The Development of Phone Cellular

Early generations
History of the discovery of a cell phone can not be separated from the development of radio. Early discovery of cell phones began in 1921 when the Detroit Police Department, Michigan tried to use a car phone in one direction. Then, in 1928 the Detroit Police Department began using a one-way radio communication on all patrol cars with a frequency of 2MHz.
In further developments, radio evolved into a two-way communication with'''' frequency modulated (FM).
In 1940, Galvin Manufactory Corporation (now Motorola) to develop portable handie-talkie SCR536, which means a communication tool on the battlefield during World War II. This period is the next generation mobile phone 0 or 0-G, where mobile phones were introduced.
After removing the SCR536, then in 1943 Galvin Manufactory Corporation partable reissue the first two-way FM radio named SCR300 backpack model for the U.S. Army's equipment weighs about 35 pounds and can work effectively within the operating range of 10 to 20 miles.

Mobile phone system 0-G still use a VHF radio system to connect the phone directly to the PSTNlandline. The weakness of this system is the problem of congestion on the network which then led to attempts to change the system.
Generation 0 ended with the discovery of the modern concept by engineers from Bell Labs in 1947. They found the concept of using hexagonal phone as a basic cell phone. However, this new concept was developed in the 1960s.

Generation 1
The first generation mobile phone called 1G. 1-G is the first true mobile phone. In 1973, Martin Cooper of Motorola Corp. found a cell phone first and introduced to the public on 3 April 1973. Cell phones were invented by Cooper weighs 30 ounces or about 800 grams. This invention has changed the world forever. The technology used is 1-G is still analog and known as AMPS. AMPS uses frequencies between 825 MHz and 894 MHz operation on Band800 Mhz. Because it is analog, then the system is still used regionally. One drawback is the generation of 1-G because the size is too big to be held by the hand. This is because the large size of the purposes of power and poor battery performance. Additionally generation 1-G still has problems with mobility users. When making a call, the user mobility is limited to coverage area of ​​a mobile phone.

Generation 2
The second generation or 2-G appeared around 1990's. 2G in the United States are already using CDMA technology, whereas in Europe uses GSM technology. Using the standard GSM frequencies 900 MHz and 1800 MHz frequencies. With these frequencies, GSM has a capacity greater customer. On the 2G generation analog signal has been replaced with a digital signal. The use of digital signal equip phones with voice mail, call waiting, and SMS.
Cell phones in this generation also has a smaller size and lighter due to the use of digital chip technology. The smaller size is also due to the need for a smaller battery. Advantages of generation 2G is the size and weight of the smaller and lower radio signals, thus reducing the harmful effects of radiation users.

Generation 3
This generation is also called 3G that allows network operators to give their users a wider range, including the Internet as well as high-tech video call. Within there are 3 standard for 3G telecom world ie Enhance Datarates for GSM Evolution (EDGE), Wideband-CDMA and CDMA 2000. The downside of the 3G generation is relatively higher costs, and the lack of network coverage because it is still new technology. But what's interesting in this generation is the inclusion of the operating system from the phone that makes phone features the full PC functionality even close. Operating systems used include Symbian, Android and Windows Mobile

Generation 4
This generation is also called Fourth Generation (4G). 4G is a phone system that offers a new approach and infrastructure solutions that integrate wireless technologies that already exist, including wireless broadband (WiBro), 802.16e, CDMA, wireless LAN, Bluetooth, and others. 4G systems based on heterogeneous IP network that allows users to use multiple systems anytime and anywhere. 4G also gives its users high speed, high volume, good quality, global reach, and flexibility to explore a variety of different technologies. Finally, 4G provides fast data delivery services to accommodate a variety of applications such as multimedia, video conferencing, online gaming, and others.

The Development of Phone Cellular Rating: 4.5 Diposkan Oleh: Alif Shahab

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