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Cell phones are common tools in modern society, in use with business executives and with high school students alike. Cell phone technology has advanced rapidly since the technology was first put to use in the mainstream market, but the history of mobile phone technology dates as far back as the 1940s.
Early Developments
The first mobile phones were only variations of simple two-way radios, and were not connected to the telephone lines. These devices were mainly used in the military and in police vehicles for communication between different units. Cellular technology existed, but was not yet implemented with the standard telephone lines. The first mobile phones with their own phone numbers were created in the 1950s. The first telephone of this kind, developed in Sweden by Ericsson (one of Sweden’s largest telecommunications companies), was released for the commercial market in Sweden in 1956. This mobile phone bore little resemblance to the cell phones of today; the device weighed 90 lbs. A second, upgraded model was released nine years later that weighed only 20 lbs. Similar cell phones were developed in other countries in Europe and the USSR during this era.
In 1982, the Federal Communications Commission (FCC) approved frequencies in the 824-894 MHz band to be dedicated for cell phone technology use in Advanced Mobile Phone Service (AMPS). The telecommunications company AT&T had been requesting this since 1971. Similar developments were occurring in Europe; in Finland, the Autoradiopuhelin (ARP, or “car radio phone”) mobile phone company was created. ARP is regarded as one of a few “zero generation” cell phone companies, since the phones operated by cells, but transition between cells was not without breaks.
First Generation
The early 1980s saw the development of the first true cell phones that operated from cells, which could switch between cell locations, and which did not require the assistance of a mobile phone operator in order to connect to the telephone network. Analog circuit-switched cell technology became more widespread in Japan, Europe, and the U.S. during this time. In 1983, the Motorola DynaTAC 8000X was the first cell phone in the U.S. to obtain FCC approval. This phone had a battery life of up to 60 minutes for a call and was 10 inches high, not including the flexible rubber antenna. The phone was revolutionary for its time, unique in its portability when compared to the mobile phone units installed in vehicles.
Many of these first generation cell phones were designed for use in cars—the term “car phone” was common—and many users had the phone sets permanently installed in their vehicles. These phones, although much more portable and convenient to use than their predecessors, were still too bulky to fit in a user’s pocket easily and had poor voice quality. The networks were still hindered by low traffic capacity and imperfect handover between cells.
Second Generation
The second generation of cell phone technology came with the upgrade from analog to digital wireless technology in the early 1990s. Frequencies are typically in the 900 MHz or 1800 MHz range, and the defining characteristics of second generation mobile phone technology are digital circuit switched transmission and faster phone to network signal process. In terms of physical appearance, the large “brick” design of first generation phones gave way to the smaller designs more familiar to today’s users. Second generation phones can truly fit in the palm of a hand, and usually weigh only about 100-200 grams. Additionally, second generation cell phone technology supports Short Message Service (SMS), or “text messaging,” with phones supporting E.161, the standard keypad alphabet layout. Later developments in second generation phones (sometimes called “2.5 generation”) saw the introduction of such features as web browsing, voice mail, the ability to use navigational maps, fax, and large emails.
Third Generation
In the early 2000s, the first of the third generation phones began to appear in the commercial market. Companies had started designing third generation mobile phone technology not long after the second generation phones hit the market, but the first phones did not reach the market until 2001, in Japan. Third generation phones were not designed primarily around a specific telecommunication technology, but around a set of requirements that included higher data rates for indoor and outdoor use. Europe and the U.S. followed shortly after in 2002 and 2003 with third generation mobile phone designs.
To enable more users, code division multiple access (CDMA) technology was implemented, so multiple transmissions could be permitted on the same frequency. This represented an improvement in convenience and ability over TDMA, or time division multiple access, because of the elimination of frequency interference and the limits of potential bandwidth of TDMA channels. The latest versions, such as CDMA2000 3x or UMTS (Universal Mobile Telecommunications System), offer higher Mbit/s rates, and operate at more varied MHz frequencies.
The third generation phone designs were often smaller and more convenient than their second generation predecessors. Also, high speed data transmission and access made web browsing, text messaging, email use, and other features easier. Many phones began to have built-in cameras and the ability to send pictures to other cell phone users or to email addresses. Third generation phone technology also offers more call security. As versatile and convenient as these third generation cell phones may be, they have come with a few disadvantages. One of the biggest issues facing third generation cell phone technology companies is cost. Third generation technology is expensive, both in phone model design and in the required infrastructure to support third generation technology. Third generation licensing is sometimes expensive, and customers can face a wide variety of license agreements depending on the service provider. Because of the difficulties in implementing third generation infrastructure, sometimes these phones have limited service areas. However, most of these problems are being resolved, and the third generation phone technology is still being improved.
The Future
Fourth generation phones are not yet implemented commercially, but the technology is being developed. Estimates currently place fourth generation mobile phone technology to become operational and commercially available somewhere around 2012-2015. When this happens, phone companies are expecting that most if not all the coverage and data rate issues will be resolved, to allow cell phone users complete and fast use wherever they are. Smooth handoff, very fast data rates, high network capacities, and global roaming abilities are some of the goals in mind for fourth generation mobile phone technology.
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