Mobile phone
From Wikipedia, the free encyclopedia(Redirected from Mobile phones)
Several examples of non-folding mobile phones.
The mobile phone or cell phone is a long-range, portable electronic
device used for mobile communication. In addition to the standard voice
function of a telephone,
current mobile phones 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. 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).
- GSM
- GPRS
- EDGE (EGPRS)
- EDGE Evolution
(Evolved EDGE)
- HSCSD
3GPP2: cdmaOne / CDMA2000
Family
Other Technologies
[edit] History
Main article: History of mobile phones
Various cell phones from the past 10–15 years.
Legend:
1. NEC Cellstar 500
series (1992)
2. Nokia 2110
series (1994)
3. Nokia 5120
(1998)
4. Kyocera
2135 (2002)
5. Audiovox
CDM8300 (2002)
6. Samsung
SCH-A650 (2004)
There is one U.S. patent, Patent Number 887357 for a wireless telephone,
issued 1908 to Nathan B. Stubblefield of Murray,
Kentucky. He applied this to "cave radio" telephones and not
directly to cellular telephony as we know it today.[1]
However, the introduction of cells for mobile phone base stations, invented in
1947 by Bell
Labs engineers at AT&T,
was 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 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.[citation needed]
In 1945, the zero generation (0G) of mobile telephones was introduced. 0G mobile telephones,
such as Mobile Telephone Service, were not
officially categorized as mobile phones, since they did not support the
automatic change of channel frequency during calls, which allows the user to
move from one cell (the base station coverage area) to another cell, a
feature called "handover".[citation needed]
In 1984, Bell
Labs invented such a "call handoff" feature, which allowed
mobile-phone users to travel through several cells during the same
conversation. Motorola
is widely considered to be the inventor of the first practical mobile phone for
handheld use in a non-vehicle setting. Using a modern, if somewhat heavy
portable handset, Motorola manager Martin
Cooper made the first call on a handheld mobile phone on April 3, 1973.[2]
The first commercial 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) with the Nordic Mobile Telephone (NMT) system in
1981. This was followed by a boom in mobile telephone usage, particularly in
Northern Europe.[citation needed]
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. A decade later, the first commercial launch of 3G
(Third Generation) was again in Japan by NTT DoCoMo on the WCDMA standard.[citation needed] 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, mobile phones
have become increasingly handy over the years.
Today, video and TV services are driving forward third generation (3G)
deployment. And in the future, low cost, high speed data will driveforward the
fourth generation (4G) as short-range communication emerges.Service and
application ubiquity, with a high degree of personalization and synchronization
between various user appliances,will be another driver. At the same time, it is
probable that the radio access network will evolve from a centralized architecture
to a distributed one.
[edit] Manufacturers
Nokia Corporation is currently the world's
largest manufacturer of mobile telephones, with a global device market share of
approximately 36% in Q1 of 2007.[3]
Other mobile phone manufacturers include Apple Inc.,
Audiovox
(now UT Starcom), Benefon, BenQ-Siemens, High Tech Computer Corporation (HTC), Fujitsu, Kyocera, LG Mobile, Mitsubishi,
Motorola, NEC,
Neonode, Panasonic
(Matsushita Electric), Pantech Curitel, Philips, Research In Motion, Sagem, Samsung, Sanyo, Sharp,
Siemens,
Sierra
Wireless, SK Teletech, Sonim Technologies, Sony
Ericsson, T&A Alcatel,Toshiba, and Verizon. There
are also specialist communication systems related to (but distinct from) mobile
phones.
The mobile phone manufacturers can be grouped into two. The top five are
available in practically all countries and comprise about 75% of all phones
sold. A second tier of small manufacturers exists with phones mostly sold only
in specific regions or for niche markets. The top five in order of market share
are Nokia, Samsung, Motorola, SonyEricsson and LG.
[edit] Subscriptions
This Railfone found on some Amtrak trains uses
cellular technology.
See
also: List of mobile network operators
Several countries, including the UK, now have more mobile phones than people.[4]
There are over five hundred million active mobile phone accounts in China, as
of 2007.[5]
Luxembourg
has the highest mobile phone penetration rate in the
world, at 164% in December 2001. In Hong Kong
the penetration rate reached 139.8% of the population in July 2007.[6] The total number of mobile phone subscribers in the
world was estimated at 2.14 billion in 2005.[7]
The subscriber count reached 2.7 billion by end of 2006 according to Informa.[citation needed] Around
80% of the world's population enjoys mobile phone coverage as of 2006.
This figure is expected to increase to 90% by the year 2010.[8]
At present, Africa has the largest growth rate of cellular subscribers in
the world,[9]
its markets expanding nearly twice as fast as Asian markets.[10] The availability of prepaid or 'pay-as-you-go' services, where the subscriber
is not committed to a long term contract, has helped fuel this growth to a
monumental scale in Africa as well as in other continents.
On a numerical basis, India is the largest growth market, adding about 6
million cell phones every month.[11]
With 156.31 million cell phones, market penetration in the country is still low
at 17.45% India expects to reach 500 million subscribers by end of 2010.
There are three major technical standards for the current generation of
mobile phones and networks, and two major standards for the next generation 3G
phones and networks. All European countries and African countries and many
Asian countries have adopted a single system, GSM, which is the only technology
available on all continents and in most countries and covers over 74% of all
subscribers on mobile networks. In many countries, such as the United
States, Australia,
Brazil, India, Japan, and South Korea
GSM co-exists with other internationally adopted standards such as CDMA and TDMA, as well
as national standards such as iDEN in the USA and PDC in
Japan. Over the past five years several dozen mobile operators (carriers) have
abandoned networks on TDMA and CDMA technologies, switching over to GSM.
With third generation (3G) networks, which are also known as IMT-2000
networks, about three out of four networks are on the W-CDMA (also known
as UMTS) standard, usually
seen as the natural evolution path for GSM and TDMA networks. One in four 3G
networks is on the CDMA2000 1x EV-DO technology. Some analysts count a previous
stage in CDMA evolution, CDMA2000 1x RTT, as a 3G technology whereas most
standardization experts count only CDMA2000 1x EV-DO as a true 3G technology.
Because of this difference in interpreting what is 3G, there is a wide variety
in subscriber counts. As of June 2007, on the narrow definition there are 200
million subscribers on 3G networks. By using the more broad definition, the total
subscriber count of 3G phone users is 475 million.
While some systems of payment are 'pay-as-you-go' where conversation time is
purchased and added to a phone unit via an Internet account or in shops or
ATMs, other systems are more traditional ones where bills are paid by regular
intervals. Pay as you go (also known as "pre-pay") accounts were
invented simultaneously in Portugal and Italy and today form more than half of
all mobile phone subscriptions. USA, Canada, Japan and Finland are among the
rare countries left where most phones are still contract-based.
[edit] Culture and customs
In less than twenty years, the mobile telephone has gone from being rare,
expensive equipment of the business elite to a pervasive, low-cost personal
item. In many countries, mobile telephones outnumber land-line telephones; in
the U.S., 50 percent of children have mobile telephones.[12]
In many young
adults' households it has supplanted the land-line telephone. The mobile
phone is banned in some countries, such as North Korea.[13]
Given the high levels of societal mobile telephone service penetration, it
is a key means for people to communicate with each other. The SMS feature spawned the "texting"
sub-culture.[citation needed] In
December 1993, the first person-to-person SMS text message was transmitted in
Finland. Currently, texting is the most widely-used data service; 1.8 billion
users generated $80 billion of revenue in 2006 (source ITU).
Many telephones offer Instant
Messenger services for simple, easy texting. Mobile phones have Internet
service (e.g. NTT DoCoMo's i-mode), offering
text messaging via e-mail in Japan, South Korea, China, and India. In Europe,
30–40 per cent of internet access is via mobile telephone. Most mobile internet
access is much different from computer access, featuring alerts, weather data,
e-mail, search engines, instant messages, and game and music downloading; most
mobile internet access is hurried and short.
Currently, the mobile telephone is a fashion totem
custom-decorated to reflect the owner's personality. This aspect of the mobile
telephony business is, in itself, an industry, e.g. ringtone sales
exceeded $5 billion in 2006, per Informa.[citation needed]
[edit] Etiquette
The use of a mobile phone is prohibited in some train company
carriages
Mobile telephone use etiquette is an important matter of social discourtesy,
phones ringing during funerals, weddings, in toilets, cinemas, and plays. Users
often speak loudly, leading to book shops, libraries, bathrooms, cinemas, doctors'
offices, and houses of worship prohibiting their uses, and, in
some places, the installation of signal-jamming
equipment to prevent their use (though in many countries, including the
U.S., such equipment is currently illegal). Some new buildings, such as
auditoriums, have installed wire mesh in the walls (making it a Faraday
cage) which prevents signal penetration that does not violate signal
jamming laws.
Trains, particularly those involving long-distance services, often offer a
"quiet car" where phone use is prohibited, much like the designated
non-smoking car in the past. However many users tend to ignore this as it is
rarely enforced, especially if the other cars are crowded and they have no
choice but to go in the "quiet car". Mobile phone use on aircraft is also
prohibited and many airlines claim in their in-plane announcements that this
prohibition is due to possible interference with aircraft radio communications.
Shut-off mobile phones do not interfere with aircraft avionics. The nuisance of
telephones on while aeroplanes take off and land, is that they disrupt the
ground mobile telephone networks.[citation needed]
As customers want to be connected on planes, now several airlines are
experimenting with base station and antenna systems installed to the aeroplane,
allowing low power, short-range connection of any phones aboard to remain
connected to the aircraft's base station.[citation needed] Thus,
they would not attempt connection to the ground base stations as during take
off and landing.[citation needed]
Simultaneously, airlines could offer phone services to their traveling
passengers either as full voice and data services, or initially only as SMS
text messaging and similar services. Qantas, the Australian airline, is the
first airline to run a test airplane in this configuration in the Autumn of
2007.[citation needed] Emirates
have announced plans to allow limited mobile phone usage on some flights.[citation needed]
In any case, there are inconsistencies between practices allowed by
different airlines and even on the same airline in different countries. For
example, Northwest Airlines may allow the use of mobile
phones immediately after landing on a domestic flight within the US, whereas
they may state "not until the doors are open" on an international
flight arriving in the Netherlands. In April 2007 the US Federal Communications Commission
officially grounded the idea of allowing passengers to use phones during a
flight.[14]
In a similar vein, signs are put up in UK petrol
stations prohibiting the use of mobile phones, due to possible safety
issues. Most schools in the United States have prohibited mobile phones in the
classroom, due to the large number of class disruptions that result from their
use, the potential for cheating via text messaging, and the possibility of
photographing someone without consent.[citation needed] In the
UK, possession of a mobile phone in an examination can result in immediate
disqualification from that subject or from all that student's subjects.[15]
A working group, made up of Finnish telephone companies, public transport
operators and communications authorities, have launched a campaign to remind
mobile phone users of courtesy, especially when using mass transit – what to
talk about on the phone, and how to. In particular, the campaign wants to
impact loud mobile phone usage as well as calls regarding sensitive matters.[16]
[edit] Use in disaster response
The Finnish government decided in 2005 that the fastest way to warn citizens
of disasters was the mobile phone network. In Japan, mobile phone companies
provide immediate notification of earthquakes
and other natural disasters to their customers free of
charge.[citation needed] 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.[citation needed] In Finland
rescue services suggest hikers carry mobile phones in case of emergency even
when deep in the forests beyond cellular coverage, as the radio signal of a
cellphone attempting to connect to a base station can be detected by overflying
rescue aircraft with special detection gear. Also, users in the United States
can sign up through their provider for free text messages when an AMBER Alert
goes out for a missing person in their area.
[edit] Use
by drivers
One phone in each hand
Main article: Mobile phones and driving safety
Mobile-phone use while driving is common but controversial. While few jurisdictions
have banned motorists from using mobile phones while driving outright, some
have banned or restricted drivers from using hand-held mobile phones
while exempting phones operated in a hands-free fashion. Using a
hand-held mobile phone while driving is an impediment to vehicle operation that
can increase the risk of road traffic accidents. However, some studies
have found similarly elevated accident rates among drivers using hands-free phones,
suggesting that the distraction of a telephone conversation itself is a
significant safety problem.[17]
This problem does not apply to conversations with a passenger, as
passengers can regulate the flow of conversation according to the perceived
level of danger, and also provides a second pair of eyes to spot hazards. [18]
[edit] Applications
Mobile
news services are expanding with many organizations 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[19]
and small independent news companies such as Jasmine News in Sri Lanka. Companies like Monster[20] 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,
e.g. Mobilemo.
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.
[edit] Power
Mobile phones generally obtain power from batteries which can be recharged from mains power,
a USB port or a
cigarette lighter socket in a car. Formerly, the most common form of cell 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. Cell phone manufacturers have
been experimenting with alternate power sources.
This short section requires expansion.
[edit] Features
Main article: Mobile phone features
There are significant questions as to who first invented the camera phone,
as numerous other people received patents filed in the early 1990s for the
device, including David M. Britz of AT&T Research in March of 1994 and Phillipe
Kahn, who claims to have first invented it in 1997.[citation needed] The camera
phone now holds 85% of the mobile phone market[citation needed]. Mobile
phones often have features beyond sending text messages and making voice calls,
including Internet browsing, music (MP3) playback, memo recording, personal organizer functions, e-mail, instant
messaging, built-in cameras and camcorders, ringtones,
games, radio, Push-to-Talk (PTT), infrared and Bluetooth connectivity,
call registers, ability to watch streaming video or download video for later
viewing, video calling and serve 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 (e.g. Final Fantasy Agito).[citation needed]
[edit] Tariff
models
See
also: GSM services#Voice charges
When cellular telecoms services were launched, phones and calls were very
expensive and early mobile operators (carriers) decided to charge for all air
time consumed by the mobile phone user. This resulted in the concept of
charging callers for outbound calls and also for receiving calls. As mobile
phone call charges diminished and phone adoption rates skyrocketed, more modern
operators decided not to charge for incoming calls. Thus some markets have
"Receiving Party Pays" models (or, more correctly, "Mobile
Party Pays"), in which both outbound and received calls are charged,
and other markets have "Calling Party Pays" models, by which only
making calls produces costs, and receiving calls is free. An exception to this
are international
roaming tariffs, by which receiving calls are normally also charged.[citation needed]
The European market adopted a "Calling Party Pays" model
throughout the GSM environment and soon various other GSM markets also started
to emulate this model. As Receiving Party Pays systems have the undesired
effect of phone owners keeping their phones turned off to avoid receiving
unwanted calls, the total voice usage rates (and profits) in Calling Party Pays
countries outperform those in Receiving Party Pays countries. Consequently,
most countries previously with Receiving Party Pays models have either
abandoned them or employed alternative marketing methods, such as massive voice
call buckets, to avoid the problem of phone users keeping phones turned off.[citation needed]
In most countries today, including European
Union nations, United Arab Emirates, Kazakhstan,
Turkey, New Zealand,
Korea, Japan, Pakistan, Australia, Brazil, Chile, Colombia, India,[21] Maldives, Malaysia, Peru, South Africa, Israel, Lebanon and Jordan the person
receiving a mobile phone call pays nothing. However, in Hong Kong, Canada, and the United
States, one can be charged per minute. In the United States, a few carriers
are beginning to offer unlimited received phone calls. For the Chinese mainland,
it was reported that both of its two operators will adopt the caller-pays
approach as early as January 2007.[21]
[edit] Developing countries
In some developing countries with little telephone infrastructure,
the mobile telephone is the telephony giving poor people access to medical and
legal services. Cell phone use in developing countries has quadrupled in the
last decade.[22].
The rise of cell phone technology in developing countries is often cited as an
example of the leapfrog effect. In many remote regions in the
third world went literally from having no telecommunications infrastructure to
having satellite based communications systems.
[edit] Forensics and evidence
Law enforcement globally rely heavily upon mobile telephone evidence, to the
extent that in the EU the "communications of every mobile telephone user
are recorded"[23].
The concerns over terrorism and terrorist use of technology prompted an
inquiry by the British House of Commons Home Affairs Select Committee into
the use of evidence from mobile telephone devices, prompting leading mobile
telephone forensic specialists to identify forensic techniques available in
this area.[24]
NIST have published guidelines and procedures for the preservation,
acquisition, examination, analysis, and reporting of digital information
present on cell phones can be found under the NIST Publication SP800-101.[25]
An example of criminal investigations using mobile phones is the initial
location and ultimate identification of the terrorists of the 2004 Madrid train bombings. In the
attacks, mobile phones had been used to detonate the bombs. However, one of the
bombs failed to detonate, and the SIM card in the corresponding mobile
phone gave the first serious lead about the terrorists to investigators. By
tracking the whereabouts of the SIM card and correlating other mobile phones
that had been registered in those areas, police were able to locate the
terrorists.[citation needed]
[edit] Human health impacts
Main article: Mobile phone radiation and health
Since the introduction of mobile phones, concerns have been raised about the
potential health impacts from regular use.[26]
As mobile phone penetrations grew past fixed landline penetration levels in
1998 in Finland and from 1999 in Sweden, Denmark and Norway, the Scandinavian
health authorities have run continuous long term studies of effects of mobile
phone radiation effects to humans, and in particular children. Numerous studies
have reported and most studies consistently report no significant relationship
between mobile phone use and health. Studies from the Institute of Cancer
Research, National Cancer Institute and researchers at the Danish Institute of
Cancer Epidemiology in Copenhagen for example showed no link between mobile
phone use and cancer.[27][28]
The Danish study only covered analog mobile phone usage up through 1995, and
subjects who started mobile phone usage after 1995 were counted as non-users in
the study.[29]
The health concerns have grown as mobile phone penetration rates throughout
Europe reached 80%–90% levels earlier in this decade and prolonged exposure
studies have been carried out in almost all European countries again most
reporting no effect, and the most alarming studies only reporting a possible
effect. However, a study by the International Agency for
Research on Cancer of 4,500 users found a statistically significant link
between tumor frequency and mobile phone use.[30]
The link between cellphones and low sperm quality suggests that the radiation
emitting from mobile phones may be potentially dangerous and should be
considered as such.[31]
[edit] Environmental impacts
Like all high structures, cellular antenna masts pose a hazard to low flying
aircraft.
Towers over a certain height or towers that are close to airports or heliports are
normally required to have warning lights. There have been reports that warning
lights on cellular masts, TV-towers and other high structures can attract and
confuse birds. US authorities estimate
that millions of birds are killed near communication towers in the country each
year.[32]
An example of the way mobile phones and mobile networks have sometimes been
perceived as a threat is the widely reported and later discredited claim that
mobile phone masts are associated with the "Colony Collapse Disorder" (CCD) which
has reduced bee hive numbers by up to 75% in many areas, especially near cities
in the US. The Independent newspaper cited a scientific study claiming it
provided evidence for the theory that mobile phone masts are a major cause in
the collapse of bee populations, with controlled experiments demonstrating a
rapid and catastrophic effect on individual hives near masts.[33]
Mobile phones were in fact not covered in the study, and the original
researchers have since emphatically disavowed any connection between their
research, mobile phones, and CCD, specifically indicating that the Independent
article had misinterpreted their results and created "a horror story".[34][35][36] While the initial claim of damage to bees was widely
reported, the corrections to the story were almost non-existent in the media.
[edit] Technology
See
also: Cellular frequencies
Mobile phone tower
Cell Phone tower located in Lynnwood,
WA.
Mobile phones and the network they operate under vary significantly from
provider to provider, and country to country. However, all of them communicate
through electromagnetic radio waves 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 not more than
8 to 13 km (approximately 5 to 8 miles) away. When the mobile 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
various cell sites during calls, or while waiting (idle) between calls it will reselect 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. Many of these sites are
camouflaged to blend with existing environments, particularly in scenic areas.
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. The
technologies are grouped by generation. The first-generation systems started in
1979 with Japan, are all analog and include AMPS and NMT. Second-generation
systems, started in 1991 in Finland, are all digital and include GSM, CDMA and
TDMA. Third-generation networks, which are still being deployed, started with
Japan in 2001, are all digital, and offer high-speed data access in addition to
voice services and include W-CDMA (known also as UMTS), and CDMA2000
EV-DO. China will launch a third 3G technlogy on the TD-SCDMA standard. Each
network operator has a unique radio
frequency band.[citation needed]
[edit] Books about mobile communication
Since 2002, many books have been written on the social impact of mobile
phones:
- Agar, Jon, Constant
Touch: A Global History of the Mobile Phone, 2004 ISBN
1840465417
- Ahonen, Tomi, m-Profits:
Making Money with 3G Services, 2002, ISBN
0-470-84775-1
- Ahonen, Kasper and Melkko,
3G Marketing 2004, ISBN
0-470-85100-7
- Glotz, Peter &
Bertsch, Stefan, eds. Thumb Culture: The Meaning of Mobile Phones for Society,
2005
- Katz, James E. &
Aakhus, Mark, eds. Perpetual Contact: Mobile Communication, Private
Talk, Public Performance, 2002
- Kavoori, Anandam &
Arceneaux, Noah, eds. The Cell Phone Reader: Essays in Social
Transformation, 2006
- Levinson,
Paul, Cellphone: The Story of the World's Most Mobile Medium, and
How It Has Transformed Everything!, 2004 ISBN
1-4039-6041-0
- Ling, Rich, The Mobile Connection: the Cell Phone's
Impact on Society, 2004 ISBN
1558609369
- Ling, Rich and Pedersen,
Per, eds. Mobile Communications: Re-negotiation of the Social Sphere,
2005 ISBN
1852339314
- Nyíri, Kristóf, ed. Mobile
Communication: Essays on Cognition and Community, 2003
- Nyíri, Kristóf, ed. Mobile
Learning: Essays on Philosophy, Psychology and Education, 2003
- Nyíri, Kristóf, ed. Mobile
Democracy: Essays on Society, Self and Politics, 2003
- Nyíri, Kristóf, ed. A
Sense of Place: The Global and the Local in Mobile Communication, 2005
- Nyíri, Kristóf, ed. Mobile
Understanding: The Epistemology of Ubiquitous Communication, 2006
- Plant,
Dr. Sadie, on
the mobile – the effects of mobile telephones on social and individual
life, 2001
- Rheingold, Howard, Smart Mobs: The Next
Social Revolution, 2002 ISBN
0738208612
[edit] Terminology
[edit] Related non-mobile-phone systems
Cordless telephone (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. Increasingly, with wireless local loop technologies, namely DECT, the distinction
is blurred.
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. Also, they may require the assistance of a human operator to set
up a PSTN phone
call.
[edit] Terms in various countries
Further information: Mobile phone terms across the world
(Redirected from Mobile phones)
Several examples of non-folding mobile phones.
The mobile phone or cell phone is a long-range, portable electronic
device used for mobile communication. In addition to the standard voice
function of a telephone,
current mobile phones 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. 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).
|
|
|
|
3GPP2: cdmaOne / CDMA2000
Family |
|
Other Technologies |
|
|
[edit] History
Main article: History of mobile phones
Various cell phones from the past 10–15 years.
Legend:
1. NEC Cellstar 500
series (1992)
2. Nokia 2110
series (1994)
3. Nokia 5120
(1998)
4. Kyocera
2135 (2002)
5. Audiovox
CDM8300 (2002)
6. Samsung
SCH-A650 (2004)
There is one U.S. patent, Patent Number 887357 for a wireless telephone,
issued 1908 to Nathan B. Stubblefield of Murray,
Kentucky. He applied this to "cave radio" telephones and not
directly to cellular telephony as we know it today.[1]
However, the introduction of cells for mobile phone base stations, invented in
1947 by Bell
Labs engineers at AT&T,
was 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 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.[citation needed]
In 1945, the zero generation (0G) of mobile telephones was introduced. 0G mobile telephones,
such as Mobile Telephone Service, were not
officially categorized as mobile phones, since they did not support the
automatic change of channel frequency during calls, which allows the user to
move from one cell (the base station coverage area) to another cell, a
feature called "handover".[citation needed]
In 1984, Bell
Labs invented such a "call handoff" feature, which allowed
mobile-phone users to travel through several cells during the same
conversation. Motorola
is widely considered to be the inventor of the first practical mobile phone for
handheld use in a non-vehicle setting. Using a modern, if somewhat heavy
portable handset, Motorola manager Martin
Cooper made the first call on a handheld mobile phone on April 3, 1973.[2]
The first commercial 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) with the Nordic Mobile Telephone (NMT) system in
1981. This was followed by a boom in mobile telephone usage, particularly in
Northern Europe.[citation needed]
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. A decade later, the first commercial launch of 3G
(Third Generation) was again in Japan by NTT DoCoMo on the WCDMA standard.[citation needed] 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, mobile phones
have become increasingly handy over the years.
Today, video and TV services are driving forward third generation (3G)
deployment. And in the future, low cost, high speed data will driveforward the
fourth generation (4G) as short-range communication emerges.Service and
application ubiquity, with a high degree of personalization and synchronization
between various user appliances,will be another driver. At the same time, it is
probable that the radio access network will evolve from a centralized architecture
to a distributed one.
[edit] Manufacturers
Nokia Corporation is currently the world's
largest manufacturer of mobile telephones, with a global device market share of
approximately 36% in Q1 of 2007.[3]
Other mobile phone manufacturers include Apple Inc.,
Audiovox
(now UT Starcom), Benefon, BenQ-Siemens, High Tech Computer Corporation (HTC), Fujitsu, Kyocera, LG Mobile, Mitsubishi,
Motorola, NEC,
Neonode, Panasonic
(Matsushita Electric), Pantech Curitel, Philips, Research In Motion, Sagem, Samsung, Sanyo, Sharp,
Siemens,
Sierra
Wireless, SK Teletech, Sonim Technologies, Sony
Ericsson, T&A Alcatel,Toshiba, and Verizon. There
are also specialist communication systems related to (but distinct from) mobile
phones.
The mobile phone manufacturers can be grouped into two. The top five are
available in practically all countries and comprise about 75% of all phones
sold. A second tier of small manufacturers exists with phones mostly sold only
in specific regions or for niche markets. The top five in order of market share
are Nokia, Samsung, Motorola, SonyEricsson and LG.
[edit] Subscriptions
This Railfone found on some Amtrak trains uses
cellular technology.
See
also: List of mobile network operators
Several countries, including the UK, now have more mobile phones than people.[4]
There are over five hundred million active mobile phone accounts in China, as
of 2007.[5]
Luxembourg
has the highest mobile phone penetration rate in the
world, at 164% in December 2001. In Hong Kong
the penetration rate reached 139.8% of the population in July 2007.[6] The total number of mobile phone subscribers in the
world was estimated at 2.14 billion in 2005.[7]
The subscriber count reached 2.7 billion by end of 2006 according to Informa.[citation needed] Around
80% of the world's population enjoys mobile phone coverage as of 2006.
This figure is expected to increase to 90% by the year 2010.[8]
At present, Africa has the largest growth rate of cellular subscribers in
the world,[9]
its markets expanding nearly twice as fast as Asian markets.[10] The availability of prepaid or 'pay-as-you-go' services, where the subscriber
is not committed to a long term contract, has helped fuel this growth to a
monumental scale in Africa as well as in other continents.
On a numerical basis, India is the largest growth market, adding about 6
million cell phones every month.[11]
With 156.31 million cell phones, market penetration in the country is still low
at 17.45% India expects to reach 500 million subscribers by end of 2010.
There are three major technical standards for the current generation of
mobile phones and networks, and two major standards for the next generation 3G
phones and networks. All European countries and African countries and many
Asian countries have adopted a single system, GSM, which is the only technology
available on all continents and in most countries and covers over 74% of all
subscribers on mobile networks. In many countries, such as the United
States, Australia,
Brazil, India, Japan, and South Korea
GSM co-exists with other internationally adopted standards such as CDMA and TDMA, as well
as national standards such as iDEN in the USA and PDC in
Japan. Over the past five years several dozen mobile operators (carriers) have
abandoned networks on TDMA and CDMA technologies, switching over to GSM.
With third generation (3G) networks, which are also known as IMT-2000
networks, about three out of four networks are on the W-CDMA (also known
as UMTS) standard, usually
seen as the natural evolution path for GSM and TDMA networks. One in four 3G
networks is on the CDMA2000 1x EV-DO technology. Some analysts count a previous
stage in CDMA evolution, CDMA2000 1x RTT, as a 3G technology whereas most
standardization experts count only CDMA2000 1x EV-DO as a true 3G technology.
Because of this difference in interpreting what is 3G, there is a wide variety
in subscriber counts. As of June 2007, on the narrow definition there are 200
million subscribers on 3G networks. By using the more broad definition, the total
subscriber count of 3G phone users is 475 million.
While some systems of payment are 'pay-as-you-go' where conversation time is
purchased and added to a phone unit via an Internet account or in shops or
ATMs, other systems are more traditional ones where bills are paid by regular
intervals. Pay as you go (also known as "pre-pay") accounts were
invented simultaneously in Portugal and Italy and today form more than half of
all mobile phone subscriptions. USA, Canada, Japan and Finland are among the
rare countries left where most phones are still contract-based.
[edit] Culture and customs
In less than twenty years, the mobile telephone has gone from being rare,
expensive equipment of the business elite to a pervasive, low-cost personal
item. In many countries, mobile telephones outnumber land-line telephones; in
the U.S., 50 percent of children have mobile telephones.[12]
In many young
adults' households it has supplanted the land-line telephone. The mobile
phone is banned in some countries, such as North Korea.[13]
Given the high levels of societal mobile telephone service penetration, it
is a key means for people to communicate with each other. The SMS feature spawned the "texting"
sub-culture.[citation needed] In
December 1993, the first person-to-person SMS text message was transmitted in
Finland. Currently, texting is the most widely-used data service; 1.8 billion
users generated $80 billion of revenue in 2006 (source ITU).
Many telephones offer Instant
Messenger services for simple, easy texting. Mobile phones have Internet
service (e.g. NTT DoCoMo's i-mode), offering
text messaging via e-mail in Japan, South Korea, China, and India. In Europe,
30–40 per cent of internet access is via mobile telephone. Most mobile internet
access is much different from computer access, featuring alerts, weather data,
e-mail, search engines, instant messages, and game and music downloading; most
mobile internet access is hurried and short.
Currently, the mobile telephone is a fashion totem
custom-decorated to reflect the owner's personality. This aspect of the mobile
telephony business is, in itself, an industry, e.g. ringtone sales
exceeded $5 billion in 2006, per Informa.[citation needed]
[edit] Etiquette
The use of a mobile phone is prohibited in some train company
carriages
Mobile telephone use etiquette is an important matter of social discourtesy,
phones ringing during funerals, weddings, in toilets, cinemas, and plays. Users
often speak loudly, leading to book shops, libraries, bathrooms, cinemas, doctors'
offices, and houses of worship prohibiting their uses, and, in
some places, the installation of signal-jamming
equipment to prevent their use (though in many countries, including the
U.S., such equipment is currently illegal). Some new buildings, such as
auditoriums, have installed wire mesh in the walls (making it a Faraday
cage) which prevents signal penetration that does not violate signal
jamming laws.
Trains, particularly those involving long-distance services, often offer a
"quiet car" where phone use is prohibited, much like the designated
non-smoking car in the past. However many users tend to ignore this as it is
rarely enforced, especially if the other cars are crowded and they have no
choice but to go in the "quiet car". Mobile phone use on aircraft is also
prohibited and many airlines claim in their in-plane announcements that this
prohibition is due to possible interference with aircraft radio communications.
Shut-off mobile phones do not interfere with aircraft avionics. The nuisance of
telephones on while aeroplanes take off and land, is that they disrupt the
ground mobile telephone networks.[citation needed]
As customers want to be connected on planes, now several airlines are
experimenting with base station and antenna systems installed to the aeroplane,
allowing low power, short-range connection of any phones aboard to remain
connected to the aircraft's base station.[citation needed] Thus,
they would not attempt connection to the ground base stations as during take
off and landing.[citation needed]
Simultaneously, airlines could offer phone services to their traveling
passengers either as full voice and data services, or initially only as SMS
text messaging and similar services. Qantas, the Australian airline, is the
first airline to run a test airplane in this configuration in the Autumn of
2007.[citation needed] Emirates
have announced plans to allow limited mobile phone usage on some flights.[citation needed]
In any case, there are inconsistencies between practices allowed by
different airlines and even on the same airline in different countries. For
example, Northwest Airlines may allow the use of mobile
phones immediately after landing on a domestic flight within the US, whereas
they may state "not until the doors are open" on an international
flight arriving in the Netherlands. In April 2007 the US Federal Communications Commission
officially grounded the idea of allowing passengers to use phones during a
flight.[14]
In a similar vein, signs are put up in UK petrol
stations prohibiting the use of mobile phones, due to possible safety
issues. Most schools in the United States have prohibited mobile phones in the
classroom, due to the large number of class disruptions that result from their
use, the potential for cheating via text messaging, and the possibility of
photographing someone without consent.[citation needed] In the
UK, possession of a mobile phone in an examination can result in immediate
disqualification from that subject or from all that student's subjects.[15]
A working group, made up of Finnish telephone companies, public transport
operators and communications authorities, have launched a campaign to remind
mobile phone users of courtesy, especially when using mass transit – what to
talk about on the phone, and how to. In particular, the campaign wants to
impact loud mobile phone usage as well as calls regarding sensitive matters.[16]
[edit] Use in disaster response
The Finnish government decided in 2005 that the fastest way to warn citizens
of disasters was the mobile phone network. In Japan, mobile phone companies
provide immediate notification of earthquakes
and other natural disasters to their customers free of
charge.[citation needed] 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.[citation needed] In Finland
rescue services suggest hikers carry mobile phones in case of emergency even
when deep in the forests beyond cellular coverage, as the radio signal of a
cellphone attempting to connect to a base station can be detected by overflying
rescue aircraft with special detection gear. Also, users in the United States
can sign up through their provider for free text messages when an AMBER Alert
goes out for a missing person in their area.
[edit] Use
by drivers
One phone in each hand
Main article: Mobile phones and driving safety
Mobile-phone use while driving is common but controversial. While few jurisdictions
have banned motorists from using mobile phones while driving outright, some
have banned or restricted drivers from using hand-held mobile phones
while exempting phones operated in a hands-free fashion. Using a
hand-held mobile phone while driving is an impediment to vehicle operation that
can increase the risk of road traffic accidents. However, some studies
have found similarly elevated accident rates among drivers using hands-free phones,
suggesting that the distraction of a telephone conversation itself is a
significant safety problem.[17]
This problem does not apply to conversations with a passenger, as
passengers can regulate the flow of conversation according to the perceived
level of danger, and also provides a second pair of eyes to spot hazards. [18]
[edit] Applications
Mobile
news services are expanding with many organizations 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[19]
and small independent news companies such as Jasmine News in Sri Lanka. Companies like Monster[20] 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,
e.g. Mobilemo.
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.
[edit] Power
Mobile phones generally obtain power from batteries which can be recharged from mains power,
a USB port or a
cigarette lighter socket in a car. Formerly, the most common form of cell 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. Cell phone manufacturers have
been experimenting with alternate power sources.
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[edit] Features
Main article: Mobile phone features
There are significant questions as to who first invented the camera phone,
as numerous other people received patents filed in the early 1990s for the
device, including David M. Britz of AT&T Research in March of 1994 and Phillipe
Kahn, who claims to have first invented it in 1997.[citation needed] The camera
phone now holds 85% of the mobile phone market[citation needed]. Mobile
phones often have features beyond sending text messages and making voice calls,
including Internet browsing, music (MP3) playback, memo recording, personal organizer functions, e-mail, instant
messaging, built-in cameras and camcorders, ringtones,
games, radio, Push-to-Talk (PTT), infrared and Bluetooth connectivity,
call registers, ability to watch streaming video or download video for later
viewing, video calling and serve 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 (e.g. Final Fantasy Agito).[citation needed]
[edit] Tariff
models
See
also: GSM services#Voice charges
When cellular telecoms services were launched, phones and calls were very
expensive and early mobile operators (carriers) decided to charge for all air
time consumed by the mobile phone user. This resulted in the concept of
charging callers for outbound calls and also for receiving calls. As mobile
phone call charges diminished and phone adoption rates skyrocketed, more modern
operators decided not to charge for incoming calls. Thus some markets have
"Receiving Party Pays" models (or, more correctly, "Mobile
Party Pays"), in which both outbound and received calls are charged,
and other markets have "Calling Party Pays" models, by which only
making calls produces costs, and receiving calls is free. An exception to this
are international
roaming tariffs, by which receiving calls are normally also charged.[citation needed]
The European market adopted a "Calling Party Pays" model
throughout the GSM environment and soon various other GSM markets also started
to emulate this model. As Receiving Party Pays systems have the undesired
effect of phone owners keeping their phones turned off to avoid receiving
unwanted calls, the total voice usage rates (and profits) in Calling Party Pays
countries outperform those in Receiving Party Pays countries. Consequently,
most countries previously with Receiving Party Pays models have either
abandoned them or employed alternative marketing methods, such as massive voice
call buckets, to avoid the problem of phone users keeping phones turned off.[citation needed]
In most countries today, including European
Union nations, United Arab Emirates, Kazakhstan,
Turkey, New Zealand,
Korea, Japan, Pakistan, Australia, Brazil, Chile, Colombia, India,[21] Maldives, Malaysia, Peru, South Africa, Israel, Lebanon and Jordan the person
receiving a mobile phone call pays nothing. However, in Hong Kong, Canada, and the United
States, one can be charged per minute. In the United States, a few carriers
are beginning to offer unlimited received phone calls. For the Chinese mainland,
it was reported that both of its two operators will adopt the caller-pays
approach as early as January 2007.[21]
[edit] Developing countries
In some developing countries with little telephone infrastructure,
the mobile telephone is the telephony giving poor people access to medical and
legal services. Cell phone use in developing countries has quadrupled in the
last decade.[22].
The rise of cell phone technology in developing countries is often cited as an
example of the leapfrog effect. In many remote regions in the
third world went literally from having no telecommunications infrastructure to
having satellite based communications systems.
[edit] Forensics and evidence
Law enforcement globally rely heavily upon mobile telephone evidence, to the
extent that in the EU the "communications of every mobile telephone user
are recorded"[23].
The concerns over terrorism and terrorist use of technology prompted an
inquiry by the British House of Commons Home Affairs Select Committee into
the use of evidence from mobile telephone devices, prompting leading mobile
telephone forensic specialists to identify forensic techniques available in
this area.[24]
NIST have published guidelines and procedures for the preservation,
acquisition, examination, analysis, and reporting of digital information
present on cell phones can be found under the NIST Publication SP800-101.[25]
An example of criminal investigations using mobile phones is the initial
location and ultimate identification of the terrorists of the 2004 Madrid train bombings. In the
attacks, mobile phones had been used to detonate the bombs. However, one of the
bombs failed to detonate, and the SIM card in the corresponding mobile
phone gave the first serious lead about the terrorists to investigators. By
tracking the whereabouts of the SIM card and correlating other mobile phones
that had been registered in those areas, police were able to locate the
terrorists.[citation needed]
[edit] Human health impacts
Main article: Mobile phone radiation and health
Since the introduction of mobile phones, concerns have been raised about the
potential health impacts from regular use.[26]
As mobile phone penetrations grew past fixed landline penetration levels in
1998 in Finland and from 1999 in Sweden, Denmark and Norway, the Scandinavian
health authorities have run continuous long term studies of effects of mobile
phone radiation effects to humans, and in particular children. Numerous studies
have reported and most studies consistently report no significant relationship
between mobile phone use and health. Studies from the Institute of Cancer
Research, National Cancer Institute and researchers at the Danish Institute of
Cancer Epidemiology in Copenhagen for example showed no link between mobile
phone use and cancer.[27][28]
The Danish study only covered analog mobile phone usage up through 1995, and
subjects who started mobile phone usage after 1995 were counted as non-users in
the study.[29]
The health concerns have grown as mobile phone penetration rates throughout
Europe reached 80%–90% levels earlier in this decade and prolonged exposure
studies have been carried out in almost all European countries again most
reporting no effect, and the most alarming studies only reporting a possible
effect. However, a study by the International Agency for
Research on Cancer of 4,500 users found a statistically significant link
between tumor frequency and mobile phone use.[30]
The link between cellphones and low sperm quality suggests that the radiation
emitting from mobile phones may be potentially dangerous and should be
considered as such.[31]
[edit] Environmental impacts
Like all high structures, cellular antenna masts pose a hazard to low flying
aircraft.
Towers over a certain height or towers that are close to airports or heliports are
normally required to have warning lights. There have been reports that warning
lights on cellular masts, TV-towers and other high structures can attract and
confuse birds. US authorities estimate
that millions of birds are killed near communication towers in the country each
year.[32]
An example of the way mobile phones and mobile networks have sometimes been
perceived as a threat is the widely reported and later discredited claim that
mobile phone masts are associated with the "Colony Collapse Disorder" (CCD) which
has reduced bee hive numbers by up to 75% in many areas, especially near cities
in the US. The Independent newspaper cited a scientific study claiming it
provided evidence for the theory that mobile phone masts are a major cause in
the collapse of bee populations, with controlled experiments demonstrating a
rapid and catastrophic effect on individual hives near masts.[33]
Mobile phones were in fact not covered in the study, and the original
researchers have since emphatically disavowed any connection between their
research, mobile phones, and CCD, specifically indicating that the Independent
article had misinterpreted their results and created "a horror story".[34][35][36] While the initial claim of damage to bees was widely
reported, the corrections to the story were almost non-existent in the media.
[edit] Technology
See
also: Cellular frequencies
Mobile phone tower
Cell Phone tower located in Lynnwood,
WA.
Mobile phones and the network they operate under vary significantly from
provider to provider, and country to country. However, all of them communicate
through electromagnetic radio waves 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 not more than
8 to 13 km (approximately 5 to 8 miles) away. When the mobile 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
various cell sites during calls, or while waiting (idle) between calls it will reselect 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. Many of these sites are
camouflaged to blend with existing environments, particularly in scenic areas.
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. The
technologies are grouped by generation. The first-generation systems started in
1979 with Japan, are all analog and include AMPS and NMT. Second-generation
systems, started in 1991 in Finland, are all digital and include GSM, CDMA and
TDMA. Third-generation networks, which are still being deployed, started with
Japan in 2001, are all digital, and offer high-speed data access in addition to
voice services and include W-CDMA (known also as UMTS), and CDMA2000
EV-DO. China will launch a third 3G technlogy on the TD-SCDMA standard. Each
network operator has a unique radio
frequency band.[citation needed]
[edit] Books about mobile communication
Since 2002, many books have been written on the social impact of mobile
phones:
- Agar, Jon, Constant
Touch: A Global History of the Mobile Phone, 2004 ISBN
1840465417
- Ahonen, Tomi, m-Profits:
Making Money with 3G Services, 2002, ISBN
0-470-84775-1
- Ahonen, Kasper and Melkko,
3G Marketing 2004, ISBN
0-470-85100-7
- Glotz, Peter &
Bertsch, Stefan, eds. Thumb Culture: The Meaning of Mobile Phones for Society,
2005
- Katz, James E. &
Aakhus, Mark, eds. Perpetual Contact: Mobile Communication, Private
Talk, Public Performance, 2002
- Kavoori, Anandam &
Arceneaux, Noah, eds. The Cell Phone Reader: Essays in Social
Transformation, 2006
- Levinson,
Paul, Cellphone: The Story of the World's Most Mobile Medium, and
How It Has Transformed Everything!, 2004 ISBN
1-4039-6041-0
- Ling, Rich, The Mobile Connection: the Cell Phone's
Impact on Society, 2004 ISBN
1558609369
- Ling, Rich and Pedersen,
Per, eds. Mobile Communications: Re-negotiation of the Social Sphere,
2005 ISBN
1852339314
- Nyíri, Kristóf, ed. Mobile
Communication: Essays on Cognition and Community, 2003
- Nyíri, Kristóf, ed. Mobile
Learning: Essays on Philosophy, Psychology and Education, 2003
- Nyíri, Kristóf, ed. Mobile
Democracy: Essays on Society, Self and Politics, 2003
- Nyíri, Kristóf, ed. A
Sense of Place: The Global and the Local in Mobile Communication, 2005
- Nyíri, Kristóf, ed. Mobile
Understanding: The Epistemology of Ubiquitous Communication, 2006
- Plant,
Dr. Sadie, on
the mobile – the effects of mobile telephones on social and individual
life, 2001
- Rheingold, Howard, Smart Mobs: The Next
Social Revolution, 2002 ISBN
0738208612
[edit] Terminology
[edit] Related non-mobile-phone systems
Cordless telephone (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. Increasingly, with wireless local loop technologies, namely DECT, the distinction
is blurred.
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. Also, they may require the assistance of a human operator to set
up a PSTN phone
call.
[edit] Terms in various countries
Further information: Mobile phone terms across the world
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