Monday, January 6, 2020

The History of Cellular Phones

In 1947, researchers looked at crude mobile (car) phones and realized that by using small cells (a range of service area) and found that with frequency reuse they could increase the traffic capacity of mobile phones substantially. However, the technology to do so at the time was nonexistent. Regulation Then there’s the issue of regulation. A cell phone is a type of two-way radio and anything to do with broadcasting and sending a radio or television message out over the airwaves is under the authority of Federal Communications Commission  (FCC) regulation. In 1947, ATT proposed that the FCC allocate a large number of radio-spectrum frequencies so that widespread mobile telephone service would become feasible, which would also give ATT an incentive to research the new technology. The agency’s response? The FCC decided to limit the number of frequencies available in 1947. The limits made only twenty-three phone conversations possible simultaneously in the same service area and gone was the market incentive for research. In a way, we can partially blame the FCC for the gap between the initial concept of cellular service and its availability to the public. It wasn’t until 1968 that the FCC reconsidered its position, stating that if the technology to build a better mobile service works, we will increase the frequencies allocation, freeing the airwaves for more mobile phones. With that, ATT and Bell Labs proposed a cellular system to the FCC of many small, low-powered, broadcast towers, each covering a â€Å"cell† a few miles in radius and collectively covering a larger area. Each tower would use only a few of the total frequencies allocated to the system. And as the phones traveled across the area, calls would be passed from tower to tower. Dr. Martin Cooper, a former general manager for the systems division at Motorola, is considered the inventor of the first modern portable handset. In fact,  Cooper made the first call on a portable cell phone in April 1973 to his rival, Joel Engel, who served as Bell Labs head of research. The phone was a prototype called the DynaTAC and weighed 28 ounces. Bell Laboratories had introduced the idea of cellular communications in 1947 with the police car technology, but it was Motorola that first incorporated the technology into a portable device designed for use outside of automobiles. By 1977, ATT and Bell Labs had constructed a prototype cellular system. A year later, public trials of the new system were held in Chicago with over 2,000 customers. In 1979, in a separate venture, the first commercial cellular telephone system began operation in Tokyo. In 1981, Motorola and American Radio telephone started a second U.S. cellular radiotelephone system test in the Washington/Baltimore area. And by 1982, the slow-moving FCC finally authorized commercial cellular service for the USA. So despite the incredible demand, it took cellular phone service many years to become commercially available in the United States. Consumer demand would soon outstrip the 1982 system standards and by 1987, cellular telephone subscribers exceeded one million with the airways becoming more and more crowded. There are basically three ways of improving services. Regulators can increase frequencies allocation, existing cells can be split and the technology can be improved. The FCC did not want to hand out any more bandwidth and building or splitting cells would have been expensive as well as add bulk to the network. So to stimulate the growth of new technology, the FCC declared in 1987 that cellular licensees could employ alternative cellular technologies in the 800 MHz band. With that, the cellular industry began to research new transmission technology as an alternative.

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