Early predecessors of cellular phones included radio
communications from ships and trains. The race to create truly portable
telephone devices began after World War II, with developments taking place in
many countries. The advances in mobile telephony have been traced in successive
generations from the early "0G" services like the Bell System's -
Mobile Telephone Service and its successor, Improved Mobile Telephone Service.
These '0G' systems were not cellular and could support few calls, and were very
expensive.
The first handheld mobile cell phone was demonstrated by
Motorola in 1973. The first commercial automated cellular network was launched
in Japan by NTT in 1979. In 1981, this was followed by the simultaneous launch
of the Nordic Mobile Telephone (NMT) system in Denmark, Finland, Norway and
Sweden. Several other countries then followed in the early to mid-1980s.
These '1G' systems could support far more calls but still used analog
technology.
In 1991, the second generation (2G) digital cellular
technology was launched in Finland by Radiolinja on the GSM standard, which
sparked competition in the sector as the new operators challenged the incumbent
1G network operators.
Ten years later, in 2001, the third generation (3G) was
launched in Japan by NTT DoCoMo on the WCDMA standard.
This was followed by 3.5G, 3G+ or turbo 3G enhancements based on the high-speed packet access (HSPA) family, allowing UMTS networks to have higher data transfer speeds and capacity.
By 2009, it had become clear that, at some point, 3G
networks would be overwhelmed by the growth of bandwidth-intensive applications
like streaming media. Consequently, the industry began looking to data-optimized
4th-generation technologies, with the promise of speed improvements up to
10-fold over existing 3G technologies. The first two commercially available
technologies billed as 4G were the WiMAX standard (offered in the U.S. by
Sprint) and the LTE standard, first offered in Scandinavia by TeliaSonera
Analog Celular Network
and phone-to-network signaling. The rise in mobile phone usage as a result of 2G was explosive and this era also saw the advent of prepaid mobile phones.
Analog Celular Network
The first automatic analog cellular systems deployed were
NTT's system first used in Tokyo in 1979, later spreading to the whole of
Japan, and NMT in the Nordic countries in 1981.
The first analog cellular system widely deployed in North
America was the Advanced Mobile Phone System (AMPS). It was commercially
introduced in the Americas in October 1983, Israel in 1986, and Australia in
1987. AMPS was a pioneering technology that helped drive mass market usage of cellular
technology, but it had several serious issues by modern standards. It was
unencrypted and easily vulnerable to eavesdropping via a scanner; it was
susceptible to cell phone "cloning;" and it used a Frequency-division
multiple access (FDMA) scheme and required significant amounts of wireless
spectrum to support.
On 6 March 1983, the DynaTAc mobile phone launched on the
first US 1G network by Ameritech. It cost $100m to develop, and took over a
decade to reach the market. The phone had a talk time of just half an hour and
took ten hours to charge. Consumer demand was strong despite the battery life,
weight, and low talk time, and waiting lists were in the thousands.
Many of the iconic early commercial cell phones such as the
Motorola DynaTAc Analog AMPS were eventually superseded by Digital AMPS
(D-AMPS) in 1990, and AMPS service was shut down by most North American
carriers by 2008.
Digital Mobile Network 2G
In the 1990s, the 'second generation' mobile phone systems
emerged. Two systems competed for supremacy in the global market: the European
developed GSM standard and the U.S. developed CDMA standard. These differed
from the previous generation by using digital instead of analog transmission,
and also fast out-of-b
and phone-to-network signaling. The rise in mobile phone usage as a result of 2G was explosive and this era also saw the advent of prepaid mobile phones.
In 1991 the first GSM network (Radiolinja) launched in
Finland. In general the frequencies used by 2G systems in Europe were higher
than those in America, though with some overlap. For example, the 900 MHz
frequency range was used for both 1G and 2G systems in Europe, so the 1G
systems were rapidly closed down to make space for the 2G systems. In America
the IS-54 standard was deployed in the same band as AMPS and displaced some of
the existing analog channels.
In 1993, IBM Simon was introduced. This was possibly the
world's first smartphone. It was a mobile phone, pager, fax machine, and PDA
all rolled into one. It included a calendar, address book, clock, calculator,
notepad, email, and a touchscreen with a QWERTY keyboard. The IBM Simon had a
stylus you used to tap the touch screen with. It featured predictive typing
that would guess the next characters as you tapped. It had apps, or at least a
way to deliver more features by plugging a PCMCIA 1.8 MB memory card into the
phone.
Coinciding with the introduction of 2G systems was a trend
away from the larger "brick" phones toward tiny 100 – 200 gram
hand-held devices. This change was possible not only through technological
improvements such as more advanced batteries and more energy-efficient
electronics, but also because of the higher density of cell sites to
accommodate increasing usage. The latter meant that the average distance
transmission from phone to the base station shortened, leading to increased
battery life whilst on the move.
Personal Handy-phone System mobiles and modems used in Japan
around 1997–2003
The second generation introduced a new variant of
communication called SMS or text messaging. It was initially available only on
GSM networks but spread eventually on all digital networks. The first
machine-generated SMS message was sent in the UK on 3 December 1992 followed in
1993 by the first person-to-person SMS sent in Finland. The advent of prepaid
services in the late 1990s soon made SMS the communication method of choice
amongst the young, a trend which spread across all ages.
2G also introduced the ability to access media content on
mobile phones. In 1998 the first downloadable content sold to mobile phones was
the ring tone, launched by Finland's Radiolinja (now Elisa). Advertising on the
mobile phone first appeared in Finland when a free daily SMS news headline
service was launched in 2000, sponsored by advertising.
Mobile payments were trialed in 1998 in Finland and Sweden
where a mobile phone was used to pay for a Coca Cola vending machine and car
parking. Commercial launches followed in 1999 in Norway. The first commercial
payment system to mimic banks and credit cards was launched in the Philippines
in 1999 simultaneously by mobile operators Globe and Smart.
The first full internet service on mobile phones was
introduced by NTT DoCoMo in Japan in 1999.
Mobile Broadband DATA
Mobile Broadband DATA
As the use of 2G phones became more widespread and people
began to utilize mobile phones in their daily lives, it became clear that
demand for data (such as access to browse the internet) was growing.
Furthermore, experience from fixed broadband services showed there would also
be an ever increasing demand for greater data speeds. The 2G technology was
nowhere near up to the job, so the industry began to work on the next
generation of technology known as 3G. The main technological difference that
distinguishes 3G technology from 2G technology is the use of packet switching
rather than circuit switching for data transmission.[30] In addition, the
standardization process focused on requirements more than technology (2 Mbit/s
maximum data rate indoors, 384 kbit/s outdoors, for example).
Inevitably this led to many competing standards with
different contenders pushing their own technologies, and the vision of a single
unified worldwide standard looked far from reality. The standard 2G CDMA
networks became 3G compliant with the adoption of Revision A to EV-DO, which
made several additions to the protocol while retaining backwards compatibility:
Introduction of several new forward link data rates that
increase the maximum burst rate from 2.45 Mbit/s to 3.1 Mbit/s
Protocols that would decrease connection establishment time
Ability for more than one mobile to share the same time slot
Introduction of QoS flags
All these were put in place to allow for low latency, low
bit rate communications such as VoIP.[31]
The first pre-commercial trial network with 3G was launched
by NTT DoCoMo in Japan in the Tokyo region in May 2001. NTT DoCoMo launched the
first commercial 3G network on 1 October 2001, using the WCDMA technology. In
2002 the first 3G networks on the rival CDMA2000 1xEV-DO technology were
launched by SK Telecom and KTF in South Korea, and Monet in the USA. Monet has
since gone bankrupt. By the end of 2002, the second WCDMA network was launched
in Japan by Vodafone KK (now Softbank). European launches of 3G were in Italy
and the UK by the Three/Hutchison group, on WCDMA. 2003 saw a further 8
commercial launches of 3G, six more on WCDMA and two more on the EV-DO
standard.
During the development of 3G systems, 2.5G systems such as
CDMA2000 1x and GPRS were developed as extensions to existing 2G networks.
These provide some of the features of 3G without fulfilling the promised high
data rates or full range of multimedia services. CDMA2000-1X delivers
theoretical maximum data speeds of up to 307 kbit/s. Just beyond these is the
EDGE system which in theory covers the requirements for 3G system, but is so
narrowly above these that any practical system would be sure to fall short.
The high connection speeds of 3G technology enabled a
transformation in the industry: for the first time, media streaming of radio
(and even television) content to 3G handsets became possible, with
companies such as RealNetworks and Disney among the early pioneers in
this type of offering.
In the mid-2000s (decade), an evolution of 3G technology
began to be implemented, namely High-Speed Downlink Packet Access (HSDPA). It
is an enhanced 3G (third generation) mobile telephony communications protocol
in the High-Speed Packet Access (HSPA) family, also coined 3.5G, 3G+ or turbo
3G, which allows networks based on Universal Mobile Telecommunications System
(UMTS) to have higher data transfer speeds and capacity. Current HSDPA
deployments support down-link speeds of 1.8, 3.6, 7.2 and 14.0 Mbit/s.
By the end of 2007, there were 295 million subscribers on 3G
networks worldwide, which reflected 9% of the total worldwide subscriber base.
About two thirds of these were on the WCDMA standard and one third on the EV-DO
standard. The 3G telecoms services generated over 120 Billion dollars of
revenues during 2007 and at many markets the majority of new phones activated
were 3G phones. In Japan and South Korea the market no longer supplies phones
of the second generation.
Although mobile phones had long had the ability to access
data networks such as the Internet, it was not until the widespread
availability of good quality 3G coverage in the mid-2000s (decade) that
specialized devices appeared to access the mobile internet. The first such
devices, known as "dongles", plugged directly into a computer through
the USB port. Another new class of device appeared subsequently, the so-called
"compact wireless router" such as the Novatel MiFi, which makes 3G
internet connectivity available to multiple computers simultaneously over
Wi-Fi, rather than just to a single computer via a USB plug-in.
Such devices became especially popular for use with laptop
computers due to the added portability they bestow. Consequently, some computer
manufacturers started to embed the mobile data function directly into the
laptop so a dongle or MiFi wasn't needed. Instead, the SIM card could be
inserted directly into the device itself to access the mobile data services.
Such 3G-capable laptops became commonly known as "netbooks". Other
types of data-aware devices followed in the netbook's footsteps. By the
beginning of 2010, E-readers, such as the Amazon Kindle and the Nook from
Barnes & Noble, had already become available with embedded wireless
internet, and Apple Computer had announced plans for embedded wireless internet
on its iPad tablet devices beginning that Fall.
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