I-mode
NTT DoCoMo's i-mode is a mobile internet service popular in Japan. Unlike Wireless Application Protocol, i-mode encompasses a wider variety of internet standards, including web access, e-mail, the packet-switched network that delivers the data. I-mode users have access to various services such as e-mail, sports results, weather forecast, financial services, ticket booking. Content is provided by specialized services from the mobile carrier, which allows them to have tighter control over billing. Like WAP, i-mode delivers only those services that are converted for the service, or are converted through gateways. In contrast with the Wireless Application Protocol standard, which used Wireless Markup Language on top of a protocol stack for wireless handheld devices, i-mode borrows from DoCoMo proprietary protocols ALP and TLP, as well as fixed Internet data formats such as C-HTML, a subset of the HTML language designed by DoCoMo. C-HTML was designed for small devices with hardware restrictions such as such lower memory, low-power CPUs with limited or no storage capabilities, small monochrome display screens, single-character fonts and limited input methods.
As a simpler form of HTML, C-HTML does not support tables, image maps, multiple fonts and styling of fonts, background colors and images, frames, or style sheets, is limited to a monochromatic display.i-mode phones have a special i-mode button for the user to access the start menu. There are more than 12,000 official sites and around 100,000 or more unofficial i-mode sites, which are not linked to DoCoMo's i-mode portal page and DoCoMo's billing services. NTT DoCoMo supervises the content and operations of all official i-mode sites, most of which are commercial; these official sites are accessed through DoCoMo's i-mode menu but in many cases official sites can be accessed from mobile phones by typing the URL or through the use of QR code. An i-mode user pays for both received data. There are services to avoid unsolicited e-mails; the basic monthly charge is on the order of JPY ¥200 - ¥300 for i-mode not including the data transfer charges, with additional charges on a monthly subscription basis for premium services.
A variety of discount plans exist, for example family discount and flat packet plans for unlimited transfer of data at a fixed monthly charge. I-mode was launched in Japan on 22 February 1999; the content planning and service design team was led by Mari Matsunaga, while Takeshi Natsuno was responsible for the business development. Top executive Keiichi Enoki oversaw the overall development. A few months after DoCoMo launched i-mode in February 1999, DoCoMo's competitors launched similar mobile data services: KDDI launched EZweb, J-Phone launched J-Sky. Vodafone acquired J-Phone including J-Sky, renaming the service Vodafone live!, although this was different from Vodafone live! in Europe and other markets. In addition, Vodafone KK was acquired by SoftBank, an operator of Yahoo! Japan changed the name to SoftBank Mobile; as of June 2006, the mobile data services I-Mode, EZweb, J-Sky, had over 80 million subscribers in Japan. Since 2003, i-mode center is called CiRCUS, which consists of 400 NEC NX7000 HP-UX servers and occupies 4,600 m² floor space in DoCoMo's Kawasaki office.
The operation support system is called CARNiVAL, hosted in the Sanno Park Tower. I-mode usage in Japan peaked around 2008; as of 2016, it is still available, but has been eclipsed by the internet features in 3G, 4G, WiFi enabled smartphones. Seeing the tremendous success of i-mode in Japan, many operators in Europe and Australia sought to license the service through partnership with DoCoMo. Takeshi Natsuno was behind the expansion of i-mode to 17 countries worldwide. Kamel Maamria, a partner with the Boston Consulting Group and, supporting Mr. Natsuno is thought to have had a major role in the expansion of the first Japanese service outside Japan. I-mode showed fast take-up in the various countries where it was launched which led to more operators seeking to launch i-mode in their markets with the footprint reaching a total of 17 markets worldwide. While the i-mode service was an exceptional service which positioned DoCoMo as the global leader in value add services, another key success factor for i-mode was the Japanese smartphone makers who developed state of the art handsets to support i-mode.
As i-mode was exported to the rest of the world and other major handset vendors who controlled the markets at the time, refused at first to support i-mode by developing handsets which support the i-mode service. The operators who decided to launch i-mode had to rely on Japanese vendors who had no experience in international markets; as i-mode showed success in these markets, some vendors started customizing some of their handsets to support i-mode, the support was only partial and came late in time. While the service was successful during the first years after launch, the lack of adequate handsets and the emergence of new handsets from new vendors which supported new Internet services on one hand, a change of leadership of i-mode in Docomo, lead to a number of operators to migrate or integrate i-mode into new mobile Internet services; these efforts were unsuccessful, i-mode never became popular outside of Japan.i-mode was launched in the following countries: Australia, Belgium Bulgaria France Germany Greece Hong Kong Israel Ireland Italy Netherlands Russia Romania Singapore Spain
Telecommunication
Telecommunication is the transmission of signs, messages, writings and sounds or information of any nature by wire, optical or other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology, it is transmitted either electrically over physical media, such as cables, or via electromagnetic radiation. Such transmission paths are divided into communication channels which afford the advantages of multiplexing. Since the Latin term communicatio is considered the social process of information exchange, the term telecommunications is used in its plural form because it involves many different technologies. Early means of communicating over a distance included visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, optical heliographs. Other examples of pre-modern long-distance communication included audio messages such as coded drumbeats, lung-blown horns, loud whistles. 20th- and 21st-century technologies for long-distance communication involve electrical and electromagnetic technologies, such as telegraph and teleprinter, radio, microwave transmission, fiber optics, communications satellites.
A revolution in wireless communication began in the first decade of the 20th century with the pioneering developments in radio communications by Guglielmo Marconi, who won the Nobel Prize in Physics in 1909, other notable pioneering inventors and developers in the field of electrical and electronic telecommunications. These included Charles Wheatstone and Samuel Morse, Alexander Graham Bell, Edwin Armstrong and Lee de Forest, as well as Vladimir K. Zworykin, John Logie Baird and Philo Farnsworth; the word telecommunication is a compound of the Greek prefix tele, meaning distant, far off, or afar, the Latin communicare, meaning to share. Its modern use is adapted from the French, because its written use was recorded in 1904 by the French engineer and novelist Édouard Estaunié. Communication was first used as an English word in the late 14th century, it comes from Old French comunicacion, from Latin communicationem, noun of action from past participle stem of communicare "to share, divide out.
Homing pigeons have been used throughout history by different cultures. Pigeon post had Persian roots, was used by the Romans to aid their military. Frontinus said; the Greeks conveyed the names of the victors at the Olympic Games to various cities using homing pigeons. In the early 19th century, the Dutch government used the system in Sumatra, and in 1849, Paul Julius Reuter started a pigeon service to fly stock prices between Aachen and Brussels, a service that operated for a year until the gap in the telegraph link was closed. In the Middle Ages, chains of beacons were used on hilltops as a means of relaying a signal. Beacon chains suffered the drawback that they could only pass a single bit of information, so the meaning of the message such as "the enemy has been sighted" had to be agreed upon in advance. One notable instance of their use was during the Spanish Armada, when a beacon chain relayed a signal from Plymouth to London. In 1792, Claude Chappe, a French engineer, built the first fixed visual telegraphy system between Lille and Paris.
However semaphore suffered from the need for skilled operators and expensive towers at intervals of ten to thirty kilometres. As a result of competition from the electrical telegraph, the last commercial line was abandoned in 1880. On 25 July 1837 the first commercial electrical telegraph was demonstrated by English inventor Sir William Fothergill Cooke, English scientist Sir Charles Wheatstone. Both inventors viewed their device as "an improvement to the electromagnetic telegraph" not as a new device. Samuel Morse independently developed a version of the electrical telegraph that he unsuccessfully demonstrated on 2 September 1837, his code was an important advance over Wheatstone's signaling method. The first transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecommunication for the first time; the conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849.
However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London. Starting in 1894, Italian inventor Guglielmo Marconi began developing a wireless communication using the newly discovered phenomenon of radio waves, showing by 1901 that they could be transmitted across the Atlantic Ocean; this was the start of wireless telegraphy by radio. Voice and music had little early success. World War I accelerated the development of radio for military communications. After the war, commercial radio AM broadcasting began in the 1920s and became an important mass medium for entertainment and news. World War II again accelerated development of radio for the wartime purposes of aircraft and land communication, radio navigation and radar. Development of stereo FM broadcasting of radio
Nordic Mobile Telephone
NMT is the first automatic cellular phone system. It was specified by Nordic telecommunications administrations and opened for service on 1 October 1981 as a response to the increasing congestion and heavy requirements of the manual mobile phone networks: ARP in Finland, MTD in Sweden and Denmark, OLT in Norway. NMT is based on analogue technology and two variants exist: NMT-450 and NMT-900; the numbers indicate. NMT-900 carries more channels than the older NMT-450 network; the NMT specifications were free and open, allowing many companies to produce NMT hardware and pushing prices down. The success of NMT was important to Ericsson. First Danish implementers were Storno and AP. Initial NMT phones were designed to mount in the trunk of a car, with a keyboard/display unit at the driver's seat. "Portable" versions existed, though they were still bulky, with battery life still being a big problem. Models such as Benefon's were as small as 100 mm and weighed only about 100 grams; the NMT network was opened in Sweden and Norway in 1981, in Denmark and Finland in 1982.
Iceland joined in 1986. However, Ericsson introduced the first commercial service in Saudi Arabia on 1 September 1981 to 1,200 users, as a pilot test project, one month before they did the same in Sweden. By 1985 the network had grown to 110,000 subscribers in Scandinavia and Finland, 63,300 in Norway alone, which made it the world's largest mobile network at the time; the NMT network has been used in the Nordic countries, Baltic countries, Netherlands, Poland, Romania, Czech Republic, Slovenia, Turkey, Bosnia, Ukraine and in Asia. The introduction of digital mobile networks such as GSM has reduced the popularity of NMT and the Nordic countries have suspended their NMT networks. In Estonia the NMT network was shut down in December 2000. In Finland TeliaSonera's NMT network was suspended on 31 December 2002. Norway's last NMT network was suspended on 31 December 2004. Sweden's TeliaSonera NMT network was suspended on 31 December 2007; the NMT network however has one big advantage over GSM, the range.
In Iceland, the GSM network reaches 98% of the country's population but only a small proportion of its land area. The NMT system however reaches most of the country and a lot of the surrounding waters, thus the network was popular with fishermen and those traveling in the vast empty mainland. In Iceland the NMT service was stopped on 1 September 2010. In Denmark and Sweden the NMT-450 frequencies have been auctioned off to Swedish Nordisk Mobiltelefon which became Ice.net and renamed to Net 1 that built a digital network using CDMA 450. During 2015, the network has been migrated to 4G. Permission for TeliaSonera to continue operation of the NMT-450 frequencies ended on 31 December 2007. In Russia Uralwestcom shut down their NMT network on 1 September 2006 and Sibirtelecom on 10 January 2008. Skylink, subsidiary company of TELE2 Russia operates NMT-450 network as of 2016 in Arkhangelsk Oblast and Perm Krai; these networks are used in sparsely populated areas with long distance. License for the provision of services is valid until 2021 The cell sizes in an NMT network range from 2 km to 30 km.
With smaller ranges the network can service more simultaneous callers. NMT used full duplex transmission, allowing for simultaneous transmission of voice. Car phone versions of NMT used transmission power of up to 15 watt and 6 watt, handsets up to 1 watt. NMT had automatic switching and handover of the call built into the standard from the beginning, not the case with most preceding car phone services, such as the Finnish ARP. Additionally, the NMT standard specified billing as well as international roaming. NMT voice channel is transmitted with FM-modulation and NMT signaling transfer speeds vary between 600 and 1,200 bits per second, using FFSK modulation. Signaling between the base station and the mobile station was implemented using the same RF channel, used for audio, using the 1,200 bit/s FFSK modem; this caused the periodic short noise bursts, e.g. during handover, that were uniquely characteristic to NMT sound. A disadvantage of the original NMT specification is that voice traffic was not encrypted, therefore it was possible to listen to calls using e.g. a scanner.
As a result, some scanners have had the NMT bands blocked. Versions of the NMT specifications defined optional analog scrambling, based on two-band audio frequency inversion. If both the base station and the mobile station supported scrambling, they could agree upon using it when initiating a phone call. If two users had mobile stations supporting scrambling, they could turn it on during conversation if the base stations didn't support it. In this case, audio would be scrambled all the way between the 2 mobile stations. While the scrambling method was not at all as strong as encryption of current digital phones, such as GSM or CDMA, it did prevent casual listening with scanners. Scrambling is defined in NMT Doc 450-1: System Description and NMT Doc 450-3 and 900-3: Technical Specification for the Mobile Station's Annex 26 v.1.1: Mobile Station
Osaifu-Keitai
Osaifu-Keitai "Wallet Mobile", is the de facto standard mobile payment system in Japan. Osaifu-Keitai services include electronic money, identity card, loyalty card, fare collection of public transits, or credit card; the system was developed by NTT docomo but the system is supported by other mobile phone operators. It uses Sony's Mobile FeliCa ICs. NTT docomo Group: i-mode FeliCa KDDI: EZ FeliCa SoftBank Mobile: S! FeliCa Willcom: WILLCOM IC Service FeliCa, developed by Sony, is the de facto standard technology used for Japanese smart cards. Many of these cards plan to accept it in future. Osaifu-Keitai can provide more convenient services than plastic FeliCa cards. For instance, it can automatically recharge itself via the Internet, or provide the latest information, it can be used as a ticket for an airplane or an event, by downloading an electronic ticket. Unlike plastic cards, a single Osaifu-Keitai phone may accept multiple applications, each equivalent to different cards. Osaifu-Keitai provides many functions on a single mobile phone.
Therefore, there is a great risk if the phone is broken, or stolen. Osaifu-Keitai functions without radio transmissions, so the applications can not be terminated just by closing a phone account. A user has to contact each service provider to stop all the functions. There are some phones that can lock the functions via an E-mail. Since Osaifu-Keitai can function as identity card, there is a risk for those who authenticate it. Mobile payment Electronic money FeliCa Osaifu-Keitai from NTT DoCoMo official website EZ FeliCa from au official website S! FeliCa from SoftBank Mobile official website WILLCOM IC Service from WILLCOM official website FeliCa from Sony official website
NTT Docomo
NTT Docomo Inc. is the predominant mobile phone operator in Japan. The name is an abbreviation of the phrase, "do communications over the mobile network", is from a compound word dokomo, meaning "everywhere" in Japanese. Docomo provides phone, video phone, i-mode, mail services; the company's headquarters are in the Sanno Park Tower, Nagatachō, Tokyo. Docomo was spun off from Nippon Telegraph and Telephone in August 1991 to take over the mobile cellular operations, it provides 3G W-CDMA services and 4G LTE services. Its businesses included PHS, satellite. Docomo ceased offering a PHS service on January 7, 2008. NTT Docomo is a subsidiary of Japan's incumbent telephone operator, NTT; the majority of NTT Docomo's shares are owned by NTT. While some NTT shares are publicly traded, control of the company by Japanese interests is guaranteed by the number of shares available to buyers, it provides wireless voice and data communications to subscribers in Japan. NTT Docomo is the creator of W-CDMA technology as well as mobile i-mode service.
In late 1995, Docomo CEO hired the consulting firm PricewaterhouseCoopers for strategy development, at that time worked on the first design of data services on mobile for NTT Docomo CEO. NTT Docomo has more than 53 million customers, more than half of Japan's cellular market; the company provides a wide variety of mobile multimedia services. These include i-mode which provides e-mail and internet access to over 50 million subscribers, FOMA, launched in 2001 as the world's first 3G mobile service based on W-CDMA, Xi, a 4G LTE mobile service, launched on December 24, 2010, Premium 4G, a LTE Advanced service, launched on March 27, 2015. In addition to wholly owned subsidiaries in Europe and North America, the company is expanding its global reach through strategic alliances with mobile and multimedia service providers in Asia-Pacific and Europe. NTT Docomo is listed on the Tokyo and New York stock exchanges. On April 19, 2008, it was announced that Ryuji Yamada, the current co-president of NTT Docomo, will be promoted as the president of NTT Docomo in June 2008.
Masao Nakamura will stay in NTT Docomo as a director and the senior adviser. Since October 2006, when the introduction to the service which allows the user to carry their original phone number with a new provider was made, NTT Docomo has lost many users to KDDI and SoftBank; this promotion was made in order to get more users for NTT Docomo. The company was the last major global mobile carrier to offer Apple's iPhone, which it did with the release of the iPhone 5s and 5c; this has been cited as one of the reasons for the steady stream of its customers switching for competing networks. In June 2011, the company announced that they were teaming up with McAfee to provide McAfee VirusScan Mobile for its Android mobile users. In July 2012, NTT Docomo acquired Italy's Buongiorno in a deal worth 209 million euros. On October 2007, the prototype Wellness mobile phone of Japan's NTT Docomo Inc. and Mitsubishi Electric Corp. was launched at CEATEC. It checks health with a motion sensor that detects body movement and measures calories, includes a breathalyzer.
On January 24, 2008, NTT Docomo announced a partnership with Google, which allowed all models after the FOMA904i models to view YouTube videos. NTT Docomo is a founding member of the Symbian Foundation. From 2008, Docomo began offering a service called the "Area Mail Disaster Information Service" which broadcasts Earthquake Early Warning messages produced by the Japan Meteorological Agency to its subscribers with compatible handsets; this service is provided free of charge and messages are limited to those areas affected by each particular alert. These alerts have a unique ring tone so they can be distinguished from incoming calls or messages. From 2014, under Civil Protection Law of Japan, Docomo began offering a service called the "Area Mail Disaster and Evacuation Information Service" which broadcasts J-Alert messages produced by the Japan Fire and Disaster Management Agency to its subscribers with compatible handsets; the message is broadcast when the military threat is imminent, volcanic eruptions, or approaching tsunami.
The company's mascot is Docomodake, a mushroom, quite a celebrity in Japan. He is the hero of a Nintendo DS puzzle and platforming video game, Boing! Docomodake DS on 2007 and 2009, he has a wide variety of merchandising such as cell phone straps and plush dolls. As one type of advertising method, there are many types of Docomodakes such as mother and father, which symbolizes the plans that NTT Docomo offers. Emoji, a pictographic language being adopted around the world was first created by NTT DoCoMo; the first emoji was created in 1998 or 1999 by Shigetaka Kurita, part of the team working on NTT DoCoMo's i-mode mobile Internet platform. The first set of 176 12×12 pixel emoji was created as part of i-mode's messaging features to help facilitate electronic communication, to serve as a distinguishing feature from other services. NTT Docomo has a wide range of foreign investments. However, NTT Docomo was not successful in investing in foreign carriers. Docomo had invested large multibillion-dolla
Cellular network
A cellular network or mobile network is a communication network where the last link is wireless. The network is distributed over land areas called cells, each served by at least one fixed-location transceiver, but more three cell sites or base transceiver stations; these base stations provide the cell with the network coverage which can be used for transmission of voice and other types of content. A cell uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed service quality within each cell; when joined together, these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations if some of the transceivers are moving through more than one cell during transmission. Cellular networks offer a number of desirable features: More capacity than a single large transmitter, since the same frequency can be used for multiple links as long as they are in different cells Mobile devices use less power than with a single transmitter or satellite since the cell towers are closer Larger coverage area than a single terrestrial transmitter, since additional cell towers can be added indefinitely and are not limited by the horizonMajor telecommunications providers have deployed voice and data cellular networks over most of the inhabited land area of Earth.
This allows mobile phones and mobile computing devices to be connected to the public switched telephone network and public Internet. Private cellular networks can be used for research or for large organizations and fleets, such as dispatch for local public safety agencies or a taxicab company. In a cellular radio system, a land area to be supplied with radio service is divided into cells, in a pattern which depends on terrain and reception characteristics but which can consist of hexagonal, circular or some other regular shapes, although hexagonal cells are conventional; each of these cells is assigned with multiple frequencies which have corresponding radio base stations. The group of frequencies can be reused in other cells, provided that the same frequencies are not reused in adjacent neighboring cells as that would cause co-channel interference; the increased capacity in a cellular network, compared with a network with a single transmitter, comes from the mobile communication switching system developed by Amos Joel of Bell Labs that permitted multiple callers in the same area to use the same frequency by switching calls made using the same frequency to the nearest available cellular tower having that frequency available and from the fact that the same radio frequency can be reused in a different area for a different transmission.
If there is a single plain transmitter, only one transmission can be used on any given frequency. There is some level of interference from the signal from the other cells which use the same frequency; this means that, in a standard FDMA system, there must be at least a one cell gap between cells which reuse the same frequency. In the simple case of the taxi company, each radio had a manually operated channel selector knob to tune to different frequencies; as the drivers moved around, they would change from channel to channel. The drivers knew which frequency covered what area; when they did not receive a signal from the transmitter, they would try other channels until they found one that worked. The taxi drivers would only speak one at a time; this is, in a sense, time-division multiple access. The first commercial cellular network, the 1G generation, was launched in Japan by Nippon Telegraph and Telephone in 1979 in the metropolitan area of Tokyo. Within five years, the NTT network had been expanded to cover the whole population of Japan and became the first nationwide 1G network.
To distinguish signals from several different transmitters, time-division multiple access, frequency-division multiple access, code-division multiple access, orthogonal frequency-division multiple access were developed. With TDMA, the transmitting and receiving time slots used by different users in each cell are different from each other. With FDMA, the transmitting and receiving frequencies used by different users in each cell are different from each other. In a simple taxi system, the taxi driver manually tuned to a frequency of a chosen cell to obtain a strong signal and to avoid interference from signals from other cells; the principle of CDMA achieves the same result. Other available methods of multiplexing such as polarization-division multiple access cannot be used to separate signals from one cell to the next since the effects of both vary with position and this would make signal separation impossible. TDMA is used in combination with either FDMA or CDMA in a number of systems to give multiple channels within the coverage area of a single cell.
The key characteristic of a cellular network is the ability to re-use frequencies to increase both coverage and capacity. As described above, adjacent cells must use different frequencies, however there is no problem with two cells sufficiently far apart operating on the same frequency, provided the masts and cellular network users' equipment do not transmit with too much power; the elements that determine frequency reuse are the reuse factor. The reuse distance, D is calculated as D = R 3 N {\displaystyle D=R{\sqr
