April 25, 2008
A cellular phone is a product of the combination of two great technologies: telephone and wireless communication. It should be noted that a cell phone is actually a radio or at least an extremely sophisticated radio. Before cell phones came to be, mobile communication abilities were usually provided by radio telephones installed in cars. There was one central antenna tower per city with about 25 channels available on such tower for the radio telephone system. However, there were not so many people that could use radio telephones due to the limited channels and the need for a very powerful transmitter just to transmit 40 or 50 miles away.
The genius of the cellular system lies in the division of a city into small cells which allowed for extensive frequency reuse across the area. This facilitated the simultaneous use of millions of people of their cell phones. Its amazing how inventions of the 1800s can still continue to produce better options as time goes by.