Mobile phone
A mobile telephone or cellular telephone (commonly, "mobile phone" or "cell phone") is a long-range, portable electronic device used for mobile communication. In addition to the standard voice function of a telephone, current mobile phones can support many additional services such as SMS for text messaging, email, packet switching for access to the Internet, and MMS for sending and receiving photos and video. Most current mobile phones connect to a cellular network of base stations (cell sites), which is in turn interconnected to the public switched telephone network (PSTN) (the exception are satellite phones).
History
Main article: History of mobile phones
Various cell phones from the past 10-15 years:
Legend:
1. NEC Cellstar 500 series
2. Nokia 2110 series (1994)
3. Nokia 5120 (1998)
4. Kyocera 2135 (2002)
5. Audiovox CDM8300
6. Samsung SCH-A650 (2004)
The introduction of cells for mobile phone base stations, invented in 1947 by Bell Labs engineers at AT&T, was further developed by Bell Labs during the 1960s. Radiophones have a long and varied history going back to the Second World War with military use of radio telephony links and civil services in the 1950s, while hand-held cellular radio devices have been available since 1983. Due to their low establishment costs and rapid deployment, mobile phone networks have since spread rapidly throughout the world, outstripping the growth of fixed telephony.
In 1945, the zero generation (0G) of mobile telephones was introduced. 0G mobile telephones, such as Mobile Telephone Service, were not officially categorized as mobile phones, since they did not support the automatic change of channel frequency during calls, which allows the user to move from one cell (the base station coverage area) to another cell, a feature called "handover".
In 1970, Bell Labs invented such a "call handoff" feature, which allowed mobile-phone users to travel through several cells during the same conversation. Motorola is widely considered to be the inventor of the first practical mobile phone for handheld use in a non-vehicle setting. Using a modern, if somewhat heavy portable handset, they made the first call on a handheld mobile phone in April, 1973.
The first commercial cellular network was launched in Japan by NTT in 1979. Fully automatic cellular networks were first introduced in the early to mid 1980s (the 1G generation) with the Nordic Mobile Telephone (NMT) system in 1981. This was followed by a boom in mobile telephone usage, particularly in Northern Europe.
The first "modern" network technology on digital 2G (second generation) cellular technology was launched by Radiolinja (now part of Elisa Group) in 1991 in Finland on the GSM standard which also marked the introduction of competition in mobile telecoms when Radiolinja challenged incumbent Telecom Finland (now part of TeliaSonera) who ran a 1G NMT network. A decade later, the first commercial launch of 3G (Third Generation) was again in Japan by NTT DoCoMo on the WCDMA standard. However, Martin Cooper, a Motorola engineer, is credited with the invention of the modern mobile phone in the 1990s. Until the early 1990s, most mobile phones were too large to be carried in a jacket pocket, so they were typically installed in vehicles as car phones. With the miniaturization of digital components, mobile phones have become increasingly handy over the years.
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Manufacturers
Nokia Corporation is currently the world's largest manufacturer of mobile telephones, with a global device market share of approximately 36% in Q1 of 2007.[1] Other mobile phone manufacturers include Apple Inc., Audiovox (now UT Starcom), Benefon, BenQ-Siemens, High Tech Computer Corporation (HTC), Fujitsu, Kyocera, LG Mobile, Mitsubishi, Motorola, NEC, Neonode, Panasonic (Matsushita Electric), Pantech Curitel, Philips, Research In Motion, Sagem, Samsung, Sanyo, Sharp, Siemens, Sierra Wireless, SK Teletech, Sonim Technologies, Sony Ericsson, T&A Alcatel,Toshiba, and Verizon. There are also specialist communication systems related to (but distinct from) mobile phones, such as Professional Mobile Radio.
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Subscriptions
This Railfone found on some Amtrak trains uses cellular technology.
See also: List of mobile network operators
Several countries, including the UK, now have more mobile phones than people.[2] There are over five hundred million active mobile phone accounts in China, as of 2007.[3] Luxembourg has the highest mobile phone penetration rate in the world, at 164% in December 2001. In Hong Kong the penetration rate reached 117% of the population in September 2004.[4] The total number of mobile phone subscribers in the world was estimated at 2.14 billion in 2005.[5] The subscriber count reached 2.7 billion by end of 2006 according to Informa. Around 80% of the world's population enjoys mobile phone coverage as of 2006. This figure is expected to increase to 90% by the year 2010.[6]
At present, Africa has the largest growth rate of cellular subscribers in the world[7], its markets expanding nearly twice as fast as Asian markets.[8] The availability of prepaid or 'pay as you go' services, where the subscriber is not committed to a long term contract, has helped fuel this growth to a monumental scale in Africa as well as in other continents.
On a numerical basis, India is the largest growth market, adding about 6 million cell phones every month. [9] With 156.31 million cell phones, market penetration in the country is still low at 17.45% India expects to reach 500 million subscribers by end of 2010.
All European countries and most Asian and African ones have adopted the GSM system. In other countries, such as the United States, Australia, Brazil, India, Japan, and South Korea, legislation does not require any particular standard, with the result that GSM co-exists with other standards such as CDMA and iDEN.
While some systems of payment are 'pay as you go' where conversation time is purchased and added to a phone unit via an Internet account or in shops or ATMs, other systems are more traditional ones where bills are paid by regular intervals.
