How cell phones work- history of cellular technology and wireless cell phones.
Dr. Martin Cooper


By Mary Bellis
Cellular: A type of wireless communication that is most familiar to mobile phones users. It's called 'cellular' because the system uses many base stations to divide a service area into multiple 'cells'. Cellular calls are transferred from base station to base station as a user travels from cell to cell. - definition from the Wireless Advisor Glossary.

The basic concept of cellular phones began in 1947, when researchers looked at crude mobile (car) phones and realized that by using small cells (range of service area) with frequency reuse they could increase the traffic capacity of mobile phones substantially. However at that time, the technology to do so was nonexistent.

Anything to do with broadcasting and sending a radio or television message out over the airwaves comes under Federal Communications Commission (FCC) regulation. A cell phone is a type of two-way radio. In 1947, AT&T proposed that the FCC allocate a large number of radio-spectrum frequencies so that widespread mobile telephone service would become feasible and AT&T would have a incentive to research the new technology. We can partially blame the FCC for the gap between the initial concept of cellular service and its availability to the public. The FCC decided to limit the amount of frequencies available in 1947, the limits made only twenty-three phone conversations possible simultaneously in the same service area - not a market incentive for research.

The FCC reconsidered its position in 1968, stating "if the technology to build a better mobile service works, we will increase the frequencies allocation, freeing the airwaves for more mobile phones." AT&T and Bell Labs proposed a cellular system to the FCC of many small, low-powered, broadcast towers, each covering a '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. As the phones traveled across the area, calls would be passed from tower to tower.

Individual Inventors & Mobile Phone Patents

Dr. Martin Cooper for Motorola.
US03906166
09/16/1975
Radio telephone system
Inventors: Martin Cooper, Richard W. Dronsuth, ; Albert J. Mikulski, Charles N. Lynk Jr., James J. Mikulski, John F. Mitchell, Roy A. Richardson, John H. Sangster

Dr Martin Cooper, a former general manager for the systems division at Motorola, is considered the inventor of the first modern portable handset. Cooper made the first call on a portable cell phone in April 1973. He made the call to his rival, Joel Engel, Bell Labs head of research. Bell Laboratories introduced the idea of cellular communications in 1947 with the police car technology. However, Motorola was the first to incorporate the technology into portable device that was designed for outside of a automobile use. Cooper and his co-inventors are listed above.

By 1977, AT&T and Bell Labs had constructed a prototype cellular system. A year later, public trials of the new system were started in Chicago with over 2000 trial 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 radio-telephone system test in the Washington/Baltimore area. By 1982, the slow-moving FCC finally authorized commercial cellular service for the USA. A year later, the first American commercial analog cellular service or AMPS (Advanced Mobile Phone Service) was made available in Chicago by Ameritech.

Despite the incredible demand, it took cellular phone service 37 years to become commercially available in the United States. Consumer demand quickly outstripped the 1982 system standards. By 1987, cellular telephone subscribers exceeded one million and the airways were crowded.

Three ways of improving services existed:

one - increase frequencies allocation
two - split existing cells
three - improve the technology
The FCC did not want to handout any more bandwidth, and building/splitting cells would have been expensive and would have added bulk to the network. 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. The cellular industry began to research new transmission technology as an alternative.
Editor's Note: African American Inventor Henry Sampson did not invent the cell phone. Sampson is a brilliant and accomplished inventor who invented a Gamma-Electrical Cell and not a phone cell. Sampson's patent (US 3,591,860) can be viewed online or in person at the United States Patent and Trademark Office.