Technology: Microwaves

The microwave technology initially used by MCI was neither new nor unique; microwave communications were developed during World War II. AT&T and a number of other companies had used this technology in their communication businesses.

Microwave Antennas, Water Street New York
Microwave antenna, Water Street, New York

Microwaves offered a way for MCI to compete with AT&T’s control of all the telephone lines in the United States. Although it was impractical for MCI to run its own telephone lines, microwave towers could be installed nearly anywhere as long as there was a direct transmission line to the next tower. Telephone calls and data could then be transmitted via microwaves and connected back into the telephone system at their destination.

Thomas Leming (1924-2009), Senior Vice President of Transmission Systems, was responsible for the construction of the microwave network at MCI. William McGowan met him in 1971 as Leming was leaving his job with Continental Telephone. Leming taught at the Navy Radar school during World War II, helped develop microwave equipment for Motorola and Collins radio, and had experience in designing a microwave communications system similar to the one that MCI was about to build.

MCI System map of the U.S.
MCI system map

Leming’s challenge was immense: he needed to build a nationwide microwave network using a technology that had never before been used on that scale. In 1974, he succeeded, and MCI’s network reached coast-to-coast. It was not always reliable, and transmission quality often suffered, but it was complete, and it worked.