Cell Phone Story You Didn't Know

The mobile phone or cell phone is an indispensable device today; However, its popularization has been a very recent phenomenon. At first, th...

Thursday, June 18, 2020

Cell Phone Story You Didn't Know

The mobile phone or cell phone is an indispensable device today; However, its popularization has been a very recent phenomenon. At first, the mobile phone could only be used in vehicles due to its size, subsequently reducing it to a portable unit, and finally to the pocket size that is used today.

The cellular system was created to meet the demand for mobile communication within a limited radio frequency spectrum. This limitation is the original factor that motivated and continues to motivate the development of the mobile phone, compared to other various factors such as battery life or device size.

Radio emerged as an alternative to cable communication in the late 19th century. At first it was used for maritime communication, but from the 1920s onwards attempts to apply it also to mobile communication on land began. In 1923, the Victoria, Australia, police force was the first to use duplex wireless communication in cars, ending the practice of police reporting in public phone booths, These early mobile phones remained restricted to government use until the 1940s, when it spread to the general public.

The first commercial mobile telephone service appeared in 1946 in Saint Louis, United States. The AT&T company then began operating the MTS, or Mobile Telephone System, which two years later would be available in more than 100 cities and Highways Due to limitations in the radio frequency spectrum, the system allowed a maximum of six channels, resulting in long waiting lists. In the 1960s, the Improved Mobile Telephone Service would offer a total of 44 channels per city. In 1964, the United States had 1.5 million mobile phone users.

In Europe, the first mobile telephone network was installed by the Swedish national telephone company, Televerket, in 1955.

The first kits were large and heavy, so they were almost exclusively intended for use on board vehicles. Generally the radio equipment was installed in the trunk and a cable was passed through the phone to the dashboard of the car. Although in the 1940s the equipment occupied the entire boot, in the 1960s its size had been reduced to that of a briefcase thanks to the invention of the transistor. The transistor, created in 1948 at Bell Laboratories, would replace vacuum tubes to amplify and switch signals, ushering in the era of miniaturization of electronic devices.

In the Soviet Union, L. I. Kupriyanovich developed between 1957 and 1961 a series of experimental pocket-sized communications radio models. One such model, introduced in 1961, weighed just 70 grams and fit in the palm of one hand.9 10 However, the Soviet Union made the decision to first develop the Altay mobile phone system for cars, which It was commercially distributed in 1963.

These systems were not yet cellular. Each phone functioned as a city-wide transmitter on a fixed frequency, or in other words, each phone was a city-wide radio station, transmitting signals with high power so that it could be received in the widest possible area. This was a problem due to the scarcity of useful radio frequency spectrum, which meant that only about 44 users could communicate simultaneously in a city The system did not cover the demand; the service was reserved for a privileged few.

The cellular system consists of subdivision of a territory into small areas (called cells), each with a transmission antenna, so that the same frequency can be used in different areas at the same time within a city. This allows a much more efficient use of the spectrum. The smaller the cells, the more frequencies can be reused and the more users can use the service.

The first description of a cellular system appeared in a work by D.H. Ring, from Bell Laboratories, in 1947.2 12 But it would not be implemented until two decades later for various reasons. First of all, cell phones must operate at high frequencies, where transmissions can be limited to small cells. But the technology necessary to be able to work with such high frequencies would not come until later. Furthermore, in order to implement the cellular system, a user crossing the city should be able to move from one cell to another without the call being cut off. This requires the system to be able to know where the user left the first cell, locate the next one, and automatically spin the conversation between cells. In other words, the system needs a database with information about where the phone was, where it was going, and who was using it; And this database had to be fast. In the 1940s it was not possible to do this quickly enough not to interrupt the call. On the other hand, in order to transmit and receive all the necessary information, the phone had to include a frequency synthesizer, a piece that when it began to be developed for the army in the 1960s cost as much as a good car.
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Thursday, January 2, 2020

What is technology for us?

Technology is the science applied to solving specific problems. It constitutes a set of scientifically ordered knowledge that allows the design and creation of goods or services that facilitate adaptation to the environment, as well as the satisfaction of the essential individual needs and aspirations of humanity. 'technology' is a word of Greek origin, τεχνολογία, formed by téchnē (τέχνη, art, technique or trade, which can be translated as skill) and logics (λογία, the study of something).

Although there are many very different technologies from each other, it is common to use the term technology in the singular to refer to all of them, or also to one of them in particular. The word technology can also refer to the theoretical discipline that studies the common knowledge of all technologies, and in some contexts, to technological education, the school discipline focused on familiarization with the most important technologies.

Technological activity influences social and economic progress, but if its application is merely commercial, it can be oriented to satisfy the wishes of the most prosperous (consumerism) and not to meet the essential needs of the most needy. This approach can encourage unsustainable use of the environment. Certain human technologies, due to their intensive, direct or indirect use, of the biosphere, are the main cause of the increasing depletion and degradation of the planet's natural resources.

However, technology can also be used to protect the environment, seeking innovative and efficient solutions to sustainably meet the growing needs of society, without causing depletion or degradation of the planet's material and energy resources or increasing inequalities. social. Certain human technologies have led to a huge advance in the standards and quality of life of billions of people on the planet, simultaneously achieving better environmental conservation.

Technology encompasses any set of systematic actions whose destiny is the transformation of things, that is, their purpose is to know how to do and know why it is done.

There is currently a technological era, a historical stage dominated by the production of goods and by their commercialization, in which the energy factor plays a key role. All scientific and technical activity permanently gravitates on human well-being, on social progress and economic of the towns and on the environment where the industrial activity is manifested.
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