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
Tuesday, November 20, 2007
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).
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.
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.
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.
Use by drivers
Use by drivers
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.
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.
Use in disaster response
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.
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.
Etiquette
Etiquette
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.
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.
Culture and customs
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
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
Subscriptions
Subscriptions
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 onthe WCDMA (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.
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 onthe WCDMA (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.
Manufacturers
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.
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.
Mobile phone
History
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.
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.
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