Cell phone (mobile) or mobile phones or mobile or is also called an electronic telecommunications device that has the same basic capabilities with conventional fixed-line telephone, but can be taken anywhere (portable, mobile) and do not need connected to the telephone network using a wired (wireless). Currently there are two mobile phone network is the GSM system (Global System for Mobile Telecommunications) and the CDMA system (Code Division Multiple Access).
History
The inventor of the first mobile phone system is Martin Cooper, a Motorola employee on the date of April 3, 1973, although widely touted inventor cell phone is one of a team of Motorola division (division where Cooper worked) with the first model is the DynaTAC. The idea hatched by Cooper is a communication tool that is small and easy to carry travel flexibly.
Cooper and his team face the challenge of how to put all the electronic material into such a small device for the first time. But eventually a first cell phone was successfully completed with a total weight of weighing two kilograms. To produce it, Motorola will cost the equivalent of U.S. $ 1 million. "In 1983, portable cell phone worth U.S. $ 4 thousand (Rp36 million) equivalent to U.S. $ 10 thousand (Rp90 million).
After successfully producing mobile phones, the next biggest challenge is adapting infrastructure to support the communication system of the mobile phone by creating a network system that only requires 3 MHz spectrum, the equivalent of five TV channels are channeled to the rest of the world.
Other figures are known to be very instrumental in the mobile communications world is Amos Joel Jr. who was born in Philadelphia, March 12, 1918, he was recognized worldwide as an expert in the field of switching. He received a bachelor's degree (1940) and master's (1942) in electrical engineering from MIT. Not long after studies, he began his career over 43 years (from July 1940-March 1983) at the Bell Telephone Laboratories, where he received more than 70 U.S. patents in the field of telecommunications, particularly in the field of switching. Amos E Joel Jr., making the system connector (switching) cell phone from one region to another region of the cell. This switching should work when mobile users move or move from one cell to another so that the conversation is not interrupted. Since the discovery of this Joel Amos cell phone use be comfortable.
Functions and features
Besides functioning to make and receive phone calls, the phone also has the function generally sending and receiving short messages (short message service, SMS). There is also a provider of mobile phone services in some countries that provide third generation (3G) by adding videophone services, as a means of payment, as well as for online television on their mobile phones. Now, mobile phones are becoming multifunctional gadgets.
Following the development of digital technology, now the phone is also equipped with a wide selection of features, such as can capture radio and television broadcasts, the software audio players (MP3) and video, digital camera, game, and internet services (WAP, GPRS, 3G). In addition to these features, the phone is now embedded computer features. So on the phone, people can change the function of the mobile phone into a mini-computer. In the business world, this feature is very helpful for business people to do all the work in one place and make the job completed in a short time.
Type a phone based on function
Mobile business
This type of mobile phone aimed at people who want a business device in your hand, usually have a phone that has this capability classified as smart phones (smartphones). A variety of business applications contained in this phone and can make your office work can be seen and done in a mobile phone.
Mobile entertainment
This type of phone is a multimedia phone manifold, where all activities related to music, art, photos, and other social can be fixed by a mobile phone. Many of these type of phone has its own variants, such as music phones, camera phones, and mobile social networking.
Fashion phone
These types of phones rely more zoom, and can make its owner very satisfied though with features that seem simple. But behind it all, a fashion phone can cost many times the price of the most advanced mobile phones. Nowadays mobile phones are to be found more expensive than the price of a vehicle, even more expensive than the price of a house.
Standard Mobile
This type of phone is intended for those who want a phone that is simple, features embedded in this phone is a core feature, no new technology is pinned.
Development
Generation 0 (zero)
History of mobile phones can not be separated from the development of radio. Early discovery of cellular phones began in 1921 when the Detroit Michigan Police Department tried to use the phone one-way car. Then, in 1928 the Detroit Police Department began using regular one-way radio communication on all patrol cars with a frequency of 2 MHz. on subsequent development, 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 a generation 0 cell phone or 0-G, where mobile phones were introduced.After removing the SCR536, then in 1943 returned Galvin Manufactory Corporation issued a portable FM two-way radios first named SCR300 backpack model for the U.S. Army's equipment weighs about 35 pounds and be able to work effectively within the operating range of 10 to 20 miles.
System 0-G mobile phones still use a VHF radio system to connect the phone directly to the PSTN landline. The weakness of this system is the problem of congestion on the network which then led to efforts to change the system.Generation 0 ended with the invention of the modern concept by engineers from Bell Labs in 1947. They find the concept of using hexagonal phone as a basic cell phone. However, this new concept was developed in the 1960s.
Generation I
The first generation of mobile phones also called 1G. 1-G is the first true mobile phone. In 1973, Martin Cooper of Motorola Corp. discovered and introduced the first mobile phone to the public on April 3, 1973. Cellular phone was found 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 frequency between 825 Mhz-894 Mhz and 800 Mhz band operated on. Because it is analog, then the system is still used regionally. One drawback generation 1-G is 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 placing a call, the user mobility is limited to the coverage area of a mobile phone.
Generation II
The second generation or 2-G appeared in about 1990. 2G in the U.S. are already using CDMA technology, while in Europe uses GSM technology. Using the standard GSM frequencies of 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 mobile phones with voice mail, call waiting, and SMS. Mobile 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 power. The advantages of the 2G generation is the size and weight of the smaller and lower radio signals, thus reducing the harmful effects of radiation users.
Generation III
This generation is also called 3G that allows network operators to give their users a wider range, including internet video calls as well as high-tech. Within there are 3 standard for 3G telecom world ie Enhance datarates for GSM Evolution (EDGE), Wideband-CDMA and CDMA 2000. Weakness of the 3G generation is relatively higher costs, and the lack of network coverage because this technology is still new. But the interesting thing in this generation is to start the inclusion of the operating system on mobile phones that makes feature more complete PC functionality even closer. The operating system used, among others, Symbian, Android and Windows Mobile
Generation IV
This generation is also called Fourth Generation (4G). 4G is a phone system that offers a new approach and infrastructure solutions that integrate existing wireless technologies including wireless broadband (WiBro), 802.16e, CDMA, wireless LAN, Bluetooth, and others. Heterogeneity of 4G systems based 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 delivers fast data delivery services to accommodate a variety of applications such as multimedia, video conferencing, online gaming, and others.
How it works
Inside the phone, there is a speaker, microphone, keyboard, display screen, and powerful circuit board with microprocessors that make every phone as a mini computer. When dealing with a wireless network, a set of technologies that allow users to make calls or exchange data with other phones or computers.
Wireless networks operate in a network that divides cities or regions into cells smaller. The cell covers several city blocks or up to 250 square miles. Every cell uses a set of radio frequencies or channels to provide services in a specific area. The radio power must be controlled to limit the geographic reach of the signal. Hence, the same frequencies can be reused in nearby cells. So many people can have conversations simultaneously in different cells in the entire city or region, even though they are in one channel.
In each cell, there is a base station that contains a wireless antenna and other radio equipment. Wireless antenna in each cell will menghbungkan callers to the local telephone network, Internet, or other wireless networks. Mentransimiskan wireless antenna signal. When the phone is turned on, the phone searches for a signal to confirm that the service has been available. Then the phone will transmit a specific identification number, so that the network can verify consumer information-such as a wireless service provider, and phone number.
Calls from mobile phones to home phones
When calling from a regular home phone to a cell phone, the call is a walk through a nearby wireless antennas and wireless will be changed by the conductors' to traditional landline telephone system. The call will then be directed to the traditional telephone network and to the person who is the destination of the call.
Calls from Mobile to Mobile
When making a call from this, the call will be routed through the network to the introduction of wireless landline will be routed to the recipient or wireless network 'to the cells closest to the person who is the destination of the call. While talking on the phone, the mobile phone will capture the voice and converts the sound into radio frequency energy (radio waves).
The radio waves will travel through the air to find the nearest base station receiver. The base station will then send the call through a wireless network to arrive at the person who is the destination phone.
Long distance calls
When making a call to someone who is outside the country of the caller was, the call is classified as an international call. Calls are routed in the center of long-distance exchange, which connects the call between states or around the world through fiber optic cable.
Prices Mobile Phones
With more and more people are using cell phones or mobile phones, then mass production can be done. Mobile price charts around the world tend to be more affordable over the years. If the first cell phone or mobile phone is a rare item, and exclusive only to those who are able, the upper class, it is currently almost all walks of life can enjoy the convenience of using mobile phones to communicate.
To suppress the price of mobile phones getting cheaper to be obtained, then some phone vendors work closely with telecom operators for bundling the phone with the service provider with the contract system. In this way so the cheaper the price of the phone, as it can be repaid as well as subscription fees communications package offered by the operator.
Mobile phones have also evolved. Now mobile phones are not only used to carry voice conversation or text (SMS), but can also run a variety of advanced computing applications. Hence there is a segment called the cell phone with a smartphone (smart phone / smart phone). Just as mobile phones more affordable price, the price of smart phones in the early days of exorbitant price, now also be enjoyed by the middle to lower. One of the world revolution in the smartphone market is the presence since iOS and Android.
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