Martin Cooper

Martin Cooper led the team at Motorola that built the first handheld mobile telephone and made the first call on one, in 1973. Born in Chicago in 1928 to Ukrainian Jewish immigrants, he took degrees in electrical engineering at the Illinois Institute of Technology, served as a submarine officer in the Korean War, and joined Motorola in 1954. He worked on portable radio equipment, including the first handheld police radios for the Chicago force in 1967, which taught him what people would actually carry and use. The competitive situation shaped the invention. AT&T's Bell Labs was developing cellular telephony as a car-based service, with the handset wired into the vehicle, and was lobbying the Federal Communications Commission for spectrum on that basis. Cooper's argument was that a telephone should be attached to a person, not to a place or a car, and that people are inherently mobile. His team built a working handset in about ninety days. The DynaTAC weighed roughly a kilogram, was about twenty-five centimetres long, took ten hours to charge and gave twenty-five minutes of talk time. On 3 April 1973, standing on Sixth Avenue in Manhattan, he called Joel Engel, his opposite number at Bell Labs, and told him he was calling from a personal, handheld, portable cell phone. He has said Engel went quiet. The demonstration helped persuade the FCC to allocate spectrum for handheld cellular, and the first commercial DynaTAC went on sale in 1983 for about 3,900 dollars. He later founded companies working on spectrum efficiency and wireless metering, formulated Cooper's law on spectrum capacity, and has said he limits his own screen time.

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