The 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 kilometers for radio communications). The
technologies have been classified according to their generation, which largely
specifies the type of services and the data transfer speeds of each class of
technologies.
o It was
wireless Telephone technology and mobile Telecommunication introduced in
1980's. 1G networks used analog signals, as opposed to digital signals used by
all the successive generations of mobile technologies.
o In 1G
networks, voice calls were simply modulated to a higher frequency, typically to
150 MHZ and up.
o The
first commercially available cellular network using 1G standard was introduced
by NTT in the year 1979 in Japan.
2G - The Second Generation
o It was
commercially launched for the GSM standard in 1991 by Radiolinja, currently
known as Elisa Oyj in Finland.
o 2G
allowed for enhanced data services and also introduced the Short Messaging
Services (SMSs). Since, the introduction of 2G, voice communication were
digitally encrypted.
o Two
revisions or additions to this generation are referred to as 2.5 G and 2.75 G.
The combined usage of GPRS and CDMA networks collectively came to be known as
2.5G. WAP (Wireless Application Protocol) and MMS (Multi Media Messaging) were
introduced, along with Internet services.
3G - The Third Generation
o The
third generation was introduced by NTT DoCoMo in Japan in 2001. Although
Limited in scope, initially it was a leap forward.
o 3G data
transfer rattes are 384 k bits to 2 M bits, so it allows for never before
services like video calls, video conferencing, mobile TV, online gaming
etc.
4G-The Fourth Generation
o The
next generation, 4G mobile phones are all set to provide data transfer rates of
100 Mb/sec to 1Gb sec, which is mind boggling.
o It is a
successor to 3G and 2Gfamilies of standards. The nomenclature of the
generations generally refers to a change in the fundamental nature of the
service, non-backwards compatible transmission technology and new frequency
bands. The first was the move from 1981 analogue (1G) to digital (2G)
transmission in1992. This was followed, in 2002, by 3G multi-media support,
spread spectrum transmission and at least 200 kbit/s, soon expected to be
followed by 4G, which refers to all-IP packet-switchednetworks, mobile
ultra-broadband (gigabit speed) access and multi-carrier transmission.
Pre-4Gtechnologies such as mobile WiMAX and first-release 3G Long Term
Evolution (LTE) have been available on the market since 2006and 2009
respectively.
5G-The 5th Generation
o It is a
term used in some research papers and projects to denote the next major phase
of mobile telecommunication standards beyond the current 4G/IMT-Advanced
Standards.
Who made India's first cell-phone call ?
In August 1995, Chief Minister of West Bengal, Shri Jyoti Basu ushered
in the cellphone revolution in India by making the first call to Union Telecom
MinisterSukhram (this
call was made between Writer's Building in Kolkata and Sanchar Bhavan in
Delhi). This call was carried on the network of Mobile Net. The day also saw
the introduction of Internet in the country, starting with Mumbai, Calcutta,
Chennai and Pune.