Cellular Phone

WHAT IS CELLULAR PHONE?

A mobile or cellular telephone is a long-range, portable electronic device for personal telecommunications over long distances.

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). Cellular networks were first introduced in the early to mid 1980s (the 1G generations). Prior mobile phones operating without a cellular network (the so-called 0G generation), such as Mobile Telephone Service, date back to 1945. Until the mid to late 1980s, most mobile phones were sufficiently large that they were permanently installed in vehicles as car phones. With the advance of miniaturization, currently the vast majority of mobile phones are handheld. In addition to the standard voice function of a telephone, a mobile phone 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.

The world's largest mobile phone operators (based on customer totals) include China Mobile, Vodafone, and China Unicom. The world's largest mobile phone manufacturers include Audiovox, BenQ-Siemens, High Tech Computer Corporation, Fujitsu, Kyocera, LG, Motorola, NEC,[i-mate], Nokia, Panasonic (Matsushita Electric), Pantech Curitel, Philips, Sagem, Samsung, Sanyo, Sharp, Siemens SK Teletech, Sony Ericsson, T&A Alcatel, T-Mobile, and Toshiba.

There is also specialist communication systems related to, but distinct from mobile phones, such as Professional Mobile Radio. Mobile phones are also distinct from cordless telephones, which generally operate only within a limited range of a specific base station. Technically, the term mobile phone includes such devices as satellite phones and pre-cellular mobile phones such as those operating via MTS which do not have a cellular network, whereas the related term cell (ular) phone does not. In practice, the two terms are used nearly interchangeably, with the preferred term varying by location. There are lots of different networks on mobile phones. Some are pay as you go, where you can buy top ups and add them to your phone, so there is no monthly bill, and some are pay monthly. This means you get a bill every month for how much calls and texts you make.

Luxembourg has the highest mobile phone penetration rate in the world, at 164% in December 2005. The total number of mobile phone subscribers in the world was estimated at 2.14 billion in 2005. Around 80% of world's population has mobile phone coverage as of 2006. This figure is expected to increase to 90% by the year 2010.

At present, Africa has the largest growth rate of cellular subscribers in the world. African markets are expanding nearly twice as fast as Asian markets. The availability of Prepaid or pay as you go services, where the subscriber does not have to commit to a long term contract, has helped fuel this growth on a monumental scale, not only in Africa but on other continents as well.

All European nations and most Asian and African nations have adopted GSM. In other countries, such as the United States, Australia, Japan, and South Korea, legislation does not require any particular standard, and GSM coexists with other standards, such as CDMA and iDEN.

Source: WIKIPEDIA the free encyclopedia.