Cell Phones

Cell Phones



Cell phones (cellular phone), also known as a mobile phones, are electronic telecommunications device with the same basic capability as a conventional fixed-line telephone, but which is also entirely portable and is not required to be connected with a wire to the telephone network. Most current mobile phones connect instead to the network using a wireless radio wave transmission technology. The mobile phone communicates via a cellular network of base stations, also known as cell sites, which are in turn linked to the conventional telephone network.


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, Fujitsu, Kyocera (formerly the handset division of Qualcomm), LG, Motorola, NEC, Nokia, Panasonic (Matsushita Electric), Philips, Sagem, Samsung, Sanyo, Sharp, Siemens, SK Teletech, Sony Ericsson, and Toshiba.

 

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World Wide Deployment of Cell Phones

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.
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In most of Europe, wealthier parts of Asia and Latin America, Australia, Canada and the US, 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 all working to the same standard, particularly the GSM standard which was designed for Europe-wide interoperability. All European nations and some Asian nations chose it as their sole standard, while in Japan and South Korea another standard, CDMA, was selected.​

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Mobile Phone Culture


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 email.


The mobile phone itself has also become a totemic 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.


Mobile phone etiquette has become an important issue with mobiles ringing at funerals, weddings, movies and plays. Users often speak at increased volume, with little regard for other people nearby. It has become common practice for places like bookshops, libraries, movie theatres, and houses of worship to post signs prohibiting the use of mobile phones, sometimes even installing jamming equipment to prevent them. The US intercity passenger system Amtrak offers 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.


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.

 

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Mobile Phone 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 waves with a base station (which can be located on top of a building or on a tower designed for the purpose). The phones have a low power transceiver that is typically designed to transmit voice and data up to a few kilometers to where the tower is located. The handset constantly listens for the nearest tower with the strongest signal. Once found, the handset informs that tower of its own unique identifier, and alerts the mobile phone network that it is ready and standing-by to receive telephone calls. This cycle is then repeated as the phone roams around the network and new towers appear in the handset's range.


Towers have high power radio transmitters which broadcast their presence, and relay communications to and from the mobile handsets. The tower is connected to the telephone network by a high-capacity link. The base station connects to the operator's backbone network and the wider public telephone network as well as the networks of other mobile phone operators.


The dialogue between the handset and the tower is a stream of digitized audio. The technology that achieves this depends on the system which the mobile phone operator has adopted. Some technologies include AMPS for analogue, and TDMA, CDMA, GSM, GPRS and UMTS for digital communications. Each network operator also has a unique radio frequency chosen from a small number of standard frequencies allocated to each technology.

 

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Mobile Phone Controversy


Health controversy
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 mutations.


Driving controversy
Another controversial but more lethal health concern is the correlation with road traffic accidents. 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. One such study 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. In some jurisdictions, such as Ireland, Japan, Singapore, Brazil, Australia, Austria, the United Kingdom the Netherlands, Italy, Poland and France, as well as several states in the United States, driving while using a mobile phone is illegal, though an exception is often made if the phone is equipped with a hands-free system. In Canada it is banned in Newfoundland (Dec. 2002) with fines up to US$180.


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 eaves drop 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.

 

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Mobile Phone's Future


Mobile Phone's Future
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:


One difficulty in adapting mobile phones to new uses is form factor. For example, ebooks may well become a distinct device, because of conflicting form-factor requirements — ebooks require large screens, while phones need to be smaller. However, this may be solved using folding e-paper or built-in projectors .

One function that would be useful in phones is a translation function. Currently it is only available in stand-alone devices, such as Ectaco translators.

An important area of evolution relates to the Man Machine Interface. New solutions are being developed to create new MMI more easily and let manufacturers and operators experiment new concepts. Examples of companies that are currently developing this technology are Digital Airways with the Kaleido product, e-sim, mobile arsenal, and Qualcomm with UIOne for the BREW environment.

Mobile phones will include various speech technologies as they are being developed. Many phones already have rudimentary speech recognition in a form of voice dialing. However, to support more natural speech recognition and translation, a drastic improvement in the state of technology in these devices is required.

New technologies are being explored that will utilize the Extended Internet and enable mobile phones to treat a barcode as a URL tag. Phones equipped with barcode reader-enabled cameras will be able to snap photos of barcodes and direct the user to corresponding sites on the Internet. This technology can be extended to RFID tags, or even snapped pictures of company logos. Searches can also be personalized to local areas using a GPS system built in to cell phones. Examples of companies that are currently developing this technology are Neomedia (via Paperclick), Mobot and Scanbuy.
Developments in miniaturised hard disks and flash drives to solve the storage space issue are already surfacing, therefore opening a window for phones to become portable music libraries and players similar to the iPod.

Developments in podcast software enables mobile phones to become podcast playback devices through existing channels like MMS Podcast, J2ME Podcast and AMR-NB Podcast.
The emergence of integration capabilities with other unlicensed access technologies such as a WiMAX and WLAN, as well as allowing handover between traditional operator networks supporting GSM, CDMA and UMTS to unlicensed mobile networks. The new standard (UMA) has been developed for this.

Further improvements in battery life will be required. Colour screens and additional functions put increasing demands on the device's power source, and battery developments may not proceed sufficiently fast to compensate. However, different display technologies, such as OLED displays, e-paper or retinal displays, smarter communication hardware ( directional antennae, multi-mode and peer-to-peer phones) may reduce power requirements, while new power technologies such as fuel cells may provide better energy capacity.

Speculative improvements in the future may be inspired by an English team led by James Auger and Jimmy Loizeau who in 2002 developed an implant designed to be inserted into a tooth during dental surgery. This device consists of a radio receiver and transducer, which transmits the sound via bone conduction through the jawbone into the ear. Sound is transmitted via radio waves from another device (presumably a mobile phone) and received by the implant. The implant is currently powered externally, given that no current power source is small enough to fit inside the tooth with it. In addition, the implant was only designed to receive signals, not transmit them. Directly tapping into the inner ear or the auditory nerve is already technologically feasible and will become practical as surgical methods advance.

New technology in Japan has combined the RFID chip principle into the handset and hooked it up to a network of readers and interfaces. The system, pioneered by NTT DoCoMo and SonyEricsson, is called Felica and there are around 10,000 convenience stores where one can now use a phone to pay for goods just by 'swiping' it over a flat reader. By charging up a phone with pre-paid cash credits, it can act as a sophisticated mobile-phone wallet. The technology is proving popular and there are now even vending machines that accept this form of payment.

The delivery of multimedia content including video to mobiles is beginning to become a reality with two main competing standards DMB - Digital Multimedia Broadcasting - and DVB-H - a handset version of the Digital Video Broadcasting standard. These methods avoid swamping the network by using traditional broadcasting.

Image scanning, as seen in existing research. With time, this may develop into full 3D texturing and modeling. It is unlikely that cell phones will have the processing power to construct models and textures. But it is likely that the bandwidth to communicate the video, and receive a processed model will exist.

There are several cell phones that can perform GPS positioning. In the future, GPS positioning may be coupled with accelerometer positioning, for covering underground or indoor positioning. This would likely lead to maps and help finding where you are going, and supports social efforts, such as locating friends or group members nearby, and identifying some strangers.