A mobile phone is a portable telephone that can make and receive telephone call over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture and, therefore, mobile telephones are called cellular telephones or cell phones in North America. In addition to telephony, digital mobile phones support a variety of other GSM services, such as text messaging, multimedia messagIng, email, Internet access (via LTE, 5G NR or Wi-Fi), short-range wireless communications (infrared, Bluetooth), satellite access (navigation, messaging connectivity), business applications, video games and digital photography. Mobile phones offering only those capabilities are known as ; mobile phones which offer greatly advanced computing capabilities are referred to as .
The first handheld mobile phone was demonstrated by Martin Cooper of Motorola in New York City in 1973, using a handset weighing c. 2 kilograms (4.4 lbs). In 1979, Nippon Telegraph and Telephone (NTT) launched the world's first cellular network in Japan. In 1983, the Motorola DynaTAC was the first commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion; enough to provide one for every person on Earth. In the first quarter of 2016, the top smartphone developers worldwide were Samsung, Apple and Huawei; smartphone sales represented 78 percent of total mobile phone sales. For (slang: "dumbphones") , the top-selling brands were Samsung, HMD Global and Alcatel Mobile.
Mobile phones are considered an important human invention as it has been one of the most widely used and sold pieces of consumer technology. The growth in popularity has been rapid in some places, for example in the UK the total number of mobile phones overtook the number of houses in 1999. Today mobile phones are globally ubiquitous, and in almost half the world's countries, over 90% of the population own at least one.
The first handheld cellular mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing . The first commercial automated cellular network (1G) Analog signal was launched in Japan by Nippon Telegraph and Telephone in 1979. This was followed in 1981 by the simultaneous launch of the Nordic Mobile Telephone (NMT) system in Denmark, Finland, Norway, and Sweden. Several other countries then followed in the early to mid-1980s. These first-generation (1G) systems could support far more simultaneous calls but still used analog cellular technology. In 1983, the Motorola DynaTAC was the first commercially available handheld mobile phone.
In 1991, the second-generation (2G) digital cellular technology was launched in Finland by Radiolinja on the GSM standard. This sparked competition in the sector as the new operators challenged the incumbent 1G network operators. The GSM standard is a European initiative expressed at the CEPT ("Conférence Européenne des Postes et Telecommunications", European Postal and Telecommunications conference). The Franco-German R&D cooperation demonstrated the technical feasibility, and in 1987 a Memorandum of Understanding was signed between 13 European countries who agreed to launch a commercial service by 1991. The first version of the GSM (=2G) standard had 6,000 pages. The IEEE and RSE awarded to Thomas Haug and Philippe Dupuis the 2018 James Clerk Maxwell medal for their contributions to the first digital mobile telephone standard. In 2018, the GSM was used by over 5 billion people in over 220 countries. The GSM (2G) has evolved into 3G, 4G and 5G. The standardisation body for GSM started at the CEPT Working Group GSM (Group Special Mobile) in 1982 under the umbrella of CEPT. In 1988, ETSI was established and all CEPT standardization activities were transferred to ETSI. Working Group GSM became Technical Committee GSM. In 1991, it became Technical Committee SMG (Special Mobile Group) when ETSI tasked the committee with UMTS (3G).
In 2001, the third generation (3G) was launched in Japan by NTT DoCoMo on the WCDMA standard. This was followed by 3.5G, 3G+ or turbo 3G enhancements based on the high-speed packet access (HSPA) family, allowing UMTS networks to have higher data transfer speeds and capacity.
By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications, such as streaming media. Consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies. The first two commercially available technologies billed as 4G were the WiMAX standard, offered in North America by Sprint, and the LTE standard, first offered in Scandinavia by TeliaSonera.
5G is a technology and term used in research papers and projects to denote the next major phase in mobile telecommunication standards beyond the 4G/IMT-Advanced standards. The term 5G is not officially used in any specification or official document yet made public by telecommunication companies or standardization bodies such as 3GPP, WiMAX Forum or ITU-R. New standards beyond 4G are currently being developed by standardization bodies, but they are at this time seen as under the 4G umbrella, not for a new mobile generation.
Former systems would cover a service area with one or two powerful with a range of up to tens of kilometres (miles), using only a few sets of radio channels (frequencies). Once these few channels were in use by customers, no further customers could be served until another user vacated a channel. It would be impractical to give every customer a unique channel since there would not be enough bandwidth allocated to the mobile service. As well, technical limitations such as antenna efficiency and receiver design limit the range of frequencies a customer unit could use.
A cellular network mobile phone system gets its name from dividing the service area into many small cells, each with a base station with (for example) a useful range on the order of a kilometre (mile). These systems have dozens or hundreds of possible channels allocated to them. When a subscriber is using a given channel for a telephone connection, that frequency is unavailable for other customers in the local cell and in the adjacent cells. However, cells further away can re-use that channel without interference as the subscriber's handset is too far away to be detected. The transmitter power of each base station is coordinated to efficiently service its own cell, but not to interfere with the cells further away.
Automation embedded in the customer's handset and in the base stations control all phases of the call, from detecting the presence of a handset in a service area, temporary assignment of a channel to a handset making a call, interface with the land-line side of the network to connect to other subscribers, and collection of billing information for the service. The automation systems can control the "hand off" of a customer handset moving between one cell and another so that a call in progress continues without interruption, changing channels if required. In the earliest mobile phone systems by contrast, all control was done manually; the customer would search for an unoccupied channel and speak to a mobile operator to request connection of a call to a landline number or another mobile. At the termination of the call the mobile operator would manually record the billing information.
Mobile phones communicate with cell towers that are placed to give coverage across a telephone service area, which is divided up into 'cells'. Each cell uses a different set of frequencies from neighboring cells, and will typically be covered by three towers placed at different locations. The cell towers are usually interconnected to each other and the phone network and the internet by wired connections. Due to bandwidth limitations each cell will have a maximum number of cell phones it can handle at once. The cells are therefore sized depending on the expected usage density, and may be much smaller in cities. In that case much lower transmitter powers are used to avoid broadcasting beyond the cell.
In order to handle the high traffic, multiple towers can be set up in the same area (using different frequencies). This can be done permanently or temporarily such as at special events or in disasters. Cell phone companies will bring a truck with equipment to host the abnormally high traffic.
Capacity was further increased when phone companies implemented digital networks. With digital, one frequency can host multiple simultaneous calls.
Additionally, short-range Wi-Fi infrastructure is often used by smartphones as much as possible as it offloads traffic from cell networks on to local area networks.
Low-end mobile phones are often referred to as and offer basic telephony. Handsets with more advanced computing ability through the use of native software applications are known as .
Mobile CPU performance depends not only on the clock rate (generally given in multiples of hertz) but also the memory hierarchy also greatly affects overall performance. Because of these problems, the performance of mobile phone CPUs is often more appropriately given by scores derived from various standardized tests to measure the real effective performance in commonly used applications.
Screen sizes are often measured in diagonal or ; feature phones generally have screen sizes below . Phones with screens larger than are often called "." Smartphones with screens over in size are commonly difficult to use with only a single hand, since most thumbs cannot reach the entire screen surface; they may need to be shifted around in the hand, held in one hand and manipulated by the other, or used in place with both hands. Due to design advances, some modern smartphones with large screen sizes and "edge-to-edge" designs have compact builds that improve their ergonomics, while the shift to taller aspect ratios have resulted in phones that have larger screen sizes whilst maintaining the ergonomics associated with smaller 16:9 displays.
Liquid-crystal displays are the most common; others are IPS panel, LED, OLED, and AMOLED displays. Some displays are integrated with pressure-sensitive digitizers, such as those developed by Wacom and Samsung, and Apple's "3D Touch" system.
A hybrid mobile phone can hold up to four SIM cards, with a phone having a different IMEI for each SIM Card. SIM and R-UIM cards may be mixed together to allow both GSM and CDMA networks to be accessed. From 2010 onwards, such phones became popular in emerging markets, and this was attributed to the desire to obtain the lowest calling costs.
When the removal of a SIM card is detected by the operating system, it may deny further operation until a reboot.
A common data application on mobile phones is SMS (SMS) text messaging. The first SMS 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 first mobile news service, delivered via SMS, was launched in Finland in 2000, and subsequently many organizations provided "on-demand" and "instant" news services by SMS. Multimedia Messaging Service (MMS) was introduced in March 2002.
+ Market share of top-five worldwide mobile phone vendors, Q2 2022 | ||||
21% | ||||
16% | ||||
13% | ||||
10% | ||||
9% | ||||
31% | ||||
Note: Vendor shipments are branded shipments and exclude OEM sales for all vendors. |
As of 2022, the top five manufacturers worldwide were Samsung (21%), Apple (16%), Xiaomi (13%), Oppo (10%), and Vivo (9%).
Aside from Motorola, European brands such as Nokia, Siemens and Ericsson once held large sway over the global mobile phone market, and many new technologies were pioneered in Europe. By 2010, the influence of European companies had significantly decreased due to fierce competition from American and Asian companies, to where most technical innovation had shifted. Apple and Google, both of the United States, also came to dominate mobile phone software.
The mobile phone has been used in a variety of diverse contexts in society. For example:
Branchless banking has also been successful in South Africa and the Philippines. A pilot project in Bali was launched in 2011 by the International Finance Corporation and an bank, Bank Mandiri.
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 country's first commercial mobile payments systems with mobile operators Globe Telecom and Smart.
Some mobile phones can make via direct mobile billing schemes, or through contactless payments if the phone and the point of sale support near field communication (NFC). Enabling contactless payments through NFC-equipped mobile phones requires the co-operation of manufacturers, network operators, and retail merchants.
The movements of a mobile phone user can be tracked by their service provider and, if desired, by law enforcement agencies and their governments. Both the SIM card and the handset can be tracked.
China has proposed using this technology to track the commuting patterns of Beijing city residents. In the UK and US, law enforcement and intelligence services use mobile phones to perform surveillance operations.
Hackers have been able to track a phone's location, read messages, and record calls, through obtaining a subscribers phone number.
A 2011 study reported that over 90% of college students surveyed text (initiate, reply or read) while driving. The scientific literature on the dangers of driving while sending a text message from a mobile phone, or texting while driving, is limited. A simulation study at the University of Utah found a sixfold increase in distraction-related accidents when texting.
Due to the increasing complexity of mobile phones, they are often more like mobile computers in their available uses. This has introduced additional difficulties for law enforcement officials when attempting to distinguish one usage from another in drivers using their devices. This is more apparent in countries which ban both handheld and hands-free usage, rather than those which ban handheld use only, as officials cannot easily tell which function of the mobile phone is being used simply by looking at the driver. This can lead to drivers being stopped for using their device illegally for a phone call when, in fact, they were using the device legally, for example, when using the phone's incorporated controls for car stereo, GPS or satnav.
A 2010 study reviewed the incidence of mobile phone use while cycling and its effects on behaviour and safety.de Waard, D., Schepers, P., Ormel, W. and Brookhuis, K., 2010, Mobile phone use while cycling: Incidence and effects on behaviour and safety, Ergonomics, Vol 53, No. 1, January 2010, pp. 30–42. In 2013, a national survey in the US reported the number of drivers who reported using their cellphones to access the Internet while driving had risen to nearly one of four. A study conducted by the University of Vienna examined approaches for reducing inappropriate and problematic use of mobile phones, such as using mobile phones while driving.
Accidents involving a driver being distracted by talking on a mobile phone have begun to be prosecuted as negligence similar to speeding. In the United Kingdom, from 27 February 2007, motorists who are caught using a hand-held mobile phone while driving will have three penalty points added to their license in addition to the fine of £60. This increase was introduced to try to stem the increase in drivers ignoring the law. Japan prohibits all mobile phone use while driving, including use of hands-free devices. New Zealand has banned hand-held cell phone use since 1 November 2009. Many states in the United States have banned texting on cell phones while driving. Illinois became the 17th American state to enforce this law. , 30 states had banned texting while driving, with Kentucky becoming the most recent addition on 15 July.
Public Health Law Research maintains a list of distracted driving laws in the United States. This database of laws provides a comprehensive view of the provisions of laws that restrict the use of mobile communication devices while driving for all 50 states and the District of Columbia between 1992 when first law was passed, through 1 December 2010. The dataset contains information on 22 dichotomous, continuous or categorical variables including, for example, activities regulated (e.g., texting versus talking, hands-free versus handheld), targeted populations, and exemptions.
On 31 May 2011, the World Health Organization stated that mobile phone use may possibly represent a long-term health risk, classifying mobile phone radiation as "possibly carcinogenic to humans" after a team of scientists reviewed studies on mobile phone safety. The mobile phone is in category 2B, which ranks it alongside coffee and other possibly carcinogenic substances.
Some recent studies have found an association between mobile phone use and certain kinds of brain and salivary gland tumors. Lennart Hardell and other authors of a 2009 meta-analysis of 11 studies from peer-reviewed journals concluded that cell phone usage for at least ten years "approximately doubles the risk of being diagnosed with a brain tumor on the same ('ipsilateral') side of the head as that preferred for cell phone use".
One study of past mobile phone use cited in the report showed a "40% increased risk for gliomas (brain cancer) in the highest category of heavy users (reported average: 30 minutes per day over a 10‐year period)". This is a reversal of the study's prior position that cancer was unlikely to be caused by cellular phones or their base stations and that reviews had found no convincing evidence for other health effects. However, a study published 24 March 2012, in the British Medical Journal questioned these estimates because the increase in brain cancers has not paralleled the increase in mobile phone use. Certain countries, including France, have warned against the use of mobile phones by minors in particular, due to health risk uncertainties. Mobile pollution by transmitting electromagnetic waves can be decreased up to 90% by adopting the circuit as designed in mobile phone and mobile exchange.
In May 2016, preliminary findings of a long-term study by the U.S. government suggested that radio-frequency (RF) radiation, the type emitted by cell phones, can cause cancer.
The average user replaces their mobile phone every 11 to 18 months, and the discarded phones then contribute to electronic waste. Mobile phone manufacturers within Europe are subject to the WEEE directive, and Australia has introduced a mobile phone recycling scheme.
Apple Inc. had an advanced robotic disassembler and sorter called Liam specifically for recycling outdated or broken iPhones.
All mobile phones have a unique identifier called IMEI. Anyone can report their phone as lost or stolen with their Telecom Carrier, and the IMEI would be blacklisted with a central registry. Telecom carriers, depending upon local regulation can or must implement blocking of blacklisted phones in their network. There are, however, a number of ways to circumvent a blacklist. One method is to send the phone to a country where the telecom carriers are not required to implement the blacklisting and sell it there, another involves altering the phone's IMEI number. Even so, mobile phones typically have less value on the second-hand market if the phones original IMEI is blacklisted.
In Israel, similar phones to kosher phones with restricted features exist to observe the Shabbat; under Orthodox Judaism, the use of any electrical device is generally prohibited during this time, other than to save lives, or reduce the risk of death or similar needs. Such phones are approved for use by essential workers, such as health, security, and public service workers.
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