Mobile networks have evolved tremendously in last 3
Cellular concept was introduced with 1G network.
Today, 4G technology is getting ready to storm the
4G or the 4th generation communication technology is
the successor of 3g technology.
The principal change brought about by this
advancement is in the data speed which has been
of 4G is
than that of
4G is a secure integrated system which will be capable to
provide 100 Mbps data speed for high mobility devices
such as cell phones and 1 Gbps for low mobility devices
such as desktops.
These specifications were provided by the ITU-R
organization under the IMT-A (International Mobile
Telecommunications – Advanced) requirements.
4G is being developed to accommodate the quality of
service (QoS) and rate requirements set by further
development of existing 3G applications like mobile
broadband access, Multimedia Messaging Service (MMS),
video chat, mobile TV, and also new services like HDTV.
The onset of wireless communication was marked
during the Second World War in 1940s for shore-to-
ship communication using radio telephony links.
However the 1st generation cellular networks were set
up around 1977.
The nomenclature of the generations generally refers
to a change in the fundamental nature of the service,
non-backwards compatible transmission technology,
higher spectral bandwidth and new frequency bands.
New generations have appeared about every ten years
since the first move from 1980 analog (1G) to digital
(2G) transmission in 1992.
This was followed, in 2001, by 3G multi-media support,
spread spectrum transmission and at least 200 kbit/s,
and it is expected to be followed by 4G in 2012, which
refers to all-IP packet-switched networks, mobile
ultra-broadband (gigabit speed) access and multi-
* Multiplexing and access schemes:
Code, time, and frequency are generally the basis for
multiplexing any spectrum efficiently.
The first generation wireless standards used TDMA
In the wireless channels, TDMA proved to be less
efficient in handling the high data rate channels. So
the succeeding generations (2g and 3g) used CDMA
But the theoretical drawback; that a CDMA network
setup does not inherently reject new clients when it
approaches its limits, resulting in a denial of service to
all clients when the network overloads; placed a soft
limit on it.
Multiplexing scheme employed by 4g technology is
OFDMA (Orthogonal Frequency Division Multiple
In OFDM, every portion of input data is transmitted
on one of available subcarriers. In this view, OFDM
seems very similar to traditional FDM systems.
However, contrary to FDM, the spectrum of OFDM
subcarriers can interfere to each other. Therefore,
there is no need for wide guard bands to provide
reliability, as was in FDM.
To ensure restoration of transmitted symbols at the
receiver, the sub carrier frequencies should be
orthogonal to each other.
OFDMA is a multiple user version of OFDM.
This allows simultaneous data transmission from
OFDMA is a
and time domain
Slots are assigned
along the time
domain as well as
The predecessor of 4g worked on two parallel
infrastructures, packet switched and circuit switched
network nodes and supported IPv4.
By the time that 4G was deployed, the process of IPv4
address exhaustion was expected to be in its final
The newly emerged technology will be based on
packet switched only and support IPv6.
The advanced 4g technology requires advanced
MIMO technology, a branch of Intelligent Antenna
systems, is employed by 4g.
Wherein multiple antennas are used at both the
transmitter and receiver end- Thus the name Multiple
Input Multiple output (MIMO).
The terms ‘input’ and ‘output’
here refer to the channel
carrying the signal and not the
devices having antennas.
It uses the spatial multiplexing
technique for 4g transmission,
in which, a high rate signal is
split into multiple lower rate
streams and each stream is
transmitted from a different
transmit antenna in the same
At the receiver side if these
signals appear with different
spatial signatures (direction of
arrival), they are separated
into parallel channels.
3G in India: Late entry quick exit
India was almost a decade late in adopting the 3g
communication technology on a massive scale.
With its global launch in 2001, 3g technology was seen
in India only in December 2008, provided by
government owned MTNL and a little later by BSNL
(also government based).
The 3g spectrum auction, for private sectors, took
place in India on 9 april,2010.
And launch of 3g by private sectors was as late as 2010.
However that is not the case expected with the set in of
4g communication technology. Indian telecom
minister, Kapil Sibal, expects 4g to hit Indian network
by later half of 2013.
Reasons for delay in 3G launch
As compared to 2g, which require a bandwidth of 30-
200KHz, 3g telecom service required much higher
frequency range, about 15-20 MHz.
This increased the bandwidth requirements manifold.
Thus it required the network providers to acquire new
licenses for the frequency spectrum, which in turn
increased the cost of transmission.
A high tariff for using 3g data services was a prime
reason why 3g failed to become popular among the
Long term evolution (LTE)
technology, or 4G, allows more data
to be transferred over the same
bandwidth used by 3G but at higher
Compared with a speed of 3 megabits
per second (Mbps)Offered by third-
generation services, LTE can offer
speeds up to 10Mbps.
As a result, service providers should
be able to get more data transfer out
of their network and possibly lower
the cost to run their networks.
Impact of 4G on India
A. Government Organization
With the use of 4G technology the performance of the
organization will improve by
a) Reducing cost of travel
b) Instant access to monitor performance of any
c) Instant update on all government projects
implemented and work in progress
d) Increased revenues by auctioning spectrum
B. Educational Institutions
a) Wider spectrum of use,
quickly tracking student
and teacher performance
b) Evaluation of practices
followed in education
c) Video conferencing with
d) Online guest lectures
e) Infrastructure tracking
f) Online tutoring
C. Electronics Industry
a) An escalation in demand for new products
b) New enterprises will emerge
c) Competition will increase
D. Telecommunication Sector
a) New markets emerge with new demand for
b) New market strategies will be required
E. Citizens & Private Organizations
a) Can watch videos
with HD quality
b) High quality video
c) Many more business
trips can be avoided
d) High quality video
e) Can track each and
every move of an
F. Banking services industries
a) Mobile banking will be efficient and secure than
b) Virtual draft and cheque may exists in future
a) Online diagnosis
b) Specialist Doctors
can be consulted
situations can be