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Has it ever struck your curious mind how 4G evolved from simple Push to talk system ?
Is there any governing body which regulates the spectrum ?
what kind of services we will have in next generation of communication?
So friends, Lets start the journey of wireless communication.
Mobile radio telephones were introduced for military communications in the early 20th
century. Car-based telephones was first tested in Saint Louis in 1946. This system used a
single large transmitter on top of a high rise building. A single channel was used for
sending and receiving similar to a half duplex system. To talk, the user pushed a button
that enabled transmission and disabled reception. Due to this, these became known as “push-to-talk”
systems in the 1950s. To allow users to talk and listen at the same time, IMTS (Improved
Mobile Telephone System) was introduced in the 1960s. It used two channels one for sending
and one for receiving bringing telecommunication to full duplex mode.
In the 1970s Private companies have started developing their own systems to evolve the
existing further..Those private systems are Analogue Mobile Phone System, used in America,
Total Access Communication System and Nordic Mobile Telephone, used in parts of Europe
and Japanese Total Access Communication System, used in Japan and Hong Kong.
Independently developed systems are called as 1st Generation communication. It was introduced
in 1982 by Bell Labs and popularly known as Advanced Mobile Phone System (AMPS). The key
idea here was to divide geographical areas into cells. and each cell was served by a
base station so that frequency reuse can be implemented. As a result AMPS could support
5 to 10 times more users than IMTS. Major concern for the 1st generation was weak Security
on air interface, full analog mode of communication. and No roaming.
Now, To implement roaming. Individual organisations started working under one umbrella, European
Telecommunications Standards Institute (E T S I) and developed 2nd Generation system.
Second generation cellular telecom networks were commercially launched in 1991 in Finland
based on GSM standards. It could deliver data at the rate of up to 9.6 Kbps.
Three primary benefits of 2G networks over their predecessors were.
phone conversations were now digitally encrypted. It was significantly more efficient on the
spectrum and allowed far greater mobile phone penetration level.
2G introduced data services for mobile, starting with SMS text message.
Further To achieve higher data rates GSM carriers started developing a service called General
Packet Radio Service (GPRS). This system overlaid a packet switching network on the existing
circuit switched GSM network. GPRS could transmit data at up to 160 Kbps
The phase after GPRS is called Enhanced Data Rates for GSM Evolution (EDGE). It introduced
8 PSK modulation and could deliver data at up to 500 Kbps using the same GPRS infrastructure.
During this time the internet was becoming popular and data services were becoming more
prevalent. Post 2.5G, Multimedia services and streaming started growing and Phones now
started supporting web browsing. Development of 3G,
3GPP UMTS, the Universal Mobile Telecommunications System succeeded EDGE in 1999.This system
uses Wideband CDMA ( W-CDMA) to carry the radio transmissions, and often the system
is referred to by the name WCDMA.
Now before we go further let us understand how the governing bodies were developed.
In the interests of producing truly global standards, the collaboration for both GSM
and UMTS was expanded further from ETSI to encompass regional Standards Development Organizations
such as ARIB and TTC from Japan, TTA from Korea, ATIS from North America and CCSA from
China. The successful creation of such a large and
complex system specification required a well-structured organization. This gave birth to 3GPP and
which worked under the observation of ITU-R. ITU-R is one of the sector of ITU, Its role
is to manage the international radio-frequency spectrum and to ensure the effective use of
spectrum. ITU-R defines technology families and associates specific parts of the spectrum
with these families. ITU-R also proposed requirement for radio technology.
3 organization started developing standards to meet the requirements proposed by ITU-R.
3GPP, 3GPP2, IEEE Evolution of 3gpp, started from GSM to Long
term evolution Advanced. Evolution of 3GPP2, started from IS95 to CDMA
Revision B. Evolution of IEEE started from 8o2.16 Fixed
Wimax, to 8o2.16M
Since 3GPP was dominated and widely accepted, we will only incorporated roadmap evolved
by 3GPP.
Now coming back to 3rd Generation. The goal of UMTS or 3G wireless systems was
to provide a minimum data rate of 2 Mbit/s for stationary or walking users, and 384 kbit/s
in a moving vehicle. 3GPP designated it as Release 99.
The upgrades and additional facilities were introduced at successive releases of the 3GPP
standard. Release 4: This release of the 3GPP standard
provided for the efficient use of IP, this was a key enabler for 3G HSDPA.
Release 5: This release included the core of HSDPA. It provided reduced delays for downlink
packet and provided a data rate of 14 Mbps. Release 6: This included the core of HSUPA
with a reduction in uplink delay it enhanced uplink raw data rate of 5.74 Mbps. This release
also included MBMS for broadcasting services. Release 7: This release of the 3GPP standard
included downlink MIMO operation as well as support for higher order modulation of up
to 64-QAM. Either MIMO or 64-QAM could be used at a time.Evolved HSPA provides data
rates up to 28 Mbit/s in the downlink and 11 Mbit/s in the uplink.
This brings us to the most awaited part. Long term evolution (LTE)
Initial goal of telecommunication was mobility and global connectivity, but as the technology
evolved the Services started expanding. Now Services were not restricted to Voice and
SMS only. For This expansion and efficient execution in LTE, whole new architecture was
adopted for both non Radio part ( SAE System Architecture Evolution) and Radio part using
pure IP Architecture (packet switching)
To fulfill the requirement proposed by ITU-R, Study group formed and LTE standardization
began in 2004. Large number of telecom companies collaborated to achieve their common vision.
In June 2005 Release 8 was finally crystallized after series of refining.
Some of the significant features of Release 8 were-
• reduced delays, for both connection establishment and transmission latency;
• increased user data throughput; • increased cell-edge bit-rate, for uniformity
of service provision; • reduced cost per bit, implying improved
spectral efficiency. • simplified network architecture;
• seamless mobility, including between different radio-access technologies;
• reasonable power consumption for the mobile terminal.
These requirements were fulfilled by advancement in the underlying mobile radio technology.
The three fundamental technologies that have shaped the LTE radio interface design were:
multicarrier technology, multiple-antenna technology, and the application of packet-switching
to the radio interface.
As a result of intense activity by a larger number of organisations, the specifications
for the Release 8 was completed by December 2007. The first commercial deployment took
place by the end of 2009 in northern Europe.
In The subsequent releases multiple services such as Multi Cell HSDPA, HETNET, Coordinate
Multipoint, Carrier Aggregation, Massive MIMO and many more were targeted for a rich customer
experience.
Now it's time to move from services to multiservices approach, in other word from LTE Advanced
to next Generation communication system which is 5th Generation.
Features have been planned to be added in the 5th Generation Or next generation systems
are, Pervasive networks : where a user can concurrently
be connected to several wireless access technologies and seamlessly move between them.
Group cooperative relay: This is a technique that is being considered to make the high
data rates available over a wider area of the cell.
Cognitive radio technology: it would enable the user equipment / handset to look at the
radio landscape in which it is located and choose the optimum radio access network, modulation
scheme and other parameters to configure itself to gain the best connection and optimum performance.
Smart antennas: Another major element of any 5G cellular system will be that of smart antennas.
Using these it will be possible to alter the beam direction to enable more direct communications
and limit interference and increase overall cell capacity.
So friends, here we have covered history of wireless communication starting from single
channel based Push to Talk system to, multiple services based purely advanced digital communication
system. In the future videos we will start exploring
fundamental of advanced communication which will help us to understand next generation
system better. Don't forget to subscribe to our channel,
like our videos and comments your views, or suggestions. Thanks for watching