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A mobile phone or '''cell(ular) phone''' is an electronic Telecommunications device. Most current mobile phones connect to a Cellular Network of Base Station s ( Cell Site s), which is in turn interconnected to the public switched telephone network (PSTN)(the exception are Satellite Phone s). Cellular networks were first introduced in the early to mid 1980s (the 1G generation). Prior mobile phones operating without a cellular network (the so-called 0G generation), such as Mobile Telephone Service , date back to 1946. Until the mid to late 1980s, most mobile phones were sufficiently large that they were often permanently installed in vehicles as Car Phone s. 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, Packet Switching for access to the Internet , and MMS for sending and receiving photos and video. Some of the world's largest mobile phone manufacturers include Alcatel , Audiovox , BenQ-Siemens , Dopod , Fujitsu , Kyocera , LG , Motorola , NEC , Nokia , Panasonic (Matsushita Electric), Philips , Sagem , Samsung , Sanyo , Sharp , SK Teletech , Sony Ericsson , and Toshiba . There are also specialist communication systems related to, but distinct from mobile phones, such as Professional Mobile Radio . Mobile phones are also distinct from Cordless Telephone s, which generally operate only within a limited range of a specific base station. Technically, the term ''mobile phone'' includes such devices as Satellite Phone s 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. WORLDWIDE DEPLOYMENT Radio phones have a Long And Varied History that stretches back to the 1950s, with hand-held cellular radio devices being 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 most of Europe , wealthier parts of Asia , Africa, the Caribbean , Latin America , Australia , Canada , and the United States , mobile phones are now widely used, with the majority of the adult, teenage, and even child population owning one. At present India and China have the largest growth rates of cellular subscribers in the world. 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. The mobile phone has become ubiquitous because of the interoperability of mobile phones across different networks and countries. This is due to the equipment manufacturers working to meet one of a few standards, particularly the GSM standard which was designed for Europe-wide interoperability. All European nations and most Asian and African nations adopted it as their sole standard. In other countries, such as the United States , Japan , and South Korea , legislation does not require any particular standard, and GSM coexists with other standards, such as CDMA and iDen MOBILE PHONE CULTURE OR CUSTOMS In less than twenty years, mobile phones have gone from being rare and expensive pieces of equipment used by businesses to a pervasive low-cost personal item. In many countries, mobile phones now outnumber land-line telephones, with most adults and many children now owning mobile phones. It is not uncommon for young adults to simply own a mobile phone instead of a land-line for their residence. In some developing countries, where there is little existing fixed-line infrastructure, the mobile phone has become widespread. With high levels of mobile telephone penetration, a mobile culture has evolved, where the phone becomes a key social tool, and people rely on their mobile phone addressbook to keep in touch with their friends. Many people keep in touch using SMS , and a whole culture of " Texting " has developed from this. The commercial market in SMS's is growing. Many phones even offer Instant Messenger services to increase the simplicity and ease of texting on phones. Cellular phones in Japan , offering Internet capabilities such as NTT DoCoMo 's I-mode , offer text messaging via standard e-mail. The mobile phone itself has also become a Totem ic and Fashion object, with users decorating, customizing, and accessorizing their mobile phones to reflect their personality. This has emerged as its own industry. The sale of commercial Ringtones exceeded $2.5 billion in 2004 {Link without Title} . Mobile phone etiquette has become an important issue with mobiles ringing at funerals, weddings, movies, and plays. Users often speak at increased volume which has led to places like bookshops, libraries, movie theatres, doctor's offices, and houses of worship posting signs prohibiting the use of mobile phones, sometimes even installing illegal jamming equipment to prevent them. Many rail companies, particularly those providing long-distance services, offer a "quiet car" where phone use is prohibited, much like the designated non-smoking cars in the past. Mobile Phone Use On Aircraft is also prohibited, but because of concerns of possible interference with aircraft radio communications {Link without Title} . Cameraphones and videophones that can capture video and take photographs are increasingly being used to cover breaking news. Stories like the London Bombings , the Indian Ocean Tsunami and Hurricane Katrina have been reported on by cameraphone users on news sites like NowPublic and photosharing sites like Flickr . In Japan, cellular phone companies provide immediate notification of Earthquakes and other natural disasters to their customers free of charge. In the event of an emergency, disaster response crews can locate trapped or injured people using the signals from their mobile phones; an interactive menu accessible through the phone's Internet browser notifies the company if the user is safe or in distress. MOBILE PHONE FEATURES See Also: Mobile phone features Mobile phones often have features beyond sending text messages and make voice calls—including Internet browsing, music (MP3) playback, personal organizers, E-mail , built-in cameras and camcorders, Ringtones , games, radio, Push-to-Talk (PTT), infrared and bluetooth connectivity, call registers, and ability to watch streaming video or download video for later viewing. TECHNOLOGY Mobile phones and the network they operate under vary significantly from provider to provider, and even from nation to nation. However, all of them communicate through electromagnetic Radio Wave s with a cell site base station, the antennas of which are usually mounted on a tower, pole, or building. The phones have a low-power Transceiver that transmits voice and data to the nearest cell sites, usually .5 to 8 miles away. When the cellular phone or data device is turned on, it registers with the Mobile Telephone Exchange , or switch, with its unique identifiers, and will then be alerted by the mobile switch when there is an incoming telephone call. The handset constantly listens for the strongest signal being received from the surrounding base stations. As the user moves around the network, the mobile device will " Handoff " to new cell sites. Cell sites have relatively low-power (often only one or two Watts) radio transmitters which broadcast their presence and relay communications between the mobile handsets and the switch. The switch in turn connects the call to another subscriber of the same Wireless Service Provider or to the Public Telephone Network , which includes the networks of other wireless carriers. The dialogue between the handset and the cell site is a stream of digital data that includes digitized audio (except for the first generation analog networks). The technology that achieves this depends on the system which the Mobile Phone Operator has adopted. Some technologies include AMPS for analog, and TDMA , CDMA , GSM , GPRS , EV-DO , and UMTS for digital communications. Each network operator has a unique Radio Frequency band. CONTROVERSY Health controversy See Also: Mobile phone radiation and health As with many new technologies, concerns have arisen about the effects on Health from using a mobile telephone. There is a small amount of scientific evidence for an increase in certain types of rare Tumors ( Cancer ) in long-time, heavy users. More recently a pan- European study provided significant evidence of Genetic damage under certain conditions. Some researchers also report the mobile phone industry has interfered with further research on health risks. So far, however, the World Health Organization Task Force on EMF effects on health has no definitive conclusion on the veracity of these allegations. (See also Electromagnetic Radiation Hazard .) It is generally thought, however, that RF is incapable of producing any more than heating effects, as it is considered Non-ionizing Radiation ; in other words, it lacks the energy to disrupt molecular bonds such as occurs in Genetic Mutation s. Long-term mobile phone use raises brain tumor risk: study , Reuters, 31 March 2006 Driving controversy See Also: Mobile phones and driving safety Another controversial but more lethal health concern is the correlation with Road Traffic Accident s. Several studies have shown that motorists have a much higher risk of collisions and losing control of the vehicle while talking on the mobile telephone simultaneously with driving, even when using " Hands-free " systems. A study in ''The New England Journal of Medicine'' reports that drivers who used mobile phones while driving were four times more likely to crash than those who don't, a rate equal to that for drunken driving at the .01 blood alcohol concentration (BAC) level. An experiment conducted by the American television show '' MythBusters '' concluded that use of mobile phones while driving poses the same risk as someone operating a vehicle while Under The Influence of alcohol. Accidents involving a driver being distracted by talking on a mobile phone have begun to be prosecuted as negligence similar to driving while intoxicated. At least 25 countries restrict or prohibit cell and other wireless technology: India , Israel , Japan , Portugal and Singapore all prohibit mobile phone use while driving. Australia , Brazil , Chile , Croatia , Denmark , Germany , Greece , Hungary , Iran , Italy , the Netherlands , Poland , the Philippines , Romania , Slovenia , South Africa , Spain , Switzerland , Turkey , the United Kingdom , and the United Arab Emirates prohibit the use of hand-held cell phones while driving. Drivers in the Czech Republic and France may use cell phones but can be fined if they are involved in crashes while using such a device. Restrictive legislation has been proposed in 40 states in the US, but only New York State, Connecticut, and New Jersey , and Washington, D.C. have passed laws regarding cell phone use and driving. Security concerns Early mobile phones did not have much security designed in. Some problems with these models were "cloning", a variant of Identity Theft , and "scanning" whereby third parties in the local area could intercept and eavesdrop in on calls. Analogue phones could also be listened to on some radio scanners. Although more recent digital systems (such as GSM ) have attempted to address these fundamental issues, security problems continue to persist. Vulnerabilities (such as SMS Spoofing ) have been found in many current protocols that continue to allow the possibility of eavesdropping or cloning. Terrorism The Madrid Bombings were set off by mobile devices in 2004. During the 7/7/05 Bombing in London the mobile network was disabled by the authorities who tried to pre-empt the use of this type of threat. FUTURE PROSPECTS ]] There is a great deal of active research and development into mobile phone technology that is currently underway. Some of the improvements that are being worked on are:
TERMINOLOGY Mobile phone terms ; Brick : 1. A large, heavy, and usually obsolete wireless mobile phone, such as the Motorola International 3200 . (also ''Cinderblock'') : 2. A mobile phone of a solid form factor. Originally many Nokia models were of this design. ; Clamshell : A mobile phone of a form factor resembling the shell of a clam, with the ability to open up in the same way. ; Cell phone, cellular phone, or cell : Term used currently in the United States and Canada (and in other countries as well during the 1980s ) to refer to most mobile phones. It technically applies specifically to mobile phones which use a Cellular Network . In developing mobile phone technology, American electrical engineers saw the main technical problem as achieving a smooth handoff from one radio antenna to the next. After they gave the name "cell" to the zone covered by each antenna, it was a natural choice for them to apply the term "cellular" to both the technology and the phones that ran on it. ; Handset : A term used by manufacturers to refer to a mobile phone. Also commonly used by industry insiders. ; Hands-free car kit: Mobile phone accessory used to talk while keeping hands on the steering wheel. ; Mobile phone : A term covering cellular phones, satellite phones, and any phones giving wide-ranging mobility, used in most English-speaking countries. In some English-speaking countries such as the UK and Australia, common usage refers specifically to cellular phones. ; Ringtone : A song or tune that is played when a mobile phone is receiving a call. ; Satellite Phone : A mobile phone which communicates with a satellite rather than a land-based network. ; 3G phone : A mobile phone which uses a 3G network, with greater bandwidth allowing faster data downloads and face-to-face video calling. ; Wireless phone : A term that generally refers to a Wi-Fi VoIP phone but is sometimes used by the mobile phone industry to describe mobile phones. Related systems which are not cell phones ; Cordless Phone (portable phone) : Cordless phones are standard telephones with radio handsets. Unlike mobile phones, cordless phones use private base stations that are not shared between subscribers. The base station is connected to a land-line. ; , the international digital PMR standard, to implement public mobile networks, but normally PMR systems are sufficiently separate from the phone network to not really be considered phones but rather radios. ; Radio phone : This is a term which covers radios which could connect into the telephone network. These phones may not be mobile; for example, they may require a Mains power supply. Also, they may require the assistance of a human operator to set up a PSTN phone call. Terms in other countries SEE ALSO
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