CELL PHONE

CELL PHONE OR 

 The mobile phone is an electronic device that allows wireless access to the cellular network or mobile. Cell is called in most Latin American countries because the service operates through a network of cells, where each antenna signal repeater is a cell, although there are satellite mobile telephone networks. Its main feature is its portability, which allows you to communicate from almost anywhere. The main function is voice communication such as telephone. From the century, mobile phones have acquired features that go far beyond simply just call or send text messages, it could be said to be unified (not replaced) with various devices such as PDA, camera , electronic calendar, alarm clock, calculator, micro-projector, GPS or multimedia player and can perform many actions on a small portable device that takes virtually everyone in developed countries. This type of evolution of the mobile phone is known comosmartphone. The first record is about the mobile phone company Motorola, with its modeloDynaTAC 8000X. The model was designed by engineer Rudy Krolopp Motorola in 1983. The model weighed just under a kilo and was worth nearly U.S. $ 4000. Krolopp then the team will incorporate research and development led by Martin Cooper Motorola. Both Cooper and Krolopp appear as owners of the original patent. From the DynaTAC 8000X, Motorola would develop new models like the Motorola MicroTAC, launched in 1989 and the Motorola StarTAC, released in 1996 to market. Currently have major mobile touch phones that follow the wake of the iPhone. 

http://es.wikipedia.org/wiki/Celular

HISTORY OF THE CELL PHONE 

The cell phone goes back to the beginning of World War II, which already saw that it was necessary distance communication, that is why the company created a team called Motorola Talkie Handie H12-16, which is a device that allows contact with the troops via radio waves at that time did not exceed more than 600 kHz. It was only a matter of time before the two technologies of Tesla and Marconi to join and give light communication via radio-telephones: Martin Cooper, a pioneer and as the father of mobile telephony, made the first radio telephone between 1970 and1973, United States, and in 1979 appeared the first systems on sale in Tokyo (Japan), manufactured by the company NTT.European countries are not left behind and in 1981 introduced a system similar to Scandinavia AMPS (Advanced Mobile Phone System). In 1985 he began to refine and shape the characteristics of this revolutionary new system because it allowed to communicate at a distance. So in the 1980s it was creating a team that occupied similar resources to Handie Talkie but was intended for people who were usually big business and should be reported, this is where setting up the phone and dials a milestone in the history of wireless components and that this team could talk to anytime and anywhere. 

FIRST CELL PHONE 

This is the first cell phone in history, the grandfather of what we know today. His name is Motorola DynaTAC 8000X, and first appeared in 1983. It was heavy, 28 ounces (about 780 grams) and measured 33 "x 9" x 4.5cm.. "Obviously it was analog and had a small LED display. The battery was only for an hour of conversation or 8 hours of stand -by. The sound quality was very bad, was heavy and unattractive, but still, there were people who paid U.S. $ 3.995 U.S. dollars that cost, which made it a luxury item and only available to certain social spheres, even Despite its design and weight. The first to use them were businessmen, executives and high net worth, primarily because of a company depends desarrollosocioeconómico be communicated effectively connected with suppliers, customers, employees, governments and regulators. Another cause of this usage is bounded due to the high costs of these services involve the lack of competition among cell phone companies that force down prices and has improved the technical problems. By 1984, the company managed to sell 900,000 phones, an amount that was intended to reach only in 2000.

http://www.avancestecnologicos.org/celulares

EVOLUTION AND TECHNOLOGY CONVERGENCE 

The evolution of mobile phones has reduced its size and weight, since that first phone in 1983 that weighed 780 grams, the current more compact and higher performance of service. The development of smaller batteries and longer lasting, sharper screens and colors, incorporating more user-friendly software, make the phone a very appreciated in modern life. The advance of technology has made these devices incorporate features that not long ago seemed futuristic, like games, play MP3 and other formats Demus, email, SMS, PDA PDA, digital photography and digital video, video call and navigation porInternet to digital TV. Mobile phone companies are already thinking about new applications for this little device that accompanies us everywhere. Some of these ideas are: medium of exchange, people locator and identifier. Always take into account the great advances suffered from the first mobile phone to the present. The stage of evolution of cell phones can be divided into three generations: 

FIRST-GENERATION CELL PHONES 

The first generation goes from the appearance of the first cell phone in the world market known as "brick" (DynaTAC 8000X) until the late 80's. These were characterized as being of limited use analog technology for voice communications. The dominant technology in this generation was the AMPS (Advanced Mobile Phone System) 

SECOND GENERATION OF CELL PHONES 

The second generation makes its appearance in the 90's, most are digital and some benefits are highly valued as extended battery life, the possibility of safer and higher definition sound.These phones, and some analog phones, have the possibility of sending and receiving text messages (SMS), however, is not yet in these years the "boom" of this tool in recent years has become commoditized so incredible. A late fever occurs by cell phones, ordinary people are added to the list of users, favored by the exchange rate and competition between different companies. The predominant technologies are: GSM (Global System for Mobile Communications), IS-136 (also known as TIA/EIA136 or ANSI-136) and CDMA (Code Division Multiple Access) and PDC (Personal Digital Communications), the latter used in Japan . 

THIRD GENERATION CELL PHONES 

It is characterized by the above technologies together with new technologies incorporated into mobile phones. Inauguration of the mass of cell phones. In recent years cell phones are equipped with a chip, SIM card, which is entered all lainformación. One of the most important causes of the spread in consumption can reach up to humble society is the existence in the market for GSM handsets so-called "low range", such as Nokia 1100, Sagem XT, Motorola C200 or C 115, Alcatel, Siemens and Sony Ericsson T106 A56, all at very affordable prices and surrounded promotions. However, the need to belong, to achieve a certain social status no longer present, the cellular communication addition to its use is not without symbolic value of class membership in both young and senior executives who even today still to benefit from their services. Next to these devices "under" an infinite variety of digital photo camera, some even allow minutes of film, have a color display, very fast internet connection (EDGE), multimedia messaging (MMS) and access to box e-mail (POP3). In 2001 launches in Japan's 3G phones, which are based on UMTS (General Mobile Telecommunications Service). This case was one of the final steps in what is mobile and information technology. The most significant was the addition of a second camera for video calls, ie talk to someone and see it while using the mobile phone. This evolution in mobile phones today means that we are talking about a much broader market and therefore varied. All reflected in advertising campaigns increasingly specific on one side and the other in the amount of promotions and plans that try to cover the entire spectrum of potential customers.

http://www.samsung.com/co/consumer/mobile-phones/mobile-phones/index.idx?pagetype=type_p2&

Mobile access technology. 

Currently there are three technologies commonly used to transmit information networks: • Multiple Access Frequency Division (FDMA, for its acronym in English) • Multiple Access Time Division (TDMA, for its acronym in English) • Division Multiple Access (CDMA, for its acronym in English) Although these technologies sound complicated, you can get an idea of ​​how examining every word of names. The primary difference lies in the access method, which varies between: Often used in the FDMA Time used in TDMA Unique codes, which are provided to each call on the CDMA technology. The first part of the names of the three technologies (Multiple Access) means that more than one user (multiple) you can use (access) each cell. Next we will detail, without going into complicated technical details, how each of the three common technologies. The FDMA separates the spectrum into distinct voice channels by splitting the bandwidth into pieces (frequencies) uniforms.FDMA technology is mostly used for analog transmission. This technology is not recommended for digital transmissions, even when it is capable of carrying digital information. TDMA technology compresses conversations (digital), and sends each signal using the radio for a third time only. The compression of the voice signal is possible because digital information can be reduced in size by binary information (ones and zeros). Due to this compression, TDMA has three times the capacity of an analog system that uses the same number of channels. CDMA technology is very different from TDMA technology.CDMA, after digitizing the information, transmitted across the bandwidth available. Multiple calls are overlaid on the channel, and each has a unique sequence code. Using the CDMA technology, it is possible to compress 8 to 10 digital calls to occupy these occupy the same space as a call on the analog system. In theory, TDMA and CDMA technologies must be transparent to each other (they should not interfere or degrade the quality), but in practice there are some minor problems such as differences in the volume and quality between the two technologies