10-12-2012, 01:07 PM
Generations of Wireless Technology
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Abstract
Wireless communication is the transfer of information over a
distance without the use of enhanced electrical conductors or
"wires”. The distances involved may be short (a few meters as in
television remote control) or long (thousands or millions of
kilometres for radio communications). When the context is clear,
the term is often shortened to "wireless". It encompasses various
types of fixed, mobile, and portable two-way radios, cellular
telephones, Personal Digital Assistants (PDAs), and wireless
networking. In this paper we will throw light on the evolution and
development of various generations of mobile wireless technology
along with their significance and advantages of one over the
other. In the past few decades, the mobile wireless technologies have
experience of various generations of technology revolution &
evolution, namely from 0G to 4G.
INTRODUCTION
In 1895, Guglielmo Marconi opened the way for modern
wireless communications by transmitting the three-dot Morse
code for the letter ‘S’ over a distance of three kilometres using
electromagnetic waves. From this beginning, wireless
communications has developed into a key element of modern
society. Wireless communications have some special
characteristics that have motivated specialised studies. First,
wireless communications relies on a scarce resource – namely,
radio spectrum state. In order to foster the development of
wireless communications (including telephony and
Broadcasting) those assets were privatised. Second, use of
spectrum for wireless communications required the
development of key complementary technologies; especially
those that allowed higher frequencies to be utilised more
efficiently. Finally, because of its special nature, the efficient
use of spectrum required the coordinated development of
standards.
WHY WE USE WIRELESS COMMUNICATION
There are several kinds of wireless technologies; the main
difference being their range. Some offer connectivity over an
area as large as your desktop whilst others can cover a
medium-sized office space.
Our most familiar wireless network, the mobile phone, covers
whole continents.
Wireless technology can offer businesses more flexible and
inexpensive ways to send and receive data.
FIRST GENERATION (1G)
1G (or 1-G) is the first-generation wireless telephone
technology, cellphones. These are the analog cellphone
standards that were introduced in the 1980s.It refers to the
generation of wireless telecommunication technology, more
popularly known as cellphones.1G technology replaced 0G
technology, which featured mobile radio telephones and
such technologies as Mobile Telephone System (MTS)
Advanced Mobile Telephone System (AMTS).
Its successor, 2G, which made use of digital signals, 1G
wireless networks used analog radio signals. A voice call gets
modulated to a higher frequency of about 150MHz and is
transmitted between radio towerswith the help of 1G. This is
done using a technique called Frequency-Division Multiple
Access (FDMA).
SECOND GENERATION (2G-2.75G)
2G (or 2-G) is the second-generation wireless telephone,
which is based on digital technologies. 2G networks is
basically for voice communications only, except SMS
messaging is also available as a form of data transmission for
some standards. Second generation (2g) telephone
technology is based on GSM or in other words global system
for mobile communication. Second generation was launched
in Finland in the year 1991. 2G network allows for much
greater penetration intensity. 2G technologies enabled the
various mobile phone networks to provide the services such as
text messages, picture messages and MMS (multi media
messages). 2G technology is more efficient. 2G technology
holds sufficient security for both the sender and the receiver.
All text messages are digitally encrypted. This digital
encryption allows for the transfer of data in such a way that
only the intended receiver can receive and read it. Second
generation technologies are either time division multiple
access (TDMA) or code division multiple access (CDMA).
TDMA allows for the division of signal into time slot
GSM (Global System for Mobile Communication)
GSM or global system for mobile communication is a digital
cellular system. It was originated in Finland Europe .however
now it is throughout the world. GSM (Global System for
Mobile Communication) accounts for 80% of total mobile
phone technologies market. There are over more than 3 billion
users of GSM (Global System for Mobile Communication)
now. GSM technology got its popularity, when people used it
to talk to their friends and relatives. The use of GSM (Global
System for Mobile Communication) is possible due to the
SIM (subscribers identity module) GSM (Global System for
Mobile Communication) is easy to use, affordable and helps
you carry your cell phone everywhere. GSM (Global System
for Mobile Communication) is a 2G technology. There are
many frequency ranges for GSM (Global System for Mobile
Communication) however 2G is the most used frequency.
GSM (Global System for Mobile Communication) offers
moderate security. It allows for encryption between the end
user and the service base station. The use of various forms of
cryptographic modules is part of GSM technology.