The history focuses on
communication devices which connect wirelessly to the public switched
telephone network. Thetransmission of speech by radio has
a long and varied history going back to Reginald Fessenden's
invention and shore-to-ship demonstration of radio telephony. The first mobile
telephones were barely portable compared to today's compact hand-held devices.
Along with the process of developing more portable technology, drastic changes
have taken place in the networking of wireless communication and the prevalence
of its use.
Handheld mobile phone
Prior to 1973, mobile telephony was
limited to phones installed in cars and other vehicles. Motorola was the first company to produce a handheld mobile phone. On 3
April 1973 when Martin Cooper,
a Motorola researcher and
executive, made the first mobile telephone call from handheld subscriber
equipment, placing a call to Dr. Joel S. Engel of Bell Labs. The prototype handheld phone used by Dr.
Cooper weighed 1.1 kg and measured 23 cm long, 13 cm deep and 4.45 cm wide. The prototype offered a talk time of just 30 minutes and took 10
hours to re-charge.
John F. Mitchell, Motorola's chief of portable communication products and Cooper's boss in
1973, played a key role in advancing the development of handheld mobile
telephone equipment. Mitchell successfully pushed Motorola to develop wireless communication products
that would be small enough to use anywhere and participated in the design of
the cellular phone.
Digital cellular networks – 2G
Two 1991 GSM mobile
phones with several AC adapters
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-band 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 PCMCIA1.8 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 gramhand-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 – 3G
Main article: 3G
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. 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.
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 EDGEsystem
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. Further speed increases are available with HSPA+, which provides speeds of up to 42 Mbit/s downlink and
84 Mbit/s with Release 9 of the 3GPP standards.
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.
Native IP networks – 4G
Main article: 4G
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 Telia Sonera.
One of the main ways in which 4G differed
technologically from 3G was in its elimination of circuit switching, instead employing an all-IP network. Thus,
4G ushered in a treatment of voice calls just like any other type of streaming
audio media, utilizing packet switching over internet, LAN or WAN networks via VoIP.
Earth-orbiting satellites can cover remote
areas out of reach of wired networks or where construction of a cellular
network is uneconomic. The Inmarsat satellite telephone system, originally
developed in 1979 for safety of life at sea, is now also useful for areas out
of reach of landline, conventional cellular, or marine VHF radio stations. In
1998 the Iridium satellite system was set up, and although the initial operating company
went bankrupt due to high initial expenses, the service is available today.
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