Generation mobile phones
One day in April 1973, a man standing on streets of New York, took out a mobile phone about two large bricks, and hit a pass, attracted passers-by have stopped eyebrows. This man is the inventor of Madingkupa phone. At that time, Cooper is well-known U.S. Motorola’s engineering and technical personnel.
This is the world’s first mobile phone is the call through his work at Bell Labs, a rival, was also developed other mobile phones, but not yet succeeded. Cooper later recalled: “I called him, said: ‘Joe, I am now using a portable cellular phone talking to you.’ I heard the receiver other end of the ‘teeth’ – although he has maintained a considerable courtesy. ”
In April this year, mobile phones have been the 30th anniversary of the birth of a whole. This year the competition among technology products are now nearly ubiquitous to our modern life has brought great convenience.
Madingkupa this year has been 74 years, he worked at Motorola after 29 years in Silicon Valley set up his own communications technology research firm. Currently, he is the company’s chairman and chief executive. Madingkupa at that time, is to let the media know that wireless communications – especially a small mobile phone – is very valuable. In addition, he also hopes to stir interest in the U.S. Federal Communications Commission, the Motorola with AT & T (AT & T is a communications major U.S. company) competition, to support the former.
In fact, a step further back, we will find, mobile phone concept, early 40’s on there. At that time, the largest U.S. telecommunications company began trial production of Bell Labs. In 1946, Bell Labs and fashioned the first so-called mobile phone. However, too large, the researchers can only put it on the laboratory shelf, and slowly people will have forgotten.
Until the late 60’s, AT & T and Motorola, both companies began to be interested in this technology together. At that time, AT & T leased a kind of large volume of mobile phones, customers can bring this phone safety in trucks. AT & T’s plan is that in the future to develop a mobile phone, power is 10 watts, on the use of radio equipment on the truck to be communication. Cooper believes that this phone too heavy and can not move the people on the go. As a result, Motorola submitted to the U.S. Federal Communications Commission application for the mobile communication device provides the power, only to be tile, not more than 3 watts maximum. In fact, most cell phone radio power, the maximum is only 500 mW.
Phone registered patent from 1973 until 1985, before the birth of the first modern sense, the phone can really move. It is the power and the antenna placed in a box, weighing about 3 kg, very heavy and inconvenient for the user to walk like a backpack so carrying it, it was called “shoulder phone.”
Close to the present shape of mobile phones, was born in 1987. And “shoulder phone” in comparison, it seems much more compact, and easy to carry. Nevertheless, there are still about 750 g weight, and weighs only 60 grams today, compared to the phone, like a big brick.
Since then, more and more rapid development of mobile phones. In 1991, the phone weighs 250 grams; the fall of 1996, there has been volume of 100 cubic centimeters, weight of 100 grams of the phone. Followed by further small and light, to light in 1999 to 60 grams on the following. In other words, a cell phone is not much more than an egg weight was.
In addition to quality and smaller and smaller, the modern mobile phones have more and more like a multi-purpose Swiss Army knife was. In addition to basic phone functions, the new phone also can be used to send and receive mail and text messages, access to the Internet, play games, take pictures, or even a movie! This is the original inventor of mobile phones beyond the expectation.
In communications technology, modern cell phone also has improved significantly. When Cooper playing the world’s first GSM mobile phone, he can use any of the electromagnetic spectrum. In fact, by first-generation analog mobile phone is different to distinguish between different frequencies of the different mobile phone users. The second generation of mobile phones – GSM system is a very small time difference depends to distinguish users. Today, the frequency resources are clearly insufficient, mobile users exponentially growing rapidly. Thus, the updated, by coding to distinguish the different machines of different CDMA technology came into being. Application of this technique phone call quality and confidentiality is not only better but also reduce the radiation can be described as a “green phone.”