Handheld Wireless Telephone

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On 3 April 1973, Motorola vice president Martin Cooper displayed the DynaTac (Dynamic Adaptive Total Area Coverage), a 28-ounce portable telephone, on the streets of New York City. He predicted that wireless phones “could be reduced" to "fit in a breast pocket." The initial model, the DynaTac 8000X, cost $3995 and weighed nearly two pounds.

Although wireless telephones had been developed as early as the 1947 at Bell Labs, two major hurdles stood in the way of the wide adoption of this technology. The first was the availability of radio frequency spectrum. Single-tower antennas could only serve a small geographic range and just a few thousand customers. A cellular system of multiple small base stations had to be developed to share a radio frequency across a much longer distance. The second problem was the size of the receiver. A single-tower system demanded significant power from a receiver to reach the station. But a system of widely-dispersed base stations meant that a caller needed much less power to reach a station. As a result, phones could be shrunk to a handheld size.

Motorola was a pioneer in the business of portable radio communications. In the 1930, it introduced the first commercially-viable car radio, and built communications technologies for the defense industry during World War II such as the first walkie-talkie. In the 1950s, its projects included the development of amateur “ham” radios, televisions, phonographs, and solid-state germanium transistors.

In 1960, John F. Mitchell became chief engineer of Motorola’s mobile and portable products division. He oversaw the development of a mobile phone that would be light enough to carry by hand and could run on a battery, rather than a running automobile engine. In the late 1960s, Mitchell’s team also worked on building a cellular network know as AMPS (Advanced Mobile Phone System), an analog mobile phone standard. Motorola would build this network around radio frequency spectrum released by the Federal Communications Commission to encourage the development of two-way radio applications.

Motorola’s prototype for the world’s first cellular phone, the DynaTac, was successfully tested in 1973. Hefty by modern standards, this phone sent signals to a radio receiver, which forwarded them to a central computer and then fed them to a regular analog telephone network. The computer improved the quality of the calls by switching the conversation to different transmitters as the caller moved through the DynaTac cellular network, which, at the time, meant sections of the New York metropolitan area. This coordination was possible thanks to the contemporary invention of integrated circuits that could squeeze thousands of transistors onto a tiny silicon chip. Integrated circuits allowed each phone to contain a miniature computer that demanded very little power and could perform the functions of a two-way radio. Over a ten year period, Motorola built eight different prototypes of the 8000X, spending perhaps $100 million on the phone.

Despite Motorola’s early lead in cellular technology, analysts within and without the company doubted that cellphones would have appeal beyond a niche market—a rich man’s toy. The phone’s cost, size, weight, and limited battery life—you could only talk for a half hour before it gave out—made it seem more of a status symbol in 1984 rather than a practical tool. A 1978 study by the consultancy McKinsey & Co. concluded that, by 2000, just 900,000 users would own cellular subscriptions. In fact, the industry was making 900,000 phones every day by 2000, and the market would quickly expand into billions of users worldwide.