A mobile phone or mobile (also called cellphone and handphone[1]) is an electronic device Electronics is that branch of science and technology which makes use of the controlled motion of electrons through different media and vacuum. The ability to control electron flow is usually applied to information handling or device control. Electronics is distinct from electrical science and technology, which deals with the generation, used for mobile telecommunications Mobile telephony is the provision of telephone services to phones which may move around freely rather than stay fixed in one location. Mobile phones connect to a terrestrial cellular network of base stations , whereas satellite phones connect to orbiting satellites. Both networks are interconnected to the public switched telephone network (PSTN) (mobile telephone A mobile phone or mobile is an electronic device used for mobile telecommunications (mobile telephone, 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 telephone service within limited range, e.g. within a home or an office,, text messaging Text messaging refers to the exchange of brief written messages between mobile and portable devices over cellular networks. While the original term was derived from referring to messages sent using the Short Message Service (SMS), it has since been extended to include messages containing image, video, and sound content (known as MMS messages). The or data transmission) over a cellular network A cellular network is a radio network made up of a number of cells, each served by at least one fixed-location transceiver known as a cell site or base station. 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 of specialized base stations The term base station can be used in the context of land surveying and wireless communications known as cell sites A cell site is a term used to describe a site where antennas and electronic communications equipment are placed on a radio mast or tower to create a cell in a cellular network. A cell site is composed of a tower or other elevated structure for mounting antennas, and one or more sets of transmitter/receivers transceivers, digital signal processors,. Mobile phones differ from cordless telephones A cordless telephone or portable telephone is a telephone with a wireless handset that communicates via radio waves with a base station connected to a fixed telephone line, usually within a limited range of its base station . The base station is on the subscriber premises, and attaches to the telephone network the same way a corded telephone does, which only offer telephone service within 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 A satellite telephone, satellite phone, or satphone is a type of mobile phone that connects to orbiting satellites instead of terrestrial cell sites. Depending on the architecture of a particular system, coverage may include the entire Earth, or only specific regions and radio telephones A radiotelephone is a communications device that allows two or more people to talk using radio. However, there is controversy about the definition of the term. There are also conflicts between British English usage, American English usage, and historic use. As opposed to a radio telephone A radiotelephone is a communications device that allows two or more people to talk using radio. However, there is controversy about the definition of the term. There are also conflicts between British English usage, American English usage, and historic use, a cell phone offers full duplex A duplex communication system is a system composed of two connected parties or devices that can communicate with one another in both directions communication, automates calling to and paging In computer operating systems, paging is one of the memory-management schemes by which a computer can store and retrieve data from secondary storage for use in main memory. In the paging memory-management scheme, the operating system retrieves data from secondary storage in same-size blocks called pages. The main advantage of paging is that it from a public land mobile network In telecommunication, a public land mobile network is a network that is established and operated by an administration or by a recognized operating agency (ROA) for the specific purpose of providing land mobile telecommunications services to the public (PLMN A public land mobile network is a United States federal regulatory term in telecommunications. A PLMN is a network that is established and operated by an administration or by a recognized operating agency (ROA) for the specific purpose of providing land mobile telecommunications services to the public), and handoff In cellular telecommunications, the term handover or handoff refers to the process of transferring an ongoing call or data session from one channel connected to the core network to another. In satellite communications it is the process of transferring satellite control responsibility from one earth station to another without loss or interruption (handover) during a phone call when the user moves from one cell (base station coverage area) to another. Most current cell phones connect to a cellular network A cellular network is a radio network made up of a number of cells, each served by at least one fixed-location transceiver known as a cell site or base station. 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 consisting of switching points and base stations The term base station can be used in the context of land surveying and wireless communications (cell sites) owned by a mobile network operator A mobile network operator , also known as mobile phone operator (or simply mobile operator or mobo ), carrier service provider (CSP), wireless service provider, wireless carrier, or cellular company, is a telephone company that provides services for mobile phone subscribers. In addition to the standard voice function, current mobile phones may support many additional services GSM services are a standard collection of applications and features available to mobile phone subscribers all over the world. The GSM standards are defined by the 3GPP collaboration and implemented in hardware and software by equipment manufacturers and mobile phone operators. The common standard makes it possible to use the same phones with, and accessories The typical cell phone has become somewhat obsolete; current cell phones offer embedded features such as memory databases for storing frequently called numbers, locking features for theft deterrence, crystallized displays, internet connection capabilities, and other useful features. With the addition of popular culture, science, and marketing the, such as SMS Short Message Service is a communication service component of the GSM mobile communication system, using standardized communications protocols that allow the exchange of short text messages between mobile phone devices. SMS text messaging is the most widely used data application in the world, with 2.4 billion active users, or 74% of all mobile for text messaging Text messaging refers to the exchange of brief written messages between mobile and portable devices over cellular networks. While the original term was derived from referring to messages sent using the Short Message Service (SMS), it has since been extended to include messages containing image, video, and sound content (known as MMS messages). The, email Electronic mail, commonly called email or e-mail, is a method of exchanging digital messages across the Internet or other computer networks. Originally, email was transmitted directly from one user to another computer. This required both computers to be online at the same time, a la instant messenger. Today's email systems are based on a store-and-, packet switching Packet switching is a digital networking communications method that groups all transmitted data – irrespective of content, type, or structure – into suitably-sized blocks, called packets. Packet switching features delivery of variable-bit-rate data streams over a shared network. When traversing network adapters, switches, routers and other for access to the Internet The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks of local to global scope that are linked by a broad array of electronic and, gaming, Bluetooth Bluetooth is an open wireless technology standard for exchanging data over short distances from fixed and mobile devices, creating personal area networks (PANs) with high levels of security. Created by telecoms vendor Ericsson in 1994, it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices,, infrared Infrared light is electromagnetic radiation with a wavelength between 0.7 and 300 micrometres, which equates to a frequency range between approximately 1 and 430 THz, camera A camera is a device that records/stores images. These images may be still photographs or moving images such as videos or movies. The term camera comes from the camera obscura , an early mechanism for projecting images. The modern camera evolved from the camera obscura with video recorder and MMS Multimedia Messaging Service, or MMS, is a standard way to send messages that include multimedia content to and from mobile phones. It extends the core SMS capability which only allowed exchange of text messages up to 160 characters in length for sending and receiving photos A photograph is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic imager such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and and video Video is the technology of electronically capturing, recording, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes in motion, MP3 player A digital audio player, shortened to DAP, usually referred to as an MP3 player, is a consumer electronic device that has the primary function of storing, organizing and playing audio files, in contrast to physical medium audio players, which play music from a physical medium on which the audio files are mechanically or electronically printed, radio Radio is the transmission of signals by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space. Information is carried by systematically changing some property of the radiated waves, such as and GPS The Global Positioning System is a space-based global navigation satellite system that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites. It is maintained by the United States government and is freely.
The International Telecommunication Union The International Telecommunication Union is the eldest organization in the UN family still in existence. It was founded as the International Telegraph Union in Paris on 17 May 1865 and is today the leading United Nations agency for information and communication technology issues, and the global focal point for governments and the private sector estimated that mobile cellular subscriptions worldwide would reach approximately 4.6 billion by the end of 2009. Mobile phones have gained increased importance in the sector of Information and communication technologies for development Information and Communication Technologies for Development is a general term referring to the application of Information and Communication Technologies (ICTs) within the field of socioeconomic development or international development. ICT4D concerns itself with directly applying information technology approaches to poverty reduction. ICTs can be in the 2000s and have effectively started to reach the bottom of the economic pyramid In economics, the bottom of the pyramid is the largest, but poorest socio-economic group. In global terms, this is the 2.5 billion people who live on less than $2.50 per day. The phrase “bottom of the pyramid” is used in particular by people developing new models of doing business that deliberately target that demographic, often using new.[2]
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History
Mobile car phone, 1964 Portable cellphone, 1970s Man using cell phone, 1973 Main article: 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 to emergence of the modern mobile phone and its associated services Analog Motorola DynaTAC The Motorola DynaTAC 8000X was the first mobile phone to receive FCC acceptance in 1983. DynaTAC was actually an abbreviation of Dynamic Adaptive Total Area Coverage 8000X Advanced Mobile Phone System Advanced Mobile Phone System was an analog mobile phone system standard developed by Bell Labs, and officially introduced in the Americas in 1983 and Australia in 1987. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s. As of February 18, 2008, carriers in the United States were mobile phone as of 1983In 1908, U.S. Patent 887,357 for a wireless telephone was issued to Nathan B. Stubblefield Nathan B. Stubblefield was an American inventor and Kentucky melon farmer. It has been claimed that Stubblefield invented the radio before either Nikola Tesla or Guglielmo Marconi, but his devices seem to have worked by audio frequency induction or, later, audio frequency earth conduction (creating disturbances in the near-field region) rather of Murray, Kentucky Murray is a city in Calloway County, Kentucky, United States. The population was 14,950 at the 2000 census and has a micropolitan area population of 36,348 according to 2008 Census Bureau estimates. Murray's population increased to 16,557 according to the 2009 Census Bureau estimates. It is the county seat of Calloway County and is the home of. He applied this patent to "cave radio" telephones and not directly to cellular telephony Mobile telephony is the provision of telephone services to phones which may move around freely rather than stay fixed in one location. Mobile phones connect to a terrestrial cellular network of base stations , whereas satellite phones connect to orbiting satellites. Both networks are interconnected to the public switched telephone network (PSTN) as the term is currently understood.[3] Cells for mobile phone base stations were invented in 1947 by Bell Labs Bell Laboratories is the research and development organization of Alcatel-Lucent and previously of the American Telephone & Telegraph Company (AT&T) engineers at AT&T AT&T Inc. is the largest provider of fixed telephony in the United States, and also provides broadband and subscription television services. AT&T is the second largest provider of mobile telephony service in the United States, with over 90.1 million wireless customers, and more than 210 million total customers and further developed by Bell Labs during the 1960s. Radiophones A radiotelephone is a communications device that allows two or more people to talk using radio. However, there is controversy about the definition of the term. There are also conflicts between British English usage, American English usage, and historic use have a long and varied history going back to Reginald Fessenden Reginald Aubrey Fessenden was a Canadian inventor who performed pioneering experiments in radio, including early—possibly the first— transmissions of voice and music. In his later career he received hundreds of patents for devices in fields such as high-powered transmitting, sonar, and television's invention and shore-to-ship demonstration of radio telephony, through the Second World War Albania · Australia · Austria · Azerbaijan · Belarus · Belgium · Brazil · Bulgaria · Burma · Cambodia · Canada · Ceylon (Sri Lanka) · Channel Islands · China · Czechoslovakia · Denmark · Dutch East Indies · Egypt · Estonia · Finland · France · Germany · Gibraltar · Greece · Greenland · Hong Kong · Hungary · Iceland · 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 George H. Sweigert is widely credited as the first inventor to hold a patent for the invention of the cordless telephone. Google Patents link here. [] 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 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.[4][5]
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; see for example Fluhr and Nussbaum,[6] Hachenburg et al.[7] , 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.
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, after a long race against Bell Labs for the first 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;[8] 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.[9][10] Using a modern, if somewhat heavy portable handset, Cooper made the first call on a hand-held mobile phone on April 3, 1973 to his rival, Dr. Joel S. Engel of Bell Labs.[11]
Analog cellular telephony (1G)
Main article: 1GThe 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 Telephone (NMT) system in Denmark, Finland, Norway and Sweden in 1981.[12]. NMT was the first mobile phone network featuring international roaming. The Swedish electrical engineer Östen Mäkitalo 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.[13][14]
Personal Handy-phone System mobiles and modems used in Japan around 1997–2003Several 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 Ericsson AXE 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.
A 1991 GSM mobile phone
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Sep 02, 2009 (Japan Times - McClatchy-Tribune Information Services via COMTEX) -- Cell phones in Japan have evolved as a virtual extra appendage that people ...
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dandelionsalad
Wed, 30 Jun 2010 20:54:40 GM
Today Congressman Dennis J. Kucinich (D-OH) announced his intent to introduce a bill to create a new national research program to study . cell phones. and health, require an update of the decades-old Specific Absorption Rate (SAR), ...
Q. I've seen casings for k850i and they include magnetic locks in the the flap. I don't know if they can be harmful to cellular phones or not. Even the original casings from SE include magnets. So, are they harmful?
Asked by Ralph - Wed Oct 8 15:25:13 2008 - - 1 Answers - 1 Comments
A. No. The magnets are not powerful enough to do any harm.
Answered by G'DogMoney - Wed Oct 8 17:47:31 2008
