How did cellular communication come about?
At the start - a new type of communication
In fact, the ancestors of cellular mobile communications were radio telephone extenders and various autonomous radio networks. By the way, the Altai special communication radial-zone network, which was well-known in Soviet times, was used by the then state elite, provided mobility within hundreds of impressive size. Since there were few subscribers to this network, there was no question of saving the radio frequency resource at that time. Similar communications systems existed in other countries, but this was only a prelude to the future cellular communications. The introduction of real cellular networks began only after solutions were found to save the spectrum of radio frequencies and ways to determine the current location of mobile subscribers (for optimal routing of calls to them and ensuring communication continuity when the subscriber moves from one cell to another). Recall that the cellular topology made it possible to multiply the capacity of mobile networks in comparison with the existing networks of the radial structure, which does not include hand-off procedures (switching control when a subscriber moves from one cell to another).
The birth of cellular communication is attributed to 1971. It was then that the Bell System Company submitted to the US Federal Communications Commission (FCC) a description of the architecture of a radiotelephone communication, which later became known as cellular. But the path from the idea to the real project took quite a long time - commercial cellular networks started working only after 10 years.
The development of cellular systems in the 70s and their subsequent introduction in the 80s required the solution of various very complex technical problems. One of the most serious was the creation of wearable subscriber terminals of small size and weight. At the turn of the 70s, even advanced technological solutions for car terminals weighed a little less than 15 kg. And the same purpose device had to be implemented in size and weight, acceptable to hold with one hand near the ear. The first success was to flash off the Motorola specialists (USA).
Among the world famous pioneers of new areas of telecommunications is rightly Martin Cooper, who was in the early 70s as vice president of Motorola. He first suggested ways to drastically reduce the size of the radiotelephone. And in 1973, the first relatively small radio telephone was “born” and successfully passed laboratory tests. Martin Cooper made his first call to a competitor from Bell Laboratories. As Cooper himself testifies (an interview with him was published in PCweek newspaper No. 25 for 200), he said the following words: “Imagine, Joel, that I’m calling you from the world's first cell phone. He is in my hands, and I am walking along New York Street. ” As you know, long before this event, the birth of a conventional wired telephone was marked in a similar way: Alexander Graham Bell transmitted by wire: “Mr. Watson, go in! I need you". In the mid-1980s, the name Martin Cooper was placed in the Wireless Hall of Fame.
Today, Martin Cooper, despite his old age, is cheerful, he is obsessed with the idea of ​​creating effective wireless broadband Internet access. “The main question is whether the Internet will be wireless or cable, because people do not want to communicate with machines, but want to communicate with other people and use those devices that they can carry with them,” he said in an interview with a recent international conference "Internet World 2000". It seems that Internet access will soon undergo revolutionary changes, similar in consequence to the advent of cell phones. But this has already touched the new century.
The first cellular networks and the first problems.
The first cellular communication systems were analog and had one major drawback - the incompatibility of systems from different manufacturers. This significantly limited the ability to move subscribers between countries and even cities in which different types of systems were deployed. It is clear that the concept of roaming in those days was not always "well known" because of the unsolvable technological problems of network compatibility. Accordingly, sales of network and subscriber equipment were limited. And one more consumer deficiency already mentioned - the appearance and volume of subscriber terminals - for quite a long time forced developers to “scratch their heads” and constantly work on improving cell phones. Today, in the same case, the necessary elements are often placed to establish connections according to different standards, and such devices are called multimode cellular phones.
We will interrupt here our narration about the terminals and note the main strategic directions in which the cellular communication systems developed. The development went not only in the direction of increasing subscriber capacity or the transition from analog communication to digital, but also the number of additional services was constantly increasing - from voice mail to sending short messages or accessing the Internet. And what is important to note is that there was an increasing standardization and internationalization of radio interfaces (which is very important for the organization of roaming), as well as the unification of the interaction of a cellular communication network with a public telephone network.
Thus, the developers of cellular communication equipment have taken the path of reducing the number of existing standards. However, this was not always achieved in practice, and as a result, several zones with more or less stable “cellular orientation” appeared: North America, Western Europe and Japan. In other regions, a wider range of networks of various cellular standards can be found. Note that Japan is a fairly closed region in terms of using both cellular communication standards and radio frequency bands, and with this it protects the domestic market from strong foreign competitors and provides work to domestic companies.
Nevertheless, the dream of creating a universal global cellular network on a global scale has always attracted developers, who are now busy testing the cellular communication systems of the third generation. Having run a few steps ahead, we note that, despite all efforts, they have so far failed to reach a global consensus.
A number of incompatible cellular systems were used in various countries around the turn of the 1970s and 1980s: AMPS / NAMPS (USA, Canada, Australia), HCMTS (Japan), NMT (Scandinavian countries, Belgium, Netherlands, Luxembourg, Spain, Austria, Saudi Arabia), C-450 (Germany), TACS (United Kingdom and Ireland), ETAS (England, London), RTMS-101H (Italy), Radiocom-2000 (France). Most of these systems used radio frequencies of 450 and 800 MHz and, due to their uniqueness, were used rather locally. This way of development of cellular communication was a dead end for creating a global telecommunications space. Therefore, the process of gradual elimination of many standards from the market in the 80s became quite natural.
It is interesting that, despite the primacy of Americans in the ideology of building cellular networks, the first such network was not developed by any means. On September 1, 1981, a Scandinavian standard network NMT-450 (Nordic Mobile Telephone) was launched into commercial operation in Saudi Arabia, and exactly a month later, a similar network was launched in Stockholm. And only in October 1983, the network of the North American standard AMPS (Advanced Mobile Phone System) earned in Chicago.
Thus, analog cellular networks, so familiar to the modern user, began to be created in the early 80s in many European countries based on unified standard equipment (NMT-450) and in the USA based on AMPS standard. It was at that time that they were destined to take over the bulk of mobile subscribers all over the world.
NMT standard was interesting because for the first time its developers (from Scandinavian countries) were a team that pursued international telecommunication goals and was initially concerned about the idea of ​​providing international roaming. Therefore, NMT networks have become revolutionary for their time. And only in the 90s they began to lose subscribers due to the massive development of digital networks, having a number of significant advantages.
In fact, the ancestors of cellular mobile communications were radio telephone extenders and various autonomous radio networks. By the way, the Altai special communication radial-zone network, which was well-known in Soviet times, was used by the then state elite, provided mobility within hundreds of impressive size. Since there were few subscribers to this network, there was no question of saving the radio frequency resource at that time. Similar communications systems existed in other countries, but this was only a prelude to the future cellular communications. The introduction of real cellular networks began only after solutions were found to save the spectrum of radio frequencies and ways to determine the current location of mobile subscribers (for optimal routing of calls to them and ensuring communication continuity when the subscriber moves from one cell to another). Recall that the cellular topology made it possible to multiply the capacity of mobile networks in comparison with the existing networks of the radial structure, which does not include hand-off procedures (switching control when a subscriber moves from one cell to another).
The birth of cellular communication is attributed to 1971. It was then that the Bell System Company submitted to the US Federal Communications Commission (FCC) a description of the architecture of a radiotelephone communication, which later became known as cellular. But the path from the idea to the real project took quite a long time - commercial cellular networks started working only after 10 years.
The development of cellular systems in the 70s and their subsequent introduction in the 80s required the solution of various very complex technical problems. One of the most serious was the creation of wearable subscriber terminals of small size and weight. At the turn of the 70s, even advanced technological solutions for car terminals weighed a little less than 15 kg. And the same purpose device had to be implemented in size and weight, acceptable to hold with one hand near the ear. The first success was to flash off the Motorola specialists (USA).
Among the world famous pioneers of new areas of telecommunications is rightly Martin Cooper, who was in the early 70s as vice president of Motorola. He first suggested ways to drastically reduce the size of the radiotelephone. And in 1973, the first relatively small radio telephone was “born” and successfully passed laboratory tests. Martin Cooper made his first call to a competitor from Bell Laboratories. As Cooper himself testifies (an interview with him was published in PCweek newspaper No. 25 for 200), he said the following words: “Imagine, Joel, that I’m calling you from the world's first cell phone. He is in my hands, and I am walking along New York Street. ” As you know, long before this event, the birth of a conventional wired telephone was marked in a similar way: Alexander Graham Bell transmitted by wire: “Mr. Watson, go in! I need you". In the mid-1980s, the name Martin Cooper was placed in the Wireless Hall of Fame.
Today, Martin Cooper, despite his old age, is cheerful, he is obsessed with the idea of ​​creating effective wireless broadband Internet access. “The main question is whether the Internet will be wireless or cable, because people do not want to communicate with machines, but want to communicate with other people and use those devices that they can carry with them,” he said in an interview with a recent international conference "Internet World 2000". It seems that Internet access will soon undergo revolutionary changes, similar in consequence to the advent of cell phones. But this has already touched the new century.
The first cellular networks and the first problems.
The first cellular communication systems were analog and had one major drawback - the incompatibility of systems from different manufacturers. This significantly limited the ability to move subscribers between countries and even cities in which different types of systems were deployed. It is clear that the concept of roaming in those days was not always "well known" because of the unsolvable technological problems of network compatibility. Accordingly, sales of network and subscriber equipment were limited. And one more consumer deficiency already mentioned - the appearance and volume of subscriber terminals - for quite a long time forced developers to “scratch their heads” and constantly work on improving cell phones. Today, in the same case, the necessary elements are often placed to establish connections according to different standards, and such devices are called multimode cellular phones.
We will interrupt here our narration about the terminals and note the main strategic directions in which the cellular communication systems developed. The development went not only in the direction of increasing subscriber capacity or the transition from analog communication to digital, but also the number of additional services was constantly increasing - from voice mail to sending short messages or accessing the Internet. And what is important to note is that there was an increasing standardization and internationalization of radio interfaces (which is very important for the organization of roaming), as well as the unification of the interaction of a cellular communication network with a public telephone network.
Thus, the developers of cellular communication equipment have taken the path of reducing the number of existing standards. However, this was not always achieved in practice, and as a result, several zones with more or less stable “cellular orientation” appeared: North America, Western Europe and Japan. In other regions, a wider range of networks of various cellular standards can be found. Note that Japan is a fairly closed region in terms of using both cellular communication standards and radio frequency bands, and with this it protects the domestic market from strong foreign competitors and provides work to domestic companies.
Nevertheless, the dream of creating a universal global cellular network on a global scale has always attracted developers, who are now busy testing the cellular communication systems of the third generation. Having run a few steps ahead, we note that, despite all efforts, they have so far failed to reach a global consensus.
A number of incompatible cellular systems were used in various countries around the turn of the 1970s and 1980s: AMPS / NAMPS (USA, Canada, Australia), HCMTS (Japan), NMT (Scandinavian countries, Belgium, Netherlands, Luxembourg, Spain, Austria, Saudi Arabia), C-450 (Germany), TACS (United Kingdom and Ireland), ETAS (England, London), RTMS-101H (Italy), Radiocom-2000 (France). Most of these systems used radio frequencies of 450 and 800 MHz and, due to their uniqueness, were used rather locally. This way of development of cellular communication was a dead end for creating a global telecommunications space. Therefore, the process of gradual elimination of many standards from the market in the 80s became quite natural.
It is interesting that, despite the primacy of Americans in the ideology of building cellular networks, the first such network was not developed by any means. On September 1, 1981, a Scandinavian standard network NMT-450 (Nordic Mobile Telephone) was launched into commercial operation in Saudi Arabia, and exactly a month later, a similar network was launched in Stockholm. And only in October 1983, the network of the North American standard AMPS (Advanced Mobile Phone System) earned in Chicago.
Thus, analog cellular networks, so familiar to the modern user, began to be created in the early 80s in many European countries based on unified standard equipment (NMT-450) and in the USA based on AMPS standard. It was at that time that they were destined to take over the bulk of mobile subscribers all over the world.
NMT standard was interesting because for the first time its developers (from Scandinavian countries) were a team that pursued international telecommunication goals and was initially concerned about the idea of ​​providing international roaming. Therefore, NMT networks have become revolutionary for their time. And only in the 90s they began to lose subscribers due to the massive development of digital networks, having a number of significant advantages.
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Source: https://habr.com/ru/post/96542/
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