A mobile phone (also called cellphone or handphone,[1] including wireless phone, cell phone, cellular phone, cellular telephone or cell telephone) is a long-range, electronic device used for mobile voice or data communication over a network of specialized base stations known as cell sites. In addition to the standard voice function of a mobile phone, telephone, current mobile phones may support many additional services, and accessories, such as SMS for text messaging, email, packet switching for access to the Internet, gaming, Bluetooth, infrared, camera with video recorder and MMS for sending and receiving photos and video, MP3 player, radio and GPS. 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 is satellite phones).
In 2008 there were 4,100 million mobile cellular subscriptions in the world.[2] A mobile phone proper typically has a telephone keypad, more advanced devices have a separate key for each letter. Some mobile phones have a touchscreen.
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History
In 1908, U.S. Patent 887,357 for a wireless telephone was issued in to Nathan B. Stubblefield of Murray, Kentucky. He applied this patent to "cave radio" telephones and not directly to cellular telephony as the term is currently understood.[3] Cells for mobile phone base stations were invented in 1947 by Bell Labs engineers at AT&T and further developed by Bell Labs during the 1960s. Radiophones have a long and varied history going back to Reginald Fessenden's invention and shore-to-ship demonstration of radio telephony, through 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 1973. A patent for the first wireless phone as we know today was issued in US Patent Number 3,449,750 to George Sweigert of Euclid, Ohio on June 10, 1969.
In 1945, the zero generation (0G) of mobile telephones was introduced. 0G mobile phones, such as Mobile Telephone Service, were not cellular, and so did not feature "handover" from one base station to the next and reuse of radio frequency channels.[citation needed] Like other technologies of the time, it involved a single, powerful base station covering a wide area, and each telephone would effectively monopolize a channel over that whole area while in use. The concepts of frequency reuse and handoff as well as a number of other concepts that formed the basis of modern cell phone technology are first described in U.S. Patent 4,152,647, issued May 1, 1979 to Charles A. Gladden and Martin H. Parelman, both of Las Vegas, Nevada and assigned by them to the United States Government.
This is the first embodiment of all the concepts that formed the basis of the next major step in mobile telephony, the Analog cellular telephone. Concepts covered in this patent (cited in at least 34 other patents) also were later extended to several satellite communication systems. Later updating of the cellular system to a digital system credits this patent.
Martin Cooper, a Motorola researcher and executive is widely considered to be the inventor of the first practical mobile phone for handheld use in a non-vehicle setting. Cooper is the inventor named on "Radio telephone system" filed on October 17, 1973 with the US Patent Office and later issued as US Patent 3,906,166.[4] Using a modern, if somewhat heavy portable handset, Cooper made the first call on a handheld mobile phone on April 3, 1973 to a rival, Dr. Joel S. Engel of Bell Labs.[5]
The first commercial citywide 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). The Nordic Mobile Telephone (NMT) system went online in Denmark, Finland, Norway and Sweden in 1981.[6]
In 1983, Motorola DynaTAC was the first approved mobile phone by FCC in the United States. In 1984, Bell Labs developed modern commercial cellular technology (based, to a large extent, on the Gladden, Parelman Patent), which employed multiple, centrally controlled base stations (cell sites), each providing service to a small area (a cell). The cell sites would be set up such that cells partially overlapped. In a cellular system, a signal between a base station (cell site) and a terminal (phone) only need be strong enough to reach between the two, so the same channel can be used simultaneously for separate conversations in different cells.
Cellular systems required several leaps of technology, including handover, which allowed a conversation to continue as a mobile phone traveled from cell to cell. This system included variable transmission power in both the base stations and the telephones (controlled by the base stations), which allowed range and cell size to vary. As the system expanded and neared capacity, the ability to reduce transmission power allowed new cells to be added, resulting in more, smaller cells and thus more capacity. The evidence of this growth can still be seen in the many older, tall cell site towers with no antennae on the upper parts of their towers. These sites originally created large cells, and so had their antennae mounted atop high towers; the towers were designed so that as the system expanded—and cell sizes shrank—the antennae could be lowered on their original masts to reduce range.
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.
The first data services appeared on mobile phones starting with person-to-person SMS text messaging in Finland in 1993. First trial payments using a mobile phone to pay for a Coca Cola vending machine were set in Finland in 1998. The first commercial payments were mobile parking trialled in Sweden but first commercially launched in Norway in 1999. The first commercial payment system to mimick banks and credit cards was launched in the Philippines in 1999 simultaneously by mobile operators Globe and Smart. The first content sold to mobile phones was the ringing tone, first launched in 1998 in Finland. The first full internet service on mobile phones was i-Mode introduced by NTT DoCoMo in Japan in 1999.
In 2001 the first commercial launch of 3G (Third Generation) was again in Japan by NTT DoCoMo on the WCDMA standard.[7]
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 and the development of more sophisticated batteries, mobile phones have become smaller and lighter.
Handsets
There are several categories of mobile phones, from basic phones to feature phones such as musicphones and cameraphones, to smartphones. The first smartphone was the Nokia 9000 Communicator in 1996 which incorporated PDA functionality to the basic mobile phone at the time. As miniaturisation and increased processing power of microchips has enabled ever more features to be added to phones, the concept of the smartphone has evolved, and what was a high-end smartphone five years ago, is a standard phone today. Several phone series have been introduced to address a given market segment, such as the RIM BlackBerry focusing on enterprise/corporate customer email needs; the SonyEricsson Walkman series of musicphones and Cybershot series of cameraphones; the Nokia N-Series of multimedia phones; and the Apple iPhone which provides full-featured web access and multimedia capabilities.
Features
Mobile phones often have features beyond sending text messages and making voice calls, including call registers, GPS navigation, music (MP3) and video (MP4) playback, RDS radio receiver, alarms, memo and document recording, personal organiser and personal digital assistant functions, ability to watch streaming video or download video for later viewing, video calling, built-in cameras (3.2+ Mpx) and camcorders (video recording), with autofocus and flash, ringtones, games, PTT, memory card reader (SD), USB (2.0), infrared, Bluetooth (2.0) and WiFi connectivity, instant messaging, Internet e-mail and browsing and serving as a wireless modem for a PC, and soon will also serve as a console of sorts to online games and other high quality games.
Some phones includes touchscreen.
The total value of mobile data services exceeds the value of paid services on the Internet, and was worth 31 billion dollars in 2006 (source Informa).[citation needed] The largest categories of mobile services are music, picture downloads, videogaming, adult entertainment, gambling, video/TV.
Nokia and the University of Cambridge are showing off a bendable cell phone called Morph.[8]
Applications
The most commonly used data application on mobile phones is SMS text messaging, with 74% of all mobile phone users as active users (over 2.4 billion out of 3.3 billion total subscribers at the end of 2007). SMS text messaging was worth over 100 billion dollars in annual revenues in 2007 and the worldwide average of messaging use is 2.6 SMS sent per day per person across the whole mobile phone subscriber base. (source Informa 2007). The first SMS text message was sent from a computer to a mobile phone in 1992 in the UK, while the first person-to-person SMS from phone to phone was sent in Finland in 1993.
The other non-SMS data services used by mobile phones were worth 31 Billion dollars in 2007, and were led by mobile music, downloadable logos and pictures, gaming, gambling, adult entertainment and advertising (source: Informa 2007). The first downloadable mobile content was sold to a mobile phone in Finland in 1998, when Radiolinja (now Elisa) introduced the downloadable ringing tone service. In 1999 Japanese mobile operator NTT DoCoMo introduced its mobile internet service, i-Mode, which today is the world's largest mobile internet service and roughly the same size as Google in annual revenues.
The first mobile news service, delivered via SMS, was launched in Finland in 2000. Mobile news services are expanding with many organisations providing "on-demand" news services by SMS. Some also provide "instant" news pushed out by SMS. Mobile telephony also facilitates activism and public journalism being explored by Reuters and Yahoo![9] and small independent news companies such as Jasmine News in Sri Lanka.
Companies like Monster.com are starting to offer mobile services such as job search and career advice. Consumer applications are on the rise and include everything from information guides on local activities and events to mobile coupons and discount offers one can use to save money on purchases. Even tools for creating websites for mobile phones are increasingly becoming available.
Mobile payments were first trialled in Finland in 1998 when two Coca-Cola vending machines in Espoo were enabled to work with SMS payments. Eventually the idea spread and in 1999 the Philippines launched the first commercial mobile payments systems, on the mobile operators Globe and Smart. Today mobile payments ranging from mobile banking to mobile credit cards to mobile commerce are very widely used in Asia and Africa, and in selected European markets. For example in the Philippines it is not unusual to have one's entire paycheck paid to the mobile account. In Kenya the limit of money transfers from one mobile banking account to another is one million US dollars. In India paying utility bills with mobile gains a 5% discount. In Estonia the government found criminals collecting cash parking fees, so the government declared that only mobile payments via SMS were valid for parking and today all parking fees in Estonia are handled via mobile and the crime involved in the activity has vanished.
Mobile Applications are developed using the Six M's (previously Five M's) service-development theory created by the author Tomi Ahonen with Joe Barrett of Nokia and Paul Golding of Motorola. The Six M's are Movement (location), Moment (time), Me (personalization), Multi-user (community), Money (payments) and Machines (automation). The Six M's / Five M's theory is widely referenced in the telecoms applications literature and used by most major industry players. The first book to discuss the theory was Services for UMTS by Ahonen & Barrett in 2002.
Power supply
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Mobile phones generally obtain power from batteries, which can be recharged from a USB port, from portable batteries, from mains power or a cigarette lighter socket in a car using an adapter (often called battery charger or wall wart) or from a solar panel or a dynamo (that can also use a USB port to plug the phone).
On 17 February 2009, the GSM Association announced[10] that they had agreed on a standard charger for mobile phones. The standard connector to be adopted by 17 manufacturers including Nokia, Motorola and Samsung is to be the micro-USB connector (several media reports erroneously reported this as the mini-USB). The new chargers will be much more efficient than existing chargers. Having a standard charger for all phones, means that manufacturers will no longer have to supply a charger with every new phone.
Formerly, the most common form of mobile phone batteries were nickel metal-hydride, as they have a low size and weight. Lithium-Ion batteries are sometimes used, as they are lighter and do not have the voltage depression that nickel metal-hydride batteries do. Many mobile phone manufacturers have now switched to using lithium-Polymer batteries as opposed to the older Lithium-Ion, the main advantages of this being even lower weight and the possibility to make the battery a shape other than strict cuboid. Mobile phone manufacturers have been experimenting with alternative power sources, including solar cells.
SIM card
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In addition to the battery, GSM mobile phones require a small microchip, called a Subscriber Identity Module or SIM Card, to function. Approximately the size of a small postage stamp, the SIM Card is usually placed underneath the battery in the rear of the unit, and (when properly activated) stores the phone's configuration data, and information about the phone itself, such as which calling plan the subscriber is using. When the subscriber removes the SIM Card, it can be re-inserted into another phone and used as normal.
Each SIM Card is activated by use of a unique numerical identifier; once activated, the identifier is locked down and the card is permanently locked in to the activating network. For this reason, most retailers refuse to accept the return of an activated SIM Card.
Those cell phones that do not use a SIM Card have the data programmed in to their memory. This data is accessed by using a special digit sequence to access the "NAM" as in "Name" or number programming menu. From here, one can add information such as a new number for your phone, new Service Provider numbers, new emergency numbers, change their Authentication Key or A-Key code, and update their Preferred Roaming List or PRL. However, to prevent someone from accidentally disabling their phone or removing it from the network, the Service Provider puts a lock on this data called a Master Subsidiary Lock or MSL.
The MSL also ensures that the Service Provider gets payment for the phone that was purchased or "leased". For example, the Motorola RAZR V9C costs upwards of CAD $500. You can get one for approximately $200, depending on the carrier. The difference is paid by the customer in the form of a monthly bill. If the carrier did not use a MSL, then they may lose the $300–$400 difference that is paid in the monthly bill, since some customers would cancel their service and take the phone to another carrier.
The MSL applies to the SIM only so once the contract has been completed the MSL still applies to the SIM. The phone however, is also initially locked by the manufacturer into the Service Providers MSL. This lock may be disabled so that the phone can use other Service Providers SIM cards. Most phones purchased outside the US are unlocked phones because there are numerous Service Providers in close proximity to one another or have overlapping coverage. The cost to unlock a phone varies but is usually very cheap and is sometimes provided by independent phone vendors.
Having an unlocked phone is extremely useful for travelers due to the high cost of using the MSL Service Providers access when outside the normal coverage areas. It can cost sometimes up to 10 times as much to use a locked phone overseas as in the normal service area, even with discounted rates. T-Mobile will provide a SIM unlock code to account holders in good standing after 90 days according to their FAQ.
For example, in Jamaica, an AT&T subscriber might pay in excess of US$1.65 per minute for discounted international service while a B-Mobile (Jamaican) customer would pay US$0.20 per minute for the same international service. Some Service Providers focus sales on international sales while others focus on regional sales. For example, the same B-Mobile customer might pay more for local calls but less for international calls than a subscriber to the Jamaican national phone C&W (Cable & Wireless) company. These rate differences are mainly due to currency variations because SIM purchases are made in the local currency. In the US, this type of service competition does not exist because some of the major Service Providers do not offer Pay-As-You-Go services. [Needs Pay-As-You-Go references, rumored T-Mobile,Verizon provide one, AT&T does not as of 12/2008]
Market
In Q3/2008, Nokia was the world's largest manufacturer of mobile phones, with a global device market share of 39.4%, followed by Samsung (17.3%), Sony Ericsson (8.6%), Motorola (8.5%) and LG Electronics (7.7%). These manufacturers accounted for over 80% of all mobile phones sold at that time.[11]
Other manufacturers include Apple Inc., Audiovox (now UTStarcom), Benefon, BenQ-Siemens, CECT, High Tech Computer Corporation (HTC), Fujitsu, Kyocera, Mitsubishi Electric, NEC, Neonode, Panasonic, Palm, Matsushita, Pantech Wireless Inc., Philips, Qualcomm Inc., Research in Motion Ltd. (RIM), Sagem, Sanyo, Sharp, Siemens, Sendo, Sierra Wireless, SK Teletech, T&A Alcatel, Huawei, Trium and Toshiba.[citation needed] There are also specialist communication systems related to (but distinct from) mobile phones.
Media
The mobile phone became a mass media channel in 1998 when the first ringing tones were sold to mobile phones by Radiolinja in Finland. Soon other media content appeared such as news, videogames, jokes, horoscopes, TV content and advertising. In 2006 the total value of mobile phone paid media content exceeded internet paid media content and was worth 31 Billion dollars (source Informa 2007). The value of music on phones was worth 9.3 Billion dollars in 2007 and gaming was worth over 5 billion dollars in 2007 (source Netsize Guide 2008 [12]).
The mobile phone is often called the Fourth Screen (if counting cinema, TV and PC screens as the first three) or Third Screen (counting only TV and PC screens). It is also called the Seventh of the Mass Media (with Print, Recordings, Cinema, Radio, TV and Internet the first six). Most early content for mobile tended to be copies of legacy media, such as the banner advertisement or the TV news highlight video clip. Recently unique content for mobile has been emerging, from the ringing tones and ringback tones in music to "mobisodes," video content that has been produced exclusively for mobile phones.
The advent of media on the mobile phone has also produced the opportunity to identify and track Alpha Users or Hubs, the most influential members of any social community. AMF Ventures measured in 2007 the relative accuracy of three mass media, and found that audience measures on mobile were nine times more accurate than on the internet and 90 times more accurate than on TV.
Terminology
Related non-mobile-phone systems
- Car phone
- A type of telephone permanently mounted in a vehicle, these often have more powerful transmitters, an external antenna and loudspeaker for handsfree use. They usually connect to the same networks as regular mobile phones.
- Cordless telephone (portable phone)
- Cordless phones are telephones which use one or more radio handsets in place of a wired handset. The handsets connect wirelessly to a base station, which in turn connects to a conventional land line for calling. Unlike mobile phones, cordless phones use private base stations (belonging to the land-line subscriber), and which are not shared.
- Professional Mobile Radio
- Advanced professional mobile radio systems can be very similar to mobile phone systems. Notably, the IDEN standard has been used as both a private trunked radio system as well as the technology for several large public providers. Similar attempts have even been made to use TETRA, the European digital PMR standard, to implement public mobile networks.
- 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, they may require the assistance of a human operator to set up a PSTN phone call.
- Satellite phone
- This type of phone communicates directly with an artificial satellite, which in turn relays calls to a base station or another satellite phone. A single satellite can provide coverage to a much greater area than terrestrial base stations. Since satellite phones are costly, their use is typically limited to people in remote areas where no mobile phone coverage exists, such as mountain climbers, mariners in the open sea, and news reporters at disaster sites.
Usage
A Mobile phone novel or cell phone novels are the first literary genre to emerge from the cellular age via text messaging to a website that collects the novels as a whole. [13] In virtual online computer games, readers can put themselves into first person in the story. Cell phone novels create a personal space for each individual reader. Paul Levinson, in Information on the Move (2004), says "...nowadays, a writer can write just about as easily, anywhere, as a reader can read" and they are "not only personal but portable".
Privacy
Cell phones have numerous privacy issues associated with them, and are regularly used by governments to perform surveillance.
Law enforcement and intelligence services in the U.K. and the United States possess technology to remotely activate the microphones in cell phones in order to listen to conversations that take place nearby the person who holds the phone.[14][15]
Mobile phones are also commonly used to collect location data. The geographical location of a mobile phone can be determined easily (whether it is being used or not), using a technique known multilateration to calculate the differences in time for a signal to travel from the cell phone to each of several cell towers near the owner of the phone. [16][17]
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