History of mobile phones
The history of mobile phones begins with early efforts to develop radio telephone technology and from two-way radios in vehicles and continues through emergence of modern mobile phonesassociated services. and
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 mobile radio devices have been available since 1973. Mobile phone history is often divided into generations (first, second, third and so on) to mark significant step changes in capabilities as the technology improved over the years.
Pioneers of radio telephony
In 1908, U.S. Patent 887,357 for a wireless telephone was issued to Nathan B. Stubblefield of Murray, Kentucky. He applied this patent to "cave radio" telephones and not directly to cellular telephony as the term is currently understood.[1]
In 1910 Lars Magnus Ericsson installed a telephone in his car, although this was not a radio telephone. While travelling across the country, he would stop at a place where telephone lines were accessible and using a pair of long electric wires he could connect to the national telephone network.[2]
In Europe, radio telephony was first used on the first-class passenger trains between Berlin and Hamburg in 1926. At the same time, radio telephony was introduced on passenger airplanes for air traffic security. Later radio telephony was introduced on a large scale in German tanks during the Second World War. After the war German police in the British zone of occupation first used disused tank telephony equipment to run the first radio patrol cars.[citation needed] In all of these cases the service was confined to specialists that were trained to use the equipment. In the early 1950s ships on the Rhine were among the first to use radio telephony with an untrained end customer as a user.
Two-way radios (known as mobile rigs) were used in vehicles such as taxicabs, police cruisers, and ambulances, but were not mobile phones because they were not normally connected to the telephone network. Users could not dial phone numbers from their vehicles. A large community of mobile radio users, known as the mobileers, popularized the technology that would eventually give way to the mobile phone. Originally, mobile two-way radios were permanently installed in vehicles, but later versions such as the so-called transportables or "bag phones" were equipped with a cigarette lighter plug so that they could also be carried, and thus could be used as either mobile or as portable two-way radios. During the early 1940s, Motorola developed a backpacked two-way radio, the Walkie-Talkie and later developed a large hand-held two-way radio for the US military. This battery powered "Handie-Talkie" (HT) was about the size of a man's forearm.
In 1946 soviet engineers G. Shapiro and I. Zaharchenko successfully tested their version of a radio mobile phone mounted inside a car. The device could connect to local telephone network with a range of up to 20 kilometers.[citation needed]
In December 1947, Douglas H. Ring and W. Rae Young, Bell Labs engineers, proposed hexagonal cells for mobile phones in vehicles.[3] Philip T. Porter, also of Bell Labs, proposed that the cell towers be at the corners of the hexagons rather than the centers and have directional antennas that would transmit/receive in three directions (see picture at right) into three adjacent hexagon cells.[4] The technology did not exist then and the frequencies had not yet been allocated. Cellular technology was undeveloped until the 1960s, when Richard H. Frenkiel and Joel S. Engel of Bell Labs developed the electronics.
During the 1950s the experiments of the pioneers started to appear as usable services across society, both commercially and culturally. In the 1954 movie Sabrina, the businessman Linus Larrabee (played by Humphrey Bogart) makes a call from the phone in the back of his limousine.
In 1957 young Soviet radio engineer Leonid Kupriyanovich from Moscow created the portable mobile phone, named after himself as LK-1 or "radiophone".[5] This true mobile phone consisted of a relatively small-sized handset equipped with an antenna and rotary dial, and communicated with a base station. Kupriyanovich's "radiophone" had 3 kilogram of total weight, could operate up to 20 or 30 kilometers, and had 20 or 30 hours of battery lifespan. LK-1 and its layout was depicted in popular Soviet magazines as Nauka i zhizn, 8, 1957, p. 49, Yuniy technik, 7, 1957, p. 43–44. Engineer Kupriyanovich patented his mobile phone in the same year 1957 (author's certificate (USSR Patent) # 115494, 1.11.1957). The base station of LK-1 (called ATR, or Automated Telephone Radiostation) could connect to local telephone network and serve several customers.
In 1958, Kupriyanovich resized his "radiophone" to "pocket" version. The weight of improved "light" handset was about 500 grams.
In 1967, each mobile phone had to stay within the cell area serviced by one base station throughout the phone call. This did not provide continuity of automatic telephone service to mobile phones moving through several cell areas.
In 1969, a patent for a wireless phone using an acoustic coupler for incoming calls was issued in US Patent Number 3,449,750 to George Sweigert of Euclid, Ohio on June 10, 1969. Dialing a number for outgoing calls was not provided.
The concepts of frequency reuse and handoff, as well as a number of other concepts that formed the basis of modern cell phone technology, were described in the 1970s. In 1970 Amos E. Joel, Jr., another Bell Labs engineer,[6] invented an automatic "call handoff" system to allow mobile phones to move through several cell areas during a single conversation without loss of conversation. Also Fluhr and Nussbaum,[7] Hachenburg et al.[8] , and U.S. Patent 4,152,647, issued May 1, 1979 to Charles A. Gladden and Martin H. Parelman, both of Las Vegas, Nevada and assigned by them to the United States Government.
Emergence of commercial mobile phone services
In 1956, the first fully automatic mobile phone system, called MTA (Mobile Telephone system A), was developed by Ericsson and commercially released in Sweden. This was the first system that did not require any kind of manual control in base stations, but had the disadvantage of a phone weight of 40 kg (90 lb). MTB, an upgraded version with transistors, weighing 9 kg (20 lb), was introduced in 1965 and used DTMF signaling. It had 150 customers in the beginning and 600 when it shut down in 1983.
The first person to have a mobile phone in the United Kingdom was reputedly Prince Philip, who had a system fitted into the trunk of his Aston Martin in 1957. The Prince could make phone calls to the Queen while driving, which was thought to be quite amazing at the time. The Duke of Gloucester heard about the mobile phone and tried to obtain one, but the Post Office denied his request. They were prepared to indulge the husband of Her Majesty, but nobody else, as the system used an entire dedicated radio frequency.
In 1958 the USSR also began to deploy the "Altay" national civil mobile phone service specially for motorists.[9] The newly-developed mobile telephone system was based on Soviet MRT-1327 standard. The main developers of the Altay system were the Voronezh Science Research Institute of Communications (VNIIS) and the State Specialized Project Institute (GSPI). In 1963 this service started in Moscow, and in 1970 the Altay service already was deployed in 30 cities of the USSR. The last upgraded versions of the Altay system are still in use in some places of Russia as a trunking system.
In 1959 a private telephone company located in Brewster, Kansas, USA, the S&T Telephone Company, (still in business today) with the use of Motorola Radio Telephone equipment and a private tower facility, offered to the public mobile telephone services in that local area of NW Kansas. This system was a direct dial up service through their local switchboard, and was installed in many private vehicles including grain combines, trucks, and automobiles. For some as yet unknown reason, the system after being placed online and operated for a very brief time period was shut down. The management of the company was immediately changed, and the fully operable system and related equipment was immediately dismantled in early 1960, not to be seen again.
In 1960, the world’s first partly automatic car phone system Mobile System A (MTA)|MTArotary dial. Calling from the car was fully automatic, while calling to it required an operator. The person who wanted to call a mobile phone had to know which base station the mobile phone was covered by. The system was developed by Sture Laurén and other engineers at Televerket network operator. Ericsson provided the switchboard while Svenska Radioaktiebolaget (SRA) owned by Ericsson and Marconi provided the telephones and base station equipment. MTA phones were consisted of vacuum tubes and relays, and had a weight of 40 kg. In 1962, a more modern version called Mobile System B (MTB) was launched, which was a push-button telephone, and which used transistors in order to enhance the telephone’s calling capacity and improve its operational reliability. In 1971 the MTD version was launched, opening for several different brands of equipment and gaining commercial success.[10][11] was launched in Sweden. With MTA, calls could be made and received in the car to/from the public telephone network, and the car phone could be paged. The phone number was dialed using a
In 1966, Bulgaria presented the pocket mobile automatic phone RAT-0,5 combined with a base station RATZ-10 (RATC-10) on Interorgtechnika-66 international exhibition. One base station, connected to one telephone wire line, could serve up to six customers.
In December 1971, AT&T submitted a proposal for cellular service to the Federal Communications Commission (FCC). After years of hearings, the FCC approved the proposal in 1982 for Advanced Mobile Phone System (AMPS) and allocated frequencies in the 824–894 MHz band.[12] Analog AMPS was superseded by Digital AMPS in 1990.
One of the first successful public commercial mobile phone networks was the ARP network in Finland, launched in 1971. Posthumously, ARP is sometimes viewed as a zero generation (0G) cellular network, being slightly above previous proprietary and limited coverage networks.
The origin of the modern cell phone can be traced back to the year 1973 when Motorola invented the first cellular portable telephone to be commercialised, known as Motorola DynaTAC 8000X. Martin Cooper, a Motorola researcher and executive is considered to be the inventor of this mobile phone for use in a non-vehicle setting. There was a long race between Motorola and Bell Labs to produce the first such portable mobile phone. Cooper is the first inventor named on "Radio telephone system" filed on October 17, 1973 with the US Patent Office and later issued as US Patent 3,906,166.[13] Other named contributors on the patent included Cooper's boss, John F. Mitchell, Motorola's chief of portable communication products, who successfully pushed Motorola to develop wireless communication products that would be small enough to use outside the home, office or automobile and participated in the design of the cellular phone.[14][15] Using a modern, if somewhat heavy portable handset, Cooper made the first cellular phone call on a hand-held mobile phone on April 3, 1973 to his rival, Dr. Joel S. Engel of Bell Labs.[16].
Vodafone made the UK's first mobile call at a few minutes past midnight on 1 January 1985.[17]
First generation: Cellular networks
The main technological development that distinguished the First Generation mobile phones from the previous generation was the use of multiple cell sites, and the ability to transfer calls from one site to the next as the user travelled between cells during a conversation. The first commercially automated cellular network (the 1G generation) was launched in Japan by NTT in 1979. The initial launch network covered the full metropolitan area of Tokyo's over 20 million inhabitants with a cellular network of 23 base stations. Within five years, the NTT network had been expanded to cover the whole population of Japan and became the first nation-wide 1G network.
The second launch of 1G networks was the simultaneous launch of the Nordic Mobile TelephoneDenmark, Finland, Norway and Sweden in 1981.[18]. NMT was the first mobile phone network featuring international roaming. The Swedish electrical engineer Östen Mäkitalo[19][20] (NMT) system in started to work on this vision in 1966, and is considered as the father of the NMT system and some consider him also the father of the cellular phone.
Several countries were among the earliest to launch 1G networks in the early 1980s including the UK, Mexico and Canada. The first 1G network launched in the USA was Chicago based Ameritech in 1983 using the famous first hand-held mobile phone Motorola DynaTAC. In 1984, Bell Labs developed modern commercial cellular technology (based, to a large extent, on the Gladden, Parelman Patent), which employed multiple, centrally controlled base stations (cell sites), each providing service to a small area (a cell). The cell sites would be set up such that cells partially overlapped. In a cellular system, a signal between a base station (cell site) and a terminal (phone) only need be strong enough to reach between the two, so the same channel can be used simultaneously for separate conversations in different cells.
The first NMT installations as well as the First AMPS installations were based on the EricssonAXE digital exchange nodes.
Cellular systems required several leaps of technology, including handover, which allowed a conversation to continue as a mobile phone traveled from cell to cell. This system included variable transmission power in both the base stations and the telephones (controlled by the base stations), which allowed range and cell size to vary. As the system expanded and neared capacity, the ability to reduce transmission power allowed new cells to be added, resulting in more, smaller cells and thus more capacity. The evidence of this growth can still be seen in the many older, tall cell site towers with no antennae on the upper parts of their towers. These sites originally created large cells, and so had their antennae mounted atop high towers; the towers were designed so that as the system expanded—and cell sizes shrank—the antennae could be lowered on their original masts to reduce range.
[edit] Second generation: Digital networks
In the 1990s, the 'second generation' (2G) mobile phone systems emerged, primarily using the GSM standard. These 2G phone systems differed from the previous generation in their use of digital transmission instead of analog transmission, and also by the introduction of advanced and fast phone-to-network signaling. The rise in mobile phone usage as a result of 2G was explosive and this era also saw the advent of prepaid mobile phones
In 1991 the first GSM network (Radiolinja) opened in Finland. In general the frequencies used by 2G systems in Europe were higher than those in America, though with some overlap. For example, the 900 MHz frequency range was used for both 1G and 2G systems in Europe, so the 1G systems were rapidly closed down to make space for the 2G systems. In America the IS-54AMPS and displaced some of the existing analog channels. standard was deployed in the same band as
Coinciding with the introduction of 2G systems was a trend away from the larger "brickle" phones toward tiny 100–200g hand-held devices, which soon became the norm. This change was possible through technological improvements such as more advanced batteries and more energy-efficient electronics, but also was largely related to the higher density of cellular sites caused by increasing usage levels. This decreased the demand for high transmission powers to reach distant towers for customers to be satisfied.
The second generation introduced a new variant to communication, as SMS text messaging became possible, initially on GSM networks and eventually on all digital networks. The first machine-generated SMS message was sent in the UK on 3 December 1992. The first person-to-person SMS text message was sent in Finland in 1993. Soon SMS became the communication method of preference for the youth. Today in many advanced markets the general public prefers sending text messages to placing voice calls.
2G also introduced the ability to access media content on mobile phones, when Radiolinja (now Elisa) in Finland introduced the downloadable ring tone as paid content. Finland was also the first country where advertising appeared on the mobile phone when a free daily news headline service on SMS text messaging was launched in 2000, sponsored by advertising.
The first data services appeared on mobile phones starting with person-to-person SMS text messaging in Finland in 1993. First trial payments using a mobile phone to pay for a Coca Cola vending machine were set in Finland in 1998. The first commercial payments were mobile parking trialled in Sweden but first commercially launched in Norway in 1999. The first commercial payment system to mimic banks and credit cards was launched in the Philippines in 1999 simultaneously by mobile operators Globe and Smart. The first content sold to mobile phones was the ringing tone, first launched in 1998 in Finland. The first full internet service on mobile phones was introduced by NTT DoCoMo in Japan in 1999.
Third generation: High speed IP data networks
As the use of 2G phones became more widespread and people began to utilise mobile phones in their daily lives, it became clear that demand for data services (such as access to the internet) was growing. Furthermore, if the experience from fixed broadband services was anything to go by, there would also be a demand for ever greater data speeds. The 2G technology was nowhere near up to the job, so the industry began to work on the next generation of technology known as 3G. The main technological difference that distinguishes 3G technology from 2G technology is the use of packet switching rather than circuit switching for data transmission[21]. In addition, the standardization process focused on requirements more than technology (2 Mbit/s maximum data rate indoors, 384 kbit/s outdoors, for example).
Inevitably this led to many competing standards with different contenders pushing their own technologies, and the vision of a single unified worldwide standard looked far from reality. The standard 2G CDMA networks became 3G compliant with the adoption of Revision A to EV-DO, which made several additions to the protocol whilst retaining backwards compatibility:
- the introduction of several new forward link data rates that increase the maximum burst rate from 2.45 Mbit/s to 3.1 Mbit/s.
- protocols that would decrease connection establishment time.
- the ability for more than one mobile to share the same time slot.
- the introduction of QoS flags.
All these were put in place to allow for low latency, low bit rate communications such as VoIP.[22]
The first pre-commercial trial network with 3G was launched by NTT DoCoMo in Japan in the Tokyo region in May 2001. NTT DoCoMo launched the first commercial 3G network on October 1, 2001, using the WCDMA technology. In 2002 the first 3G networks on the rival CDMA2000 1xEV-DO technology were launched by SK Telecom and KTF in South Korea, and Monet in the USA. Monet has since gone bankrupt. By the end of 2002, the second WCDMA network was launched in Japan by Vodafone KK (now Softbank). European launches of 3G were in Italy and the UK by the Three/Hutchison group, on WCDMA. 2003 saw a further 8 commercial launches of 3G, six more on WCDMA and two more on the EV-DO standard.
During the development of 3G systems, 2.5G systems such as CDMA2000 1x and GPRS were developed as extensions to existing 2G networks. These provide some of the features of 3G without fulfilling the promised high data rates or full range of multimedia services. CDMA2000-1X delivers theoretical maximum data speeds of up to 307 kbit/s. Just beyond these is the EDGE system which in theory covers the requirements for 3G system, but is so narrowly above these that any practical system would be sure to fall short.
The high connection speeds of 3G technology enabled a transformation in the industry: for the first time, media streaming of radio (and even television) content to 3G handsets became possible [2], with companies such as RealNetworks [3] and Disney [4] among the early pioneers in this type of offering.
In the mid 2000s an evolution of 3G technology begun to be implemented, namely High-Speed Downlink Packet Access (HSDPA). It is an enhanced 3G (third generation) mobile telephonycommunications protocol in the High-Speed Packet Access (HSPA) family, also coined 3.5G, 3G+ or turbo 3G, which allows networks based on Universal Mobile Telecommunications SystemMbit/s. Further speed increases are available with HSPA+, which provides speeds of up to 42 Mbit/s downlink and 84 Mbit/s with Release 9 of the 3GPP standards. (UMTS) to have higher data transfer speeds and capacity. Current HSDPA deployments support down-link speeds of 1.8, 3.6, 7.2 and 14.0
By the end of 2007 there were 295 Million subscribers on 3G networks worldwide, which reflected 9% of the total worldwide subscriber base. About two thirds of these were on the WCDMA standard and one third on the EV-DO standard. The 3G telecoms services generated over 120 Billion dollars of revenues during 2007 and at many markets the majority of new phones activated were 3G phones. In Japan and South Korea the market no longer supplies phones of the second generation. Earlier in the decade there were doubts about whether 3G might happen, and also whether 3G might become a commercial success. By the end of 2007 it had become clear that 3G was a reality and was clearly on the path to become a profitable venture.
Growth of mobile broadband and the emergence of 4G
Although mobile phones had long had the ability to access data networks such as the Internet, it was not until the widespread availability of good quality 3G coverage in the mid 2000s that specialised devices appeared to access the mobile internet. The first such devices, known as "dongles", plugged directly into a computer through the USB port. Another new class of device appeared subsequently, the so-called "compact wireless router" such as the Novatel MiFi, which makes 3G internet connectivity available to multiple computers simultaneously over Wi-Fi, rather than just to a single computer via a USB plug-in.
Such devices became especially popular for use with laptop computers due to the added portability they bestow. Consequently, some computer manufacturers started to embed the mobile data function directly into the laptop so a dongle or MiFi wasn't needed. Instead, the SIM card could be inserted directly into the device itself to access the mobile data services. Such 3G-capable laptops became commonly known as "netbooks". Other types of data-aware devices followed in the netbooks' footsteps. By the beginning of 2010, E-readers, such as the AmazonKindle and the Nook from Barnes & Noble, had already become available with embedded wireless internet, and Apple Computer had announced plans for embedded wireless internet on its iPad tablet devices beginning that Fall.
By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications like streaming media[23]. Consequently, the industry began looking to data-optimized 4th-generation technologies, with the promise of speed improvements up to 10-fold over existing 3G technologies. The first two commercially available technologies billed as 4G were the WiMAX standard (offered in the U.S. by Sprint) and the LTETeliaSonera. standard, first offered in Scandinavia by
One of the main ways in which 4G differed technologically from 3G was in its elimination of circuit switching, instead employing an all-IP network. Thus, 4G ushered in a treatment of voice calls just like any other type of streaming audio media, utilizing packet switching over internet, LAN or WAN networks via VoIP.[24]
Patents
- U.S. Patent 3,663,762: Cellular Mobile Communication System — Amos Edward Joel (Bell Labs), filed December 21, 1970, issued May 16, 1972
- U.S. Patent 3,906,166: Radio Telephone System (Dyna-Tac) — Martin Cooper et al. (Motorola), filed October 17, 1973, issued September 16, 1975
- U.S. Patent 4,144,411: Cellular Radiotelephone System for Different Cell Sizes — Richard H. Frenkiel (Bell Labs), filed September 22, 1976, issued March 13, 1979
- U.S. Patent 4,399,555: Cellular Mobile Radiotelephone System — Verne MacDonald, Philip Porter, Rae Young, (Bell Labs) filed April 28, 1980, issued August 16, 1983
- U.S. Patent 5,129,098: Radio telephone using received signal strength in controlling transmission power — Andrew McGirr, Barry Cassidy (Novatel), filed September 24, 1990, issued July 7, 1992
- U.S. Patent 5,265,158: Construction of a stand alone portable telephone unit — Jouko Tattari (Nokia), filed May 11, 1992, issued November 23, 1993
- U.S. Patent 5,722,067: Security cellular telecommunications system — Douglas Fougnies et al. (Freedom Wireless), filed December 1994, issued February 24, 1998
- U.S. Patent 5,826,185: Cellular phone system wherein the air time use is predetermined — Andrew Wise et al. (Banana Communications), filed November 1994, issued October 20, 1998
- U.S. Patent 5,841,856: Hands-free telephone set — Yoshiyuki Ide (NEC), filed May 21, 1997, issued November 24, 1998
- U.S. Patent 7,324,480: Mobile communication apparatus and method including base station and mobile station having multi-antenna: Per-User Unitary Rate Control (PU2RC) — James S. Kim, Kwangbok Lee, Kiho Kim and Changsoon Park, filed July 10, 2003, issued January 29, 2008
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