The history of mobile phone development:
If we trace back, we will find that the concept of mobile phones appeared as early as the 1940s. At that time, Bell Labs, the largest communications company in the United States, began trial production. In 1940, Bell Labs created the first so-called mobile communication phone. However, due to the size, the researchers can only put it on the shelf of the laboratory, and people will soon forget it.
In April 1973, the famous American Motorola engineering engineer "Martin Cooper" invented the world's first mobile phone for civilian use. When Cooper hits the world's first mobile phone, he can use any electromagnetic frequency band. In fact, the first generation of analog mobile phones relied on different frequencies to distinguish different mobile phones of different users. The second generation of mobile phones, the GSM system, relies on extremely small time differences to differentiate users. Today, frequency resources are obviously insufficient, and mobile phone users are also experiencing rapid growth in geometric progression. Therefore, the updated CDMA technology that distinguishes different machines by different coding has emerged. Mobile phones that use this technology not only have better call quality and confidentiality, but also reduce radiation, which can be called a "green phone."
In 1831, the British Faraday discovered the phenomenon of electromagnetic induction. Maxwell further elaborated the research results of Faraday and others using mathematical formulas, and extended the theory of electromagnetic induction to space. After more than 60 years, Hertz confirmed the existence of electromagnetic waves in experiments. The discovery of electromagnetic waves has become a turning point in "wireless communication" to "radio communication" and has become the source of the entire mobile communication. As one scientist said, "The mobile phone is born on the shoulders of telegraphs and telephones. Without the efforts of the predecessors, wireless communication cannot be discussed.
May 24, 1844. Morse's telegraph machine sent the first telegram of human history from Washington to Baltimore "What miracle God has created!"
On June 2, 1875, when Bell was doing the experiment, he accidentally splashed sulfuric acid on his lap. He hurts to call a colleague in another room, "Live, come help me!" and this sentence was transmitted to the living ear in another room by the phone in the experiment, and it was transmitted by humans by telephone. the first word.
In 1902, an American named "Nathan Stubbfield" made the first wireless telephone device in a rural home in Murray, Kentucky. This wireless mobile communication phone is human "mobile phone." "The earliest exploration of technology.
In 1940, Bell Labs of the United States produced a mobile phone in the field.
In 1946, the world made the first call from a traveling car in St. Louis to make a call with a mobile phone.
In 1957, the outstanding engineer of the Soviet Union, Leonid. Kupriyanovic invented the ЛК-1 mobile phone. In 1958, he had made further improvements to his mobile phone. The weight of the device has been reduced from 3 kg to 500 g (including battery weight), and the shape has been reduced to two cigarette packs. It can be dialed anywhere in the city and can be connected to any fixed telephone. By the middle of the 60th year, Kupriyanovic's mobile phone had been able to work effectively within 200 kilometers.
In 1958, the Soviet Union began to develop the world's first fully automatic mobile phone communication system "Altai" (Алтай). In 1959, the outstanding Altai system won a gold medal at the Brussels Expo.
In 1973, a man stood on the streets of New York and pulled out a wireless telephone with about two bricks and started talking.
This person is the inventor of the mobile phone Martin Cooper. At the time, he was also an engineering technician at Motorola. This was the first mobile phone in the world at the time.
In 1975, the Federal Communications Commission (FCC) of the United States determined the spectrum of land mobile phone communications and high-capacity cellular mobile phones. Prepare for the commercialization of mobile phones.
In 1979, Japan opened the world's first cellular mobile telephone network.
In 1982, Europe established the GSM (Mobile Communications Special Group).
In 1985, the first modern mobile phone that could be commercialized was born. It puts the power supply and antenna in an example and weighs 3 kg.
The mobile phone, which is close to the modern shape, was born in 1987. It weighs about 750 grams and is like a big brick compared to today's phone, which weighs only 60 grams.
Since then, the "slimming" of mobile phones has become more and more rapid. In 1991, the weight of the mobile phone was about 250 grams. In the autumn of 1996, a cell phone with a volume of 100 cubic centimeters and a weight of 100 grams appeared. Since then, it has been further miniaturized and lightened, and by 1999 it was as light as 60 grams.
手机的发展史：
如果追溯我们会发现，手机这个概念早在40年代就出现了。当时是美国最大的通讯公司贝尔实验室开始试制的。1940年，贝尔实验室造出了第一部所谓的移动通讯电话。但是，由于体积太大，研究人员只能把它放在实验室的架子上，慢慢人们就淡忘了。
1973年4月，美国著名的摩托罗拉公司工程技术员“马丁·库帕”发明世界上第一部推向民用的手机。当库帕打世界第一通移动电话时，他可以使用任意的电磁频段。事实上，第一代模拟手机就是靠频率的不同来区别不同用户的不同手机。第二代手机——GSM系统则是靠极其微小的时差来区分用户。到了今天，频率资源已明显不足，手机用户也呈几何级数迅速增长。于是，更新的、靠编码的不同来区别不同的机的CDMA技术应运而生。应用这种技术的手机不但通话质量和保密性更好，还能减少辐射，可称得上是“绿色手机”。
1831年，英国的法拉第发现了电磁感应现象，麦克斯韦进一步用数学公式阐述了法拉第等人的研究成果，并把电磁感应理论推广到了空间。而60多年后赫兹在实验中证实了电磁波的存在。电磁波的发现，成为"有线电通信"向"无线电通信"的转折点，也成为整个移动通信的发源点。正如一位科学家说的那样"手机是踩着电报和电话等的肩膀降生的，没有前人的努力，无线通信无从谈起。
1844年5月24日。莫尔斯的电报机从华盛顿向巴尔的摩发出人类历史的第一份电报"上帝创造了何等奇迹!"
1875年6月2日，贝尔做实验的时候，不小心把硫酸溅到了自己的腿上。他疼得对另一个房间的同事喊到"活，快来帮我啊!"而这句话通过实验中的电话传到了在另一个房间接听电话的活特耳里，成为人类通过电话传送的第一句话。
1902年，一位叫做“内森·斯塔布菲尔德”的美国人在肯塔基州默里的乡下住宅内制成了第一个无线电话装置，这部可无线移动通讯的电话就是人类对“手机”技术最早的探索研究 。
1940年，美国贝尔实验室制造出战地移动电话机。
1946年，世界上从圣路易斯的一辆行进的汽车中打出了第一个电话用移动电话所拨打电话。
1957年，苏联杰出的工程师列昂尼德。库普里扬诺维奇发明了ЛК-1型移动电话。1958年，他已对自己的移动电话做了进一步改进。设备重 量从3公斤减轻至500克(含电池重量)，外形精简至两个香烟盒大小，可向城市里的任何地方进行拨打，可接通任意一个固定电话。到60年中期，库普里扬诺 维奇的移动电话已能够在200公里范围内有效工作 。
1958年，苏联开始研制世界上第一套全自动移动电话通讯系统“阿尔泰”(Алтай) 。1959年，性能杰出的“阿尔泰”系统在布鲁塞尔世博会上获得金奖 。
1973年，一名男子站在纽约的街头，掏出一个约有两块砖头大的无线电话，并开始通话。
这个人就是手机的发明者马丁·库帕。当时他还是摩托罗拉公司的工程技术人员。这是当时世界上第一部移动电话。
1975年，美国联邦通信委员会(FCC)确定了陆地移动电话通信和大容量蜂窝移动电话的频谱。为移动电话投入商用做好了准备 。
1979年，日本开放了世界上第一个蜂窝移动电话网。
1982年，欧洲成立了GSM(移动通信特别组)。
1985年，第一台现代意义上的可以商用的移动电话诞生。它是将电源和天线放置在一个例子里，重量达3公斤。
与现代形状接近的手机，则诞生于1987年。其重量仍有大约750克，与今天仅重60克的手机相比，象一块大砖头。
此后，手机的"瘦身"越来越迅速。1991年，手机重量为250克左右。1996年秋出现了体积为100立方厘米，重量为100克的手机。此后又进一步小型化，轻型化，到1999年就轻到了60克以下。
Comentários