being a complete network system, UMTS also covers
the radio access network (UMTS Terrestrial Radio Access
Network, or UTRAN) and the core network (Mobile
Application Part, or MAP), as well as authentication of users
via SIM cards (Subscriber Identity Module).
Features of UMTS –
UMTS, using 3GPP, supports maximum theoretical data
transfer rates of 45 Mbit/s.[3]
 The 3GPP Long Term Evolution project plans to
move UMTS to 4G speeds of 100 Mbit/s down and
50 Mbit/s up, using a next generation air interface
technology based upon Orthogonal frequency-
division multiplexing.
 The first national consumer UMTS networks
launched in 2002 with a heavy emphasis on telco-
provided mobile applications such as mobile TV and
video calling.
 The high data speeds of UMTS are now most often
utilised for Internet access: experience in Japan and
elsewhere has shown that user demand for video calls
is not high, and telco-provided audio/video content
has declined in popularity in favour of high-speed
access to the World Wide Web - either directly on a
handset or connected to a computer via Wi-Fi,
Bluetooth, Infrared or USB.
2. Migrating from GPRS to UMTS –
From GPRS network, the following network elements can be
reused:
 Home Location Register (HLR)
 Visitor Location Register (VLR)
 Equipment Identity Register (EIR)
 Mobile Switching Centre (MSC) (vendor dependent)
 Authentication Centre (AUC)
 Serving GPRS Support Node (SGSN) (vendor
dependent)
 Gateway GPRS Support Node (GGSN)
The UMTS network introduces new network elements that
function as specified by 3GPP:
 Node B (base transceiver station)
 Radio Network Controller (RNC)
 Media Gateway (MGW)
The functionality of MSC and SGSN changes when going to
UMTS. In a GSM system the MSC handles all the circuit
switched operations like connecting A- and B-subscriber
through the network. SGSN handles all the packet switched
operations and transfers all the data in the network. In UMTS
the Media gateway (MGW) take care of all data transfer in
both circuit and packet switched networks. MSC and SGSN
control MGW operations. The nodes are renamed to MSC-
server and GSN-server.
III.ORTHOGONAL FREQUENCY DIVISION
MULTIPLEXING (OFDM)
It has been selected as the basis for the high speed wireless
local area network (WLAN) standards by the IEEE 802.11
standardization group [1]. OFDM is also being pursued for
dedicated short-range communications (DSRC) for road side
to vehicle communications and as a potential candidate for
fourth-generation (4G) mobile wireless systems. OFDM
converts a frequency-selective channel into a parallel
collection of frequency flat sub channels. The sub carriers
have the minimum frequency separation required to maintain
orthogonally of their corresponding time domain waveforms,
yet the signal spectra corresponding to the different sub
carriers overlap in frequency. Hence, the available bandwidth
is used very efficiently. If knowledge of the channel is
available at the transmitter, then the OFDM transmitter can
adapt its signaling strategy to match the channel. Due to the
fact that OFDM uses a large collection of narrowly spaced sub
channels, these adaptive strategies can approach the ideal

3. IJASCSE, Vol 2, Issue 2, 2013
www.ijascse.in Page 41
Apr. 30
water pouring capacity of a frequency- selective channel. In
practice this is achieved by using adaptive bit loading
techniques, where different sized signal constellations are
transmitted on the sub carriers.
1. Use’s of OFDM –
 OFDM is used by many power line devices to extend
Ethernet connections to other rooms in a home
through its power wiring. Adaptive modulation is
particularly important with such a noisy channel as
electrical wiring.
 OFDM is also now being used in the
WiMedia/Ecma-368 standard for high-speed wireless
personal area networks in the 3.1–10.6 GHz ultra
wideband spectrum.
 Much of Europe and Asia has adopted OFDM for
terrestrial broadcasting of digital television.
 By Directive of the European Commission, all
television services transmitted to viewers in the
European Community must use a transmission
system that has been standardized by a recognized
European standardization body,[2]
and such a
standard has been developed and codified by the
DVB Project, Digital Video Broadcasting (DVB);
Framing structure, channel coding and modulation
for digital terrestrial television.[4]
 COFDM is also used for other radio standards, for
Digital Audio Broadcasting (DAB), the standard for
digital audio broadcasting at VHF frequencies, for
Digital Radio Mondiale (DRM), the standard for
digital broadcasting at shortwave and medium wave
frequencies (below 30 MHz).
 Ultra-wideband (UWB) wireless personal area
network technology may also utilize OFDM, such as
in Multi band OFDM (MB-OFDM). This UWB
specification is advocated by the WiMax Media
Alliance (formerly by both the Multi band OFDM
Alliance [MBOA] and the Wi Media Alliance, but the two
have now merged), and is one of the competing UWB radio
interfaces.
IV. MULTIPLE INPUTS AND MULTIPLE OUTPUTS
(MIMO)
Multiple Input/Multiple Output Pronounced "my-mo," it is
the use of multiple transmitters and receivers (multiple
antennas) on wireless devices for improved performance.
When two transmitters and two or more receivers are used,
two simultaneous data streams can be sent, which double the
data rate. Multiple receivers alone allow greater distances
between devices. For example, the IEEE 802.11n (Wi-Fi)
wireless standard uses MIMO to increase speed to 100 Mbps
and beyond, doubling at minimum the 802.11a and 11g rates.
MIMO antennas are also used in Wi MAX and LTE.
MIMO, MISO and SIMO. The M, S, I and O relate to the air,
not the device. For example, multiple inputs (MI) mean
multiple transmitters send multiple data streams "into" the air.
Multiple outputs (MO) mean multiple receivers acquire
multiple data streams "out of" the air.
Figure 1 MIMO, MISO and SIMO

4. IJASCSE, Vol 2, Issue 2, 2013
www.ijascse.in Page 42
Apr. 30
1. Functions of MIMO –
MIMO can be sub-divided into three main categories, pre
coding, spatial multiplexing or SM, and diversity coding.
 Pre coding is multi-stream beam forming, in the
narrowest definition. It is considered to be all spatial
processing that occurs at the transmitter. In (single-
layer) beam forming, the same signal is emitted from
each of the transmit antennas with appropriate phase
(and sometimes gain) weighting such that the signal
power is maximized at the receiver input. The
benefits of beam forming are to increase the received
signal gain, by making signals emitted from different
antennas add up constructively, and to reduce the
multi path fading effect.
 Spatial multiplexing requires MIMO antenna
configuration. In spatial multiplexing, a high rate
signal is split into multiple lower rate streams and
each stream is transmitted from a different transmit
antenna in the same frequency channel. If these
signals arrive at the receiver antenna array with
sufficiently different spatial signatures, the receiver
can separate these streams into (almost) parallel
channels. Spatial multiplexing is a very powerful
technique for increasing channel capacity at higher
signal-to-noise ratios (SNR).
 Diversity Coding techniques are used when there is
no channel knowledge at the transmitter. In diversity
methods, a single stream (unlike multiple streams in
spatial multiplexing) is transmitted, but the signal is
coded using techniques called space-time coding.
The signal is emitted from each of the transmit
antennas with full or near orthogonal coding.
Diversity coding exploits the independent fading in
the multiple antenna links to enhance signal
diversity. Because there is no channel knowledge
there is no beam forming or array gain from diversity
coding.
2. Applications of MIMO –
Spatial multiplexing techniques makes the receivers very
complex, and therefore it is typically combined with
Orthogonal frequency-division multiplexing (OFDM) or with
Orthogonal Frequency Division Multiple Access (OFDMA)
modulation, where the problems created by multi-path channel
are handled efficiently. The IEEE 802.16e standard
incorporates MIMO-OFDMA. The IEEE 802.11n standard,
released in October 2009, recommends MIMO-OFDM.MIMO
is also planned to be used in Mobile radio telephone standards
such as recent 3GPP and 3GPP2 standards. In 3GPP, High-
Speed Packet Access plus (HSPA+) and Long Term Evolution
(LTE) standards take MIMO into account. Moreover, to fully
support cellular environments MIMO research consortia
including IST-MASCOT propose to develop advanced MIMO
techniques, i.e., multi-user MIMO (MU-MIMO).
V. Problems with 4G –
In India, Bharti Airtel launched India's first 4G service, using
TD-LTE technology, in Kolkata on 10 April 2012. Fourteen
months prior to the official launch in Kolkata, a group
consisting of China Mobile, Bharti Airtel and SoftBank
Mobile came together, called Global TD-LTE Initiative (GTI)
in Barcelona, Spain and they signed the commitment towards
TD-LTE standards for the Asian region. The Reliance
industries will start offering 4G services probably in the
summer of this year. Sources within the RIL, headed by
Mukesh Ambani, revealed to The Economic Times that it
plans to provide 4G connectivity to 700 cities by June of this
year, which will definitely be a big step toward its developing
India.RIL will be touting speeds of up to 50–100 Mbps on its
network. Taking this into account, low costs and high speed
are the main avenues through which it will rise in the market,
with its speed being 7 times that of 3G.

5. IJASCSE, Vol 2, Issue 2, 2013
www.ijascse.in Page 43
Apr. 30
 Dr Stephen Unger, Ofcom’s chief technology officer,
said: “The research that we commissioned indicates
that early 4G mobile networks with standard
configurations will be 3.3 times (230%) more
spectrally efficient than today’s standard 3G
networks. But Ofcom also notes that “gains in cell
spectrum efficiency will not be enough to keep pace
with demand growth”
 Next generation mobile services have the potential to
cause interference issues for up to two million UK
households, the head of free view has warned.
 Homes within two kilometres (1.24 miles) of a 4G
base station are likely to experience interference and,
for some, there will also be a loss of channels.
 4G gets disconnected over and over again as it is not
widely spread. And this problem is known as teething
problem.
VI. CONCLUSION
Here we have studied the need of 4G technology and how it
provides better speed over the internet. We had also analysed
various technologies used in 4G, such as UMTS, OFDM and
MIMO. 4G is better technology among all 1G, 2G and 3G as
it provides faster speed of about 100mbps-1GBps. Its scalable
bandwidth is up to 40MHz to handle more traffic over the
internet. We have an overview of its problem too, which must
be solved soon so it can get popular and usable like internet
other technologies.
VII. REFRENCES
[1] R. van Nee, G. Awater, M. Morikura, H. Takanashi, M.
Webster, and K. Halford, “New high-rate wireless LAN
standards,” IEEE Commun.
Mag., vol. 37, pp. 82–88, Dec. 1999.
[2] Directive 95/47/EC of the European parliament and of
the council on the use of standards for the transmission of
television signals.
[3] Tindal, Suzanne (8 December 2008). "Telstra boosts Next
G to 21 Mbps". ZDNetAustralia.
http://www.zdnet.com.au/news/communications/soa/Telstra-
boosts-Next-G-to-21Mbps/0,130061791,339293706,00.htm
Retrieved 2009-03-16.
[4] ETSI Standard: EN 300 744 V1.5.1 (2004-11).
[5] “Synchronization for MIMO OFDM systems,” in Proc.
Globecom 2001, pp. 509–513.
[6] J. Tan and G. L. Stüber, “Multicarrier delay diversity
modulation for MIMO systems,” IEEE Trans. Wireless
Commun., to be published.
About Authors:
Dr.Avinash Sharma is engineering graduate from Mumbai
University and post graduate degree from BITS, Pilani and
Ph.D. in computer science and engineering with 15years of
experience. Over 100 papers including 45 national and 60
international papers are published in proceedings and journals
of national and international repute. Presently, he is working
as Principal and Professor at Advait Vedanta inst. Of
Tech,Jaipur.
Mr. Anurag Bhatnagar is a Post Graduate Student, pusuing her
M.Tech. in Computer Engineering Department, Rajasthan
Institute of Engineering & Technology, Jaipur, Rajasthan,
INDIA. He is an active researcher in the field of computer
science and information technology.