Overview On Wireless Communication

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A Gateway to Digital Bangladesh

1.0  
Introduction

This is a study of wireless
communication and networking as a gateway to digital Bangladesh in the
perspective of the country and its available resources.

Digital Bangladesh is a dream for
a system based on technology for management, administration and governance to
ensure transparency, accountability and answerability at all levels of society
and state. It signifies the availability of all information to all citizens at
all times. To make this possible all citizens must be connected by a net of
technology. In other words an advanced communication system is required.

Currently in the perspective of
Bangladesh it can be said that in terms of communication the country is still
lagging in the dark ages. The country is still using back-dated wired
communication systems and primitive forms of wireless technology. This is a
waste of available technology of the present day. It is also highly inefficient
as it does not allow transfer of information as fast as might be possible. Wired
communication has the drawback that it is not easily accessible in all kinds of
terrain. To carry on using these forms of technology would be a severe
hindrance to setting up a truly digital nation.

In that context this study was
carried out to find the different types of advanced wireless communications
systems available this day, analyze their respective qualities, speeds and
efficiencies and to give a general outline for the setting up of the most
feasible of the technologies in case of Bangladesh.

In gathering data, questions were
set to analyze whether advanced technology is really necessary at the time
being and whether or not people would be willing to move on to advanced
technology considering the obvious cost increase in the initial stages. Based
on information gathered it was deduced that most people who are not yet under
wireless communication would like to join in sooner rather than later while a
vast majority would rather have adequate returns for their money in the form of
a standard communication system rather than an obsolete system.

In the following pages the data
of the different types of wireless technologies, their comparisons, the present
infrastructure in Bangladesh and the possible future steps are upheld.

2.0
Wireless Technology

In the
modern world wireless technology is the most advanced way to connect with each
other. Its superiority over wired technologies is inherently obvious. Wired
technology fails in various landscapes. Mountains, plateaus, remote areas all
of these are places where wired technology can never reach despite the best
efforts. Wireless technology is not hindered by any of these problems due to
its work at range effect. The relative size of wireless devices is also small
which makes them easy to carry, low of cost and easy to run and maintain. Also
the mobility afforded by wireless technology is most important in the modern
day perspective.

Almost
all wireless technologies follow the same working process. A base tower must be
set up, from which the wireless signal will be distributed. The signal is received
by and antenna in the users device which is processed and then reproduced as
data or audio or visual aid which is understandable to the user. The user can
then produce his own feedback which will be returned to the base via the same
route. The signals propagate at the speed of light which makes the transfer of
data unimaginably fast. It is this aspect of wireless communication which makes
it so desirable to bring a country forward into the digital age.

Though
the general concept is same, based on different signal bandwidths, data
transfer rates, range of transmission and energy consumption there are quite a
few types of wireless networks available at the present time. Set up costs of
these different systems also vary widely. A description of these different
technologies along with a comparison follows.

2.1 GSM

 GSM stands for Global System for Mobile
Communication. It is a cellular network which means that cell phones connect to
it by searching for cells/bases in the immediate vicinity. One of the key
features of GSM is the Subscriber Identity Module (SIM), a detachable smart
card containing the user’s subscription information. This allows each person
access to his or her own personalized network.

GSM has
been upgraded recently to GPRS (General Packet Radio Service) and even more
recently to EDGE (Enhanced Data Rates for GSM Evolution). All of these
technologies transmit their signals in the frequency bandwidth of 900 MHz to
1800 MHz’s. The range of a typical base station would be about 10-15 miles.

GSM
features include “always on” internet access, point to point service or
interworking with the internet, push to talk over cellular and multimedia
messaging service. Its major disadvantage is its low data transfer rate with
the best of GPRS systems reaching a transfer rate of 30 SMS per minute.

However
at the moment the GSM/EDGE system is the most widely used system available. Relatively
low cost for set up and maintenance as well its large range makes it suitable
as a startup system for further upgrading at later times. But as its signal
gets crowded out faster transfer rates and larger bandwidth is necessary. Yet
still at the moment there are 413 GSM/EDGE networks in 177 countries with
79.674 million users of GSM/EDGE system in Bangladesh.

2.2 CDMA

CDMA is
the
abbreviation of Code
Division Multiple Access
.
It is a wireless technology almost similar to GSM but with a few technical
differences. While the GSM system uses a continuous signal the CDMA system uses
a packet system for transmission of signals. The signal is first broken down
into a seemingly random code which is then sent to the receiver along with the
necessary rebuilding code. The receiver is then able to re-assemble the code
and produce it in an understandable way. The code sent over CDMA technology can
be digitized voice
, ISDN channel, internet data etc.

The
use of an independent code and synchronous reception allows multiple users to
access the same frequency band at the same time
. This gives it very large advantage since jamming
up of the signal rarely occurs. It also makes the system highly efficient and
its transfer speed means that it doubles its output in the same time
corresponding to GSM. However it has its drawbacks too.
The
signal occupies a bandwidth much greater than that which is necessary to send
the information
.
This means that any base station must be built to withstand the extra bandwidth
necessary. Also the extra usage of bandwidth means extra cost. CDMA devices
have low battery life since high transfer rates mean higher energy consumption.
CDMA signals also have a problem that they tend to cause self interference
sometimes disrupting communications. This also means that audio type and data
types cannot be sent at the same time.

The range of a typical CDMA base
station is in the range of 100 miles while its data transfer rate can range in
2Mbit/s.

2.3 3G

The 3G network
is the third generation of mobile networking and telecommunications. It
features a wider range of services and advances network
capacity over the previous 2G network.

3G
has provided a new way of life among mobile phone, handset and computer users.
3G is changing the way one looks at network, with the various features and
effects.


3G represents a paradigm shift from the voice centric world of the previous
generations of wireless networks to the multi-media centric world of 3G.
Reflecting the high 3G bandwidth and the fact that it is packet based, 3G
devices will offer capabilities that are a combination of a phone, PC, and a
TV.

With
3G technology, one can get to enjoy data transmission speed leading up to 2Mbit/s,
It also gives you high degree of connectivity and higher networking, plus
resistance to noise. The technology has enhanced the bit rate, allowing service
providers to give high speed internet facilities. Silicon Press notes that 3G
is more than 10 times faster than the maximum speed of 2G devices for its
higher bandwidth. Another advantage of 3G technology is that it can utilize
packet-based Internet protocol connectivity. This means mobile devices will
always be online and ready for Internet access. But, one does not have to
actually pay for the connection until he starts sending or receiving data
packets, such as sending an email or looking at a webpage. 3G is also great
with its security.
It
offers greater security than their 2G predecessors.

However
to support 3G technology, updates need to be made to the current cellular
infrastructure. According to 3G Internet, this means installing new 3G
equipment at every current cellular base station and acquiring new frequencies
for 3G transmissions. Besides, new base stations are needed to be built closer
because 3G yet maintains a lower range than predecessors. Both of these
undertakings are extremely expensive and could take a long time to complete
fully. In addition, in order to utilize all of the new features 3G technology
has to offer, customers must purchase 3G-compatilible handsets, which are
generally more expensive than their 2G counterparts. In addition to being more
expensive, 3G handsets also require more power than most 2G models. These
limitations do not make 3G the most desirable for initial set up.

2.4 WiFi

WiFi is the abbreviated form of wireless-fidelity.
WiFi is the mechanism for wirelessly connecting electronic devices to the
internet via wireless network points. The WiFi technology available today
extensively uses the IEEE 802.11 standards. WiFi can be set up anywhere using a
router modem from a wired network using any of the IEEE standards. Currently
most in use is the IEEE 802.11g standard router.

WiFi uses a 2.4 GHz signal to connect
devices over 11 to 13 channels throughout the range. The IEEE 802.11g standard
allows a data transfer rate of 6-54 MBit/s over a range of 140 meters while the
newer IEEE802.11n standard allows from 7.2-72.2 MBit/s over 250 meters. Range
of WiFi signal ranges about 32 meters indoors. For long distance signals WiFi
range can be extended by using special antennas. Currently under test is the
WiLD(WiFi over Large Distances) system, which allows data to be sent over 5-15
km region. WiFi is considered much more secure than other wireless networks.
The previous standard of WEP having failed, WPA2 security system was created in
2010 which till date has been found to be secure provided the password is
strong.

However WiFi has its disadvantages as
well. It has a very short range in comparison to other technologies. It is very
sensitive to interference and as very poor signal penetration. Hence its
antenna’s must be placed high above ground level, sacrificing some of its
already limited range. As well as that WiFi consumes huge amount of power to
provide the high rate of data transfer possible. This causes serious problem to
hand-held devices reducing their battery life. Yet still WiFi is gaining in
popularity and about 700 million people use WiFi nowadays worldwide.

2.5 WiMAX

WiMAX Technology is also one of
the emerging wireless technologies that provide us high speed mobile data and
telecommunication services. WiMAX stands for Worldwide Interoperability for
Microwave Access and it is based on IEEE 802.16 standards. WiMAX provides very
good signals therefore higher data rate can be achieved with multiple antennas.
There is no need for line of sight connection between subscriber terminals and
the base station in WiMAX technology and it can support hundreds if not
thousands of subscribers from a single base station. WiMAX Technology works
same as WiFi does but it is more improved and efficient then Wi-Fi and also
permits usage at much greater distances. It is a part of a “fourth generation,”
of wireless-communication technology.

The most suitable frequency band
for WiMAX is 3.5 GHz, followed by 2.2-5.2 GHz band. It is expected that a
2.5-2.7 GHz band could be used for some countries. WiMAX far surpasses the
30-metre (100-foot) wireless range of a conventional Wi-Fi local area network
(LAN), offering a metropolitan area network with a signal radius of about 50 km
(30 miles). WiMAX offers data-transfer rates of up to 75 Mbit/s, which is
superior to conventional cable-modem and DSL connections technology. WiMAX is
sometimes referred to as “WiFi on steroids” and can be used for a number of
applications including broadband connections, cellular backhaul, hotspots, etc.

Cost of deployment of WiMAX depends
how it will be used. There are two ways WiMAX can be implemented – as a zone
for wireless connections that single users go to when they want to connect to
the Internet on a laptop (the non-line-of-sight “super WiFi” implementation),
or as a line-of-sight hub used to connect hundreds of customers to a steady,
always-on, high-speed wireless Internet connection. Under the “super WiFi”
plan, cities might pay to have WiMAX base stations set up in key areas for
business and commerce and then allow people to use them for free. They already
do this with WiFi, but instead of putting in a bunch of WiFi hot spots that
cover a few hundred square yards, a city could pay for one WiMAX base station
and cover entire financial district.

2.6
Comparison

Technology

Transfer Rate

Range

Bandwidth

Setup Cost

Maintenance Cost

Energy Consumption

Security

GSM

200Kbit/s

15 Km

900-1800 MHz

Low

Low

Low

Low

CDMA

2Mbit/s

100 Km

1.25 MHz

Low

High

High

Low

3G

2Mbit/s

15 Km

900-1800MHz

High

Low

Medium

High

WiFi

Up to 50 Mbit/s

5 Km

2.4 GHz

High

Low

High

High

WiMAX

75Mbit/s

50 Km

3.5 GHz

High

High

Medium

High

3.0 Present
Infrastructure  

Though not yet a fully digital
nation, Bangladesh already has a very good infrastructural backbone on which to
complete its digitalization. Even though most of the communication systems are
currently wired networking, the future plans which have already been set into
motion point to the necessity of wireless networks and availability of this
network to the mass people. The existing technology of communication in case of
our country and the future plans to involve all citizens in networking are
upheld in following points, which points invariably to the necessity of
wireless networking in the country.

3.1 Existing
Technology

The situation of mobile phones in
Bangladesh is seeing a very fast growth spurt, with a rate of almost 30%
increase per year. There are 6 operators functioning at the moment in
Bangladesh, 5 of these using GSM/EDGE technologies while the remaining 1 uses
CDMA technology. Their coverage at the moment is just on the boundary of
standard, as their range covers almost all of the country. However quality of
their service is currently not up to world standard. Keeping their existing
technology and expecting a greater service would be highly improbable.
Upgrading to newer and better technologies will not be too costly due to the
fact that their initial set up has already been completed.

WiMAX has just been introduced into
the country on a private basis however its range is still very limited, while
the introduction of 3G is facing some indecision on behalf of the government.
Yet at the moment the country has been connected to the Sub-Indian Ocean
submarine cable allowing connectivity up to 43.8 Gbit/s. this opens up the
horizons for setting up high–speed networks like WiFi which are based on a
wired backbone.

3.2 Existing Future Plans

Future plans on behalf of the
government to uplift Bangladesh to the status of digital nation includes  :

1.
Development
of Wireless industry and it services  by
providing all possible assistance to talented young people.

2.
Inclusion
of compulsory IT education at secondary level by 2013.

3.
Set
up of High-tech Park, software Technology Park, ICT incubator and computer
villages in the country.

4.
Digital
government for citizen services with the help of wireless communication.

5.
Creation
and distribution of digital content through choosing suitable wireless
platforms. (TV, Radio, video, community radio etc.)

6.
Establishment
of low cost wireless communication services for connecting citizens.

7.
Establishment
of E-Citizen services which requires innovative service design; suitable
delivery channel.

8.
Establishment
of wireless technology in business which requires access to market; promotion
of ICT Business to support Digital Bangladesh; promotion of software and ITES
services; Support other component of digital Bangladesh.

9.
Increasing
telecom access, and internet users through mobile.

10.  Informative and interactive
websites of all the entities under Ministry of Education.

11.  Bringing schools and colleges
under wireless communication very soon.

All of these plans point to the
necessity of wireless communication to allow people access to mass information.

4.0 Conclusion

We the people of 21st
century are now dreaming for a digital Bangladesh. But it will be wrong if
anyone thinks that digital Bangladesh is a matter of time without taking proper
steps. The whole process requires lots of tasks, for which we have to be
prepared. After all, digitization is the only pathway to economic success,
quality education, public health and also generating transparency in governance
with full public participation. So, our goal is how we build this digital
Bangladesh.

To pave the way of digital
Bangladesh, the very first thing would be to ensure the connectivity of
Information and Communication Technology all over the country disregarding
urban rural barrier or rich poor divide. Everyone should be given access to the
reach of information. In that case we must need a strong communication network
which will give people easy, instant, cheap and fast access to information. And
there is no rival of wireless network system on this regard.

Wireless communication is a rapidly
growing segment of the communication industry, with the potential to provide
high-speed high-quality information exchange between portable devices located
anywhere in the world. It has the ability to reach the remote area of our
country with its advantages which a wired communication system does not have.
So, our necessary information and connection will be available whenever we
need.

Though there are lots of challenges
to set up a countrywide wireless network system, pre-planned and intelligent
steps will be able to go over all the obstacles of our way and we will be able
to proceed to our dream, digital Bangladesh. The more we will be digitalized
the more the country will be vulnerable in terms of security and governance.

5.0 Recommendations

5.1 Suggestions

1.
Based
on the existing infrastructure it would be wise to emphasize on the GSM network
for the non distant future. First of all network for everybody should be
ensured before speed or quality of coverage.

2.
For
a future plan rather than upgrading via an obsolete system to reduce cost, it
would be preferable to incorporate up-to-date technology.

3.
Comparing
the speed of coverage available the suggestion would be to target a 3G system.

4.
Due
to the cost of set up it would be unwise to look for a purely governmental set
up to bring everyone under wireless coverage. Private sector should be
encouraged to supply their  own
technology.

5.
Based
on quality, security and range of systems it would be recommended to use WiFi
systems as a low cost alternative in small regions where high quality is
needed. However its high power consumption does not make it suitable for
wide-spread use in a country like Bangladesh.

5.2 Precautions

1.
Government
policy should be fixed with a set goal in mind also with a fixed time schedule.
Taking too much time to set up an infrastructure might lead to the technology
becoming obsolete and unworthy of use in the face of more modern technology.
However planning keeping in mind the possibility of upgrading the system would
reduce unnecessary wastage of resources. 

2.
Complete
wireless technology would be highly unfeasible for Bangladesh. A wireless
network built on a back bone of wired networking would be the best solution.
However that means a strong wired network must be built up first to support the
wireless network.

3.
To
supply necessary security and availability of network the set up of the
infrastructure i.e. towers, wired backbone and bandwidth must be made as secure
as possible.

4.
Environmental
hazards due to the set-up of wireless towers and antennas must be kept in mind
while setting up the system. Radiation contamination, pollution and risks must
be brought into consideration before implementing any plan.

1.
Wired
technology is providing better speed and quality. But, it is not able to go to
the remote corners of our country. So for the coverage of all area of our
country with a network system wireless system is more preferable.

2.
It
is true that, once wired technology provided more security than wireless
technology. But, recent technological improvement has overcome this barrier and
wireless technology now provides enough security.

3.
There
is a strong possibility of environmental hazard by wireless communication
because of its radiation. Again, it will be difficult to bring transparency to
all information without wireless. So wireless network system should be set up
keeping the hazard at a minimum.

4.
Initial
cost for wireless communication is really high. But we should consider the
future advantages and the moving world. Unless it is implemented sooner than
later the emergence of Bangladesh as a digital nation will not be achieved.

5.
It
will be a challenge for the young generation to keep aloof themselves from the
different dark attractions of the internet if they have the instant access to
it. Awareness, carefulness and proper management will be able to control the
situation.