Cell Phones Changes Our Lives
Essay by people • July 22, 2011 • Essay • 399 Words (2 Pages) • 2,310 Views
Cell phones changes our lives
These years cell phone is becoming necessities of people lives. It is not only changes our way of communication, but also influences kinds of fields of our lives. Some people have said they cannot live without cell phone. The role of cell phone has surpassed computer and car. Although the history of cell phone is shorter than computer and car, the speed of its development is surprising.
The beginning history of cell phones stem from the early days of 1940s based on radio technology. In this period, cell phones were used by police. It functions is connecting with a central base or communicating with other police officers. It is very similar to the two-ways radio phone used by drivers of taxis and buses.
The first electronic signal cell phone born in the 1960s. At that times, the technology of mobile phone already available. However, the users were restricted by a certain cell areas. These areas were serviced by base stations covering a limited area. If users are out of these areas, they will be out of serviced. Therefore, the needs for cell phone without limitation of distance made the development history of mobiles go further and further again. The above limitation of distance was resolved by an engineer at Bell Labs. Amos Edward Joel discovered and developed what he termed as the handoff system. After that, users can use the cell phone without distance restricted anymore.
First Generation Cell Phones: As early as 1973, Mary Cooper, a Motorola staff invented the first portable cell phone called Motorola DynaTAC 8000X. the technology of communications are used until today. At that time, cell phone is as big as a brick. It is not portable. With the technology development, the cell phone change smaller and smaller.
Second Generation Cell Phones: In the 1900s, the technology of cell phone worked on mobile phone system such as GSM, IS-136(TDMA) and IS-95(CDMA). It is considered being second generation (2G). 2G cell phones were much smaller than 1G, around 100 to 200 grams. They are becoming popular between people with weight and price becoming acceptable by customers.
Third Generation Cell Phones: The 3G cellular phone is the technology that is currently available nowadays. 3G was soon launched after 2G due to a lot of technology and service innovations in these years. The standards that are used in 3G cell phones are different depending on the network.
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