2015-04-01
981
сellphone (сellular phone) - сотовый телефон
cell site - узел сотовой связи
subscriber - aбонент
as opposed to…- в отличие от…, в противоположность чему-то
to handoff (to handover) - передать, переадресовать
coverage area - зона действия, зона покрытия
wireless - беспроводной (радио)
to page - перелистывать, передавать сообщение
rotary dial - дисковый номеронабиратель
to require - требовать
switchboard - панель управления, коммутатор
to enhance - увеличить, повысить, улучшить
operational reliability - надежность в эксплуатации
rival - конкурент, противник
to introduce - вводить, внедрять
simultaneous - одновременный
spread-spectrum - с широким диапазоном
to assign - назначать, устанавливать
jamming - помехи при приеме, глушение радиопередач
to foil - мешать, расстраивать (планы)
broadband network - широкополосная сеть
Text
A mobile phone or mobile (also called cell phone and hand phone) is an electronic device used for mobile telecommunications (mobile telephony, text messaging or data transmission) over a cellular network of specialized base stations known as cell sites. Mobile phones differ from cordless telephones, which only offer telephony service within a limited range, e.g. within a home or an office, through a fixed line and a base station owned by the subscriber and also from satellite phones and radio telephones. As opposed to a radio telephone, a cell phone offers full duplex communication, automatised calling to and paging from a public land mobile network (PLMN), and handoff (handover) during a phone call when the user moves from one cell (base station coverage area) to another. In addition to the standard voice function, current mobile phones may support many additional services, and accessories, such as SMS for text messaging, email, packet switching for access to the Internet, gaming, Bluetooth, camera with video recorder and MMS for sending and receiving photos and video, MP3 player, radio and GPS.
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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. Cells for mobile phone base stations were invented in 1947 by Bell Labs engineers at AT&T and 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 mobile radio devices have been available since 1973. A patent for the first wireless phone as we know today was issued in US Patent Number 3,449,750 to George Sweigert of Euclid, Ohio on June 10, 1969.
In 1960, the world’s first partly automatic car phone system Mobile System A (MTA) |MTA 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 rotary dial. Calling from the car was fully automatic, while calling to it required an operator. 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 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 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. Martin Cooper, a Motorola researcher and executive is considered to be the inventor of the first practical mobile phone for hand-held use in a non-vehicle setting. Cooper is the first inventor named on "Radio telephone system" filed on October 17, 1973 with the US Patent Office. Using a modern, if somewhat heavy portable handset, Cooper made the first call on a hand-held mobile phone on April 3, 1973 to a rival, Dr. Joel S. Engel of Bell Labs.
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In 1945, the zero generation (0G) of mobile telephones was introduced. Like other technologies of the time, it involved a single, powerful base station covering a wide area, and each telephone would effectively monopolize a channel over that whole area while in use. 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. GSM, short for Global System for Mobile Communications, is one of the leading digital cellular systems. GSM uses narrowband TDMA, which allows eight simultaneous calls on the same
radio frequency. GSM was first introduced in 1991. As of the end of 1997, GSM service was available in more than 100 countries and has become the de facto standard in Europe and Asia. The first SMS text message was sent from a computer to a mobile phone in 1992 in the UK, while the first person-to-person SMS from phone to phone was sent in Finland in 1993.
The first mobile news service, delivered via SMS, was launched in Finland in 2000. In 2001 the first commercial launch of 3G (Third Generation) was again in Japan by NTT DoCoMo on the WCDMA standard. CDMA, short for Code-Division Multiple Access, a digital cellular technology that uses spread-spectrum techniques. Unlike competing systems, such as GSM, that use TDMA, CDMA does not assign a specific frequency to each user. Instead, every channel uses the full available spectrum. Individual conversations are encoded with a pseudo-random digital sequence. CDMA consistently provides better capacity for voice and data communications than other commercial mobile technologies, allowing more subscribers to connect at any given time, and it is the common platform on which 3G technologies are built. CDMA is a military technology first used during World War II by English allies to foil German attempts at jamming transmissions. The allies decided to transmit over several frequencies, instead of one, making it difficult for the Germans to pick up the complete signal. Because Qualcomm created communications chips for CDMA technology, it was privy to the classified information. Once the information became public, Qualcomm claimed patents on the technology and became the first to commercialize it.
The next evolution that recently was released is the 4th generation, also known as Beyond 3G, with the aim to offer broadband wireless access with nominal data rates of 100 Mbit/s to fast moving devices, and 1 Gbit/s to stationary devices defined by the ITU-R 4G systems may be based on the 3GPP LTE (Long Term Evolution) cellular standard, offering peak bit rates of 326.4 Mbit/s. It may perhaps also be based on WiMax or Flash-OFDM wireless metropolitan area network technologies that promise broadband wireless access with speeds that reaches 233 Mbit/s for mobile users. By 2011 it is expected that wireless companies will launch 4G Broadband networks.
Задание I. Ответьте на следующие вопросы:
1. What is a cellphone?
2. What is a cell site?
3. What is the difference between a cellphone and any other types of telephones?
4. What are additional services of a cellphone?
Задание II a) Найдите в тексте информацию о том, каким событием отмечен тот или иной год в истории развития сотовой связи. Особое внимание обратите на следующие годы:
1945, 1947, 1960, 1962, 1969, 1971, 1973, 1991, 1992, 1993, 2000, 2001 и 2011.
б) Расскажите историю развития сотовой связи, предварительно составив план, состоящий из указания года и нескольких ключевых слов.
Например: In 1908- the first patent
was issued
“cave” radio telephone
In 1908 the first patent for a wireless telephone was issued. It was applied to ‘cave’ radio telephone.
